KR20220163324A - White organic light emitting device - Google Patents

Abstract

The present invention provides a white organic light emitting device capable of improving luminous efficiency and panel efficiency. The white organic light emitting device according to the present invention comprises: a first light emitting unit disposed between a first electrode and a second electrode and including a first light emitting layer; a second light emitting unit disposed on the first light emitting unit and including a second light emitting layer; and a third light emitting unit disposed on the second light emitting unit and including a third light emitting layer. According to an embodiment of the present invention, the first light emitting unit, the second light emitting unit, and the third light emitting unit have an emission position of emitting layers (EPEL) structure having a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer.

Description

White organic light emitting device {WHITE ORGANIC LIGHT EMITTING DEVICE}

The present invention relates to an organic light emitting device, and more particularly, to a white organic light emitting device capable of improving luminous efficiency.

Recently, as we enter the information age, the display field that visually expresses electrical information signals has developed rapidly. device) is being developed.

Specific examples of such a flat panel display device include a liquid crystal display device (LCD), a plasma display panel device (PDP), a field emission display device (FED), and an organic light emitting display device. (Organic Light Emitting Device: OLED) etc. are mentioned.

In particular, the organic light emitting display device is a self-light emitting device and has advantages of a fast response speed and a large luminous efficiency, luminance, and viewing angle compared to other flat panel display devices.

An organic light emitting display device forms an organic light emitting layer between two electrodes. Electrons and holes are respectively injected from the two electrodes into the organic light emitting layer to generate excitons according to the combination of electrons and holes. And, it is a device using the principle of generating light when the generated excitons fall from an excited state to a ground state.

A conventional organic light emitting display device includes a blue light emitting layer made of a blue luminescent material to implement white light. However, the theoretical quantum efficiency of a light emitting layer made of a fluorescent material is about 25% higher than that of a light emitting layer made of a phosphorescent material. Due to this, there is a problem in that the blue light emitting layer made of a fluorescent material does not provide sufficient luminance compared to a phosphorescent material.

[White organic light emitting device] (Patent Application No. 10-2009-0092596)

Conventional organic light-emitting devices have limitations in light-emitting characteristics and lifetime performance due to the material and light-emitting structure of the organic light-emitting layer, and thus, various methods for improving light-emitting efficiency and lifespan have been proposed.

As one method, there is a method of using a light emitting layer as a single layer. In this method, a white organic light emitting diode can be manufactured by using a single material or doping two or more materials. For example, there is a method of using red and green dopants in a blue host or adding red, green and blue dopants to a host material having a large band gap energy. However, this method has problems in that energy transfer to the dopant is incomplete and it is difficult to control the balance of white color.

In addition, there is a limit to the components of the dopant included in the light emitting layer due to the characteristics of the dopant itself. In addition, when mixing each light emitting layer, the focus is on realizing white light, so that it exhibits wavelength characteristics with an emitting peak value at a wavelength other than red, green, and blue. do. Therefore, there is a problem in that the color reproducibility is lowered when the color filter is included. In addition, the lifespan of the dopant material is different, and a color shift occurs during continuous use.

Alternatively, a structure that emits white light may be obtained by stacking two light emitting layers having a complementary color relationship. However, in this structure, when white light passes through the color filter, a difference occurs between the peak wavelength region of each light emitting layer and the transmission region of the color filter. Therefore, it may be difficult to implement a desired color gamut due to a narrow range of colors that can be expressed.

For example, when a blue light emitting layer and a yellow light emitting layer are stacked, white light is emitted while peak wavelengths are formed in a blue wavelength region and a yellow wavelength region. When the white light passes through the red, green, and blue color filters, respectively, the transmittance of the blue wavelength region is lowered compared to the red or green wavelength region, and thus the luminous efficiency and color reproducibility are lowered.

In addition, the luminous efficiency of the yellow phosphorescent light emitting layer is relatively higher than that of the blue fluorescent light emitting layer, and the efficiency difference between the phosphorescent light emitting layer and the fluorescent light emitting layer reduces panel efficiency and color gamut. In addition, there is a problem that the luminance of blue is relatively lower than that of yellow.

In addition to this structure, in the case of a structure in which a blue fluorescent light emitting layer and a green-red phosphorescent light emitting layer are stacked, there is a problem that the luminance of blue is relatively lower than that of green-red.

As mentioned above, several methods have been proposed to increase the luminous efficiency. However, there is a limit to adjusting the dopant component or the amount of the dopant included in the light emitting layers in order to improve the characteristics of the light emitting layers.

In addition, the thickness of the light emitting layers, the number of light emitting layers, and the thickness of the organic layers or the number of organic layers may be adjusted in order to improve the luminous efficiency of the light emitting layers at a desired emitting peak. However, when the light emitting layers or the organic layers are formed thickly, process increases and life span decrease, so it is difficult to apply them to a large-area organic light emitting display device.

Therefore, the inventors of the present invention recognized the above-mentioned problems, and carried out various experiments in which the light emitting layers could emit light in a desired light emitting area to improve the light emitting efficiency, regardless of the thickness or number of the light emitting layers and regardless of the thickness or number of the organic layers. I did.

As already described, in order to improve the luminous efficiency, two or more light emitting layers may be formed to realize a desired white color, but this increases the thickness of the device, resulting in an increase in the driving voltage of the device. And, although the organic layers constituting the light emitting unit may be composed of several layers having electron or hole movement characteristics, there is a problem in that the driving voltage of the device increases because the thickness of the device is increased. In addition, it was recognized that it is very difficult to set a desired number or thickness because the number or thickness of the organic layers affects the luminous efficiency or luminous intensity of the light emitting layer. Accordingly, it has been recognized that it is very difficult to construct a device capable of realizing a desired white color without increasing the thickness of the device, including organic layers having desired characteristics and a desired number or thickness.

Accordingly, the inventors of the present invention propose a structure in which a blue light emitting layer and a yellow-green light emitting layer are stacked in addition to a structure in which a light emitting layer is stacked in order to improve the efficiency of the blue light emitting layer through various experiments. In addition, a bottom emission type white organic light emitting diode having a new structure capable of improving the light emitting efficiency of the light emitting layer and the panel efficiency in this structure has been invented.

In addition, the inventors of the present invention, through various experiments, invented a top emission type white organic light emitting device having a new structure in which the luminous efficiency of the light emitting layer and the panel efficiency can be improved, and the luminance is improved because a polarizer is not used.

The problem to be solved according to an embodiment of the present invention is to achieve maximum efficiency in the light emitting area of the light emitting layer by applying an EPEL (Emission Position of Emission Layers) structure in which the light emitting position of the light emitting layer corresponding to the light emitting area of the light emitting layer is set, It is an object of the present invention to provide a white organic light emitting device of a bottom emission type capable of improving luminous efficiency and panel efficiency.

In addition, a problem to be solved according to an embodiment of the present invention is to apply an EPEL (Emission Position of Emission Layers) structure in which a light emitting position is set to a light emitting layer, thereby improving light emitting efficiency, panel efficiency, and luminance. It is to provide a light emitting element.

In addition, the problem to be solved according to an embodiment of the present invention is a white organic light emitting device having an Emission Position of Emission Layers (EPEL) structure regardless of the number of at least one organic layer, the thickness of the organic layer, the number of light emitting layers, and the thickness of the light emitting layer. is to provide

A white organic light emitting device according to the present invention includes a first light emitting portion positioned between a first electrode and a second electrode and including a first light emitting layer, and a second light emitting portion positioned on the first light emitting portion and including a second light emitting layer. A light emitting unit and a third light emitting unit disposed on the second light emitting unit and including a third light emitting layer are disposed. According to an embodiment of the present invention, the first light emitting unit, the second light emitting unit, and the third light emitting unit correspond to the light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer, A white organic light emitting device capable of improving light emitting efficiency and panel efficiency of the light emitting layer by having an EPEL (Emission Position of Emitting Layers) structure having a maximum light emitting range in the light emitting regions of the second light emitting layer and the third light emitting layer.

The organic light emitting device may be a bottom emission type organic light emitting device.

The position of the first electrode may be set within a range of 4,500 Å to 6,000 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 200 Å to 800 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,800 Å to 2,550 Å from the second electrode.

A light emitting position of the first light emitting layer may be set within a range of 2,650 Å to 3,300 Å from the second electrode.

The position of the second electrode may be set within a range of 4,500 Å to 6,000 Å from the first electrode.

A light emitting position of the first light emitting layer may be set within a range of 2,000 Å to 2,650 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,750 Å to 3,500 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 4,500 Å to 5,100 Å from the first electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the first electrode may be set within a range of 3,500 Å to 4,500 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 250 Å to 800 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,450 Å to 1,950 Å from the second electrode.

An emission position of the first emission layer may be set within a range of 2,050 Å to 2,600 Å from the second electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

The location of the second electrode may be set within a range of 3,500 Å to 4,500 Å from the first electrode.

A light emitting position of the first light emitting layer may be set within a range of 1,500 Å to 2,050 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,150 Å to 2,600 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 3,300 Å to 3,850 Å from the first electrode.

The organic light emitting device may be a top emission type organic light emitting device.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

A light emitting position of the first light emitting layer may be set in a range of 150 Å to 700 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,600 Å to 2,300 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,400 Å to 3,100 Å from the first electrode.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

The position of the first electrode may be set within a range of 4,700 Å to 5,400 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,050 Å to 2,750 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,850 Å to 3,550 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 4,450 Å to 5,000 Å from the first electrode.

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

A light emitting position of the first light emitting layer may be set in a range of 200 Å to 700 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,200 Å to 1,800 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,400 Å to 3,100 Å from the first electrode.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

The position of the first electrode may be set within a range of 4,700 Å to 5,400 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,050 Å to 2,750 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 3,350 Å to 3,950 Å from the second electrode.

An emission position of the first emission layer may be set within a range of 4,450 Å to 4,950 Å from the second electrode.

In addition, the white organic light emitting device according to the present invention includes a first organic layer and a first light emitting layer on a substrate, a second organic layer and a second light emitting layer on the first light emitting layer, and a third organic layer and a third light emitting layer on the second light emitting layer. a light emitting layer and a fourth organic layer on the third light emitting layer, regardless of at least one thickness of the first organic layer, the thickness of the second organic layer, the thickness of the third organic layer, or the thickness of the fourth organic layer; The second light emitting layer and the third light emitting layer have an EPEL (Emission Position of Emitting Layers) structure having a maximum light emitting range in the light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer, thereby increasing the luminous efficiency of the light emitting layer and a white organic light emitting diode capable of improving panel efficiency.

In the EPEL structure, regardless of the number of at least one first organic layer, the number of second organic layers, the number of third organic layers, and the number of fourth organic layers, the first light emitting layer, the second light emitting layer, and the third light emitting layer emit maximum light emission. It can be configured to have a range.

The EPEL structure may be configured so that the first light emitting layer, the second light emitting layer, and the third light emitting layer have a maximum light emitting range regardless of the thickness of the at least one first light emitting layer, the thickness of the second light emitting layer, and the thickness of the third light emitting layer. can

The EPEL structure is configured so that the first light emitting layer, the second light emitting layer, and the third light emitting layer have a maximum light emitting range regardless of the number of at least one first light emitting layer, the number of the second light emitting layer, and the number of the third light emitting layer. can

Other embodiment specifics are included in the detailed description and drawings.

By applying an EPEL (Emission Position of Emission Layers) structure in which the emission position of the light emitting layer corresponding to the light emitting region is set to the light emitting layer according to an embodiment of the present invention, the light emitting efficiency of the light emitting layer can be improved.

In addition, since the light emitting intensity of the light emitting layer is increased, there is an effect of improving panel efficiency and device lifetime.

In addition, the number of at least one light emitting layer, the thickness of the light emitting layer, the number of organic layers, the organic layer

By applying an Emission Position of Emission Layers (EPEL) structure regardless of the thickness of the organic light emitting device suitable for device structure or characteristics, device efficiency can be optimized.

In addition, since it is not necessary to use a polarizer, there is an effect of providing an organic light emitting display device with improved aperture ratio and luminance.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

Since the content of the invention described in the problem to be solved, the means for solving the problem, and the effect above does not specify the essential features of the claim, the scope of the claim is not limited by the matters described in the content of the invention.

1 is a schematic diagram showing a white organic light emitting device according to a first embodiment and a second embodiment of the present invention.
2 is a view showing a white organic light emitting diode according to a first embodiment of the present invention.
3 is a diagram showing a light emitting position of an organic light emitting device according to a first embodiment of the present invention.
4 is a diagram showing EL spectra according to a comparative example and a first embodiment of the present invention.
5 is a view showing a white organic light emitting device according to a second embodiment of the present invention.
6 is a diagram showing a light emitting position of an organic light emitting device according to a second embodiment of the present invention.
7 is a diagram showing EL spectra according to a comparative example and a second embodiment of the present invention.
8 is a view showing a white organic light emitting device according to a third embodiment of the present invention.
9 is a view showing a light emitting position of an organic light emitting device according to a third embodiment of the present invention.
10 is a diagram showing EL spectra according to a comparative example and a third embodiment of the present invention.
11 is a diagram illustrating an organic light emitting display device according to first to third exemplary embodiments of the present invention.
12 is a schematic diagram showing white organic light emitting diodes according to the fourth and fifth embodiments of the present invention.
13 is a view showing a white organic light emitting diode according to a fourth embodiment of the present invention.
14 is a diagram showing a light emitting position of an organic light emitting device according to a fourth embodiment of the present invention.
15 is a diagram showing an EL spectrum according to a fourth embodiment of the present invention.
16 is a view showing a white organic light emitting diode according to a fifth embodiment of the present invention.
17 is a diagram showing a light emitting position of an organic light emitting device according to a fifth embodiment of the present invention.
18 is a diagram showing an EL spectrum according to a fifth embodiment of the present invention.
19 is a view showing a white organic light emitting device according to a sixth embodiment of the present invention.
20 is a diagram showing a light emitting position of an organic light emitting device according to a sixth embodiment of the present invention.
21 is a diagram showing an EL spectrum according to a sixth embodiment of the present invention.
22 is a diagram illustrating organic light emitting display devices according to fourth to sixth embodiments of the present invention.
23 is a schematic diagram showing white organic light emitting diodes according to the seventh and eighth embodiments of the present invention.
24 is a view showing a white organic light emitting diode according to a seventh embodiment of the present invention.
25 is a diagram showing a light emitting position of an organic light emitting device according to a seventh embodiment of the present invention.
26 is a diagram showing an EL spectrum according to a seventh embodiment of the present invention.
27 is a view showing a white organic light emitting diode according to an eighth embodiment of the present invention.
28 is a view showing a light emitting position of an organic light emitting device according to an eighth embodiment of the present invention.
29 is a diagram showing an EL spectrum according to an eighth embodiment of the present invention.
30 is a view showing a white organic light emitting diode according to a ninth embodiment of the present invention.
31 is a view showing a light emitting position of an organic light emitting device according to a ninth embodiment of the present invention.
32 is a diagram showing an EL spectrum according to a ninth embodiment of the present invention.
33 is a diagram illustrating organic light emitting display devices according to seventh to ninth embodiments of the present invention.
34 is a schematic diagram showing a white organic light emitting device according to a tenth embodiment of the present invention.
35 is a view showing a white organic light emitting device according to a tenth embodiment of the present invention.
36 is a view showing a light emitting position of an organic light emitting device according to a tenth embodiment of the present invention.
37 is a diagram showing an EL spectrum according to a tenth embodiment of the present invention.
38 is a view showing a white organic light emitting device according to an 11th embodiment of the present invention.
39 is a view showing a light emitting position of an organic light emitting device according to an eleventh embodiment of the present invention.
40 is a diagram showing an EL spectrum according to an eleventh embodiment of the present invention.
41 is a diagram illustrating organic light emitting display devices according to tenth and eleventh embodiments of the present invention.

Advantages and features of the present invention, and methods of achieving them, will become clear with reference to the detailed description of the following embodiments taken in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only the present embodiments make the disclosure of the present invention complete, and common knowledge in the art to which the present invention belongs. It is provided to fully inform the holder of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative, so the present invention is not limited to the details shown. Like reference numbers designate like elements throughout the specification. In addition, in describing the present invention, if it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. When 'includes', 'has', 'consists of', etc. mentioned in this specification is used, other parts may be added unless 'only' is used. In the case where a component is expressed in the singular, the case including the plural is included unless otherwise explicitly stated.

In interpreting the components, even if there is no separate explicit description, it is interpreted as including the error range.

In the case of a description of a positional relationship, for example, 'on top of', 'on top of', 'at the bottom of', 'next to', etc. Or, unless 'directly' is used, one or more other parts may be located between the two parts.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal precedence relationship is described in terms of 'after', 'following', 'next to', 'before', etc. It can also include non-continuous cases unless is used.

Although first, second, etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from another. Therefore, the first component mentioned below may also be the second component within the technical spirit of the present invention.

Each feature of the various embodiments of the present invention can be partially or entirely combined or combined with each other, technically various interlocking and driving are possible, and each embodiment can be implemented independently of each other or can be implemented together in a related relationship. may be

Hereinafter, looking at the embodiments of the present invention in detail through the accompanying drawings and examples are as follows.

1 is a schematic diagram showing a white organic light emitting device according to a first embodiment and a second embodiment of the present invention.

The organic light emitting device is classified into a bottom emission method and a top emission method according to a transmission direction of emitted light. In the first to third embodiments of the present invention, a bottom emission method will be described as an example.

Here, the electroluminescence peak (EL peak) of the organic light emitting display device to which the organic light emitting element including the first, second, and third light emitting parts is applied is a photoluminescence peak (PhotoLuminescence Peak; It is determined by multiplying the PL peak) and the emission peak (EM Peak) of the organic layer constituting the organic light emitting device.

The white organic light emitting device 100 shown in FIG. 1 includes first and second electrodes 102 and 104, and a first light emitting unit 110 disposed between the first and second electrodes 102 and 104, and a second light emitting unit ( 120) and a third light emitting unit 130.

The first electrode 102 is an anode supplying holes and may be formed of a transparent conductive material such as transparent conductive oxide (TCO), indium tin oxide (ITO), indium zinc oxide (IZO), or the like. However, it is not necessarily limited thereto.

The second electrode 104 is a cathode supplying electrons and is formed of metallic materials such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), or an alloy thereof. It can be. However, it is not necessarily limited thereto.

The first electrode 102 and the second electrode 104 may be referred to as an anode or a cathode, respectively.

The first electrode may be a transmissive electrode, and the second electrode may be a reflective electrode.

The present invention configures the third light emitting part 130 including the first light emitting part 110, the second light emitting part 120, and the blue light emitting layer between the first electrode 102 and the second electrode 104 to produce blue light. (Blue) The luminous efficiency of the light emitting layer can be improved. And, the position of the first electrode 102 from the second electrode 104, the first light emitting layer of the first light emitting part 110, the second light emitting layer of the second light emitting part 120, and the third light emitting layer. The light emitting efficiency and panel efficiency are improved by setting the light emitting position of the third light emitting layer of the light emitting unit 130 . That is, an Emission Position of Emitting Layers (EPEL) structure is applied to the first light emitting layer, the second light emitting layer, and the third light emitting layer.

The position L0 of the first electrode 102 is set to be 4,500 Å to 6,000 Å away from the second electrode 104 . Alternatively, the position L0 of the first electrode 102 is set to be positioned within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104 . In addition, the emitting peak of the light emitting layer constituting the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 is located at a specific wavelength, and the light of the specific wavelength By emitting light, the luminous efficiency can be improved. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

The position L0 of the first electrode 102 is set from the second electrode 104, and the light emitting position L1 of the third light emitting part 130 closest to the second electrode 104 ) is set to be located within the range of 200 Å to 800 Å. Alternatively, the light emitting position L1 of the third light emitting part 130 is set to be positioned within a range of 200 Å to 800 Å from the reflective surface of the second electrode 104 . The third light emitting unit 130 may include a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer (Blue light emitting layer). ) and a green light emitting layer, or a combination thereof. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L1 of the third light emitting part 130 is 200 Å to 800 Å away from the second electrode 104. set to be within range. Alternatively, the light emitting position L1 of the third light emitting part 130 is set to be positioned within a range of 200 Å to 800 Å from the reflective surface of the second electrode 104 . Therefore, the emitting peak is a blue light emitting area, or a blue and yellow-green light emitting area, or a blue and red light emitting area, or a blue light emitting area. ) and a green light emitting region, and emits light of a wavelength corresponding to an emitting peak so that the third light emitting unit 130 can generate maximum luminance. A peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm.

In addition, the peak wavelength range of the blue light emitting layer and the yellow-green light emitting layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue light emitting layer and the red light emitting layer may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue light emitting layer and the green light emitting layer may be 440 nm to 560 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L2 of the second light emitting part 120 is set to be positioned within a range of 1,800 Å to 2,550 Å from the second electrode 104 . Alternatively, the light emitting position L2 of the second light emitting part 120 is set to be positioned within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104 . The second light emitting unit 120 may include a yellow-green light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a yellow-green ( It may consist of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L2 of the second light emitting part 120 is 1,800 Å to 2,550 Å from the second electrode 104 to be located within the range of Å. Alternatively, the light emitting position L2 of the second light emitting part 120 is set to be positioned within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104 . Therefore, the emission peak is located in the yellow-green emission region, or the yellow and red emission region, or the red and green emission region, or the yellow-green and red emission region, and the emission peak ( By emitting light of a wavelength corresponding to the emitting peak, the second light emitting unit 120 can generate maximum luminance. A peak wavelength range of the yellow-green light emitting layer may be 510 nm to 580 nm. And, the peak wavelength range of the yellow light emitting layer and the red light emitting layer may be 540 nm to 650 nm. In addition, the peak wavelength range of the red light emitting layer and the green light emitting layer may be 510 nm to 650 nm. In addition, the peak wavelength range of the yellow-green light emitting layer and the red light emitting layer may be 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L3 of the first light emitting part 110 is set to be 2,650 Å to 3,300 Å from the second electrode 104 . Alternatively, the light emitting position L3 of the first light emitting part 110 is set to be 2,650 Å to 3,300 Å from the reflective surface of the second electrode 104 . The first light emitting unit 110 may include a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer. It may consist of one of a light emitting layer and a green light emitting layer, or a combination thereof. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L3 of the first light emitting part 110 is 2,650 Å to 3,300 Å from the second electrode 104 Set it to be located within the range of Å. Alternatively, the light emitting position L3 of the first light emitting part 110 is set to be located within a range of 2,650 Å to 3,300 Å from the reflective surface of the second electrode 104 . Therefore, the emitting peak of the first light emitting part 110 is located in the blue light emitting region so that the first light emitting part 110 can emit maximum luminance. A peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, the peak wavelength range of the blue light emitting layer and the yellow-green light emitting layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue light emitting layer and the red light emitting layer may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue light emitting layer and the green light emitting layer may be 440 nm to 560 nm. Here, the peak wavelength may be a light emitting region.

The present invention sets the position of the first electrode 102 from the second electrode 104 regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of organic layers, and the number of organic layers, and the second An Emission Position of Emitting Layers (EPEL) structure in which light emission positions of the light emitting layers are set from the electrode 104 is applied.

2 is a view showing a white organic light emitting diode according to a first embodiment of the present invention.

The white organic light emitting device 100 shown in FIG. 2 includes first and second electrodes 102 and 104 and a first light emitting unit 110 and a second light emitting unit 120 between the first and second electrodes 102 and 104. and a third light emitting unit 130 .

The first electrode 102 and the second electrode 104 may be referred to as an anode or a cathode, respectively.

The position of the first electrode 102 is set to be 4,500 Å to 6,000 Å from the second electrode 104 . By setting the position (L0) of the first electrode 102, emission peaks of the light emitting layers constituting the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength. In addition, the first light emitting unit 110, the second light emitting unit 120, and the third light emitting unit 130 have a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. It has an EPEL (Emission Position of Emitting Layers) structure with

The third light emitting part 130 includes a third electron transporting layer (ETL) 136, a third emitting layer (EML) 134, and a third hole transporting layer under the second electrode 104. (HTL; Hole Transporting Layer) 132 may be included. Although not shown in the figure, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 136 . The electron injection layer (EIL) serves to inject electrons from the second electrode 104 into the third electron transport layer (ETL) 136 .

The third electron transport layer (ETL) 136 may be made of oxadiazole, triazole, phenanthroline, benzoxazole, or benzthiazole, It is not necessarily limited to this.

The third electron transport layer (ETL) 136 may be formed by applying two or more layers or two or more materials.

The third hole transport layer (HTL) 132 is TPD (N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) -benzidine) or NPB (N, N'-di (naphthalen- 1-yl) -N, N'-diphenyl-benzidine), etc., but is not necessarily limited thereto.

The third hole transport layer (HTL) 132 may be formed by applying two or more layers or two or more materials.

A hole injecting layer (HIL) may be further formed under the third hole transport layer (HTL) 132 . The hole injection layer (HIL) serves to inject holes from the second charge generation layer (CGL) 150 into the third hole transport layer (HTL) 132 .

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 134 . The hole blocking layer (HBL) prevents holes generated in the third light emitting layer (EML) 134 from passing over to the third electron transport layer (ETL) 136, thereby forming the third light emitting layer (EML) 134 The luminous efficiency of the third light emitting layer (EML) 134 may be improved by improving the coupling of electrons and holes in the . The third electron transport layer (ETL) 136 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the third light emitting layer (EML) 134 . The electron blocking layer (EBL) prevents electrons generated in the third light emitting layer (EML) 134 from passing over to the third hole transport layer (HTL) 132, so that the third light emitting layer (EML) 134 The luminous efficiency of the third light emitting layer (EML) 134 may be improved by improving the coupling of electrons and holes in the . The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 134 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 134 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) It is also possible to construct above or below (134).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 134 . have. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 134, the peak wavelength of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the third electron transport layer (ETL) 136, the third light emitting layer (EML) 134, the electron injection layer (EIL), and the hole blocking layer (HBL) may be referred to as organic layers. All organic layers between the second electrode 104 and the third light emitting layer (EML) 134 and the third light emitting layer (EML) 134 may be referred to as organic layers. Accordingly, all organic layers between the second electrode 104 and the third light emitting layer (EML) 134 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 136, regardless of the number or thickness of the third light emitting layer (EML) 134, or regardless of the number or thickness of the electron injection layer (EIL), Alternatively, regardless of the number or thickness of hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, the third light emitting layer ( The light emitting position (L1) of the EML (134) is set to be positioned within a range of 200 Å to 800 Å from the second electrode (104). Alternatively, the light emitting position L1 of the third light emitting layer (EML) 134 is set to be located within a range of 200 Å to 800 Å from the reflective surface of the second electrode 104 . Therefore, regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layers, and the thickness of the third light emitting layer, the light emitting position L1 of the third light emitting layer (EML) 134 ) may be set to be positioned within a range of 200 Å to 800 Å from the second electrode 104 . Alternatively, the light emitting position L1 of the third light emitting layer (EML) 134 regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layer, and the thickness of the third light emitting layer. ) may be set to be positioned within a range of 200 Å to 800 Å from the reflective surface of the second electrode 104 .

The second light emitting part 120 may include a second hole transport layer (HTL) 122 , a second light emitting layer (EML) 124 , and a second electron transport layer (ETL) 126 .

The second electron transport layer (ETL) 126 may be made of the same material as the third electron transport layer (ETL) 136, but is not necessarily limited thereto.

The second electron transport layer (ETL) 126 may be formed by applying two or more layers or two or more materials.

The second hole transport layer (HTL) 122 may be made of the same material as the third hole transport layer (HTL) 132, but is not necessarily limited thereto.

The second hole transport layer (HTL) 122 may be configured by applying two or more layers or two or more materials.

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 122 . The hole injection layer (HIL) serves to inject holes from the first charge transport layer (CGL) 140 into the second hole transport layer (HTL) 122 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 124 . The hole blocking layer (HBL) prevents holes generated in the second light emitting layer (EML) 124 from passing over to the second electron transport layer (ETL) 126, so that the second light emitting layer (EML) 124 The luminous efficiency of the second light emitting layer (EML) 124 may be improved by improving the coupling of electrons and holes in the . The second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 124 . The electron blocking layer (EBL) prevents electrons generated in the second light emitting layer (EML) 124 from passing over to the second hole transport layer (HTL) 122, so that the second light emitting layer (EML) 124 The luminous efficiency of the second light emitting layer (EML) 124 may be improved by improving the coupling of electrons and holes in the . The second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (124). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 124 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, peak wavelengths of the emission regions of the yellow emission layer and the red emission layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, the peak wavelength of the light emitting region of the red light emitting layer and the green light emitting layer may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 150 may be further formed between the second light emitting part 120 and the third light emitting part 130 . The second charge generating layer (CGL) 150 adjusts the charge balance between the second and third light emitting parts 120 and 130 . The second charge generation layer (CGL) 150 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The N-type charge generating layer serves to inject electrons into the second light emitting part 120, and the P-type charge generating layer serves to inject holes into the third light emitting part 130. .

The N-type charge generating layer (N-CGL) may be formed of an organic layer doped with an alkali metal such as Li, Na, K, or Cs, or an alkaline earth metal such as Mg, Sr, Ba, or Ra, respectively, but must be It is not limited.

Each of the P-type charge generating layers (P-CGL) may be formed of an organic layer including a P-type dopant, but is not necessarily limited thereto.

The second charge generating layer (CGL) 150 may be formed of a single layer.

The second light emitting layer (EML) 124, the second electron transport layer (ETL) 126, the second charge generation layer (CGL) 150, the third hole transport layer (HTL) 132, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124 and the second light emitting layer (EML) 124 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layer (HTL) 132, regardless of the number or thickness of the second charge generation layer (CGL) 150, or the second electron transport layer (ETL) 126 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the second light emitting layer (EML) 124, regardless of the number or thickness of the third light emitting layer (EML) 134, or the second electrode 104 and the third light emitting layer (EML) ) 134, regardless of the number or thickness of all organic layers, or regardless of the number or thickness of all organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124, The light emitting position L2 of the second light emitting layer (EML) 124 is set to be located within a range of 1,800 Å to 2,550 Å from the second electrode 104 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 124 is set to be positioned within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the light emitting position L2 of the second light emitting layer (EML) 124 may be set to be located within a range of 1,800 Å to 2,550 Å from the second electrode 104. have. Alternatively, regardless of the number of at least one of the fourth organic layers, the thickness of the fourth organic layer, the number of the third organic layers, the thickness of the third organic layer, the number of the third light emitting layers, and the thickness of the third light emitting layer, Regardless of the number of the second light emitting layers and the thickness of the second light emitting layer, the light emitting position L2 of the second light emitting layer (EML) 124 is 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104. It can be set to be located within the range.

The first light-emitting part 110 includes a first hole transport layer (HTL) 112, a first light-emitting layer (EML) 114, and a first electron transport layer (ETL) 116 on the first electrode 102. It can be done by

Although not shown in the drawings, a hole injection layer (HIL) may be additionally configured. The hole injection layer HIL is formed on the first electrode 102 and serves to smoothly inject holes from the first electrode 102 . The first hole transport layer (HTL) 112 supplies holes from the hole injection layer (HIL) to the first light emitting layer (EML) 114 . The first electron transport layer (ETL) 116 supplies electrons from the second electrode 104 to the first light emitting layer (EML) 114 .

The hole injection layer (HIL) is made of MTDATA (4,4',4"-tris(3-methylphenylphenylamino)triphenylamine), CuPc (copper phthalocyanine), or PEDOT/PSS (poly(3,4-ethylenedioxythiphene, polystyrene sulfonate), etc. It can be made, but is not necessarily limited thereto.

In the first light emitting layer (EML) 114, holes supplied through the first hole transport layer (HTL) 112 and electrons supplied through the first electron transport layer (ETL) 116 recombine. so light is generated.

The first electron transport layer (ETL) 116 may be made of the same material as the third electron transport layer (ETL) 136, but is not necessarily limited thereto.

The first electron transport layer (ETL) 116 may be formed by applying two or more layers or two or more materials.

The first hole transport layer (HTL) 112 may be made of the same material as the third hole transport layer (HTL) 132, but is not necessarily limited thereto.

The first hole transport layer (HTL) 112 may be formed by applying two or more layers or two or more materials.

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 114 . The hole blocking layer (HBL) prevents holes generated in the first light emitting layer (EML) 114 from passing over to the first electron transport layer (ETL) 116, thereby forming the first light emitting layer (EML) 114 The luminous efficiency of the first light emitting layer (EML) 114 may be improved by improving the coupling of electrons and holes in the . The first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 114 . The electron blocking layer (EBL) prevents electrons generated in the first light emitting layer (EML) 114 from passing over to the first hole transport layer (HTL) 112, so that the first light emitting layer (EML) 114 The luminous efficiency of the first light emitting layer (EML) 114 may be improved by improving the coupling of electrons and holes in the . The first hole transport layer (HTL) 112 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 114 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the first light emitting layer (EML) 114 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) ( 114) is also possible. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer may be formed identically or differently above and below the first light emitting layer (EML) 114 . can The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 114, the peak wavelength of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 140 may be further formed between the first light emitting part 110 and the second light emitting part 120 . The first charge generating layer (CGL) 140 adjusts the charge balance between the first and second light emitting parts 110 and 120 . The first charge generating layer (CGL) 140 may include an N-type charge generating layer and a P-type charge generating layer.

The N-type charge generating layer serves to inject electrons into the first light emitting part 110, and the P-type charge generating layer serves to inject holes into the second light emitting part 120. .

The first charge generating layer (CGL) 140 may be made of the same material as the N-type charge generating layer and the P-type charge generating layer of the second charge generating layer (CGL) 150, but is not necessarily limited thereto. not.

The first charge generating layer (CGL) 140 may be composed of a single layer.

The first light emitting layer (EML) 114, the first electron transport layer (ETL) 116, the first charge generation layer (CGL) 140, the second hole transport layer (HTL) 122, hole blocking All layers such as HBL, electron blocking layer (EBL), and hole injection layer (HIL) can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 and the first light emitting layer (EML) 114 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 may be referred to as a second organic layer.

Regardless of the number or thickness of the second hole transport layer (HTL) 122, regardless of the number or thickness of the first charge generation layer (CGL) 140, or regardless of the number or thickness of the electron blocking layer (EBL) without, or regardless of the number or thickness of the hole injection layer (HIL), or regardless of the number or thickness of the hole blocking layer (HBL), regardless of the number or thickness of the first electron transport layer (ETL) 116, or the Regardless of the number or thickness of the first light emitting layer (EML) 114, regardless of the number or thickness of the second light emitting layer (EML) 124, or regardless of the number or thickness of the third light emitting layer (EML) 134 without, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, or the third light emitting layer (EML) 134 and the second light emitting layer ( Regardless of the number or thickness of all organic layers between the EML (124), or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 , The light emitting position L3 of the first light emitting layer (EML) 114 is set to be located within a range of 2,650 Å to 3,300 Å from the second electrode 104 . Alternatively, the light emitting position L3 of the first light emitting layer (EML) 114 is set to be positioned within a range of 2,650 Å to 3,300 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the first light emitting layer (EML) 114 ) may be set to be positioned within a range of 2,650 Å to 3,300 Å from the second electrode 104 . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the first light emitting layer (EML) 114 ) may be set to be positioned within a range of 2,650 Å to 3,300 Å from the reflective surface of the second electrode 104 .

In addition, the first hole transport layer (HTL) 112, the electron blocking layer (EBL), the hole injection layer (HIL), etc. between the first light emitting layer (EML) 114 and the substrate 101 are called organic layers. can do. Accordingly, all layers including the first electrode 102 and between the first light emitting layer (EML) 114 and the substrate 101 may be referred to as organic layers. All organic layers and the first electrode 102 between the first light emitting layer (EML) 114 and the substrate 101 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 112, regardless of the number or thickness of the hole injection layer (HIL), regardless of the number or thickness of the electron blocking layer (EBL), or the first Regardless of the number or thickness of the electrodes 102, regardless of the number or thickness of the first light emitting layer (EML) 114, regardless of the number or thickness of the second light emitting layer (EML) 124, or regardless of the number or thickness of the second light emitting layer (EML) 124, or Regardless of the number or thickness of the third light emitting layer (EML) 134, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, or the third light emitting layer (EML) 134 Regardless of the number or thickness of all organic layers between the light emitting layer (EML) 134 and the second light emitting layer (EML) 124, or between the second light emitting layer (EML) 124 and the first light emitting layer (EML) ( 114) of the first electrode 102 regardless of the number or thickness of all organic layers interposed therebetween or regardless of the number or thickness of all organic layers interposed between the first light emitting layer (EML) 114 and the substrate 101. The position L0 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the second electrode 104 . Alternatively, the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. The number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, the thickness of the first light emitting layer, the number of the first organic layer, the first organic layer Regardless of the thickness of , the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the second electrode 104 . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. The number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, the thickness of the first light emitting layer, the number of the first organic layer, the first organic layer Regardless of the thickness of , the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104 .

Regardless of at least one of the thickness of light emitting layers, the number of light emitting layers, the thickness of organic layers, and the number of organic layers constituting the first light emitting unit 110, the second light emitting unit 120, and the third light emitting unit 130, It is a diagram explaining organic layers that may be formed between the first light emitting unit 110 , the second light emitting unit 120 , and the third light emitting unit 130 as an example. Therefore, it is not necessarily limited to this, and it is possible to selectively arrange according to the configuration and characteristics of the device.

The structure shown in FIG. 2 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the organic light emitting device, but is not limited thereto.

3 is a diagram showing a light emitting position of an organic light emitting device according to a first embodiment of the present invention.

That is, in FIG. 3, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the second electrode 104, which can be referred to as a contour map. Here, except for the first electrode 102 and the second electrode 104, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers. In FIG. 3, the light emitting positions of the light emitting layers are shown with the thickness of all organic layers excluding the first electrode 102 and the second electrode 104 being 4,200 Å. The thickness of the entire organic layers is not intended to limit the content of the present invention.

Since the third light emitting layer (EML) 134 constituting the third light emitting part 130 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may range from 440 nm to 480 nm. The maximum efficiency can be obtained when light is emitted in a white area of a contour map at 460 nm, which is the maximum wavelength (B-Max) of the blue light emitting layer.

Therefore, by setting the emission position 134E of the third light emitting layer (EML) 134 from the second electrode 104 to a range of 200 Å to 800 Å, the emission peak of the third light emitting layer (EML) 134 (Emitting Peak) ) (134E) is positioned at 460 nm, which is the maximum wavelength (B-Max). As a result, the third light emitting layer (EML) 134 emits light at 460 nm, which is the maximum wavelength (B-Max), so that maximum efficiency can be achieved. As already described, in FIG. 3, the light emitting position of the third light emitting layer (EML) 134 is shown as 3,400 Å to 4,000 Å, but this is a value obtained by subtracting 3,400 Å to 4,000 Å from 4,200 Å, which is the thickness of all organic layers. . Accordingly, the light emitting position of the third light emitting layer (EML) 134 may be in the range of 200 Å to 800 Å. This may be equally applied to the light emitting position of the second light emitting layer (EML) 124 and the light emitting position of the first light emitting layer (EML) 114 .

And, as the third light emitting layer (EML) 134, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) When composed of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

Since the second light emitting layer (EML) 124 constituting the second light emitting part 120 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved only when the maximum wavelength (YG-Max) of the yellow-green light emitting layer is 560 nm and light is emitted in a white region of a contour map.

Therefore, by setting the emission position of the second light emitting layer (EML) 124 from the second electrode 104 to the range of 1,800 Å to 2,550 Å, the emission peak of the second light emitting layer (EML) 124 (124E) is located at 560 nm, which is the maximum wavelength (YG-Max). As a result, the second light emitting layer (EML) 124 emits light at 560 nm, which is the maximum wavelength (YG-Max), so that maximum efficiency can be achieved.

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 540 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 124, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm.

Since the first light emitting layer (EML) 114 constituting the first light emitting part 110 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may range from 440 nm to 480 nm. The maximum efficiency can be achieved only when the maximum wavelength (B-Max) of the blue light emitting layer is 460 nm and light is emitted in a white region of a contour map.

Therefore, by setting the light emitting position of the first light emitting layer (EML) 114 from the second electrode 104 to a range of 2,650 Å to 3,300 Å, the emission peak 114E has a maximum wavelength (B-Max). ) at 460 nm. As a result, the first light emitting layer (EML) 114 emits light at 460 nm, which is the maximum wavelength (B-Max), so that maximum efficiency can be achieved.

And, as the first light emitting layer (EML) 114, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) In the case of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 114 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. Therefore, the present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer has a maximum emission range in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

In other words, by applying an EPEL (Emission Position of Emitting Layers) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength. .

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be a light emitting region.

Accordingly, the maximum emission range of the first emission layer may be 440 nm to 470 nm, the maximum emission range of the second emission layer may be 530 nm to 570 nm, and the maximum emission range of the third emission layer may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range. 4 is a diagram showing EL spectra according to a comparative example and a first embodiment of the present invention.

That is, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and as a comparative example, the emission intensity of the bottom emission type of the structure in which a blue light emitting layer and a yellow-green light emitting layer are laminated is shown. will be.

In FIG. 4, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 4 , the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 200 Å to 800 Å from the second electrode 104, the minimum position is set to 200 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 200 Å to 800 Å from the second electrode 104, the maximum position is set to 800 Å.

Example (optimum position) is the part set as the light emitting position of the first embodiment of the present invention. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 200 Å to 800 Å from the second electrode 104, the light emitting position in the embodiment is set in the range of 200 Å to 800 Å. .

As shown in FIG. 4 , in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the minimum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. Accordingly, the blue luminous efficiency is reduced. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of yellow-green light when set to the optimal position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of red light when set to the optimum position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment.

Efficiency of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied is shown in Table 1 below. When the efficiency of the comparative example is 100%, the efficiency of the first embodiment of the present invention is shown.

In Table 1 below, Comparative Example is a white organic light emitting device of a bottom emission method having a structure in which a blue light emitting layer and a yellow-green light emitting layer are stacked. In addition, the embodiment is a white organic light emitting device of a bottom emission method when the optimal position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied.

As shown in Table 1, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, if the efficiency of the comparative example is 100%, the green efficiency is increased by about 25%. Able to know. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 19%. It can be seen that the average efficiency is increased by about 20% compared to the comparative example.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 2 below.

Table 2 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 2, it can be seen that the efficiencies of red, green, blue, and white all decrease at the boundary between the example (minimum position) and the example (maximum position). have. In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the first embodiment of the present invention, the organic light emitting device may be a bottom emission type organic light emitting device.

The position of the first electrode may be set within a range of 4,500 Å to 6,000 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 200 Å to 800 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,800 Å to 2,550 Å from the second electrode.

A light emitting position of the first light emitting layer may be set within a range of 2,650 Å to 3,300 Å from the second electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

5 is a view showing a white organic light emitting device according to a second embodiment of the present invention.

The white organic light emitting device 100 shown in FIG. 5 includes first and second electrodes 102 and 104 and a first light emitting unit 110 and a second light emitting unit 120 between the first and second electrodes 102 and 104. and a third light emitting unit 130 . Hereinafter, in describing this embodiment, descriptions of components identical to or corresponding to those of the previous embodiment will be omitted. Set it to be at Å. In addition, the emission peaks of the light emitting layers constituting the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 are located at a specific wavelength, and the light of the specific wavelength Efficiency of the light emitting layers can be improved by emitting light. In addition, the first light emitting unit 110, the second light emitting unit 120, and the third light emitting unit 130 have a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. It has an EPEL (Emission Position of Emitting Layers) structure with

The third light emitting part 130 includes a third electron transport layer (ETL) 136, a third light emitting layer (EML) 134, and a third hole transport layer (HTL) 132 under the second electrode 104. can be made including

Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 136 . The electron injection layer (EIL) serves to inject electrons from the second electrode 104 into the third electron transport layer (ETL) 136 .

A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 132 .

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 134 . The third electron transport layer (ETL) 136 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the third light emitting layer (EML) 134 . The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 134 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 134 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) It is also possible to construct above or below (134).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 134 . have. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 134, the peak wavelength of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the third electron transport layer (ETL) 136, the third light emitting layer (EML) 134, the electron injection layer (EIL), and the hole blocking layer (HBL) may be referred to as organic layers. All organic layers between the second electrode 104 and the third light emitting layer (EML) 134 and the third light emitting layer (EML) 134 may be referred to as organic layers. Accordingly, all organic layers between the second electrode 104 and the third light emitting layer (EML) 134 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 136, regardless of the number or thickness of the third light emitting layer (EML) 134, or regardless of the number or thickness of the electron injection layer (EIL), Alternatively, regardless of the number or thickness of hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, the third light emitting layer (EML) ) 134 is set to be positioned within a range of 300 Å to 700 Å from the second electrode 104 . Alternatively, the light emitting position L1 of the third light emitting layer (EML) 134 is set to be positioned within a range of 300 Å to 700 Å from the reflective surface of the second electrode 104 . Therefore, regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layers, and the thickness of the third light emitting layer, the light emitting position L1 of the third light emitting layer (EML) 134 ) may be set to be located within 300 Å to 700 Å from the second electrode 104 . Alternatively, the light emitting position L1 of the third light emitting layer (EML) 134 regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layer, and the thickness of the third light emitting layer. ) may be set to be located within 300 Å to 700 Å from the reflective surface of the second electrode 104 .

The second light emitting part 120 may include a second hole transport layer (HTL) 122 , a second light emitting layer (EML) 124 , and a second electron transport layer (ETL) 126 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 122 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 124 . Also, the second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 124 . Also, the second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (124). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 124 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 124 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the second emission layer (EML) 124 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 124 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When the second light emitting layer (EML) 124 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 150 may be further formed between the second light emitting part 120 and the third light emitting part 130 . The second charge generation layer (CGL) 150 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The second light emitting layer (EML) 124, the second electron transport layer (ETL) 126, the second charge generation layer (CGL) 150, the third hole transport layer (HTL) 132, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124 and the second light emitting layer (EML) 124 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layer (HTL) 132, regardless of the number or thickness of the second charge generation layer (CGL) 150, or the second electron transport layer (ETL) 126 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the second light emitting layer (EML) 124, regardless of the number or thickness of the third light emitting layer (EML) 134, or the second electrode 104 and the third light emitting layer (EML) ) 134, regardless of the number or thickness of all organic layers, or regardless of the number or thickness of all organic layers between the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124, The light emitting position L2 of the second light emitting layer (EML) 124 is set to be located within a range of 1,900 Å to 2,400 Å from the second electrode 104 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 124 is set to be positioned within a range of 1,900 Å to 2,400 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the light emitting position L2 of the second light emitting layer (EML) 124 may be set to be located within a range of 1,900 Å to 2,400 Å from the second electrode 104. have. Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the light emitting position L2 of the second light emitting layer (EML) 124 is located within a range of 1,900 Å to 2,400 Å from the reflective surface of the second electrode 104. can be set to do so.

The first light-emitting part 110 includes a first hole transport layer (HTL) 112, a first light-emitting layer (EML) 114, and a first electron transport layer (ETL) 116 on the first electrode 102. It can be done by

Although not shown in the drawings, a hole injection layer (HIL) may be additionally configured. The hole injection layer HIL is disposed on the first electrode 102 and serves to smoothly inject holes from the first electrode 102 . A hole blocking layer (HBL) may be additionally formed on the first electron transport layer (ETL) 116 . Also, the first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as one layer.

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 114 . The first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 114 . Also, the first hole transport layer (HTL) 112 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 114 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the first light emitting layer (EML) 114 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) ( 114) is also possible. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer may be formed identically or differently above and below the first light emitting layer (EML) 114 . can The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 114, the peak wavelength of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 140 may be further formed between the first light emitting part 110 and the second light emitting part 120 . The first charge generating layer (CGL) 140 may include an N-type charge generating layer and a P-type charge generating layer.

The first light emitting layer (EML) 114, the first electron transport layer (ETL) 116, the first charge generation layer (CGL) 140, the second hole transport layer (HTL) 122, hole blocking All layers such as HBL, electron blocking layer (EBL), and hole injection layer (HIL) can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 and the first light emitting layer (EML) 114 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 may be referred to as a second organic layer.

Regardless of the number or thickness of the second hole transport layer (HTL) 122, regardless of the number or thickness of the first charge generation layer (CGL) 140, or regardless of the number or thickness of the electron blocking layer (EBL) without, or regardless of the number or thickness of the hole injection layer (HIL), or regardless of the number or thickness of the hole blocking layer (HBL), regardless of the number or thickness of the first electron transport layer (ETL) 116, or the Regardless of the number or thickness of the first light emitting layer (EML) 114, regardless of the number or thickness of the second light emitting layer (EML) 124, or regardless of the number or thickness of the third light emitting layer (EML) 134 without, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, or the third light emitting layer (EML) 134 and the second light emitting layer ( Regardless of the number or thickness of all organic layers between the EML (124), or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 , The light emitting position L3 of the first light emitting layer (EML) 114 is set to be positioned within a range of 2,800 Å to 3,200 Å from the second electrode 104 . Alternatively, the light emitting position L3 of the first light emitting layer (EML) 114 is set to be positioned within a range of 2,800 Å to 3,200 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the first light emitting layer (EML) 114 ) may be set to be located within a range of 2,800 Å to 3,200 Å from the second electrode 104 . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the first light emitting layer (EML) 114 ) may be set to be located within a range of 2,800 Å to 3,200 Å from the reflective surface of the second electrode 104 .

In addition, the first hole transport layer (HTL) 112, the electron blocking layer (EBL), the hole injection layer (HIL), etc. between the first light emitting layer (EML) 114 and the substrate 101 are called organic layers. can do. Therefore, all layers between the first light emitting layer (EML) 114 and the substrate 101 and including the first electrode 102 may be referred to as organic layers, and the first light emitting layer (EML) 114 All organic layers and the first electrode 102 between the substrate 101 and the substrate 101 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 112, regardless of the number or thickness of the hole injection layer (HIL), regardless of the number or thickness of the electron blocking layer (EBL), or the first Regardless of the number or thickness of the electrodes 102, regardless of the number or thickness of the first light emitting layer (EML) 114, regardless of the number or thickness of the second light emitting layer (EML) 124, or regardless of the number or thickness of the second light emitting layer (EML) 124, or Regardless of the number or thickness of the third light emitting layer (EML) 134, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third light emitting layer (EML) 134, or the third light emitting layer (EML) 134 Regardless of the number or thickness of all organic layers between the light emitting layer (EML) 134 and the second light emitting layer (EML) 124, or between the second light emitting layer (EML) 124 and the first light emitting layer (EML) ( 114) regardless of the number or thickness of all organic layers interposed therebetween or regardless of the number or thickness of all organic layers interposed between the first light emitting layer (EML) 114 and the substrate 101, the first electrode 102 The position L0 of may be set to be positioned within a range of 4,500 Å to 6,000 Å from the second electrode 104 . Alternatively, the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. The number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, the thickness of the first light emitting layer, the number of the first organic layer, the first organic layer Regardless of the thickness of , the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the second electrode 104 . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. The number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, the thickness of the first light emitting layer, the number of the first organic layer, the first organic layer Regardless of the thickness of , the position L0 of the first electrode 102 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104 .

The structure shown in FIG. 5 shows an example of the present invention, and can be selectively configured according to the structure or characteristics of the organic light emitting device, but is not limited thereto.

6 is a diagram showing a light emitting position of an organic light emitting device according to a second embodiment of the present invention.

That is, in FIG. 6, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the second electrode 104, which can be referred to as a contour map. Here, except for the first electrode 102 and the second electrode 104, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers. In FIG. 6, the light emitting positions of the light emitting layers are shown with the thickness of all organic layers excluding the first electrode 102 and the second electrode 104 being 4,200 Å. The thickness of the entire organic layers is not intended to limit the content of the present invention.

Since the third light emitting layer (EML) 134 constituting the third light emitting part 130 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may range from 440 nm to 480 nm. The maximum efficiency can be obtained when light is emitted in a white area of a contour map at 460 nm, which is the maximum wavelength (B-Max) of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 134 in the range of 300 Å to 700 Å, the emission peak 134E of the third light emitting layer (EML) 134 is the maximum wavelength (B-Max). ) at 460 nm. Therefore, maximum efficiency can be achieved by emitting light at 460 nm, which is the maximum wavelength (B-Max), from the third light emitting layer (EML) 134 . In FIG. 6 , the emission position 134E of the third light emitting layer (EML) 134 is shown as 3,500 Å to 3,900 Å, but this is a value obtained by subtracting 3,500 Å to 3,900 Å from 4,200 Å, which is the thickness of all organic layers. Accordingly, the light emitting position of the third light emitting layer (EML) 134 may be in the range of 200 Å to 800 Å. This may be equally applied to the light emitting position of the second light emitting layer (EML) 124 and the light emitting position of the first light emitting layer (EML) 114 .

And, as the third light emitting layer (EML) 134, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) When composed of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

Since the second light emitting layer (EML) 124 constituting the second light emitting part 120 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved only when the maximum wavelength (YG-Max) of the yellow-green light emitting layer is 560 nm and light is emitted in a white region of a contour map.

Therefore, by setting the light emitting position of the second light emitting layer (EML) 124 in the range of 1,900 Å to 2,400 Å, the emission peak 124E corresponding to the light emitting region of the second light emitting layer (EML) 124 is positioned at the maximum wavelength (YG-Max) of 560 nm. Therefore, maximum efficiency can be achieved by emitting light at 560 nm, which is the maximum wavelength (YG-Max), from the second light emitting layer (EML) 124 .

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 540 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 124, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm.

Since the first light emitting layer (EML) 114 constituting the first light emitting part 110 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may range from 440 nm to 480 nm. The maximum efficiency can be achieved only when the maximum wavelength (B-Max) of the blue light emitting layer is 460 nm and light is emitted in a white region of a contour map.

Therefore, the emission position of the first light emitting layer (EML) 114 is set in the range of 2,800 Å to 3,200 Å so that the emission peak 114E is located at 460 nm, which is the maximum wavelength (B-Max). . Therefore, maximum efficiency can be achieved by emitting light at 460 nm, which is the maximum wavelength (B-Max), from the first light emitting layer (EML) 114 .

And, as the first light emitting layer (EML) 114, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) In the case of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. Therefore, the present invention applies an Emission Position of Emitting Layers (EPEL) structure so that the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

In other words, by applying the EPEL (Emission Position of Emitting Layers) structure to the light emitting layer, the emitting peak is located at a specific wavelength, so that the light emitting layers can achieve maximum efficiency in the light of the wavelength corresponding to the specific wavelength. there will be

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be a light emitting region. Accordingly, the maximum emission range of the first emission layer may be 440 nm to 470 nm, the maximum emission range of the second emission layer may be 530 nm to 570 nm, and the maximum emission range of the third emission layer may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

7 is a diagram showing EL spectra according to a comparative example and a second embodiment of the present invention.

That is, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and as a comparative example, the emission intensity of the bottom emission type of the structure in which a blue light emitting layer and a yellow-green light emitting layer are laminated is shown. will be.

In FIG. 7, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 7 , the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 300 Å to 700 Å from the second electrode 104, the minimum position is set to 300 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 300 Å to 700 Å from the second electrode 104, the maximum position is set to 700 Å.

Example (optimum position) is the part set as the light emitting position of the first embodiment of the present invention. For example, when the light emitting position L1 of the third light emitting layer (EML) 134 is in the range of 300 Å to 700 Å from the second electrode 104, the light emitting position in the embodiment is set to the range of 300 Å to 700 Å. .

As shown in FIG. 7 , in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the minimum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the luminescence intensity decreases in the peak wavelength range of 510 nm to 580 nm, which is the peak wavelength range of yellow-green light, and is out of the peak wavelength range of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. Accordingly, the blue luminous efficiency is reduced. And, it can be seen that the luminescence intensity decreases in the peak wavelength range of 510 nm to 580 nm, which is the peak wavelength range of yellow-green light, and is out of the peak wavelength range of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of yellow-green light when set to the optimal position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of red light when set to the optimum position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment.

Efficiency of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied is shown in Table 3 below. When the efficiency of the comparative example is 100%, the efficiency of the second embodiment of the present invention is shown.

In Table 3 below, Comparative Example is a white organic light emitting device of a bottom emission method having a structure in which a blue light emitting layer and a yellow-green light emitting layer are stacked. In addition, the embodiment is a white organic light emitting device of a bottom emission method when the optimal position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied.

As shown in Table 3, if the efficiency of the comparative example is 100% when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, the green efficiency is increased by about 25%. Able to know. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 19%. It can be seen that the average efficiency is increased by about 20% compared to the comparative example.

Table 4 below shows the panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example.

Table 4 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimal position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 4, it can be seen that the efficiencies of green, blue, and white all decrease at the boundary between the embodiment (minimum position) and the embodiment (maximum position). And, comparing Table 2 of the first embodiment of the present invention with Table 4 of the second embodiment of the present invention, green and blue colors are displayed at the boundary between the embodiment (minimum position) and the embodiment (maximum position). ) and white efficiency were further improved. Accordingly, according to the second exemplary embodiment of the present invention, an organic light emitting display device with further improved efficiency can be provided. In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the second embodiment of the present invention, the organic light emitting device may be a bottom emission type organic light emitting device.

The position of the first electrode may be set within a range of 4,500 Å to 6,000 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 300 Å to 700 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,900 Å to 2,400 Å from the second electrode.

A light emitting position of the first light emitting layer may be set within a range of 2,800 Å to 3,200 Å from the second electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

8 is a view showing a white organic light emitting device according to a third embodiment of the present invention.

In this embodiment, the light emitting position of the light emitting layers is set from the first electrode, and the light emitting position can be set from the first electrode according to device design.

The position of the second electrode 104 is set to be positioned within a range of 4,500 Å to 6,000 Å from the first electrode 102 . In addition, the emission peaks of the light emitting layers constituting the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 are located at a specific wavelength, and the light of the specific wavelength Efficiency of the light emitting layers can be improved by emitting light. In addition, the first light emitting part, the second light emitting part, and the third light emitting part have a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer (EPEL) (Emission Position of Emitting Layers) to have a structure.

The first light-emitting part 110 includes a first hole transport layer (HTL) 112, a first light-emitting layer (EML) 114, and a first electron transport layer (ETL) 116 on the first electrode 102. It can be done by

Although not shown in the drawings, a hole injection layer (HIL) may be additionally configured. The hole injection layer HIL is disposed on the first electrode 102 and serves to smoothly inject holes from the first electrode 102 . A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 114 . Also, the first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 114 . Also, the first hole transport layer (HTL) 112 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 114 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the first light emitting layer (EML) 114 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) ( 114) is also possible. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer may be formed identically or differently above and below the first light emitting layer (EML) 114 . can The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 114, the peak wavelength of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 112, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the substrate 101 and the first light emitting layer (EML) 114 and the first electrode 102 may be referred to as organic layers. Accordingly, all organic layers between the substrate 101 and the first light emitting layer (EML) 114 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 112, or regardless of the number or thickness of the first electrodes 102, or regardless of the number or thickness of the electron blocking layers (EBL), or hole injection The first light emitting layer (EML) 114 regardless of the number or thickness of layers HIL or regardless of the number or thickness of all organic layers between the substrate 101 and the first light emitting layer (EML) 114 The light emitting position L1 of is set to be positioned within a range of 2,000 Å to 2,650 Å from the first electrode 102 . Alternatively, the light emitting position L3 of the first light emitting layer (EML) 114 may be set to be located within a range of 2,000 Å to 2,650 Å from the interface between the substrate 101 and the first electrode 102.

Therefore, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 114 is 2,000 Å to 2,650 Å from the first electrode 102 It can be set to be located within the range of Å. Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 114 is the substrate 101 and the first electrode 102 ) from the interface of 2,000 Å to 2,650 Å can be set to be located.

The second light emitting part 120 may include a second hole transport layer (HTL) 122 , a second light emitting layer (EML) 124 , and a second electron transport layer (ETL) 126 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 122 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 124 . Also, the second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 124 . Also, the second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (124). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 124 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 124 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the second emission layer (EML) 124 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When the second light emitting layer (EML) 124 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, luminous efficiency of the red light emitting layer may be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 140 may be further formed between the first light emitting part 110 and the second light emitting part 120 . The first charge generating layer (CGL) 140 may include an N-type charge generating layer and a P-type charge generating layer.

The first light emitting layer (EML) 114, the first electron transport layer (ETL) 116, the first charge generation layer (CGL) 140, the second hole transport layer (HTL) 122, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first light emitting layer (EML) 114 and the second light emitting layer (EML) 124 and the first light emitting layer (EML) 114 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 114 and the second light emitting layer (EML) 124 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 116, regardless of the number or thickness of the second hole transport layer (HTL) 122, or the first charge generating layer (CGL) 140 Regardless of the number or thickness, or the number or thickness of hole blocking layers (HBL), or the number or thickness of electron blocking layers (EBL), or the number or thickness of hole injection layers (HIL), or the above Regardless of the number or thickness of the first light emitting layer (EML) 114, or regardless of the number or thickness of all organic layers between the substrate 101 and the first light emitting layer (EML) 114, or the first light emitting layer Regardless of the number or thickness of all organic layers between the (EML) 114 and the second light emitting layer (EML) 124, the light emitting position L2 of the second light emitting layer (EML) 124 is the first electrode (102) to be located within the range of 2,750 Å to 3,500 Å. Alternatively, the light emitting position L2 of the second light emitting layer (EML) 124 may be set to be positioned within a range of 2,750 Å to 3,500 Å from the interface between the substrate 101 and the first electrode 102.

Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The light emitting position L2 of the second light emitting layer (EML) 124 may be set to be located within a range of 2,750 Å to 3,500 Å from the first electrode 102 . Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The light emitting position L2 of the second light emitting layer (EML) 124 may be set to be positioned within a range of 2,750 Å to 3,500 Å from the interface between the substrate 101 and the first electrode 102 .

The third light emitting part 130 includes a third electron transport layer (ETL) 136, a third light emitting layer (EML) 134, and a third hole transport layer (HTL) 132 under the second electrode 104. can be made including

Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 136 . A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 132 . A hole blocking layer (HBL) may be further formed over the third light emitting layer (EML) 134 . have. The third electron transport layer (ETL) 136 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the third light emitting layer (EML) 134 . The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 134 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 134 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) It is also possible to construct above or below (134). In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 134 . have. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 134, the peak wavelength of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 150 may be further formed between the second light emitting part 120 and the third light emitting part 130 . The second charge generation layer (CGL) 150 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The second light emitting layer (EML) 124, the second electron transport layer (ETL) 126, the third hole transport layer (HTL) 132, the second charge generation layer (CGL) 150, the hole injection layer (HIL), electron blocking layer (EBL), hole blocking layer (HBL) and the like can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 124 and the third light emitting layer (EML) 134 and the second light emitting layer (EML) 124 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 124 and the third light emitting layer (EML) 134 may be referred to as a third organic layer.

Regardless of the number or thickness of the second light emitting layer (EML) 124, regardless of the number or thickness of the second electron transport layer (ETL) 126, or the number or thickness of the third hole transport layer (HTL) 132 Regardless of the number or thickness of the second charge generation layer (CGL) 150, regardless of the number or thickness of the hole injection layer (HIL), or regardless of the number or thickness of the electron blocking layer (EBL) without, or regardless of the number or thickness of the hole blocking layer (HBL), or regardless of the number or thickness of the first light emitting layer (EML) 114, or the substrate 101 and the first light emitting layer (EML) 114 ) Regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 114 and the second light emitting layer (EML) 124, regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 114 and the second light emitting layer (EML) 124, or Regardless of the number or thickness of all organic layers between the second light-emitting layer (EML) 124 and the third light-emitting layer (EML) 134, the light-emitting position L3 of the third light-emitting layer (EML) 134 is the first light-emitting layer (EML) 134. It is set to be positioned within the range of 4,500 Å to 5,100 Å from the electrode 102 . Alternatively, the light emitting position L3 of the third light emitting layer (EML) 134 may be set to be positioned within a range of 4,500 Å to 5,100 Å from the interface between the substrate 101 and the first electrode 102.

Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Regardless of the number of light-emitting layers, the thickness of the first light-emitting layer, the number of second light-emitting layers, and the thickness of the second light-emitting layer, the light-emitting position L3 of the third light-emitting layer (EML) 134 is the first electrode 102 ) from 4,500 Å to 5,100 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layers, and the thickness of the second light emitting layer, the light emitting position L3 of the third light emitting layer (EML) 134 is relative to the substrate 101 It may be set to be positioned within a range of 4,500 Å to 5,100 Å from the interface of the first electrode 102 .

In addition, all layers such as the third light emitting layer (EML) 134, the third electron transport layer (ETL) 136, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 134 and the second electrode 104 and the third light emitting layer (EML) 134 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 134 and the second electrode 104 may be referred to as a first organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 136, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the third Regardless of the number or thickness of the light emitting layers (EML) 134, regardless of the number or thickness of the second light emitting layers (EML) 124, or regardless of the number or thickness of the first light emitting layer (EML) 114, Alternatively, regardless of the number or thickness of all organic layers between the substrate 101 and the first light emitting layer (EML) 114, or the first light emitting layer (EML) 114 and the second light emitting layer (EML) 124 ) Regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 124 and the third light emitting layer (EML) 134, regardless of the number or thickness of all organic layers, or 3 Regardless of the thickness of all organic layers between the light emitting layer (EML) 134 and the second electrode 104, the position L0 of the second electrode 104 is 4,500 Å away from the first electrode 102. to 6,000 Å. Alternatively, the position L0 of the second electrode 104 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the interface between the substrate 101 and the first electrode 102 .

Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 104 may be set to be located within a range of 4,500 Å to 6,000 Å from the first electrode 102 regardless of the thickness of the . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer Regardless of the thickness of , the position L0 of the second electrode 104 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the interface between the substrate 101 and the first electrode 102 .

Here, the light emitting position L3 of the third light emitting layer (EML) 134 may be set to be positioned within a range of 4,500 Å to 5,100 Å from the first electrode 102 . Also, the position L0 of the second electrode 104 may be set to be positioned within a range of 4,500 Å to 6,000 Å from the first electrode 102 . When the light emitting position L3 of the third light emitting layer (EML) 134 is set to 4,500 Å from the first electrode 102, the position L0 of the second electrode 104 is the first electrode ( 102), it can be set to be located within the range of 4,550 Å to 6,000 Å. When the light emitting position L3 of the third light emitting layer (EML) 134 is set to 5,100 Å from the first electrode 102, the position L0 of the second electrode 104 is the first position L0 of the first electrode 102. It may be set to be positioned within a range of 5,150 Å to 6,000 Å from the electrode 102 .

Accordingly, the present invention provides at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, The number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, Regardless of the thickness of the third light emitting layer, the position of the second electrode 104 from the first electrode 102 and the position of the light emitting layers can be set.

The structure shown in FIG. 8 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the organic light emitting device, but is not limited thereto.

9 is a view showing a light emitting position of an organic light emitting device according to a third embodiment of the present invention.

That is, in FIG. 9, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 102, which can be referred to as a contour map. Here, except for the second electrode 104, when the EPEL structure of the present invention is applied, the light emitting positions of the light emitting layers at the emitting peak are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers. Since the first light emitting layer (EML) 114 constituting the first light emitting part 110 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may range from 440 nm to 480 nm. The maximum efficiency can be achieved only when the maximum wavelength (B-Max) of the blue light emitting layer is 460 nm and light is emitted in a white region of a contour map.

Therefore, the emission position of the first light emitting layer (EML) 114 is set in the range of 2,000 Å to 2,650 Å so that the emission peak 114E is located at 460 nm, which is the maximum wavelength (B-Max). . Therefore, maximum efficiency can be achieved by emitting light at 460 nm, which is the maximum wavelength (B-Max), from the first light emitting layer (EML) 114 .

And, as the first light emitting layer (EML) 114, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) In the case of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 114 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

Since the second light emitting layer (EML) 124 constituting the second light emitting part 120 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved only when the maximum wavelength (YG-Max) of the yellow-green light emitting layer is 560 nm and light is emitted in a white region of a contour map.

Therefore, by setting the light emitting position of the second light emitting layer (EML) 124 in the range of 2,750 Å to 3,500 Å, the emission peak 124E corresponding to the light emitting region of the second light emitting layer (EML) 124 is positioned at the maximum wavelength (YG-Max) of 560 nm. Therefore, maximum efficiency can be achieved by emitting light at 560 nm, which is the maximum wavelength (YG-Max), from the second light emitting layer (EML) 124 .

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 540 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 124 of the second light emitting part 120 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 124 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 124, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm.

Since the third light emitting layer (EML) 134 constituting the third light emitting part 130 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may range from 440 nm to 480 nm. The maximum efficiency can be obtained when light is emitted in a white area of a contour map at 460 nm, which is the maximum wavelength (B-Max) of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 134 in the range of 4,500 Å to 5,100 Å, the emission peak 134E of the third light emitting layer (EML) 134 is the maximum wavelength (B -Max) at 460 nm. Therefore, maximum efficiency can be achieved by emitting light at 460 nm, which is the maximum wavelength (B-Max), from the third light emitting layer (EML) 134 .

And, as the third light emitting layer (EML) 134, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer (Green) When composed of one of the light emitting layers or a combination thereof, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 134 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. Therefore, the present invention applies an Emission Position of Emitting Layers (EPEL) structure so that the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

In other words, by applying the EPEL (Emission Position of Emitting Layers) structure to the light emitting layer, the emitting peak is located at a specific wavelength, so that the light emitting layers can achieve maximum efficiency in the light of the wavelength corresponding to the specific wavelength. there will be

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 440 nm to 470 nm, the maximum emission range of the second emission layer is 530 nm to 570 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

10 is a diagram showing EL spectra according to a comparative example and a third embodiment of the present invention.

That is, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and as a comparative example, the emission intensity of the bottom emission type of the structure in which a blue light emitting layer and a yellow-green light emitting layer are laminated is shown. In FIG. 10, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 10, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 114 is in the range of 2,000 Å to 2,650 Å from the first electrode 102, the minimum position is set to 2,000 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 114 is in the range of 2,000 Å to 2,650 Å from the first electrode 102, the maximum position is set to 2,650 Å.

Example (optimum position) is the part set as the light emitting position of the first embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 114 is in the range of 2,000 Å to 2,650 Å from the first electrode 102, the light emitting position in the embodiment is in the range of 2,000 Å to 2,650 Å. is set to

As shown in FIG. 10 , in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with an optimal position when the light emitting position deviate from the minimum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. And, it can be seen that it is out of the peak wavelength range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. Accordingly, the blue luminous efficiency is reduced. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of yellow-green light when set to the optimal position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment. In addition, it can be seen that the emission intensity increases in the peak wavelength range of red light when set to the optimum position of the present invention, compared to the case of setting to the minimum position or maximum position of the embodiment.

Efficiency of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied is shown in Table 5 below. When the efficiency of the comparative example is 100%, the efficiency of the third embodiment of the present invention is shown.

In Table 5 below, Comparative Example is a white organic light emitting device of a bottom emission method having a structure in which a blue light emitting layer and a yellow-green light emitting layer are stacked. In addition, the embodiment is a white organic light emitting device of a bottom emission method when the optimal position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied.

As shown in Table 5, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, if the efficiency of the comparative example is 100%, the green efficiency is increased by about 25%. Able to know. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 19%. It can be seen that the average efficiency is increased by about 20% compared to the comparative example.

Table 6 below shows the panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example.

Table 6 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimal position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 6, it can be seen that the red, green, blue, and white efficiencies all decrease at the boundary between the example (minimum position) and the example (maximum position). have. In addition, it can be seen that the efficiency of red, green, blue, and white is more reduced in the embodiment (maximum position) than in the embodiment (minimum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the third embodiment of the present invention, the organic light emitting device may be a bottom emission type organic light emitting device.

The position of the second electrode may be set within a range of 4,500 Å to 6,000 Å from the first electrode.

A light emitting position of the first light emitting layer may be set within a range of 2,000 Å to 2,650 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,750 Å to 3,500 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 4,500 Å to 5,100 Å from the first electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

The organic light emitting device according to the present invention described above may be applied to a lighting device, may be used as a thin light source of a liquid crystal display device, or may be applied to a display device. Hereinafter, an embodiment in which the organic light emitting diode according to the present invention is applied to a display device will be described.

11 is a cross-sectional view of an organic light emitting display device including an organic light emitting device according to an embodiment of the present invention, which includes organic light emitting devices according to the first, second and third embodiments of the present invention described above. it was used

As shown in FIG. 11, an organic light emitting display device 1000 according to the present invention includes a substrate 10, a thin film transistor (TFT), an overcoating layer 1150, a first electrode 102, a light emitting unit 1180, and and a second electrode (104). The thin film transistor (TFT) includes a gate electrode 1115, a gate insulating layer 1120, a semiconductor layer 1131, a source electrode 1133 and a drain electrode 1135.

In FIG. 11, the thin film transistor (TFT) is shown as an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 10 may be made of glass, metal, or plastic.

A gate electrode 1115 is formed on the substrate 10 and connected to a gate line (not shown). The gate electrode 1115 is from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a multi-layer made of any selected one or an alloy thereof.

The gate insulating layer 1120 is formed on the gate electrode 1115 and may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto.

The semiconductor layer 1131 is formed on the gate insulating layer 1120, and includes amorphous silicon (a-Si), polycrystalline silicon (poly-Si), oxide semiconductor, or organic semiconductor. can be formed as When the semiconductor layer is formed of an oxide semiconductor, it may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), but is not limited thereto. An etch stopper (not shown) may be formed on the semiconductor layer 1131 to protect the semiconductor layer 1131, but may be omitted depending on the configuration of the device.

The source electrode 1133 and the drain electrode 1135 may be formed on the semiconductor layer 1131 . The source electrode 1133 and the drain electrode 1135 may be formed of a single layer or multiple layers, and may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), or nickel (Ni). ), any one selected from the group consisting of neodymium (Nd) and copper (Cu), or an alloy thereof.

The protective layer 1140 is formed on the source electrode 1133 and the drain electrode 1135, and may be formed of a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof. Alternatively, it may be formed of acrylic resin, polyimide resin, etc., but is not limited thereto.

A color filter 1145 is formed on the first protective layer 1140, and although only one sub-pixel is shown in the drawing, the color filter 1145 is applied to regions of a red sub-pixel, a blue sub-pixel, and a green sub-pixel. is formed The color filter 1145 includes a red (R) color filter, a green (G) color filter, and a blue (B) color filter patterned for each sub-pixel. The color filter 1145 transmits only light of a specific wavelength among the white light emitted from the light emitting unit 1180 .

The overcoating layer 1150 is formed on the color filter 1145 and may be an acrylic resin, a polyimide resin, an oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is limited thereto. It doesn't work.

The first electrode 102 is formed on the overcoating layer 1150. The first electrode 102 is formed on the drain through the passivation layer 1140 and the contact hole CH of a predetermined area of the overcoating layer 1150. It is electrically connected to the electrode 1135. 11 shows that the drain electrode 1135 and the first electrode 1102 are electrically connected, but the source electrode ( 1133) and the first electrode 102 may be electrically connected.

A bank layer 1170 is formed on the first electrode 102 and defines a pixel area. That is, the bank layer 1170 is formed in a matrix structure in a boundary area between a plurality of pixels, so that a pixel area is defined by the bank layer 1170 . The bank layer 1170 may be formed of an organic material such as benzocyclobutene (BCB)-based resin, acryl-based resin, or polyimide resin. Alternatively, the bank layer 1170 may be formed of a photoresist containing a black pigment. In this case, the bank layer 1170 serves as a light blocking member.

The light emitting part 1180 is formed on the bank layer 1170 . As shown in the first, second and third embodiments of the present invention, the light emitting part 1180 includes the first light emitting part 110 formed on the first electrode 102 and the second light emitting part 1180. It consists of a part 120 and a third light emitting part 130 .

A second electrode 1104 is formed on the light emitting part 1180 .

Although not shown in FIG. 11 , an encapsulation portion may be formed on the second electrode 104 . The sealing part serves to prevent moisture from penetrating into the light emitting part 1180 . The encapsulation part may be formed of a plurality of layers in which inorganic materials different from each other are stacked, or a plurality of layers in which inorganic materials and organic materials are alternately stacked. And, an encapsulation substrate may be additionally configured on the encapsulation part. The encapsulation substrate may be made of glass, plastic, or metal. The encapsulation substrate may be adhered to the encapsulation unit by an adhesive.

In the above embodiment, the bottom emission method is described as an example. In the case of a bottom emission method, a polarizer must be used to lower the reflectance of an external light source. Due to the use of the polarizing plate, a problem in which luminance is reduced by about 60% may occur.

Therefore, through various experiments, the inventors of the present invention can improve the luminous efficiency and panel efficiency of the light emitting layer, and invent a top emission type white organic light emitting device of a new structure with improved luminance and aperture ratio because a polarizer is not used. did Also, compared to an organic light emitting display device using a bottom emission method, an organic light emitting display device using a top emission method according to an exemplary embodiment of the present invention may have an improved aperture ratio.

12 is a schematic diagram showing white organic light emitting diodes according to the fourth and fifth embodiments of the present invention.

The white organic light emitting device 200 shown in FIG. 12 includes first and second electrodes 202 and 204 and a first light emitting unit 210 and a second light emitting unit 220 between the first and second electrodes 202 and 204. and a third light emitting unit 230 .

The first electrode 202 is an anode supplying holes and may be formed of gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), or an alloy thereof, , but is not necessarily limited thereto. Alternatively, it may be formed of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), etc., which are transparent conductive materials such as TCO (Transparent Conductive Oxide), but is not necessarily limited thereto.

The second electrode 204 is a cathode supplying electrons and may be formed of a transparent conductive material such as TCO (Transparent Conductive Oxide) such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), or the like. may be, but is not necessarily limited thereto. Alternatively, the second electrode 204 may be formed of metallic materials such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), or an alloy thereof, It is not necessarily limited to this. Alternatively, the second electrode 204 may include transparent conductive oxide (TCO), indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), and metallic materials such as gold (Au) and silver (Ag). , aluminum (Al), molybdenum (Mo), may be formed of two layers such as magnesium (Mg), but is not necessarily limited thereto.

The first electrode 202 and the second electrode 204 may be referred to as an anode or a cathode, respectively.

Also, the first electrode 202 may be a reflective electrode, and the second electrode 204 may be a transflective electrode.

The white organic light emitting device 200 of the top emission type of the present invention includes a first light emitting unit 210, a second light emitting unit 220 and A third light emitting unit 230 is included. And, in the white organic light emitting device 200 of the top emission type of the present invention, the position of the second electrode from the first electrode and the position of light emission of the first light emitting layer, the second light emitting layer, and the third light emitting layer are set. This improves luminance, luminous efficiency and panel efficiency. That is, an Emission Position of Emitting Layers (EPEL) structure is applied to the first light emitting layer, the second light emitting layer, and the third light emitting layer. In addition, the first light emitting unit 210, the second light emitting unit 220, and the third light emitting unit 230 have a maximum light emitting range in the light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. It has an EPEL (Emission Position of Emitting Layers) structure with

The position L0 of the second electrode 204 is set to be 4,700 Å to 5,400 Å from the first electrode 202 . Alternatively, the position L0 of the second electrode 204 is set to be 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202 . In addition, the emission peaks of the light emitting layers constituting the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 are positioned at a specific wavelength, and light of the specific wavelength is positioned. By emitting light, the luminous efficiency can be improved. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

The position L0 of the second electrode 204 is set from the first electrode 202, and the light emitting position L1 of the first light emitting part 210 closest to the first electrode 202 ) is set to be between 150 Å and 700 Å. Alternatively, the light emitting position L1 of the first light emitting part 210 is set to be 150 Å to 700 Å from the reflective surface of the first electrode 202 . The first light emitting part 210 may be composed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L1 of the first light emitting part 210 is in the range of 150 Å to 700 Å from the first electrode 202. to be located within Alternatively, the light emitting position L1 of the first light emitting part 210 is located within a range of 150 Å to 700 Å from the reflective surface of the first electrode 202 . Therefore, the emitting peak is located in the blue emitting region and the first light emitting unit 210 emits maximum luminance by emitting light of a wavelength corresponding to the emitting peak. . The peak wavelength of the light emitting region of the blue light emitting layer may be in the range of 440 nm to 480 nm. The auxiliary light emitting layer of the first light emitting unit 210 may be composed of one of a red light emitting layer, a green light emitting layer, and a yellow-green light emitting layer, or a combination thereof. In addition, the peak wavelength of the light emitting region of the light emitting layer constituting the first light emitting part 210 including the auxiliary light emitting layer may be in the range of 440 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L2 of the second light emitting part 220 is set to be 1,600 Å to 2,300 Å from the first electrode 202 . Alternatively, the light emitting position L2 of the second light emitting part 220 is set to be positioned within a range of 1,600 Å to 2,300 Å from the reflective surface of the first electrode 202 .

The second light emitting part 220 may be composed of a yellow-green light emitting layer. Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L2 of the second light emitting part 220 is 1,600 Å to 2,300 Å from the first electrode 202 to be located within the range of Å. Alternatively, the light emitting position L2 of the second light emitting part 220 is located within a range of 1,600 Å to 2,300 Å from the reflective surface of the first electrode 202 .

Therefore, the second light emitting unit 220 achieves maximum luminance by emitting light having a wavelength corresponding to the emitting peak and positioning the emitting peak in the yellow-green emitting region. make it possible to pay The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

Also, depending on the characteristics or structure of the device, the second light emitting unit 220 may be composed of two layers, a red light emitting layer and a green light emitting layer. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved. Therefore, the peak wavelength of the light emitting region of the red light emitting layer and the green light emitting layer may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

In addition, depending on the characteristics or structure of the device, the second light emitting unit 220 may be composed of two layers of a red light emitting layer and a yellow-green light emitting layer. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In addition, peak wavelengths of the emission regions of the red emission layer and the yellow-green emission layer may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

In addition, depending on the characteristics or structure of the device, the second light emitting unit 220 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In addition, the peak wavelength of the light emitting region of the yellow light emitting layer and the red light emitting layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light-emitting part 220 is a yellow-green light-emitting layer, or a yellow light-emitting layer and a red light-emitting layer, or a red light-emitting layer and a green light-emitting layer, or a yellow-green ( When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting part 220 is in the range of 510 nm to 650 nm. can do. Here, the peak wavelength may be a light emitting region.

The light emitting position L3 of the third light emitting part 230 is set to be positioned within a range of 2,400 Å to 3,100 Å from the first electrode 202 . Alternatively, the light emitting position L3 of the third light emitting part 230 is set to be positioned within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 202 .

The third light emitting part 230 may be composed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L3 of the third light emitting part 230 is 2,400 Å to 3,100 Å from the first electrode 202. to be located within the range of Å. Alternatively, the light emitting position L3 of the third light emitting part 230 is set to be positioned within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 202 .

Therefore, the emitting peak of the third light emitting part 230 is located in the blue light emitting region so that the third light emitting part 230 can emit maximum luminance. The peak wavelength of the light emitting region of the blue light emitting layer may be in the range of 440 nm to 480 nm. As an auxiliary light emitting layer, the third light emitting part 230 may include one or a combination of a red light emitting layer, a green light emitting layer, and a yellow-green light emitting layer. In addition, the peak wavelength of the light emitting region of the light emitting layer constituting the third light emitting part 230 including the auxiliary light emitting layer may be in the range of 440 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The present invention applies a top emission (Emission Position of Emitting Layers) structure in which the emission position of the light emitting layers is set regardless of the thickness of at least one light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers. Emission method relates to a white organic light emitting device. And, regardless of the thickness of at least one light-emitting layer, the number of light-emitting layers, the thickness of organic layers, and the number of organic layers, the first light-emitting part 210, the second light-emitting part 220, and the third light-emitting part The unit 230 has an Emission Position of Emitting Layers (EPEL) structure having a maximum emission range in emission regions of the first emission layer, the second emission layer, and the third emission layer.

13 is a schematic diagram showing a white organic light emitting device according to a fourth embodiment of the present invention.

The white organic light emitting device 200 shown in FIG. 13 includes a first light emitting unit 210 between the first electrode 202 and the second electrode 204 and the first and second electrodes 202 and 204, and the second light emitting unit 210 . A part 220 and a third light emitting part 230 are provided.

The first electrode 202 and the second electrode 204 may be referred to as an anode or a cathode, respectively.

Also, the first electrode 202 may be a reflective electrode, and the second electrode 204 may be a transflective electrode.

Referring to FIG. 13 , the position of the second electrode 204 is set within a range of 4,700 Å to 5,400 Å from the first electrode 202 . By setting the position (L0) of the first electrode 202, emission peaks of the light emitting layers constituting the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength.

The first light emitting part 210 includes a first hole transport layer (HTL) 212, a first light emitting layer (EML) 214, and a first electron transport layer (ETL) 216 on the first electrode 202. It can be done by

An auxiliary electrode 203 may be formed on the first electrode 202 . The auxiliary electrode 203 is composed of ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), etc., which are transparent conductive materials such as metal oxide or TCO (Transparent Conductive Oxide). and is not necessarily limited thereto.

Although not shown in the drawings, the first light emitting part 210 may additionally include a hole injection layer (HIL). The hole injection layer HIL is positioned on the auxiliary electrode 203 and serves to smoothly inject holes from the first electrode 202 . The first hole transport layer (HTL) 212 supplies holes from the hole injection layer (HIL) to the first light emitting layer (EML) 214 . The first electron transport layer (ETL) 216 supplies electrons from the first charge generating layer (CGL) 240 to the first light emitting layer (EML) 214 .

In the first light emitting layer (EML) 214, holes supplied through the first hole transport layer (HIL) 212 and electrons supplied through the first electron transport layer (ETL) 216 As they recombine, light is produced.

When the first hole transport layer (HTL) 212 is formed on the first electrode 202 without forming the auxiliary electrode 203, electrons are transferred to the first light emitting layer (EML) 214. The movement becomes difficult, and the movement of holes into the first light emitting layer (EML) 214 becomes difficult, causing a problem in that the driving voltage increases. Depending on the characteristics or structure of the device, the auxiliary electrode 203 may not be configured.

The first hole transport layer (HTL) 212 may be formed by applying two or more layers or two or more materials.

The first electron transport layer (ETL) 216 may be formed by applying two or more layers or two or more materials.

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 214 . The hole blocking layer (HBL) prevents holes generated in the first light emitting layer (EML) 214 from passing over to the first electron transport layer (ETL) 216, so that the first light emitting layer (EML) 214 The luminous efficiency of the first light emitting layer (EML) 214 may be improved by improving the coupling of electrons and holes in the . The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the first light emitting layer (EML) 214 . The electron blocking layer (EBL) prevents electrons generated in the first light emitting layer (EML) 214 from passing over to the first hole transport layer (HTL) 212, thereby preventing the first light emitting layer (EML) 214 The luminous efficiency of the first light emitting layer (EML) 214 may be improved by improving the coupling of electrons and holes in the . The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 214 is composed of a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When configuring the first light emitting layer (EML) 214 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) 214 . ) It is also possible to configure above or below 214. In addition, the auxiliary light-emitting layer, the yellow-green light-emitting layer, the red light-emitting layer, or the green light-emitting layer, is identically or differently configured above and below the first light-emitting layer (EML) 214. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 214, the peak wavelength of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 212, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 202 and the first light emitting layer (EML) 214 and the auxiliary electrode 203 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 202 and the first light emitting layer (EML) 214 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 212, regardless of the number or thickness of the auxiliary electrodes 203, regardless of the number or thickness of the electron blocking layer (EBL), or the hole injection layer Regardless of the number or thickness of the first light-emitting layer (HIL), regardless of the number or thickness of all organic layers between the first electrode 202 and the first light-emitting layer (EML) 214, the first light-emitting layer (EML) 214 The light emitting position L1 of is set to be positioned within a range of 150 Å to 700 Å from the first electrode 202 . Alternatively, the light emitting position L1 of the first light emitting layer (EML) 214 is set to be located within a range of 150 Å to 700 Å from the reflective surface of the first electrode 202 . Therefore, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the position L1 of the first light emitting layer (EML) 214 from the first electrode 202 is in the range of 150 Å to 700 Å. It can be set to be located within Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 214 is 150 Å away from the reflective surface of the first electrode 202. to 700 Å.

The second light emitting part 220 may include a second hole transport layer (HTL) 222 , a second light emitting layer (EML) 224 , and a second electron transport layer (ETL) 226 .

The second hole transport layer (HTL) 222 may be formed by applying two or more layers or two or more materials.

The second hole transport layer (HTL) 222 may be made of the same material as the first hole transport layer (HTL) 212, but is not necessarily limited thereto.

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 222 . The hole injection layer (HIL) serves to inject holes from the first charge transport layer (CGL) 240 into the second hole transport layer (HTL) 222 .

The second electron transport layer (ETL) 226 may be formed by applying two or more layers or two or more materials.

The second electron transport layer (ETL) 226 may be made of the same material as the first electron transport layer (ETL) 216, but is not necessarily limited thereto.

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 224 . The hole blocking layer (HBL) prevents holes generated in the second light emitting layer (EML) 224 from passing over to the second electron transport layer (ETL) 226, thereby forming the second light emitting layer (EML) 224 The luminous efficiency of the second light emitting layer (EML) 224 may be improved by improving the coupling of electrons and holes in . The second electron transport layer (ETL) 226 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 224 . The electron blocking layer (EBL) prevents electrons generated in the second light emitting layer (EML) 224 from passing over to the second hole transport layer (HTL) 222, thereby preventing the second light emitting layer (EML) 224 The luminous efficiency of the second light emitting layer (EML) 224 may be improved by improving the coupling of electrons and holes in . The second hole transport layer (HTL) 222 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 224 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 224 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (224). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 224 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the second emission layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 240 may be further formed between the first light emitting part 210 and the second light emitting part 220 . The first charge generating layer (CGL) 240 controls the charge balance between the first light emitting part 210 and the second light emitting part 220 . The first charge generating layer (CGL) 240 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first charge generating layer (CGL) 240 may be formed of a single layer.

The first light emitting layer (EML) 214, the first electron transport layer (ETL) 216, the first charge generation layer (CGL) 240, the second hole transport layer 222, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 and the first light emitting layer (EML) 214 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 216, or the second

Regardless of the number or thickness of the hole transport layers (HTL) 222, regardless of the number or thickness of the first charge generation layer (CGL) 240, or regardless of the number or thickness of the hole blocking layer (HBL), or Regardless of the number or thickness of electron blocking layers (EBL), regardless of the number or thickness of hole injection layers (HIL), regardless of the number or thickness of the first light emitting layer (EML) 214, or the first electrode 202 and the first light emitting layer (EML) 214 regardless of the number or thickness of all organic layers, or between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 Regardless of the number or thickness of all the organic layers present, the light emitting position L2 of the second light emitting layer (EML) 224 is set to be located within a range of 1,600 Å to 2,300 Å from the first electrode 202 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 224 is set to be located within a range of 1,600 Å to 2,300 Å from the reflective surface of the first electrode 202 . Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L2 of the second light emitting layer (EML) 224 from the first electrode 202 may be set to be positioned within a range of 1,600 Å to 2,300 Å. Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L2 of the second light emitting layer (EML) 224 from the reflective surface of the first electrode 202 may be set to be positioned within a range of 1,600 Å to 2,300 Å.

The third light emitting part 230 may include a third electron transport layer (ETL) 236 , a third light emitting layer (EML) 234 , and a third hole transport layer (HTL) 232 . Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 236 . The electron injection layer (EIL) serves to inject electrons from the second electrode 204 into the third electron transport layer (ETL) 236 .

The third hole transport layer (HTL) 232 is TPD (N, N'-bis (3-methylphenyl) -N, N'-bis (phenyl) -benzidine) or NPB (N, N'-di (naphthalen- 1-yl) -N, N'-diphenyl-benzidine), etc., but is not necessarily limited thereto.

The third hole transport layer (HTL) 232 may be configured by applying two or more layers or two or more materials.

The third hole transport layer (HTL) 232 may be made of the same material as the second hole transport layer (HTL) 222, but is not necessarily limited thereto.

A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 232 . The hole injection layer (HIL) serves to inject holes from the second charge generation layer (CGL) 250 into the third hole transport layer (HTL) 232 .

The third electron transport layer (ETL) 236 may be made of oxadiazole, triazole, phenanthroline, benzoxazole, or benzthiazole. It is not necessarily limited to this.

The third electron transport layer (ETL) 236 may be configured by applying two or more layers or two or more materials.

The third electron transport layer (ETL) 236 may be made of the same material as the second electron transport layer (ETL) 226, but is not necessarily limited thereto.

A second charge generating layer (CGL) 250 may be further formed between the second light emitting part 220 and the third light emitting part 230 . The second charge generating layer (CGL) 250 adjusts the charge balance between the second light emitting part 220 and the third light emitting part 230 . The second charge generating layer (CGL) 250 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The N-type charge generating layer (N-CGL) serves to inject electrons into the second light emitting part 220, and the P-type charge generating layer (P-CGL) serves to inject electrons into the third light emitting part 230. It serves to inject holes.

The N-type charge generation layer (N-CGL) is an alkali metal such as lithium (Li), sodium (Na), potassium (K), or cesium (Cs), or magnesium (Mg), strontium (Sr), barium ( Ba), or an organic layer doped with an alkaline earth metal such as radium (Ra), but is not necessarily limited thereto.

The P-type charge generating layer (P-CGL) may be formed of an organic layer including a P-type dopant, but is not necessarily limited thereto.

The second charge generating layer (CGL) 250 is made of the same material as the N-type charge generating layer (N-CGL) of the first charge generating layer (CGL) 240 and the P-type charge generating layer (P-CGL). It may consist of, but is not necessarily limited thereto.

The second charge generating layer (CGL) 250 may be formed of a single layer.

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 234 . The hole blocking layer (HBL) prevents holes generated in the third light emitting layer (EML) 234 from passing over to the third electron transport layer (ETL) 236, thereby forming the third light emitting layer (EML) 234 The light emitting efficiency of the third light emitting layer (EML) 234 may be improved by improving the coupling of electrons and holes in . The third electron transport layer (ETL) 236 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 234 . The electron blocking layer (EBL) prevents electrons generated in the third light emitting layer (EML) 234 from passing over to the third hole transport layer (HTL) 232, thereby preventing the third light emitting layer (EML) 234 The light emitting efficiency of the third light emitting layer (EML) 234 may be improved by improving the coupling of electrons and holes in . The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 234 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 134 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 234) is also possible. In addition, the auxiliary light-emitting layer, the yellow-green or red light-emitting layer or the green light-emitting layer, may be configured identically or differently above and below the third light-emitting layer (EML) 234. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 234, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 224, the second electron transport layer (ETL) 226, the second charge generation layer (CGL) 250, the third hole transport layer 232, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL) and the like can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 and the second light emitting layer (EML) 224 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 may be referred to as a third organic layer.

Regardless of the number or thickness of the second electron transport layer (ETL) 226, regardless of the number or thickness of the second charge generation layer (CGL) 250, or the third hole transport layer (HTL) 232 Regardless of the number or thickness of the second light emitting layer (EML) 224, regardless of the number or thickness of the second light emitting layer (EML) 224, regardless of the number or thickness of the first light emitting layer (EML) 214, or the first electrode 202 ) and the first light emitting layer (EML) 214, regardless of the number or thickness of all organic layers, or all the organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224. Regardless of the number or thickness of organic layers or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234, the third light emitting layer (EML) ( 234) is set to be positioned within a range of 2,400 Å to 3,100 Å from the first electrode 202. Alternatively, the light emitting position L3 of the third light emitting layer (EML) 234 is set to be positioned within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 202 . Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Position (L3) of the third light emitting layer (EML) 234 from the first electrode 202 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer may be set to be located within the range of 2,400 Å to 3,100 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first The position of the third light emitting layer (EML) 234 from the reflective surface of the first electrode 202 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer. (L3) may be set to be positioned within a range of 2,400 Å to 3,100 Å.

In addition, all layers such as the third light emitting layer (EML) 234, the third electron transport layer (ETL) 236, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 234 and the second electrode 204, the second electrode 204, and the third light emitting layer (EML) 234 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 234 and the second electrode 204 and including the second electrode 204 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 236, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the second Regardless of the number or thickness of the electrodes 204, regardless of the number or thickness of the third light emitting layer (EML) 234, or all between the substrate 201 and the first light emitting layer (EML) 214 Regardless of the number or thickness of organic layers, or regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224, or the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 regardless of the number or thickness of all organic layers, or all organic layers between the third light emitting layer (EML) 2134 and the second electrode 204 Regardless of the thickness, the position L0 of the second electrode 204 from the first electrode 202 may be set to be located within a range of 4,700 Å to 5,400 Å. Alternatively, the position L0 of the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202 .

Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 204 may be set to be located within a range of 4,700 Å to 5,400 Å from the first electrode 202 regardless of the thickness of . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202 regardless of the thickness of the .

The structure shown in FIG. 13 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

14 is a diagram showing a light emitting position of an organic light emitting device according to a fourth embodiment of the present invention.

In FIG. 14, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 202, which can be referred to as a contour map. Here, except for the first electrode 202 and the second electrode 204, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the first light emitting layer (EML) 214 constituting the first light emitting part 210 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 214 is set in the range of 150 Å to 700 Å so that the emission peak 214E is located at 440 nm to 480 nm. Due to this, maximum efficiency can be obtained by emitting light from the first light emitting layer (EML) 214 in the range of 440 nm to 480 nm.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the first light emitting layer (EML) 214 constituting the first light emitting part 210. In this case, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 214 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 14 , the first light emitting layer (EML) 214 does not include an auxiliary light emitting layer, and the first light emitting layer (EML) 214 takes a blue light emitting layer as an example to show the light emitting position. Accordingly, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may produce maximum efficiency in the range of 440 nm to 480 nm.

Since the second light emitting layer (EML) 224 constituting the second light emitting part 220 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 ( peak wavelength range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 224 to be positioned within the range of 1,600 Å to 2,300 Å, the emission peak 224E of the second light emitting layer (EML) 224 is 510 nm. to 580 nm. Due to this, maximum efficiency can be obtained by emitting light in the range of 510 nm to 580 nm from the second light emitting layer (EML) 224 .

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light between 510 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the second light emitting layer (EML) 224, to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 224, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 224 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the second light emitting layer (EML) 224 is emitted in the range of 510 nm to 650 nm.

In FIG. 14 , an auxiliary light emitting layer is not included in the second light emitting layer (EML) 224, and a yellow-green light emitting layer of the second light emitting layer (EML) 224 is taken as an example, and the light emitting position is shown. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may have maximum efficiency in the range of 510 nm to 580 nm.

Since the third light emitting layer (EML) 234 constituting the third light emitting part 230 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 234 to be located within the range of 2,400 Å to 3,100 Å, the emission peak 234E of the third light emitting layer (EML) 234 is 440 nm. to 480 nm. For this reason, the third light emitting layer (EML) 234 emits light in the range of 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 234 constituting the third light emitting part 230. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 234 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 14 , an auxiliary light emitting layer is not included in the third light emitting layer (EML) 234, and the third light emitting layer (EML) 234 is a blue light emitting layer, and the light emitting position is shown as an example. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may have maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. Therefore, the present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

In addition, a light emitting range in which the light emitting layers can achieve maximum efficiency at the specific wavelength may be referred to as a maximum light emitting range. Accordingly, the maximum emission range of the first emission layer may be 440 nm to 470 nm, the maximum emission range of the second emission layer may be 530 nm to 570 nm, and the maximum emission range of the third emission layer may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

15 is a diagram showing an EL spectrum according to a fourth embodiment of the present invention.

In FIG. 15, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 15, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 700 Å from the first electrode 202, the minimum position is set to 150 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 700 Å from the first electrode 202, the maximum position is set to 700 Å.

Example (optimal position) is the part set as the light emitting position of the fourth embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 700 Å from the first electrode 202, the light emitting position in the embodiment is set to the range of 150 Å to 700 Å. .

As shown in FIG. 15, when the minimum light emitting position is out of position in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 7 below. When the efficiency of the comparative example is 100%, the efficiency of the fourth embodiment of the present invention is shown.

In Table 7 below, the comparative example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The yellow-green light emitting layer and the third light emitting part are composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

*As shown in Table 7, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, if the efficiency of the comparative example is 100%, the red efficiency is increased by about 39% , it can be seen that the green efficiency increased by about 63%. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 53%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 8 below.

Table 8 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimal position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 8, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the example (minimum position) and the example (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the fourth embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

A light emitting position of the first light emitting layer may be set in a range of 150 Å to 700 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,600 Å to 2,300 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,400 Å to 3,100 Å from the first electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

16 is a schematic diagram showing a white organic light emitting device according to a fifth embodiment of the present invention. In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted.

The white organic light emitting device 200 shown in FIG. 16 includes a first light emitting unit 210 between the first electrode 202 and the second electrode 204 and the first and second electrodes 202 and 204, and the second light emitting unit 210 . A part 220 and a third light emitting part 230 are provided.

The position of the second electrode 204 is set to be located at 4,700 Å to 5,400 Å from the first electrode 202 . By setting the position (L0) of the first electrode 202, emission peaks of the light emitting layers constituting the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength.

The first light emitting part 210 includes a first hole transport layer (HTL) 212, a first light emitting layer (EML) 214, and a first electron transport layer (ETL) 216 on the first electrode 202. can be done by

An auxiliary electrode 203 may be formed on the first electrode 202 . In addition, the auxiliary electrode 203 may not be configured depending on the characteristics or structure of the device.

Although not shown in the drawing, the first light emitting part 210 may additionally include a hole injection layer (HIL) on the auxiliary electrode 203 . A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 214 . The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the first light emitting layer (EML) 214 . The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 214 is composed of a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When configuring the first light emitting layer (EML) 214 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) 214 . ) It is also possible to configure above or below 214. In addition, the auxiliary light-emitting layer, the yellow-green light-emitting layer, the red light-emitting layer, or the green light-emitting layer, is identically or differently configured above and below the first light-emitting layer (EML) 214. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 214, the peak wavelength of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 212, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 202 and the first light emitting layer (EML) 214 and the auxiliary electrode 203 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 202 and the first light emitting layer (EML) 214 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 212, regardless of the number or thickness of the auxiliary electrodes 203, or regardless of the number or thickness of the electron blocking layer (EBL), or hole injection Regardless of the number or thickness of layers HIL, regardless of the number or thickness of all organic layers between the first electrode 202 and the first light emitting layer (EML) 214, the first light emitting layer (EML) 214 ) is set to be located within a range of 150 Å to 650 Å from the first electrode 202 . Alternatively, the light emitting position L1 of the first light emitting layer (EML) 214 is set to be located within a range of 150 Å to 650 Å from the reflective surface of the first electrode 202 . Therefore, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the position L1 of the first light emitting layer (EML) 214 from the first electrode 202 is in the range of 150 Å to 650 Å. It can be set to be located within Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 214 is 150 Å away from the reflective surface of the first electrode 202. to 650 Å.

The second light emitting part 220 may include a second hole transport layer (HTL) 222 , a second light emitting layer (EML) 224 , and a second electron transport layer (ETL) 226 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 222 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 224 . The second electron transport layer (ETL) 226 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 224 . The second hole transport layer (HTL) 222 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 224 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

And, the second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (224). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 224 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the second emission layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 240 may be further formed between the first light emitting part 210 and the second light emitting part 220 . The first charge generating layer (CGL) 240 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 214, the first electron transport layer (ETL) 216, the first charge generation layer (CGL) 240, the second hole transport layer 222, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 and the first light emitting layer (EML) 214 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 216, regardless of the number or thickness of the second hole transport layer (HTL) 222, or the first charge generation layer (CGL) 240 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the first light emitting layer (EML) 214, or regardless of the number or thickness of all organic layers between the first electrode 202 and the first light emitting layer (EML) 214, or the Regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224, the light emitting position L2 of the second light emitting layer (EML) 224 is It is set to be positioned within the range of 1,700 Å to 2,300 Å from the first electrode 202 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 224 is set to be located within a range of 1,700 Å to 2,300 Å from the reflective surface of the first electrode 202 . Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L1 of the second light emitting layer (EML) 224 from the first electrode 202 may be set to be positioned within a range of 1,700 Å to 2,300 Å. Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L1 of the second light emitting layer (EML) 224 from the reflective surface of the first electrode 202 may be set to be positioned within a range of 1,700 Å to 2,300 Å.

The third light emitting part 230 may include a third electron transport layer (ETL) 236 , a third light emitting layer (EML) 234 , and a third hole transport layer (HTL) 232 . Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 236 . A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 232 . A second charge generating layer (CGL) 250 may be further formed between the second light emitting part 220 and the third light emitting part 230. The second charge generating layer (CGL) 250 includes An N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL) may be included.

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 234 . The third electron transport layer (ETL) 236 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 234 . The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 234 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 234 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 234) is also possible. In addition, the auxiliary light-emitting layer, the yellow-green or red light-emitting layer or the green light-emitting layer, may be configured identically or differently above and below the third light-emitting layer (EML) 234. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 234, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 224, the second electron transport layer (ETL) 226, the second charge generation layer (CGL) 250, the third hole transport layer 232, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL) and the like can be referred to as organic layers. All layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 may be referred to as a third organic layer.

Regardless of the number or thickness of the second electron transport layer (ETL) 226, regardless of the number or thickness of the second charge generation layer (CGL) 250, or the third hole transport layer (HTL) 232 Regardless of the number or thickness of the second light emitting layer (EML) 224, regardless of the number or thickness of the second light emitting layer (EML) 224, regardless of the number or thickness of the first light emitting layer (EML) 214, or the first electrode 202 ) and the first light emitting layer (EML) 214, regardless of the number or thickness of all organic layers, or all the organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224. Regardless of the number or thickness of organic layers or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234, the third light emitting layer (EML) ( 234) is set to be positioned within a range of 2,400 Å to 3,000 Å from the first electrode 202. Alternatively, the light emitting position L3 of the third light emitting layer (EML) 234 is set to be positioned within a range of 2,400 Å to 3,000 Å from the reflective surface of the first electrode 202 . Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Position (L3) of the third light emitting layer (EML) 234 from the first electrode 202 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer may be set to be positioned within a range of 2,400 Å to 3,000 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first The position of the third light emitting layer (EML) 234 from the reflective surface of the first electrode 202 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer. (L3) may be set to be positioned within a range of 2,400 Å to 3,000 Å.

In addition, all layers such as the third light emitting layer (EML) 234, the third electron transport layer (ETL) 236, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 234 and the second electrode 204 and the second electrode 204 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 234 and the second electrode 204 and including the second electrode 204 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 236, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the second Regardless of the number or thickness of the electrodes 204, regardless of the number or thickness of the first light emitting layer (EML) 214, regardless of the number or thickness of the second light emitting layer (EML) 224, or regardless of the number or thickness of the second light emitting layer (EML) 224, or 3 regardless of the number or thickness of the light emitting layer (EML) 234, regardless of the number or thickness of all organic layers between the substrate 201 and the first light emitting layer (EML) 214, or the first light emitting layer ( EML) 214 and the second light emitting layer (EML) 224, regardless of the number or thickness of all organic layers, or the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234 from the first electrode 202 regardless of the number or thickness of all organic layers in between or regardless of the thickness of all organic layers between the third light emitting layer (EML) 234 and the second electrode 204. The position L0 of the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å. Alternatively, the position L0 of the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202 . Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 204 may be set to be located within a range of 4,700 Å to 5,400 Å from the first electrode 202 regardless of the thickness of . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202 regardless of the thickness of the .

The structure shown in FIG. 16 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

17 is a diagram showing a light emitting position of an organic light emitting device according to a fifth embodiment of the present invention.

In FIG. 17, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 202, which can be referred to as a contour map. Here, except for the first electrode 202 and the second electrode 204, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the first light emitting layer (EML) 214 constituting the first light emitting part 210 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 214 is set in the range of 150 Å to 650 Å so that the emission peak 214E is located at 440 nm to 480 nm. Due to this, maximum efficiency can be obtained by emitting light from the first light emitting layer (EML) 214 in the range of 440 nm to 480 nm.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the first light emitting layer (EML) 214 constituting the first light emitting part 210. In this case, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 214 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 17 , the first light emitting layer (EML) 214 does not include an auxiliary light emitting layer, and the light emitting position of the first light emitting layer (EML) 214 is a blue light emitting layer as an example. Accordingly, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may produce maximum efficiency in the range of 440 nm to 480 nm.

Since the second light emitting layer (EML) 224 constituting the second light emitting part 220 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 ( peak wavelength range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 224 in the range of 1,700 Å to 2,300 Å, the emission peak 224E of the second light emitting layer (EML) 224 is 510 nm to 580 nm. positioned at nm. Due to this, maximum efficiency can be obtained by emitting light in the range of 510 nm to 580 nm from the second light emitting layer (EML) 224 .

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the second light emitting layer (EML) 224, to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 224, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 224 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the second light emitting layer (EML) 224 is emitted in the range of 510 nm to 650 nm.

In FIG. 17 , an auxiliary light emitting layer is not included in the second light emitting layer (EML) 224, and a yellow-green light emitting layer of the second light emitting layer (EML) 224 is taken as an example, and the light emitting position is shown. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may have maximum efficiency in the range of 510 nm to 580 nm.

Since the third light emitting layer (EML) 234 constituting the third light emitting part 230 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 234 in the range of 2,400 Å to 3,000 Å, the emission peak 234E of the third light emitting layer (EML) 234 is 440 nm to 480 nm. positioned at nm. For this reason, the third light emitting layer (EML) 234 emits light in the range of 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 234 constituting the third light emitting part 230. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 234 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 17 , the third light emitting layer (EML) 234 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 234 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may have maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 440 nm to 470 nm, the maximum emission range of the second emission layer is 530 nm to 570 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

18 is a diagram showing an EL spectrum according to a fifth embodiment of the present invention.

* In FIG. 18, the horizontal axis represents the wavelength region of light, and the vertical axis represents the luminous intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 18, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 650 Å from the first electrode 202, the minimum position is set to 150 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 650 Å from the first electrode 102, the maximum position is set to 650 Å.

Example (optimum position) is the part set as the light emitting position of the fifth embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 214 is in the range of 150 Å to 650 Å from the second electrode 202, the light emitting position in the embodiment is set in the range of 150 Å to 650 Å. .

As shown in FIG. 18, when the minimum light emitting position is out of position in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 9 below. When the efficiency of the comparative example is 100%, the efficiency of the fifth embodiment of the present invention is shown.

In Table 9 below, Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part has a blue light emitting layer and the second light emitting part The yellow-green light emitting layer and the third light emitting part are composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 9, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, if the efficiency of the comparative example is 100%, the red efficiency is increased by about 39%, It can be seen that the green efficiency increased by about 63%. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 61%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 10 below.

Table 10 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 10, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the example (minimum position) and the example (maximum position). . And, comparing Table 8 of the fourth embodiment of the present invention with Table 10 of the fifth embodiment of the present invention, at the boundary between the embodiment (minimum position) and the embodiment (maximum position), green and blue ) and white efficiency were further improved. Therefore, according to the fifth exemplary embodiment of the present invention, an organic light emitting display device with further improved efficiency can be provided. In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the fifth embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

The light emitting position of the first light emitting layer may be set within a range of 150 Å to 650 Å from the first electrode.

The light emitting position of the second light emitting layer may be set within a range of 1,700 Å to 2,300 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,400 Å to 3,000 Å from the first electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

19 is a schematic diagram showing a white organic light emitting diode according to a sixth embodiment of the present invention. In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted. In this embodiment, the light emitting position of the light emitting layers is set from the second electrode, and the light emitting position can be set from the second electrode according to device design.

The white organic light emitting device 200 shown in FIG. 19 includes a first light emitting unit 210 between the first electrode 202 and the second electrode 204 and the first and second electrodes 202 and 204, and the second light emitting unit 210 . A part 220 and a third light emitting part 230 are provided.

The first electrode 202 is positioned within a range of 4,700 Å to 5,400 Å from the second electrode 204 . By setting the position (L0) of the first electrode 202, emission peaks of the light emitting layers constituting the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength.

The third light emitting part 230 includes a third electron transport layer (ETL) 236, a third light emitting layer (EML) 234, and a third hole transport layer (HTL) 232 under the second electrode 204. can be made including Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 236 . A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 232 . A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 234 . The third electron transport layer (ETL) 236 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 234 . The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 234 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 234 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 234) is also possible. In addition, the auxiliary light-emitting layer, the yellow-green or red light-emitting layer or the green light-emitting layer, may be configured identically or differently above and below the third light-emitting layer (EML) 234. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 234, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the third electron transport layer (ETL) 236, the third light emitting layer (EML) 234, the electron injection layer (EIL), and the hole blocking layer (HBL) may be referred to as organic layers. All organic layers positioned between the second electrode 204 and the third light emitting layer (EML) 234 and the second electrode 204 and the third light emitting layer (EML) 234 may be referred to as organic layers. . Accordingly, all organic layers positioned between the second electrode 204 and the third light emitting layer (EML) 234 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 236, regardless of the number or thickness of the third light emitting layer (EML) 234, or regardless of the number or thickness of the electron injection layer (EIL), Alternatively, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of the second electrodes 204, or between the second electrode 204 and the third light emitting layer (EML) 234 Regardless of the number or thickness of all organic layers present, the light emitting position L3 of the third light emitting layer (EML) 234 is set to be located within a range of 2,050 Å to 2,750 Å from the second electrode 204. Within the range Regardless of the number of at least one of the fourth organic layers, the thickness of the fourth organic layer, the number of the third light emitting layers, and the thickness of the third light emitting layer, the third light emitting layer ( EML) 234 is set to be located within the range of 2,050 Å to 2,750 Å.

The second light emitting part 220 may include a second hole transport layer (HTL) 222 , a second light emitting layer (EML) 224 , and a second electron transport layer (ETL) 226 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 222 . A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 224 . The second electron transport layer (ETL) 226 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 224 . The second hole transport layer (HTL) 222 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 224 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

And, the second light emitting layer (EML) 224 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer.

And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( It is also possible to configure above or below the EML) (224). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the second light emitting layer ( EML) above and below the 224 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the second emission layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the second emission layer (EML) 224 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 124 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 250 may be further formed between the second light emitting part 220 and the third light emitting part 230 . The second charge generating layer (CGL) 250 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The second light emitting layer (EML) 224, the second electron transport layer (ETL) 226, the second charge generation layer (CGL) 250, the third hole transport layer (HTL) 232, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 234 and the second light emitting layer (EML) 224 and the second light emitting layer (EML) 224 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 234 and the second light emitting layer (EML) 224 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layer (HTL) 232, regardless of the number or thickness of the second electron transport layer (ETL) 226, or the second charge generation layer (CGL) 250 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the third light emitting layer (EML) 234, regardless of the number or thickness of the second light emitting layer (EML) 224, or the second electrode 204 and the third light emitting layer (EML) ) 234, regardless of the number or thickness of all organic layers, or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 224 and the third light emitting layer (EML) 234, The light emitting position L2 of the second light emitting layer (EML) 224 is set to be positioned within a range of 2,850 Å to 3,550 Å from the second electrode 204 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the position L2 of the second light emitting layer (EML) 224 from the second electrode 204 may be set to be located within a range of 2,850 Å to 3,550 Å. .

The first light emitting part 210 includes a first hole transport layer (HTL) 212, a first light emitting layer (EML) 214, and a first electron transport layer (ETL) 216 on the first electrode 202. It can be done by An auxiliary electrode 203 may be formed on the first electrode 202 . However, depending on the characteristics or structure of the device, the auxiliary electrode 203 may not be configured.

Although not shown in the drawings, the first light emitting part 210 may further include a hole injection layer (HIL) under the first hole transport layer (HTL) 212 . A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 214 . The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the first light emitting layer (EML) 214 . The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 214 is composed of a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When configuring the first light emitting layer (EML) 214 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) 214 . ) It is also possible to configure above or below 214. In addition, the auxiliary light-emitting layer, the yellow-green light-emitting layer, the red light-emitting layer, or the green light-emitting layer, is identically or differently configured above and below the first light-emitting layer (EML) 214. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the first light emitting layer (EML) 214, the peak wavelength of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 240 may be further formed between the first light emitting part 210 and the second light emitting part 220 . The first charge generating layer (CGL) 240 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 214, the first electron transport layer (ETL) 216, the first charge generation layer (CGL) 240, the second hole transport layer 222, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL) and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 and the first light emitting layer (EML) 214 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 216, regardless of the number or thickness of the first charge generation layer (CGL) 240, or the second hole transport layer (HTL) 222 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the third light emitting layer (EML) 234, regardless of the number or thickness of the second light emitting layer (EML) 224, or the number or thickness of the first light emitting layer (EML) 214 Regardless of the number or thickness of all organic layers between the second electrode 204 and the third light emitting layer (EML) 234, or the second light emitting layer (EML) 224 and the third light emitting layer Regardless of the number or thickness of all organic layers between (EML) 234, or regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 , the light emitting position L1 of the first light emitting layer (EML) 214 is set to be located within a range of 4,450 Å to 5,000 Å from the second electrode 204 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the second electrode 204 The position L1 of the first light emitting layer (EML) 214 may be set to be positioned within a range of 4,450 Å to 5,000 Å.

In addition, all layers such as the auxiliary electrode 203, the first hole transport layer (HTL) 212, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 202 and the first light emitting layer (EML) 214 and the first light emitting layer (EML) 214 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 202 and the first light emitting layer (EML) 214 may be referred to as a first organic layer.

Regardless of the number or thickness of the auxiliary electrodes 203, regardless of the number or thickness of the first hole transport layer (HTL) 212, regardless of the number or thickness of the electron blocking layer (EBL), or the hole injection layer Regardless of the number or thickness of the HIL, regardless of the number or thickness of the third light emitting layer (EML) 234, regardless of the number or thickness of the second light emitting layer (EML) 224, or the first Regardless of the number or thickness of the light emitting layers (EML) 214, or regardless of the number or thickness of all organic layers between the second electrode 204 and the third light emitting layer (EML) 234, or the second light emitting layer Regardless of the number or thickness of all organic layers between the (EML) 224 and the third light emitting layer (EML) 234, or between the first light emitting layer (EML) 214 and the second light emitting layer (EML) 224 ) regardless of the number or thickness of all organic layers between the first electrode 202 and regardless of the number or thickness of all organic layers between the first electrode 202 and the first light emitting layer (EML) 214, the first electrode 202 ) may be set to be positioned within a range of 4,700 Å to 5,400 Å from the second electrode 204 .

Thus, thus, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, the The number of first organic layers, the thickness of the first organic layer, the number of the third light-emitting layers, the thickness of the third light-emitting layer, the number of the second light-emitting layers, the thickness of the second light-emitting layer, the number of the first light-emitting layers, the number of the first light-emitting layers, Regardless of the thickness of one light emitting layer, the position L0 of the first electrode 202 from the second electrode 204 may be set to be positioned within a range of 4,700 Å to 5,400 Å.

Here, the light emitting position L1 of the first light emitting layer (EML) 214 may be set to be positioned within a range of 4,450 Å to 5,000 Å from the second electrode 204 . Also, the position L0 of the first electrode 202 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the second electrode 204 . When the light emitting position L1 of the first light emitting layer (EML) 214 is set to 5,000 Å from the second electrode 204, the position L0 of the first electrode 202 is the second electrode ( 204) may be set to be positioned within a range of 5,050 Å to 5,400 Å.

Accordingly, the present invention provides at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, The number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, Regardless of the thickness of the third light emitting layer, the position of the first electrode 202 and the light emitting layers can be set from the second electrode 204 .

The structure shown in FIG. 19 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

20 is a diagram showing a light emitting position of an organic light emitting device according to a sixth embodiment of the present invention.

In FIG. 20, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the second electrode 204, which can be referred to as a contour map. Here, except for the first electrode 202 and the second electrode 204, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers. In FIG. 20 , emission positions of light emitting layers are shown except for the thickness of the second electrode 204 of 1,000 Å, and the thickness of the second electrode 204 does not limit the content of the present invention.

Since the third light emitting layer (EML) 234 constituting the third light emitting part 230 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 234 in the range of 2,050 Å to 2,750 Å, the emission peak 234E of the third light emitting layer (EML) 234 is 440 nm to 480 nm. positioned at nm. For this reason, the third light emitting layer (EML) 234 emits light in the range of 440 nm to 480 nm, thereby achieving maximum efficiency. As already described, in FIG. 20, the light emitting position of the third light emitting layer (EML) 234 is shown as 1,050 Å to 1,750 Å, but this is a value obtained by subtracting 1,000 Å, which is the thickness of the second electrode 204. Accordingly, the light emitting position of the third light emitting layer (EML) 234 may be in the range of 2,050 Å to 2,750 Å from the second electrode 204 . This may be equally applied to the light emitting position of the second light emitting layer (EML) 224 and the light emitting position of the first light emitting layer (EML) 214 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 234 constituting the third light emitting part 230. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 234 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 20 , the third light emitting layer (EML) 234 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 234 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the second light emitting layer (EML) 224 constituting the second light emitting part 220 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 ( peak wavelength range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 224 in the range of 2,850 Å to 3,550 Å, the emission peak 224E of the second light emitting layer (EML) 224 is 510 nm to 580 nm. positioned at nm. Due to this, maximum efficiency can be obtained by emitting light in the range of 510 nm to 580 nm from the second light emitting layer (EML) 224 .

Also, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 224 should emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the second light emitting layer (EML) 224 of the second light emitting part 220 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the second light emitting layer (EML) 224, to achieve maximum efficiency in the white region of the contour map.

Therefore, as the second light emitting layer (EML) 224, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 224 is 510 nm to 650 nm.

In FIG. 20 , an auxiliary light emitting layer is not included in the second light emitting layer (EML) 224, and a yellow-green light emitting layer of the second light emitting layer (EML) 224 is taken as an example, and the light emitting position is shown. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 224 may have maximum efficiency in the range of 510 nm to 580 nm.

Since the first light emitting layer (EML) 214 constituting the first light emitting part 210 is a blue light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 214 is set in the range of 4,450 Å to 5,000 Å so that the emission peak 214E is located at 440 nm to 480 nm. Due to this, maximum efficiency can be obtained by emitting light from the first light emitting layer (EML) 214 in the range of 440 nm to 480 nm.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the first light emitting layer (EML) 214 constituting the first light emitting part 210. In this case, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 214 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 20 , the first light emitting layer (EML) 214 does not include an auxiliary light emitting layer, and the light emitting position of the first light emitting layer (EML) 214 takes a blue light emitting layer as an example. Accordingly, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 214 may produce maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 440 nm to 470 nm, the maximum emission range of the second emission layer is 530 nm to 570 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

21 is a diagram showing an EL spectrum according to a sixth embodiment of the present invention.

In FIG. 21, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 21, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L3 of the third light emitting layer (EML) 234 is in the range of 2,050 Å to 2,750 Å from the second electrode 204, the minimum position is set to 2,050 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L3 of the third light emitting layer (EML) 234 is in the range of 2,050 Å to 2,750 Å from the second electrode 204, the maximum position is set to 2,750 Å.

Example (optimum position) is the part set as the light emitting position of the sixth embodiment of the present invention. For example, when the light emitting position L3 of the third light emitting layer (EML) 234 is in the range of 2,050 Å to 2,750 Å from the second electrode 204, the light emitting position in the embodiment is in the range of 2,050 Å to 2,750 Å. is set to

As shown in FIG. 21, when the minimum position of the light emitting position is out of the EPEL (Emission Position of Emitting Layers) structure of the present invention, a comparison with the optimal position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative examples are shown in Table 11 below. When the efficiency of the comparative example is 100%, the efficiency of the sixth embodiment of the present invention is shown.

In Table 11 below, Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The yellow-green light emitting layer and the third light emitting part are composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 11, when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied compared to the comparative example, if the efficiency of the comparative example is 100%, the red efficiency is increased by about 39%, It can be seen that the green efficiency increased by about 63%. And, it can be seen that the blue efficiency increased by about 47%, and the white efficiency increased by about 61%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 12 below.

Table 12 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 12, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the example (minimum position) and the example (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white is more reduced in the embodiment (maximum position) than in the embodiment (minimum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the sixth embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The position of the first electrode may be set within a range of 4,700 Å to 5,400 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,050 Å to 2,750 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,850 Å to 3,550 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 4,450 Å to 5,000 Å from the first electrode.

The first light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The second light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 440 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 510 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first light-emitting layer is in the range of 440 nm to 470 nm, the maximum emission range of the second light-emitting layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third light-emitting layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

22 is a cross-sectional view of an organic light emitting display device including an organic light emitting device according to an embodiment of the present invention, which includes organic light emitting devices according to the fourth, fifth and sixth embodiments of the present invention described above. it was used

As shown in FIG. 22, the organic light emitting display device 2000 of the present invention includes a substrate 20, a thin film transistor (TFT), a first electrode 202, a light emitting unit 2180, and a second electrode 204. include The thin film transistor (TFT) includes a gate electrode 2115, a gate insulating layer 2120, a semiconductor layer 2131, a source electrode 2133 and a drain electrode 2135.

In FIG. 22 , the thin film transistor (TFT) is shown as an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 20 may be made of glass, metal, or plastic.

A gate electrode 2115 is formed over the substrate 20 and is connected to a gate line (not shown). The gate electrode 2115 is from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a multi-layer made of any selected one or an alloy thereof.

The gate insulating layer 2120 is formed on the gate electrode 2115 and may be a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but is not limited thereto.

The semiconductor layer 2131 is formed on the gate insulating layer 2120, and includes amorphous silicon (a-Si), polycrystalline silicon (poly-Si), an oxide semiconductor, or an organic semiconductor. can be formed as When the semiconductor layer is formed of an oxide semiconductor, it may be formed of indium tin oxide (ITO), indium zinc oxide (IZO), or indium tin zinc oxide (ITZO), but is not limited thereto. An etch stopper (not shown) may be formed on the semiconductor layer 2131 to protect the semiconductor layer 2131, but may be omitted depending on the configuration of the device.

The source electrode 2133 and the drain electrode 2135 may be formed on the semiconductor layer 2131 . The source electrode 2133 and the drain electrode 2135 may be formed of a single layer or multiple layers, and may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), or nickel (Ni). ), any one selected from the group consisting of neodymium (Nd) and copper (Cu), or an alloy thereof.

The protective layer 2140 is formed on the source electrode 2133 and the drain electrode 2135, and may be formed of a silicon oxide film (SiOx), a silicon nitride film (SiNx), or multiple layers thereof. Alternatively, it may be formed of acrylic resin, polyimide resin, etc., but is not limited thereto.

The first electrode 202 is formed on the protective layer 2140 .

In addition, a reflective electrode may be additionally configured below the first electrode 202 to reflect light toward the second electrode 204 . And, an auxiliary electrode may be further configured on the first electrode 202 .

The first electrode 202 is electrically connected to the drain electrode 2135 through a contact hole CH of a predetermined region of the protective layer 2140 . 22 shows that the drain electrode 2135 and the first electrode 202 are electrically connected, but the source electrode 2133 and the first electrode are connected through the contact hole CH of a predetermined area of the protective layer 2140. It is also possible that 202 is electrically connected.

A bank layer 2170 is formed on the first electrode 202 and defines a pixel area. That is, the bank layer 2170 is formed in a matrix structure at a boundary area between a plurality of pixels, so that a pixel area is defined by the bank layer 2170 .

The light emitting part 2180 is formed on the bank layer 2170 . As shown in the fourth, fifth and sixth embodiments of the present invention, the light emitting unit 2180 includes a first light emitting unit, a second light emitting unit and a second light emitting unit formed on the first electrode 202. It consists of 3 light emitting parts.

The second electrode 204 is formed on the light emitting part 2180 . And, a buffer layer may be additionally formed under the second electrode 204 .

An encapsulation layer 2190 is formed on the second electrode 204 . The encapsulation layer 2190 serves to prevent penetration of moisture into the light emitting part 2180 . The encapsulation layer 2190 may include a plurality of layers in which inorganic materials different from each other are stacked, or a plurality of layers in which inorganic materials and organic materials are alternately stacked. The encapsulation substrate 2301 may be bonded to the first substrate 20 by the encapsulation layer 2190 . The encapsulation substrate 2301 may be made of glass, plastic, or metal. A color filter 2302 and a black matrix 2303 are disposed on the encapsulation substrate 2301 . Light emitted from the light emitting unit 2180 travels toward the encapsulation substrate 2301 and displays an image through the color filter 2302 .

In addition, the inventors of the present invention have invented a top emission type white organic light emitting diode having a novel structure in which light emitting efficiency and panel efficiency of the light emitting layer can be improved and luminance and aperture ratio are improved. The inventors of the present invention invented a white organic light emitting device capable of further improving blue efficiency by arranging light emitting layers including light emitting layers emitting the same color adjacent to each other. Also, compared to an organic light emitting display device using a bottom emission method, an organic light emitting display device using a top emission method according to an exemplary embodiment of the present invention may have an improved aperture ratio.

23 is a schematic diagram showing white organic light emitting diodes according to the seventh and eighth embodiments of the present invention.

The white organic light emitting device 300 shown in FIG. 23 includes first and second electrodes 302 and 304 and a first light emitting unit 310 and a second light emitting unit 320 between the first and second electrodes 302 and 304. and a third light emitting unit 330 .

The first electrode 302 is an anode supplying holes. The second electrode 304 is a cathode supplying electrons. The first electrode 302 and the second electrode 304 may be referred to as an anode or a cathode, respectively. The first electrode 302 may be a reflective electrode, and the second electrode 304 may be a transflective electrode.

In the top emission type white organic light emitting device 300 of the present invention, a first light emitting unit 310, a second light emitting unit 320 and A third light emitting unit 330 is included.

In addition, in the white organic light emitting device 300 of the top emission type of the present invention, the position of the second electrode from the first electrode and the light emission positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer are set. Thus, the luminous efficiency and panel efficiency were improved. That is, the first light emitting part, the second light emitting part, and the third light emitting part have a maximum light emitting range in the light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer (Emission Position of Emitting Layers) to have a structure. In addition, two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer include light emitting layers emitting the same color, thereby providing a white organic light emitting device capable of further improving light emitting efficiency. The light emitting layer emitting the same color may be referred to as a light emitting layer including at least one light emitting layer emitting the same color.

The position L0 of the second electrode 304 is set to be positioned within a range of 4,700 Å to 5,400 Å from the first electrode 302 . In addition, the emitting peak of the light emitting layer constituting the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 is located at a specific wavelength, and the light of the specific wavelength By emitting light, the luminous efficiency can be improved. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

The position L0 of the second electrode 304 is set from the first electrode 302, and the light emitting position L1 of the first light emitting part 310 closest to the first electrode 302 ) is set to be 200 Å to 700 Å. Alternatively, the light emitting position (L1) of the first light emitting part 310 is set to be positioned at 200 Å to 700 Å from the reflective surface of the first electrode 302. The first light emitting part 310 may be composed of a yellow-green light emitting layer. Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of organic layers, and the number of organic layers, the first electrode 302 is positioned within a range of 200 Å to 700 Å. Therefore, the first light emitting unit 310 achieves the maximum luminance by emitting light having a wavelength corresponding to the emitting peak and positioning the emitting peak in the yellow-green emitting region. make it possible to pay The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

Also, depending on the characteristics or structure of the device, the first light emitting unit 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, when the red light emitting layer and the green light emitting layer are composed of two layers, the peak wavelength of the light emitting region may be in the range of 510 nm to 660 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

Also, depending on the characteristics or structure of the device, the first light emitting unit 310 may be composed of two layers, a red light emitting layer and a yellow-green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the peak wavelength of the light emitting region may be in the range of 510 nm to 650 nm. In this case, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, depending on the characteristics or structure of the device, the first light emitting unit 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. Peak wavelengths of the light emitting regions of the yellow light emitting layer and the red light emitting layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

The light emitting position L2 of the second light emitting part 320 is set to be positioned within a range of 1,200 Å to 1,800 Å from the first electrode 302 . Alternatively, the light emitting position L2 of the second light emitting part 320 is set to be positioned within a range of 1,200 Å to 1,800 Å from the reflective surface of the first electrode 302 .

The second light emitting part 320 may be composed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light-emitting layer, the number of light-emitting layers, the thickness of organic layers, and the number of organic layers, the light-emitting position L2 of the second light-emitting part 320 is 1,200 Å to 1,800 Å from the first electrode 302. set to be located within the range of Alternatively, the light emitting position L2 of the second light emitting part 320 is set to be positioned within a range of 1,200 Å to 1,800 Å from the reflective surface of the first electrode 302 .

Therefore, the second By positioning the emission peak of the light emitting unit 320 in the blue light emitting region and emitting light of a wavelength corresponding to the emission peak, the second light emitting unit 320 achieves maximum luminance. to be able to pay The peak wavelength of the light emitting region of the blue light emitting layer may be in the range of 440 nm to 480 nm. As an auxiliary light emitting layer, the second light emitting part 320 may be composed of one of a red light emitting layer, a green light emitting layer, and a yellow-green light emitting layer, or a combination thereof. In addition, the peak wavelength of the light emitting region of the light emitting layer constituting the second light emitting part 320 including the auxiliary light emitting layer may be in the range of 440 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L3 of the third light emitting part 330 is set to be positioned within a range of 2,400 Å to 3,100 Å from the first electrode 302 . Alternatively, the light emitting position L3 of the third light emitting part 330 is set to be located within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 302 .

The third light emitting part 330 may be composed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L3 of the third light emitting part 330 is 2,400 Å to 3,100 Å away from the first electrode 302. set to be located within the range of Alternatively, the light emitting position L3 of the third light emitting part 330 is set to be located within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 302 . Therefore, the emitting peak of the third light emitting part 330 is located in the blue light emitting region so that the third light emitting part 330 can emit maximum luminance. The peak wavelength of the light emitting region of the blue light emitting layer may be in the range of 440 nm to 480 nm. As an auxiliary light emitting layer, the third light emitting part 330 may include one or a combination of a red light emitting layer, a green light emitting layer, and a yellow-green light emitting layer. In addition, the peak wavelength of the light emitting region of the light emitting layer constituting the third light emitting part 330 including the auxiliary light emitting layer may be in the range of 440 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

In the present invention, a top emission (top emission) applying an EPEL (Emission Position of Emitting Layers) structure in which the emission position of the light emitting layers is set regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers Emission method relates to a white organic light emitting device. In addition, the first light emitting unit, the second light emitting unit, and the third light emitting unit have an EPEL (Emission Position of Emitting Layers) structure having a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. will be.

24 is a schematic diagram showing a white organic light emitting diode according to a seventh embodiment of the present invention.

The white organic light emitting device 300 shown in FIG. 24 includes a first light emitting unit 310 between the first electrode 302 and the second electrode 304 and the first and second electrodes 302 and 304, and the second light emitting unit 310 . A part 320 and a third light emitting part 330 are provided.

The position of the second electrode 304 is set to be positioned within a range of 4,700 Å to 5,400 Å from the first electrode 302 . By setting the position (L0) of the first electrode 302, emission peaks of the light emitting layers constituting the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength.

The first light-emitting part 310 includes a first hole transport layer (HTL) 312, a first light-emitting layer (EML) 314, and a first electron transport layer (ETL) 316 on the first electrode 302. It can be done by

An auxiliary electrode 303 may be formed on the first electrode 302 . Depending on the characteristics or structure of the device, the auxiliary electrode 303 may not be configured.

Although not shown in the drawing, a hole injection layer (HIL) may be additionally formed on the first electrode 302 .

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 314 . The first electron transport layer (ETL) 316 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 314 . The first hole transport layer (HTL) 312 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 314 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

And, the first light emitting layer (EML) 314 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( It is also possible to configure above or below the EML) (314). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( EML) above and below the 314 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 314 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the first emission layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 314 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 may include two layers of a red light emitting layer and a yellow-green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The first light emitting layer (EML) 314 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When it is composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 312, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 302 and the first light emitting layer (EML) 314 and the auxiliary electrode 303 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 302 and the first light emitting layer (EML) 314 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 312, regardless of the number or thickness of the auxiliary electrodes 303, regardless of the number or thickness of the electron blocking layer (EBL), or the hole injection layer Regardless of the number or thickness of (HIL), regardless of the number or thickness of all organic layers between the first electrode 302 and the first light emitting layer (EML) 314, the first light emitting layer (EML) 314 The light emitting position L1 of is set to be positioned within a range of 200 Å to 700 Å from the first electrode 302 . Alternatively, the light emitting position L1 of the first light emitting layer (EML) 314 is set to be located within a range of 200 Å to 700 Å from the reflective surface of the first electrode 302 . Therefore, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the position L1 of the first light emitting layer (EML) 314 from the first electrode 302 is in the range of 200 Å to 700 Å. It can be set to be located within Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 314 is 200 Å away from the reflective surface of the first electrode 302. to 700 Å.

The second light emitting part 320 may include a second hole transport layer (HTL) 322 , a second light emitting layer (EML) 324 , and a second electron transport layer (ETL) 326 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 322 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 324 . The second electron transport layer (ETL) 326 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 324 . The second hole transport layer (HTL) 322 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 324 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When the second light emitting layer (EML) 324 includes the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the second light emitting layer (EML) 324 . ) It is also possible to configure above or below 324. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer is identically or differently configured above and below the second light emitting layer (EML) 324. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the second light emitting layer (EML) 324, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 340 may be further formed between the first light emitting part 310 and the second light emitting part 320 . The first charge generating layer (CGL) 340 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 314, the first electron transport layer (ETL) 316, the first charge generating layer (CGL) 340, the second hole transport layer 322, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 and the first light emitting layer (EML) 314 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 316, regardless of the number or thickness of the second hole transport layer (HTL) 322, or the first charge generation layer (CGL) 340 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the first light emitting layer (EML) 314, or regardless of the number or thickness of all organic layers between the first electrode 302 and the first light emitting layer (EML) 314, or the Regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324, the light emitting position L2 of the second light emitting layer (EML) 324 is It is set to be positioned within the range of 1,200 Å to 1,800 Å from the first electrode 302 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 324 is set to be positioned within a range of 1,200 Å to 1,800 Å from the reflective surface of the first electrode 302 . Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L2 of the second light emitting layer (EML) 324 from the first electrode 302 may be set to be positioned within a range of 1,200 Å to 1,800 Å. Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L2 of the second light emitting layer (EML) 324 from the reflective surface of the first electrode 302 may be set to be positioned within a range of 1,200 Å to 1,800 Å.

The third light emitting part 330 may include a third electron transport layer (ETL) 336 , a third light emitting layer (EML) 334 , and a third hole transport layer (HTL) 332 . Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 336 .

A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 332 .

A second charge generation layer (CGL) 350 may be further formed between the second light emitting part 320 and the third light emitting part 330 . The second charge generation layer (CGL) 350 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 334 . The third electron transport layer (ETL) 336 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 334 . The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 334 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 334 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 334) is also possible. Also, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 334. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 334, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 324, the second electron transport layer (ETL) 326, the second charge generating layer (CGL) 350, the third hole transport layer 332, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL) and the like can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 and the second light emitting layer (EML) 324 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 may be referred to as a third organic layer.

Regardless of the number or thickness of the second electron transport layer (ETL) 326, regardless of the number or thickness of the second charge generation layer (CGL) 350, or the third hole transport layer (HTL) 332 Regardless of the number or thickness of the second light emitting layer (EML) 324, regardless of the number or thickness of the second light emitting layer (EML) 324, regardless of the number or thickness of the first light emitting layer (EML) 314, or the first electrode 302 ) and the first light emitting layer (EML) 314, regardless of the number or thickness of all organic layers, or all the organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324. The third light emitting layer (EML) ( 334) is set within a range of 2,400 Å to 3,100 Å from the first electrode 302. Alternatively, the light emitting position L3 of the third light emitting layer (EML) 334 is set to be positioned within a range of 2,400 Å to 3,100 Å from the reflective surface of the first electrode 302 . Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Position (L3) of the third light emitting layer (EML) 334 from the first electrode 302 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer may be set to be located within the range of 2,400 Å to 3,100 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first The position of the third light emitting layer (EML) 334 from the reflective surface of the first electrode 302 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer. (L3) may be set to be positioned within a range of 2,400 Å to 3,100 Å.

In addition, all layers such as the third light emitting layer (EML) 334, the third electron transport layer (ETL) 336, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 334 and the second electrode 304, the second electrode 304, and the third light emitting layer (EML) 334 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 334 and the second electrode 304 and including the second electrode 304 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 336, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the second Regardless of the number or thickness of electrodes 304, regardless of the number or thickness of the third light emitting layer (EML) 334, or all of the substrate 301 and the first light emitting layer (EML) 314 Regardless of the number or thickness of organic layers, regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324, or the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 regardless of the number or thickness of all organic layers, or all organic layers between the third light emitting layer (EML) 334 and the second electrode 304 Regardless of the thickness of , the position L0 of the second electrode 304 from the first electrode 302 may be set to be positioned within a range of 4,700 Å to 5,400 Å. Alternatively, the position L0 of the second electrode 304 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 302.

Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 304 may be set to be located within a range of 4,700 Å to 5,400 Å from the first electrode 302 regardless of the thickness of . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The location L0 of the second electrode 304 may be set to be located within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 302 regardless of the thickness of the .

The structure shown in FIG. 24 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

25 is a diagram showing a light emitting position of an organic light emitting device according to a seventh embodiment of the present invention.

In FIG. 25, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 302, which can be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the first light emitting layer (EML) 314 constituting the first light emitting part 310 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 314 is set in the range of 200 Å to 700 Å so that the emission peak 314E is located at 510 nm to 580 nm. For this reason, the maximum efficiency can be achieved by emitting light in the range of 510 nm to 580 nm from the first light emitting layer (EML) 314 .

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the first light emitting layer (EML) 314, so that maximum efficiency can be achieved in the white region of the contour map.

Therefore, as the first light emitting layer (EML) 314, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light is emitted in the light emitting region of 510 nm to 650 nm of the first light emitting layer (EML) 314 .

In FIG. 25 , the first light emitting layer (EML) 314 does not include an auxiliary light emitting layer, and the first light emitting layer (EML) 314 takes a yellow-green light emitting layer as an example, and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 may have maximum efficiency in the range of 510 nm to 580 nm.

Since the second light emitting layer (EML) 324 constituting the second light emitting part 320 is a blue light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 324 in the range of 1,200 Å to 1,800 Å, the emission peak 324E of the second light emitting layer (EML) 324 is 440 nm to 480 nm. positioned at nm. Due to this, maximum efficiency can be achieved by emitting light in the range of 440 nm to 480 nm from the second light emitting layer (EML) 324 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the second light emitting layer (EML) 324 constituting the second light emitting part 320. In this case, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 324 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 25 , the second light emitting layer (EML) 324 does not include an auxiliary light emitting layer, and the second light emitting layer (EML) 324 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the third light emitting layer (EML) 334 constituting the third light emitting part 330 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 334 in the range of 2,400 Å to 3,100 Å, the emission peak 334E of the third light emitting layer (EML) 334 is 440 nm to 480 nm. positioned at nm. Due to this, the third light emitting layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 334 constituting the third light emitting part 330. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 334 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 25 , the third light emitting layer (EML) 334 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 334 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may have maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 530 nm to 570 nm, the maximum emission range of the second emission layer is 440 nm to 470 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

26 is a diagram showing an EL spectrum according to a seventh embodiment of the present invention.

* In FIG. 26, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 26, the embodiment (minimum position) is the part set as the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the minimum position is set to 200 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 202, the maximum position is set to 700 Å.

Example (optimum position) is the part set as the light emitting position of the seventh embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the light emitting position in the embodiment is set to the range of 200 Å to 700 Å. .

As shown in FIG. 26, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, when the minimum position of the light emitting position is out of position, a comparison with the optimal position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 13 below. When the efficiency of the comparative example is 100%, the efficiency of the seventh embodiment of the present invention is shown.

Table 13 below compares the efficiencies of Comparative Examples and Examples of the present invention. Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( Yellow-Green) light emitting layer, and the third light emitting part is composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 13, when the EPEL structure of the present invention is applied compared to the comparative example, when the efficiency of the comparative example is 100%, the red efficiency is increased by about 77%, and the green efficiency is 64 It can be seen that there is an increase of %. And, it can be seen that the blue efficiency increased by about 51%, and the white efficiency increased by about 68%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 14 below.

Table 14 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 14, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the seventh embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

A light emitting position of the first light emitting layer may be set in a range of 200 Å to 700 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,200 Å to 1,800 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,400 Å to 3,100 Å from the first electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

27 is a schematic diagram showing a white organic light emitting device according to an eighth embodiment of the present invention. In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted.

The white organic light emitting device 300 shown in FIG. 27 has a first light emitting unit 310 between the first electrode 302 and the second electrode 304 and the first and second electrodes 302 and 304, and the second light emitting unit 310 . A part 320 and a third light emitting part 330 are provided.

Referring to FIG. 27 , the position of the second electrode 304 is set to be located at 4,700 Å to 5,400 Å from the first electrode 302 . By setting the position (L0) of the first electrode 302, emission peaks of the light emitting layers constituting the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength. That is, the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 have an EPEL having a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. (Emission Position of Emitting Layers) structure. Two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer may include light emitting layers emitting the same color, thereby providing a white organic light emitting device capable of further improving light emitting efficiency. The light emitting layer emitting the same color may be referred to as a light emitting layer including at least one light emitting layer emitting the same color.

The first light-emitting part 310 includes a first hole transport layer (HTL) 312, a first light-emitting layer (EML) 314, and a first electron transport layer (ETL) 316 on the first electrode 302. It can be done by

An auxiliary electrode 303 may be formed on the first electrode 302 . In addition, the auxiliary electrode 203 may not be configured depending on the characteristics or structure of the device.

Although not shown in the drawing, a hole injection layer (HIL) may be additionally formed on the first electrode 302 .

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 314 .

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 314 .

The first light emitting layer (EML) 314 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be a light emitting region.

And, the first light emitting layer (EML) 314 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( It is also possible to configure above or below the EML) (314). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( EML) above and below the 314 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 314 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the first emission layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 314 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 may include two layers of a red light emitting layer and a yellow-green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The first light emitting layer (EML) 314 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When it is composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 312, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 302 and the first light emitting layer (EML) 314 and the auxiliary electrode 303 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 302 and the first light emitting layer (EML) 314 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 312, regardless of the number or thickness of the auxiliary electrodes 303, regardless of the number or thickness of the electron blocking layer (EBL), or the hole injection layer Regardless of the number or thickness of (HIL), regardless of the number or thickness of all organic layers between the first electrode 302 and the first light emitting layer (EML) 314, the first light emitting layer (EML) 314 The light emitting position L1 of is set to be positioned within a range of 200 Å to 700 Å from the first electrode 302 . Alternatively, the light emitting position L1 of the first light emitting layer (EML) 314 is set to be located within a range of 200 Å to 700 Å from the reflective surface of the first electrode 302 .

Therefore, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the position L1 of the first light emitting layer (EML) 314 from the first electrode 302 is in the range of 200 Å to 700 Å. It can be set to be located within Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 314 is 200 Å away from the reflective surface of the first electrode 302. to 700 Å.

The second light emitting part 320 may include a second hole transport layer (HTL) 322 , a second light emitting layer (EML) 324 , and a second electron transport layer (ETL) 326 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 322 .

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 324 . The second electron transport layer (ETL) 326 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 324 . The second hole transport layer (HTL) 322 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 324 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When the second light emitting layer (EML) 324 includes the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the second light emitting layer (EML) 324 . ) It is also possible to configure above or below 324. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer is identically or differently configured above and below the second light emitting layer (EML) 324. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the second light emitting layer (EML) 324, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 340 may be further formed between the first light emitting part 310 and the second light emitting part 320 . The first charge generating layer (CGL) 340 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 314, the first electron transport layer (ETL) 316, the first charge generating layer (CGL) 340, the second hole transport layer 322, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 and the first light emitting layer (EML) 314 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 316, regardless of the number or thickness of the second hole transport layer (HTL) 322, or the first charge generation layer (CGL) 340 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the first light emitting layer (EML) 314, or regardless of the number or thickness of all organic layers between the first electrode 302 and the first light emitting layer (EML) 314, or the Regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324, the light emitting position L2 of the second light emitting layer (EML) 324 is It is set to be positioned within the range of 1,250 Å to 1,750 Å from the first electrode 302 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 324 is set to be positioned within a range of 1,250 Å to 1,750 Å from the reflective surface of the first electrode 302 .

Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the A position L2 of the second light emitting layer (EML) 324 from the first electrode 302 may be set to be positioned within a range of 1,250 Å to 1,750 Å. Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The position L2 of the second light emitting layer (EML) 324 from the reflective surface of the first electrode 202 may be set to be positioned within a range of 1,250 Å to 1,750 Å.

The third light emitting part 330 may include a third electron transport layer (ETL) 336 , a third light emitting layer (EML) 334 , and a third hole transport layer (HTL) 332 . Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 336 . A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 332 . A second charge generation layer (CGL) 350 may be further formed between the second light emitting part 320 and the third light emitting part 330 . The second charge generation layer (CGL) 350 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 334 . The third electron transport layer (ETL) 336 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 334 . The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 334 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved.

When configuring the third light emitting layer (EML) 334 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 334) is also possible. Also, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 334. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 334, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

The second light emitting layer (EML) 324, the second electron transport layer (ETL) 326, the second charge generating layer (CGL) 350, the third hole transport layer 332, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL) and the like can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 and the second light emitting layer (EML) 324 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 may be referred to as a third organic layer.

Regardless of the number or thickness of the second electron transport layer (ETL) 326, regardless of the number or thickness of the second charge generation layer (CGL) 350, or the third hole transport layer (HTL) 332 Regardless of the number or thickness of the second light emitting layer (EML) 324, regardless of the number or thickness of the second light emitting layer (EML) 324, regardless of the number or thickness of the first light emitting layer (EML) 314, or the first electrode 302 ) and the first light emitting layer (EML) 314, regardless of the number or thickness of all organic layers, or all the organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324. The third light emitting layer (EML) ( 334) is set within a range of 2,500 Å to 3,000 Å from the first electrode 302. Alternatively, the light emitting position L3 of the third light emitting layer (EML) 334 is set to be positioned within a range of 2,500 Å to 3,000 Å from the reflective surface of the first electrode 302 .

Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Position (L3) of the third light emitting layer (EML) 334 from the first electrode 302 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer may be set to be located within a range of 2,500 Å to 3,000 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first The position of the third light emitting layer (EML) 334 from the reflective surface of the first electrode 302 regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer. (L3) may be set to be positioned within a range of 2,500 Å to 3,000 Å.

In addition, all layers such as the third light emitting layer (EML) 334, the third electron transport layer (ETL) 336, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 334 and the second electrode 304, the second electrode 304, and the third light emitting layer (EML) 334 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 334 and the second electrode 304 and including the second electrode 304 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 336, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the second Regardless of the number or thickness of electrodes 304, regardless of the number or thickness of the third light emitting layer (EML) 334, or all of the substrate 301 and the first light emitting layer (EML) 314 Regardless of the number or thickness of organic layers, regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324, or the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334 regardless of the number or thickness of all organic layers, or all organic layers between the third light emitting layer (EML) 334 and the second electrode 304 Regardless of the thickness of , the position L0 of the second electrode 304 from the first electrode 302 may be set to be positioned within a range of 4,700 Å to 5,400 Å. Alternatively, the position L0 of the second electrode 304 may be set to be located within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 302 .

Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer Regardless of the thickness of , the position L0 of the second electrode 304 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the first electrode 302 . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The location L0 of the second electrode 304 may be set to be located within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 302 regardless of the thickness of the .

The structure shown in FIG. 27 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

28 is a view showing a light emitting position of an organic light emitting device according to an eighth embodiment of the present invention.

In FIG. 28, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 302, which can be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the first light emitting layer (EML) 314 constituting the first light emitting part 310 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 314 is set in the range of 200 Å to 700 Å so that the emission peak 314E is located at 510 nm to 580 nm. For this reason, the maximum efficiency can be achieved by emitting light in the range of 510 nm to 580 nm from the first light emitting layer (EML) 314 .

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the first light emitting layer (EML) 314, so that maximum efficiency can be achieved in the white region of the contour map.

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

Therefore, as the first light emitting layer (EML) 314, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light is emitted in the light emitting region of 510 nm to 650 nm of the first light emitting layer (EML) 314 .

In FIG. 28 , the first light emitting layer (EML) 314 does not include an auxiliary light emitting layer, and the first light emitting layer (EML) 314 takes a yellow-green light emitting layer as an example, and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 314 may have maximum efficiency in the range of 510 nm to 580 nm.

Since the second light emitting layer (EML) 324 constituting the second light emitting part 320 is a blue light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 324 in the range of 1,250 Å to 1,750 Å, the emission peak 324E of the second light emitting layer (EML) 324 is 440 nm to 480 nm. positioned at nm. Due to this, maximum efficiency can be achieved by emitting light in the range of 440 nm to 480 nm from the second light emitting layer (EML) 324 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the second light emitting layer (EML) 324 constituting the second light emitting part 320. In this case, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 324 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 28 , the second light emitting layer (EML) 324 does not include an auxiliary light emitting layer, and the second light emitting layer (EML) 324 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the third light emitting layer (EML) 334 constituting the third light emitting part 330 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 334 in the range of 2,500 Å to 3,000 Å, the emission peak 334E of the third light emitting layer (EML) 334 is 440 nm to 480 nm. positioned at nm. Due to this, the third light emitting layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 334 constituting the third light emitting part 330. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 334 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 28 , the third light emitting layer (EML) 334 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 334 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may have maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 530 nm to 570 nm, the maximum emission range of the second emission layer is 440 nm to 470 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

29 is a diagram showing an EL spectrum according to an eighth embodiment of the present invention.

In FIG. 29, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the minimum position is set to 200 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the maximum position is set to 700 Å.

Example (optimal position) is the part set as the light emitting position of the eighth embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the light emitting position in the embodiment is set to the range of 200 Å to 700 Å. .

As shown in FIG. 29, when the minimum position of the light emitting position is out of the EPEL (Emission Position of Emitting Layers) structure of the present invention, a comparison with the optimal position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 15 below. When the efficiency of the comparative example is 100%, the efficiency of the eighth embodiment of the present invention is shown.

Table 15 below compares the efficiencies of Comparative Examples and Examples of the present invention. Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( Yellow-Green) light emitting layer, and the third light emitting part is composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 15, when the EPEL structure of the present invention is applied compared to the comparative example, when the efficiency of the comparative example is 100%, the red efficiency is increased by about 77%, and the green efficiency is 64 It can be seen that there is an increase of %. And, it can be seen that the blue efficiency increased by about 51%, and the white efficiency increased by about 68%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 16 below.

Table 16 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 16, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . And, comparing Table 14 of the seventh embodiment of the present invention with Table 16 of the eighth embodiment of the present invention, green and blue colors are displayed at the boundary between the embodiment (minimum position) and the embodiment (maximum position). ) and white efficiency were further improved. Accordingly, according to the eighth exemplary embodiment of the present invention, an organic light emitting display device with further improved efficiency can be provided. In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the eighth embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the second electrode may be set within a range of 4,700 Å to 5,400 Å from the first electrode.

A light emitting position of the first light emitting layer may be set in a range of 200 Å to 700 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,250 Å to 1,750 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,500 Å to 3,000 Å from the first electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

30 is a schematic diagram showing a white organic light emitting device according to a ninth embodiment of the present invention. In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted. In this embodiment, the light emitting position of the light emitting layers is set from the second electrode, and the light emitting position can be set from the second electrode according to device design.

The white organic light emitting device 300 shown in FIG. 30 includes a first light emitting unit 310 between the first electrode 302 and the second electrode 304, and the first and second electrodes 302 and 304, and the second light emitting unit 310. A portion 320 and a third light emitting portion 330 are provided. The location of the second electrode 304 is set to be located within a range of 4,700 Å to 5,400 Å from the first electrode 302 . By setting the position (L0) of the first electrode 302, emission peaks of the light emitting layers constituting the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength. In addition, the first light emitting part, the second light emitting part, and the third light emitting part have a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer (EPEL) (Emission Position of Emitting Layers) to have a structure. In addition, in this embodiment, two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer are configured to include light emitting layers emitting the same color, thereby providing a white organic light emitting device capable of further improving light emitting efficiency. do. The light emitting layer emitting the same color may be referred to as a light emitting layer including at least one light emitting layer emitting the same color.

The third light emitting part 330 may include a third electron transport layer (ETL) 336 , a third light emitting layer (EML) 334 , and a third hole transport layer (HTL) 332 . Although not shown in the drawing, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 336 . A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 332 . A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 334 . The third electron transport layer (ETL) 336 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 334 . The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 334 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 334 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML) ( 334) is also possible. Also, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 334. It is possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 334, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the third electron transport layer (ETL) 336, the third light emitting layer (EML) 334, the electron injection layer (EIL), and the hole blocking layer (HBL) may be referred to as organic layers. All organic layers positioned between the second electrode 304 and the third light emitting layer (EML) 334 and the second electrode 304 and the third light emitting layer (EML) 334 may be referred to as organic layers. . Accordingly, all organic layers positioned between the second electrode 304 and the third light emitting layer (EML) 334 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 336, regardless of the number or thickness of the third light emitting layer (EML) 334, or regardless of the number or thickness of the electron injection layer (EIL), Alternatively, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of the second electrodes 304, or between the second electrode 304 and the third light emitting layer (EML) 334 Regardless of the number or thickness of all the organic layers present, the light emitting position L3 of the third light emitting layer (EML) 334 is set to be positioned within a range of 2,050 Å to 2,750 Å from the second electrode 304 . Therefore, regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layers, and the thickness of the third light emitting layer, the third light emitting layer EML is formed from the second electrode 304. The position (L3) of (334) can be set to be located within the range of 2,050Å to 2,750Å.

The second light emitting part 320 may include a second hole transport layer (HTL) 322 , a second light emitting layer (EML) 324 , and a second electron transport layer (ETL) 326 .

A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 322 . A hole blocking layer (HBL) may be further formed over the second light emitting layer (EML) 324 . have. The second electron transport layer (ETL) 326 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the second light emitting layer (EML) 324 . The second hole transport layer (HTL) 322 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 324 is composed of a blue light emitting layer including a blue light emitting layer or an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When the second light emitting layer (EML) 324 includes the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the second light emitting layer (EML) 324 . ) It is also possible to configure above or below 324. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer is identically or differently configured above and below the second light emitting layer (EML) 324. It is also possible. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the second light emitting layer (EML) 324, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 350 may be further formed between the second light emitting part 320 and the third light emitting part 330. This second charge generating layer (CGL) 350 is N A type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL) may be included.

The second light emitting layer (EML) 324, the second electron transport layer (ETL) 326, the second charge generating layer (CGL) 250, the third hole transport layer (HTL) 332, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 334 and the second light emitting layer (EML) 324 and the second light emitting layer (EML) 324 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 334 and the second light emitting layer (EML) 324 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layer (HTL) 332, regardless of the number or thickness of the second electron transport layer (ETL) 326, or the second charge generation layer (CGL) 350 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the third light emitting layer (EML) 334, regardless of the number or thickness of the second light emitting layer (EML) 324, or the second electrode 304 and the third light emitting layer (EML) ) 334, regardless of the number or thickness of all organic layers, or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334, The light emitting position L2 of the second light emitting layer (EML) 324 is set to be positioned within a range of 3,350 Å to 3,950 Å from the second electrode 304 . Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the position L2 of the second light emitting layer (EML) 324 from the second electrode 304 may be set to be located within a range of 3,350 Å to 3,950 Å. .

The first light-emitting part 310 includes a first hole transport layer (HTL) 312, a first light-emitting layer (EML) 314, and a first electron transport layer (ETL) 316 on the first electrode 302. It can be done by

An auxiliary electrode 303 may be formed on the first electrode 302 . In addition, the auxiliary electrode 203 may not be configured depending on the characteristics or structure of the device.

Although not shown in the drawing, a hole injection layer (HIL) may be additionally formed on the first electrode 302 .

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 314 . The first electron transport layer (ETL) 316 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 314 . The first hole transport layer (HTL) 312 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 314 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm.

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved. In addition, when the red light emitting layer and the green light emitting layer are composed of two layers, the peak wavelength of the light emitting region may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In addition, the peak wavelength range of the light emitting layer including red light as an auxiliary light emitting layer in the yellow-green light emitting layer may be 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

In addition, depending on the characteristics or structure of the device, the first light emitting unit 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. Peak wavelengths of the light emitting regions of the yellow light emitting layer and the red light emitting layer may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

A first charge generating layer (CGL) 340 may be further formed between the first light emitting part 310 and the second light emitting part 320 . The charge generating layer 340 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 314, the first electron transport layer (ETL) 316, the first charge generating layer (CGL) 340, the second hole transport layer 322, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 and the first light emitting layer (EML) 314 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 316, or the second

Regardless of the number or thickness of hole transport layers (HTL) 322, or regardless of the number or thickness of the first charge generation layer (CGL) 340, or regardless of the number or thickness of hole blocking layers (HBL), or Regardless of the number or thickness of electron blocking layers (EBL), regardless of the number or thickness of hole injection layers (HIL), regardless of the number or thickness of the third light emitting layer (EML) 334, or the second light emitting layer Regardless of the number or thickness of the (EML) 324, regardless of the number or thickness of the first light emitting layer (EML) 314, or the second electrode 304 and the third light emitting layer (EML) 334 Regardless of the number or thickness of all organic layers interposed therebetween, or regardless of the number or thickness of all organic layers interposed between the second light emitting layer (EML) 324 and the third light emitting layer (EML) 334, or the first Regardless of the number or thickness of all organic layers between the light emitting layer (EML) 314 and the second light emitting layer (EML) 324, the light emitting position L1 of the first light emitting layer (EML) 314 is the second light emitting layer (EML) 314. It is set to be positioned within the range of 4,450 Å to 4,950 Å from the electrode 304 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the second electrode 304 The position L1 of the first light emitting layer (EML) 314 may be set to be positioned within a range of 4,450 Å to 4,950 Å.

All layers such as the first hole transport layer (HTL) 312, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first electrode 302 and the first light emitting layer (EML) 314 and the auxiliary electrode 303 may be referred to as organic layers. Accordingly, all organic layers between the first electrode 302 and the first light emitting layer (EML) 314 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layer (HTL) 312, regardless of the number or thickness of the auxiliary electrodes 303, regardless of the number or thickness of the electron blocking layer (EBL), or the hole injection layer Regardless of the number or thickness of the HIL, regardless of the number or thickness of the third light emitting layer (EML) 334, regardless of the number or thickness of the second light emitting layer (EML) 324, or the first Regardless of the number or thickness of the light emitting layers (EML) 314, or regardless of the number or thickness of all organic layers between the second electrode 304 and the third light emitting layer (EML) 334, or the second light emitting layer Regardless of the number or thickness of all organic layers between the (EML) 324 and the third light emitting layer (EML) 334, or between the first light emitting layer (EML) 314 and the second light emitting layer (EML) 324 ), regardless of the number or thickness of all organic layers between the first electrode 302 and the first light emitting layer (EML) 314, regardless of the number or thickness of all organic layers, the second electrode 304 ), the position L0 of the first electrode 302 may be set to be positioned within a range of 4,700 Å to 5,400 Å.

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, the first The number of organic layers, the thickness of the first organic layer, the number of the third light-emitting layers, the thickness of the third light-emitting layer, the number of the second light-emitting layers, the thickness of the second light-emitting layer, the number of the first light-emitting layers, the first light-emitting layer The position L0 of the first electrode 302 from the second electrode 304 may be set to be positioned within a range of 4,700 Å to 5,400 Å regardless of the thickness of .

Here, the light emitting position L1 of the first light emitting layer (EML) 314 may be set to be positioned within a range of 4,450 Å to 4,950 Å from the second electrode 304 . Also, the position L0 of the first electrode 302 may be set to be positioned within a range of 4,700 Å to 5,400 Å from the second electrode 304 . When the light emitting position L1 of the first light emitting layer (EML) 314 is set to 4,950 Å from the second electrode 304, the position L0 of the first electrode 302 is the second electrode ( 304) may be set to be positioned within a range of 5,000 Å to 5,400 Å.

Accordingly, the present invention provides at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, The number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, Regardless of the thickness of the third light emitting layer, the position of the first electrode 302 and the light emitting layers may be set from the second electrode 304.

The structure shown in FIG. 30 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

31 is a view showing a light emitting position of an organic light emitting device according to a ninth embodiment of the present invention.

In FIG. 31, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 302, which can be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, the emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers. In FIG. 31 , except for the thickness of the second electrode 304 of 1,000 Å, emission positions of the light emitting layers are shown, and the thickness of the second electrode 304 does not limit the contents of the present invention.

Since the third light emitting layer (EML) 334 constituting the third light emitting part 330 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer. As already described, in FIG. 31, the light emission position of the third light emitting layer (EML) 334 is shown as 1,050 Å to 1,750 Å, but this is a value obtained by subtracting 1,000 Å, which is the thickness of the second electrode 304. Accordingly, the light emitting position of the third light emitting layer (EML) 334 may be in the range of 2,050 Å to 2,750 Å from the second electrode 304 . This may be equally applied to the light emitting position of the second light emitting layer (EML) 324 and the light emitting position of the first light emitting layer (EML) 314 .

Therefore, by setting the emission position of the third light emitting layer (EML) 334 in the range of 2,050 Å to 2,750 Å, the emission peak 334E of the third light emitting layer (EML) 334 is 440 nm to 480 nm. positioned at nm. Due to this, the third light emitting layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 334 constituting the third light emitting part 330. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 334 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 31 , the third light emitting layer (EML) 334 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 334 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 334 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the second light emitting layer (EML) 324 constituting the second light emitting part 320 is a blue light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 324 in the range of 3,350 Å to 3,950 Å, the emission peak 324E of the second light emitting layer (EML) 324 is 440 nm to 480 nm. positioned at nm. Due to this, maximum efficiency can be achieved by emitting light in the range of 440 nm to 480 nm from the second light emitting layer (EML) 324 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the second light emitting layer (EML) 324 constituting the second light emitting part 320. In this case, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 324 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 324 should emit light in the range of 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 31 , the second light emitting layer (EML) 324 does not include an auxiliary light emitting layer, and the second light emitting layer (EML) 324 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 324 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the first light emitting layer (EML) 314 constituting the first light emitting part 310 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the first light emitting layer (EML) 314 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 314 is set in the range of 200 Å to 700 Å so that the emission peak 314E is located at 510 nm to 580 nm. For this reason, the maximum efficiency can be achieved by emitting light in the range of 510 nm to 580 nm from the first light emitting layer (EML) 314 .

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 314 should be emitted in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 314 of the first light emitting part 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, it is necessary to emit light at 540 nm to 650 nm, which is the light emitting region of the first light emitting layer (EML) 314, so that maximum efficiency can be achieved in the white region of the contour map.

Therefore, as the first light emitting layer (EML) 314, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light is emitted in the light emitting region of 510 nm to 650 nm of the first light emitting layer (EML) 314 .

In FIG. 31 , the first light emitting layer (EML) 314 does not include an auxiliary light emitting layer, and the first light emitting layer (EML) 314 takes a yellow-green light emitting layer as an example, and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 314 may have maximum efficiency in the range of 510 nm to 580 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 530 nm to 570 nm, the maximum emission range of the second emission layer is 440 nm to 470 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

32 is a diagram showing an EL spectrum according to a ninth embodiment of the present invention.

In FIG. 32, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 32, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L3 of the third light emitting layer (EML) 334 is in the range of 2,050 Å to 2,750 Å from the second electrode 304, the minimum position is set to 2,050 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L3 of the third light emitting layer (EML) 334 is in the range of 2,050 Å to 2,750 Å from the second electrode 304, the maximum position is set to 2,750 Å.

Example (optimal position) is the part set as the light emitting position of the eighth embodiment of the present invention. For example, when the light emitting position L3 of the third light emitting layer (EML) 334 is in the range of 2,050 Å to 2,750 Å from the second electrode 304, the light emitting position in the embodiment is 2,050 Å to 2,750 Å. set as a range.

As shown in FIG. 32, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, when the minimum light emitting position is out of position, a comparison with the optimal position is as follows. It can be seen that the luminescence intensity decreases in the peak wavelength range of blue light, 440 nm to 480 nm, and is out of the peak wavelength range of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the emission position of emitting layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 17 below. When the efficiency of the comparative example is 100%, the efficiency of the ninth embodiment of the present invention is shown.

Table 17 below compares the efficiencies of Comparative Examples and Examples of the present invention. Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( Yellow-Green) light emitting layer, and the third light emitting part is composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 17, when the EPEL structure of the present invention is applied compared to the comparative example, when the efficiency of the comparative example is 100%, the red efficiency is increased by about 77%, and the green efficiency is 64 It can be seen that there is an increase of %. And, it can be seen that the blue efficiency increased by about 51%, and the white efficiency increased by about 68%.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 16 below.

Table 18 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimal position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 18, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (maximum position) is more reduced than in the embodiment (minimum position).

Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the eighth embodiment of the present invention, the organic light emitting device may be a top emission type organic light emitting device.

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the first electrode may be set within a range of 4,700 Å to 5,400 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 2,050 Å to 2,750 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 3,350 Å to 3,950 Å from the second electrode.

An emission position of the first emission layer may be set within a range of 4,450 Å to 4,950 Å from the second electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

33 is a cross-sectional view of an organic light emitting display device including an organic light emitting device according to an embodiment of the present invention, which includes organic light emitting devices according to the seventh, eighth, and ninth embodiments of the present invention described above. it was used In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted.

As shown in FIG. 33, the organic light emitting display device 3000 of the present invention includes a substrate 30, a thin film transistor (TFT), a first electrode 302, a light emitting part 3180, and a second electrode 304. include The thin film transistor (TFT) includes a gate electrode 3115, a gate insulating layer 3120, a semiconductor layer 3131, a source electrode 3133 and a drain electrode 3135.

In FIG. 33, the thin film transistor (TFT) is shown as an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 30 may be made of glass, metal, or plastic.

A gate electrode 3115 is formed over the substrate 30 .

A gate insulating layer 3120 is formed over the gate electrode 3115 .

A semiconductor layer 3131 is formed over the gate insulating layer 3120 .

The source electrode 3133 and the drain electrode 3135 may be formed on the semiconductor layer 3131 .

A protective layer 3140 is formed on the source electrode 3133 and the drain electrode 3135 .

The first electrode 302 is formed on the protective layer 3140.

In addition, a reflective electrode may be additionally configured under the first electrode 302 to reflect light toward the second electrode 304 . Also, an auxiliary electrode may be further configured on the first electrode 302 .

The first electrode 302 is electrically connected to the drain electrode 3135 through a contact hole CH of a predetermined region of the protective layer 3140 .

A bank layer 3170 is formed on the first electrode 302 and defines a pixel area.

The light emitting part 3180 is formed on the bank layer 3170 . As shown in the seventh, eighth and ninth embodiments of the present invention, the light emitting unit 3180 includes a first light emitting unit, a second light emitting unit and a second light emitting unit formed on the first electrode 302. It consists of 3 light emitting parts.

The second electrode 304 is formed on the light emitting part 3180 .

An encapsulation layer 3190 is formed on the second electrode 304 . The encapsulation substrate 3301 may be bonded to the first substrate 30 by the encapsulation layer 3190 . The encapsulation substrate 3301 may be made of glass, plastic, or metal. A color filter 3302 and a black matrix 3303 are disposed on the encapsulation substrate 3301 . Light emitted from the light emitting unit 3180 travels toward the encapsulation substrate 3301 and displays an image through the color filter 3302 .

In addition, the inventors of the present invention invented a bottom emission type white organic light emitting diode having a novel structure in which the light emitting efficiency and panel efficiency of the light emitting layer can be improved and the luminance is improved. The inventors of the present invention invented a white organic light emitting device capable of further improving blue efficiency by arranging light emitting layers including light emitting layers emitting the same color adjacent to each other.

34 is a schematic diagram showing a white organic light emitting device according to a tenth embodiment of the present invention.

The white organic light emitting device 400 shown in FIG. 34 includes first and second electrodes 402 and 404, and a first light emitting unit 410 disposed between the first and second electrodes 402 and 404, and a second light emitting unit ( 420) and a third light emitting unit 430.

The first electrode 402 is an anode supplying holes. The second electrode 404 is a cathode supplying electrons. The first electrode 402 and the second electrode 404 may be referred to as an anode or a cathode, respectively. The first electrode may be a transmissive electrode, and the second electrode may be a reflective electrode.

The present invention is to improve light emitting efficiency and panel efficiency by setting the position of the first electrode from the second electrode and setting the light emitting positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. That is, the first light emitting part, the second light emitting part, and the third light emitting part have a maximum light emitting range in the light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer (Emission Position of Emitting Layers) to have a structure. In addition, two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer include light emitting layers emitting the same color, thereby providing a white organic light emitting device capable of further improving light emitting efficiency. The light emitting layer emitting the same color may be referred to as a light emitting layer including at least one light emitting layer emitting the same color.

The position L0 of the first electrode 402 is set to be positioned within a range of 3,500 Å to 4,500 Å from the second electrode 404 . Alternatively, the position L0 of the first electrode 402 is set to be located within a range of 3,500 Å to 4,500 Å from the reflective surface of the second electrode 404 . In addition, emitting peaks of the light emitting layers constituting the first light emitting unit 410, the second light emitting unit 420, and the third light emitting unit 430 are positioned at a specific wavelength, and light of the specific wavelength is positioned. By emitting light, the luminous efficiency can be improved. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

The position L0 of the first electrode 402 is set from the second electrode 404, and the light emitting position L1 of the third light emitting part 430 closest to the second electrode 404 ) is set to be located within the range of 250 Å to 800 Å. Alternatively, the light emitting position L1 of the third light emitting part 430 is set to be located within a range of 250 Å to 800 Å from the reflective surface of the second electrode 404 . The third light emitting unit 430 may include a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer (Blue light emitting layer). ) and a green light emitting layer, or a combination thereof. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L1 of the third light emitting part 430 is 250 Å to 800 Å away from the second electrode 404. be placed within the range. Alternatively, the light emitting position L1 of the third light emitting part 430 is set to be 250 Å to 800 Å from the reflective surface of the second electrode 404 . Therefore, the emitting peak is positioned in the blue emitting region and the third light emitting unit 430 emits maximum luminance by emitting light of a wavelength corresponding to the emitting peak. . A peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, the peak wavelength range of the blue light emitting layer and the yellow-green light emitting layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue light emitting layer and the red light emitting layer may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue light emitting layer and the green light emitting layer may be 440 nm to 560 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L2 of the second light emitting part 420 is set to be located within a range of 1,450 Å to 1,950 Å from the second electrode 404 . Alternatively, the light emitting position L2 of the second light emitting part 420 is set to be positioned within a range of 1,450 Å to 1,950 Å from the reflective surface of the second electrode 404 . The second light emitting unit 420 may include a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer (Blue light emitting layer). ) and a green light emitting layer, or a combination thereof. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L2 of the second light emitting part 420 is 1,450 Å to 1,950 Å from the second electrode 404 Set it to be located within the range of Å. Alternatively, the light emitting position L1 of the second light emitting part 420 is set to be positioned within a range of 1,450 Å to 1,950 Å from the reflective surface of the second electrode 404 .

Therefore, the emission peak is positioned in the blue emission region and the second light emitting unit 420 emits maximum luminance by emitting light of a wavelength corresponding to the emission peak. . A peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, the peak wavelength range of the blue light emitting layer and the yellow-green light emitting layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue light emitting layer and the red light emitting layer may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue light emitting layer and the green light emitting layer may be 440 nm to 560 nm. Here, the peak wavelength may be a light emitting region.

The light emitting position L3 of the first light emitting part 410 is set to be 2,050 Å to 2,600 Å from the second electrode 404 . Alternatively, the light emitting position L3 of the first light emitting part 410 is set to be located within a range of 2,050 Å to 2,600 Å from the reflective surface of the second electrode 404 . The first light emitting unit 410 may include a yellow-green light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a yellow-green ( It may consist of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof.

Regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of the organic layer, and the number of organic layers, the light emitting position L3 of the first light emitting part 420 is 2,050 Å to 2,600 Å from the second electrode 404 Set it to be located within the range of Å. Alternatively, the light emitting position L3 of the first light emitting part 420 is set to be positioned within a range of 2,050 Å to 2,600 Å from the reflective surface of the second electrode 404 .

Therefore, the emission peak is located in the yellow-green emission region, or the yellow and red emission region, or the red and green emission region, or the yellow-green and red emission region, and the emission peak ( By emitting light of a wavelength corresponding to an emitting peak, the first light emitting unit 110 can generate maximum luminance. A peak wavelength range of the yellow-green light emitting layer may be 510 nm to 580 nm. And, the peak wavelength range of the yellow light emitting layer and the red light emitting layer may be 540 nm to 650 nm. In addition, the peak wavelength range of the red light emitting layer and the green light emitting layer may be 510 nm to 650 nm. In addition, the peak wavelength range of the yellow-green light emitting layer and the red light emitting layer may be 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The present invention sets the position of the first electrode 402 from the second electrode 404 regardless of at least one of the thickness of the light emitting layer, the number of light emitting layers, the thickness of organic layers, and the number of organic layers, and the second An Emission Position of Emitting Layers (EPEL) structure in which light emission positions of the light emitting layers are set from the electrode 404 is applied. In addition, the first light emitting unit, the second light emitting unit, and the third light emitting unit have an EPEL (Emission Position of Emitting Layers) structure having a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer. will be.

35 is a view showing a white organic light emitting device according to a tenth embodiment of the present invention.

The white organic light emitting device 400 shown in FIG. 35 includes first and second electrodes 402 and 404 and a first light emitting unit 410 and a second light emitting unit 420 between the first and second electrodes 402 and 404 . and a third light emitting unit 430 .

The first electrode 402 and the second electrode 404 may be referred to as an anode or a cathode, respectively.

The first electrode may be a transmissive electrode, and the second electrode may be a reflective electrode.

The first electrode 402 is positioned within a range of 3,500 Å to 4,500 Å from the second electrode 404 . By setting the position (L0) of the first electrode 402, emission peaks of the light emitting layers constituting the first light emitting part 410, the second light emitting part 420, and the third light emitting part 430 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength.

The third light emitting part 430 includes a third electron transport layer (ETL) 436, a third light emitting layer (EML) 434, and a third hole transport layer (HTL) 432 under the second electrode 404. can be made including Although not shown in the drawings, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 436 .

A hole injecting layer (HIL) may be further formed under the third hole transport layer (HTL) 432 .

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 434 . The third electron transport layer (ETL) 436 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the third light emitting layer (EML) 434 . The third hole transport layer (HTL) 432 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 434 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 434 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML). It is also possible to construct above or below 434. In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 134 . have. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 434, the peak wavelength of the light emitting region of the third light emitting layer (EML) 434 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

All layers such as the third electron transport layer (ETL) 436, the third light emitting layer (EML) 434, the electron injection layer (EIL), and the hole blocking layer (HBL) may be referred to as organic layers. All organic layers positioned between the second electrode 404 and the third light emitting layer (EML) 434 and the third light emitting layer (EML) 434 may be referred to as organic layers. Accordingly, all organic layers positioned between the second electrode 404 and the third light emitting layer (EML) 434 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 436, regardless of the number or thickness of the third light emitting layer (EML) 434, or regardless of the number or thickness of the electron injection layer (EIL), Alternatively, regardless of the number or thickness of hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 404 and the third light emitting layer (EML) 434, the third light emitting layer ( The light emitting position L1 of the EML) 434 is set to be positioned within a range of 250 Å to 800 Å from the second electrode 404 . Alternatively, the light emitting position L1 of the third light emitting layer (EML) 434 is set to be located within a range of 250 Å to 800 Å from the reflective surface of the second electrode 404 .

Therefore, regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layer, and the thickness of the third light emitting layer, the light emitting position L1 of the third light emitting layer (EML) 434 ) may be set to be located within a range of 250 Å to 800 Å from the second electrode 404 . Alternatively, the light emitting position L1 of the third light emitting layer (EML) 434 regardless of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third light emitting layer, and the thickness of the third light emitting layer. ) may be set to be positioned within a range of 250 Å to 800 Å from the reflective surface of the second electrode 404 .

The second light emitting part 420 may include a second hole transport layer (HTL) 422 , a second light emitting layer (EML) 424 , and a second electron transport layer (ETL) 426 .

A hole injection layer (HIL) may be further formed below the second hole transport layer (HTL) 4122).

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 424 . The second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the second light emitting layer (EML) 424 . The second hole transport layer (HTL) 422 and the electron blocking layer (EBL) may be configured as one layer.

The second light emitting layer (EML) 424 is composed of a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the second light emitting layer (EML) 424 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the first light emitting layer (EML) ( 114) is also possible. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer may be formed identically or differently above and below the second light emitting layer (EML) 424 . can The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the second light emitting layer (EML) 424, the peak wavelength of the light emitting region of the second light emitting layer (EML) 424 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 450 may be further formed between the second light emitting part 420 and the third light emitting part 430 . The second charge generation layer (CGL) 450 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The second light emitting layer (EML) 424, the second electron transport layer (ETL) 426, the second charge generating layer (CGL) 450, the third hole transport layer (HTL) 432, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 434 and the second light emitting layer (EML) 424 and the second light emitting layer (EML) 424 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 334 and the second light emitting layer (EML) 324 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layer (HTL) 432, regardless of the number or thickness of the second electron transport layer (ETL) 426, or the second charge generation layer (CGL) 450 Regardless of the number or thickness of HBL, regardless of the number or thickness of hole blocking layers (HBL), regardless of the number or thickness of electron blocking layers (EBL), or regardless of the number or thickness of hole injection layers (HIL), or Regardless of the number or thickness of the third light emitting layer (EML) 434, regardless of the number or thickness of the second light emitting layer (EML) 424, or the second electrode 404 and the third light emitting layer (EML) ) 434, regardless of the number or thickness of all organic layers, or regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 424 and the third light emitting layer (EML) 434, The light emitting position L2 of the second light emitting layer (EML) 424 may be set to be positioned within a range of 1,450 Å to 1,950 Å from the second electrode 404 . Alternatively, the light emitting position L2 of the second light emitting layer (EML) 424 may be set to be positioned within a range of 1,450 Å to 1,950 Å from the reflective surface of the second electrode 404 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the position L2 of the second light emitting layer (EML) 424 from the second electrode 404 may be set to be positioned within a range of 1,450 Å to 1,950 Å. . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the third light emitting layer, the thickness of the third light emitting layer, the second Regardless of the number of light emitting layers and the thickness of the second light emitting layer, the position L2 of the second light emitting layer (EML) 424 from the reflective surface of the second electrode 404 is located within the range of 1,450 Å to 1,950 Å. can be set

The first light emitting part 410 includes a first hole transport layer (HTL) 412, a first light emitting layer (EML) 414, and a first electron transport layer (ETL) 416 on the first electrode 402. It can be done by

Although not shown in the drawing, a hole injection layer (HIL) may be additionally formed on the first electrode 402 .

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 414 . The first electron transport layer (ETL) 416 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 414 . The first hole transport layer (HTL) 412 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 414 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm.

And, the first light emitting layer (EML) 414 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( It is also possible to configure above or below the EML) (414). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( EML) above and below 414 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the first emission layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 may be composed of two layers of a red light emitting layer and a yellow-green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the first light emitting layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The first light emitting layer (EML) 414 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the first light emitting layer (EML) 414 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 440 may be further formed between the first light emitting part 410 and the second light emitting part 420 . The first charge generating layer (CGL) 440 may include an N-type charge generating layer (N-CGL) and a P-type charge generating layer (P-CGL).

The first light emitting layer (EML) 414, the first electron transport layer (ETL) 416, the first charge generation layer (CGL) 440, the second hole transport layer 422, the hole blocking layer (HBL) ), an electron blocking layer (EBL), a hole injection layer (HIL), and the like can be referred to as organic layers. All organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424 and the first light emitting layer (EML) 414 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 416, or the second

Regardless of the number or thickness of hole transport layers (HTL) 422, regardless of the number or thickness of the first charge generation layer (CGL) 440, or regardless of the number or thickness of hole blocking layers (HBL), or Regardless of the number or thickness of electron blocking layers (EBL), regardless of the number or thickness of hole injection layers (HIL), regardless of the number or thickness of the third light emitting layer (EML) 434, or the second light emitting layer Regardless of the number or thickness of the (EML) 424, regardless of the number or thickness of the first light emitting layer (EML) 414, or the second electrode 404 and the third light emitting layer (EML) 434 Regardless of the number or thickness of all organic layers interposed therebetween, regardless of the number or thickness of all organic layers interposed between the second light emitting layer (EML) 424 and the third light emitting layer (EML) 434, or the first Regardless of the number or thickness of all organic layers between the light emitting layer (EML) 414 and the second light emitting layer (EML) 424, the light emitting position L3 of the first light emitting layer (EML) 414 is the second light emitting layer (EML) 414. It is set to be positioned within the range of 2,050 Å to 2,600 Å from the electrode 404 . Alternatively, the light emitting position L3 of the first light emitting layer (EML) 414 is set to be positioned within a range of 2,050 Å to 2,600 Å from the reflective surface of the second electrode 404 .

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, the second electrode 404 The position L3 of the first light emitting layer (EML) 414 may be set to be positioned within a range of 2,050 Å to 2,600 Å. Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, and the third organic layer. Regardless of the number of light emitting layers, the thickness of the third light emitting layer, the number of the second light emitting layers, the thickness of the second light emitting layer, the number of the first light emitting layer, and the thickness of the first light emitting layer, half of the second electrode 404 The position L3 of the first light emitting layer (EML) 414 from the slope may be set to be positioned within a range of 2,050 Å to 2,600 Å.

All layers such as the first hole transport layer (HTL) 412, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the substrate 401 and the first light emitting layer (EML) 414 and the first electrode 402 may be referred to as organic layers. Accordingly, all organic layers between the substrate 301 and the first light emitting layer (EML) 414 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 412, or regardless of the number or thickness of the first electrodes 402, or regardless of the number or thickness of the electron blocking layers (EBL), or hole injection Regardless of the number or thickness of the layers HIL, regardless of the number or thickness of the third light emitting layer (EML) 434, regardless of the number or thickness of the second light emitting layer (EML) 424, or regardless of the number or thickness of the second light emitting layer (EML) 424, or Regardless of the number or thickness of one light emitting layer (EML) 414, regardless of the number or thickness of all organic layers between the second electrode 404 and the third light emitting layer (EML) 434, or the second electrode 404 and the third light emitting layer (EML) 434 Regardless of the number or thickness of all organic layers between the light emitting layer (EML) 424 and the third light emitting layer (EML) 434, or the first light emitting layer (EML) 414 and the second light emitting layer (EML) ( 424), regardless of the number or thickness of all organic layers between the substrate 401 and the first light emitting layer (EML) 414, regardless of the number or thickness of all organic layers, the second electrode 404 The position L0 of the first electrode 402 may be set to be positioned within a range of 3,500 Å to 4,500 Å. Alternatively, the position L0 of the first electrode 402 from the reflective surface of the second electrode 404 may be set to be positioned within a range of 3,500 Å to 4,500 Å.

Accordingly, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, the first The number of organic layers, the thickness of the first organic layer, the number of the third light-emitting layers, the thickness of the third light-emitting layer, the number of the second light-emitting layers, the thickness of the second light-emitting layer, the number of the first light-emitting layers, the first light-emitting layer The position L0 of the first electrode 402 from the second electrode 404 may be set to be positioned within a range of 3,500 Å to 4,500 Å, regardless of the thickness of . Alternatively, at least one of the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the third organic layer, the thickness of the third organic layer, the number of the second organic layer, the thickness of the second organic layer, the first The number of organic layers, the thickness of the first organic layer, the number of the third light-emitting layers, the thickness of the third light-emitting layer, the number of the second light-emitting layers, the thickness of the second light-emitting layer, the number of the first light-emitting layers, the first light-emitting layer Regardless of the thickness of , the position L0 of the first electrode 402 from the reflective surface of the second electrode 404 may be set to be located within a range of 3,500 Å to 4,500 Å.

The structure shown in FIG. 35 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the white organic light emitting device, but is not limited thereto.

36 is a view showing a light emitting position of an organic light emitting device according to a tenth embodiment of the present invention.

In FIG. 36, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the second electrode 404, which can be referred to as a contour map. Here, except for the first electrode 402 and the second electrode 404, emission positions of the emission layers at the emission peak when the EPEL structure of the present invention is applied are shown. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the third light emitting layer (EML) 434 constituting the third light emitting part 430 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 434 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 434 in the range of 250 Å to 800 Å, the emission peak 434E of the third light emitting layer (EML) 434 is between 440 nm and 480 nm. put it in place For this reason, the third light emitting layer (EML) 434 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 434 constituting the third light emitting part 430. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 434 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 434 must emit light at 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 36 , the third light emitting layer (EML) 434 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 434 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 434 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the second light emitting layer (EML) 424 constituting the second light emitting part 420 is a blue light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 424 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 424 in the range of 1,450 Å to 1,950 Å, the emission peak 424E of the second light emitting layer (EML) 424 is 440 nm to 480 nm. positioned at nm. Due to this, the maximum efficiency can be achieved by emitting light in the range of 440 nm to 480 nm from the second light emitting layer (EML) 44 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the second light emitting layer (EML) 424 constituting the second light emitting part 420. In this case, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 424 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 424 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 36 , the second light emitting layer (EML) 424 does not include an auxiliary light emitting layer, and the second light emitting layer (EML) 424 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 424 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the first light emitting layer (EML) 414 constituting the first light emitting part 410 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the first light emitting layer (EML) 414 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 414 is set in the range of 2,050 Å to 2,600 Å so that the emission peak 414E is located at 510 nm to 580 nm. Due to this, maximum efficiency can be achieved by emitting light in the range of 510 nm to 580 nm from the first light emitting layer (EML) 414 .

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 410 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 414 must emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 410 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 414 must emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 410 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the first light emitting layer (EML) 414 is 540 nm to 650 nm.

Therefore, as the first light emitting layer (EML) 414, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light is emitted in the light emitting region of 510 nm to 650 nm of the first light emitting layer (EML) 414 .

In FIG. 36 , an auxiliary light emitting layer is not included in the first light emitting layer (EML) 414, and a yellow-green light emitting layer of the first light emitting layer (EML) 414 is taken as an example, and the light emitting position is shown. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 414 may have maximum efficiency in the range of 510 nm to 580 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 530 nm to 570 nm, the maximum emission range of the second emission layer is 440 nm to 470 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

37 is a diagram showing an EL spectrum according to a tenth embodiment of the present invention.

In FIG. 37, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 37, the embodiment (minimum position) is the part set as the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 434 is in the range of 250 Å to 800 Å from the second electrode 404, the minimum position is set to 250 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 434 is in the range of 250 Å to 800 Å from the second electrode 404, the maximum position is set to 800 Å.

Example (optimal position) is the part set as the light emitting position of the eighth embodiment of the present invention. For example, when the light emitting position L1 of the third light emitting layer (EML) 434 is in the range of 250 Å to 800 Å from the second electrode 404, the light emitting position in the embodiment is set to the range of 250 Å to 800 Å. .

As shown in FIG. 37, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, when the minimum position of the light emitting position is out of position, a comparison with the optimal position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. And, it can be seen that the emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 19 below. When the efficiency of the comparative example is 100%, the efficiency of the tenth embodiment of the present invention is shown.

Table 19 below compares the efficiencies of Comparative Examples and Examples of the present invention. Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( Yellow-Green) light emitting layer, and the third light emitting part is composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 19, when the EPEL structure of the present invention is applied compared to the comparative example, when the efficiency of the comparative example is 100%, the red efficiency is increased by about 22%, and the green, blue ( It can be seen that Blue) and White efficiencies are almost similar to those of Comparative Example.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 20 below.

Table 20 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimum position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 20, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the tenth embodiment of the present invention, the organic light emitting device may be a bottom emission type organic light emitting device.

The second light emitting layer and the third light emitting layer may include light emitting layers emitting the same color.

The position of the first electrode may be set within a range of 3,500 Å to 4,500 Å from the second electrode.

A light emitting position of the third light emitting layer may be set within a range of 250 Å to 800 Å from the second electrode.

A light emitting position of the second light emitting layer may be set within a range of 1,450 Å to 1,950 Å from the second electrode.

An emission position of the first emission layer may be set within a range of 2,050 Å to 2,600 Å from the second electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

38 is a view showing a white organic light emitting device according to an 11th embodiment of the present invention.

The white organic light emitting device 400 shown in FIG. 38 includes first and second electrodes 402 and 404 and a first light emitting unit 410 and a second light emitting unit 420 between the first and second electrodes 402 and 404. and a third light emitting unit 430 . In describing the present embodiment, descriptions of components identical to or corresponding to those of the previous embodiment will be omitted. In this embodiment, the light emitting position of the light emitting layers is set from the first electrode, and the light emitting position can be set from the first electrode according to device design.

The second electrode 404 is positioned within a range of 3,500 Å to 4,500 Å from the first electrode 402 . By setting the position (L0) of the second electrode 404, emission peaks of the light emitting layers constituting the first light emitting part 410, the second light emitting part 420, and the third light emitting part 430 are obtained. It is possible to improve the efficiency of the light emitting layers by locating at a specific wavelength and emitting light of the specific wavelength. In addition, the first light emitting part, the second light emitting part, and the third light emitting part have a maximum light emitting range in light emitting regions of the first light emitting layer, the second light emitting layer, and the third light emitting layer (EPEL) (Emission Position of Emitting Layers) to have a structure. In addition, two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer include light emitting layers emitting the same color, thereby providing a white organic light emitting device capable of further improving light emitting efficiency. The light emitting layer emitting the same color may be referred to as a light emitting layer including at least one light emitting layer emitting the same color.

The first light emitting part 410 includes a first hole transport layer (HTL) 412, a first light emitting layer (EML) 414, and a first electron transport layer (ETL) 416 on the first electrode 402. It can be done by

Although not shown in the drawing, a hole injection layer (HIL) may be additionally formed on the first electrode 402 .

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 414 . Also, the first electron transport layer (ETL) 416 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the first light emitting layer (EML) 414 . Also, the first hole transport layer (HTL) 412 and the electron blocking layer (EBL) may be configured as one layer.

The first light emitting layer (EML) 414 is composed of a yellow-green light emitting layer. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm.

And, the first light emitting layer (EML) 414 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or It may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When a red light emitting layer is further formed in the yellow-green light emitting layer, efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer.

And, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( It is also possible to configure above or below the EML) (414). In addition, the yellow light emitting layer and the red light emitting layer, or the red light emitting layer and the green light emitting layer, or the yellow-green light emitting layer and the red light emitting layer are the first light emitting layer ( EML) above and below 414 may be configured identically or differently.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, the peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, peak wavelengths of the emission regions of the red emission layer and the green emission layer of the first emission layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the red light emitting layer and the green light emitting layer, color reproducibility can be improved.

In addition, the peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Accordingly, the peak wavelength of the emission regions of the yellow emission layer and the red emission layer of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be a light emitting region. When composed of two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer can be increased.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 may be composed of two layers of a red light emitting layer and a yellow-green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength of the light emitting region of the first light emitting layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be a light emitting region.

The first light emitting layer (EML) 414 is a yellow-green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer. When composed of one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof, the peak wavelength of the light emitting region of the second light emitting layer (EML) 124 is 510 nm to 650 nm. It can be in the range of nm. Here, the peak wavelength may be a light emitting region.

All layers such as the first hole transport layer (HTL) 412, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the substrate 401 and the first light emitting layer (EML) 414 and the first electrode 402 may be referred to as organic layers. Accordingly, all organic layers between the substrate 401 and the first light emitting layer (EML) 414 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 412, or regardless of the number or thickness of the first electrodes 402, or regardless of the number or thickness of the electron blocking layers (EBL), or hole injection Regardless of the number or thickness of the first light emitting layer (HIL), regardless of the number or thickness of all organic layers between the substrate 401 and the first light emitting layer (EML) 414, the first light emitting layer (EML) 414 The light emitting position L1 is set to be positioned within a range of 1,500 Å to 2,050 Å from the first electrode 402 . Alternatively, the light emitting position L1 of the first light emitting layer (EML) 414 is set to be located within a range of 1,500 Å to 2,050 Å from the interface between the substrate 401 and the first electrode 402 . Accordingly, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the position L1 of the first light emitting layer (EML) 414 from the first electrode 402 is 1,500 Å to 2,050 Å. It can be set to be located within the range of . Alternatively, regardless of the number of at least one first organic layer and the thickness of the first organic layer, the light emitting position L1 of the first light emitting layer (EML) 414 is the substrate 401 and the first electrode 402 ) can be set to be located within the range of 1,500 Å to 2,050 Å from the interface.

The second light emitting part 420 may include a second hole transport layer (HTL) 422 , a second light emitting layer (EML) 424 , and a second electron transport layer (ETL) 426 . A hole injection layer (HIL) may be further formed under the second hole transport layer (HTL) 422 . A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 424 . An electron blocking layer (EBL) may be further formed under the second light emitting layer (EML) 424 .

The second light emitting layer (EML) 424 is composed of a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the second light emitting layer (EML) 424 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the second light emitting layer (EML) ( 424) is also possible. In addition, as the auxiliary light emitting layer, a yellow-green light emitting layer, a red light emitting layer, or a green light emitting layer may be formed identically or differently above and below the second light emitting layer (EML) 424 . can The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the second light emitting layer (EML) 424, the peak wavelength of the light emitting region of the first light emitting layer (EML) 424 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A first charge generating layer (CGL) 440 may be further formed between the first light emitting part 410 and the second light emitting part 420 . The first charge generating layer 140 may include an N-type charge generating layer and a P-type charge generating layer.

The first light emitting layer (EML) 414, the first electron transport layer (ETL) 416, the first charge generating layer (CGL) 440, the second hole transport layer (HTL) 422, hole blocking All layers such as the HBL, the electron blocking layer (EBL), and the hole injection layer (HIL) may be referred to as organic layers. All organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424 and the first light emitting layer (EML) 414 may be referred to as organic layers. Accordingly, all organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layer (ETL) 416, regardless of the number or thickness of the second hole transport layer (HTL) 422, or the first charge generating layer (CGL) 440 Regardless of the number or thickness, or the number or thickness of hole blocking layers (HBL), or the number or thickness of electron blocking layers (EBL), or the number or thickness of hole injection layers (HIL), or the above Regardless of the number or thickness of the first light emitting layer (EML) 414, or regardless of the number or thickness of all organic layers between the substrate 401 and the first light emitting layer (EML) 414, or the first light emitting layer Regardless of the number or thickness of all organic layers between the (EML) 414 and the second light emitting layer (EML) 424, the light emitting position L2 of the second light emitting layer (EML) 424 is the first electrode It can be set to be located within the range of 2,150 Å to 2,600 Å from (402). Alternatively, the light emitting position L2 of the second light emitting layer (EML) 424 may be set to be located within a range of 2,150 Å to 2,600 Å from the interface between the substrate 401 and the first electrode 402.

Therefore, regardless of the number of at least one of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The light emitting position L2 of the second light emitting layer (EML) 424 may be set to be located within a range of 2,150 Å to 2,600 Å from the first electrode 402 . Alternatively, regardless of at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layers, the thickness of the second organic layer, the number of the first light emitting layers, and the thickness of the first light emitting layer, the The light emitting position L2 of the second light emitting layer (EML) 424 may be set to be located within a range of 2,150 Å to 2,600 Å from the interface between the substrate 401 and the first electrode 402 .

The third light emitting part 430 includes a third electron transport layer (ETL) 436, a third light emitting layer (EML) 434, and a third hole transport layer (HTL) 432 under the second electrode 404. can be made including

Although not shown in the drawings, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 436 .

A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 432 .

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 434 . The third electron transport layer (ETL) 436 and the hole blocking layer (HBL) may be configured as one layer.

An electron blocking layer (EBL) may be additionally formed under the third light emitting layer (EML) 434 . The third hole transport layer (HTL) 432 and the electron blocking layer (EBL) may be configured as one layer.

The third light emitting layer (EML) 434 is composed of either a blue light emitting layer or a blue light emitting layer including an auxiliary light emitting layer capable of emitting other colors. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

The auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, and a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further formed, the luminous efficiency of the green light emitting layer or the red light emitting layer may be further improved. When configuring the third light emitting layer (EML) 434 including the auxiliary light emitting layer, the yellow-green light emitting layer, the red light emitting layer, or the green light emitting layer is the third light emitting layer (EML). It is also possible to construct above or below 434. In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the third light emitting layer (EML) 434 . have. The location or number of light emitting layers can be selectively arranged according to the configuration and characteristics of the device, but is not necessarily limited thereto.

When the auxiliary light emitting layer is formed on the third light emitting layer (EML) 434, the peak wavelength of the light emitting region of the third light emitting layer (EML) 434 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be a light emitting region.

A second charge generating layer (CGL) 450 may be further formed between the second light emitting part 420 and the third light emitting part 430 . The second charge generation layer (CGL) 450 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The second light emitting layer (EML) 424, the second electron transport layer (ETL) 426, the third hole transport layer (HTL) 432, the second charge generation layer (CGL) 450, the hole injection layer (HIL), electron blocking layer (EBL), hole blocking layer (HBL) and the like can be referred to as organic layers. All organic layers between the second light emitting layer (EML) 424 and the third light emitting layer (EML) 434 and the second light emitting layer (EML) 424 may be referred to as organic layers. Accordingly, all organic layers between the second light emitting layer (EML) 424 and the third light emitting layer (EML) 434 may be referred to as a third organic layer.

Regardless of the number or thickness of the second light emitting layer (EML) 424, regardless of the number or thickness of the second electron transport layer (ETL) 426, or the number or thickness of the third hole transport layer (HTL) 432 Regardless of the number or thickness of the second charge generation layer (CGL) 450, regardless of the number or thickness of the hole injection layer (HIL), or regardless of the number or thickness of the electron blocking layer (EBL) without, or regardless of the number or thickness of the hole blocking layer (HBL), or regardless of the number or thickness of the first light emitting layer (EML) 414, or the substrate 401 and the first light emitting layer (EML) 414 ) Regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424, regardless of the number or thickness of all organic layers between the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424, or Regardless of the number or thickness of all organic layers between the second light-emitting layer (EML) 424 and the third light-emitting layer (EML) 434, the light-emitting position L3 of the third light-emitting layer (EML) 434 is the first light-emitting layer (EML) 434. It may be set to be positioned within a range of 3,300 Å to 3,850 Å from the electrode 402 . Alternatively, the light emitting position L3 of the third light emitting layer (EML) 434 may be set to be positioned within a range of 3,300 Å to 3,850 Å from the interface between the substrate 401 and the first electrode 402 .

Accordingly, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the first light emitting layer, the thickness of the first light emitting layer, the third Regardless of the number of organic layers, the thickness of the third organic layer, the number of second light-emitting layers, and the thickness of the second light-emitting layer, the light-emitting position L3 of the third light-emitting layer (EML) 434 is the first electrode 402 ) from 3,300 Å to 3,850 Å. Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the first Regardless of the number of light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, and the thickness of the second light emitting layer, the light emitting position L3 of the third light emitting layer (EML) 434 is relative to the substrate 401 It may be set to be positioned within a range of 3,300 Å to 3,850 Å from the interface of the first electrode 402 .

In addition, all layers such as the third light emitting layer (EML) 434, the third electron transport layer (ETL) 436, the hole blocking layer (HBL), and the electron injection layer (EIL) may be referred to as organic layers. All organic layers between the third light emitting layer (EML) 434 and the second electrode 404 and the third light emitting layer (EML) 434 may be referred to as organic layers. Accordingly, all organic layers between the third light emitting layer (EML) 434 and the second electrode 404 may be referred to as a first organic layer.

Regardless of the number or thickness of the third electron transport layer (ETL) 436, regardless of the number or thickness of the electron injection layer (EIL), regardless of the number or thickness of the hole blocking layer (HBL), or the third Regardless of the number or thickness of the light emitting layers (EML) 434, regardless of the number or thickness of the second light emitting layers (EML) 424, or regardless of the number or thickness of the first light emitting layer (EML) 414, Alternatively, regardless of the number or thickness of all organic layers between the substrate 401 and the first light emitting layer (EML) 414, or the first light emitting layer (EML) 414 and the second light emitting layer (EML) 424 ), regardless of the number or thickness of all organic layers between the second light emitting layer (EML) 424 and the third light emitting layer (EML) 434, regardless of the number or thickness of all organic layers, or 3 Regardless of the thickness of all organic layers between the light emitting layer (EML) 434 and the second electrode 404, the position L0 of the second electrode 404 is 3,500 Å away from the first electrode 402. to 4,500 Å. Alternatively, the position L0 of the second electrode 404 may be set to be positioned within a range of 3,500 Å to 4,500 Å from the interface between the substrate 401 and the first electrode 402 .

Thus, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, and the fourth organic layer. The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer The position L0 of the second electrode 404 may be set to be positioned within a range of 3,500 Å to 4,500 Å from the first electrode 402 regardless of the thickness of the . Alternatively, at least one of the number of the first organic layer, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, the third light emitting layer Regardless of the thickness of , the position L0 of the second electrode 404 may be set to be positioned within a range of 3,500 Å to 4,500 Å from the interface between the substrate 401 and the first electrode 402 .

Here, the light emitting position L3 of the third light emitting layer (EML) 434 may be set to be positioned within a range of 4,500 Å to 5,100 Å from the first electrode 402 . Also, the position L0 of the second electrode 404 may be set to be located within a range of 4,500 Å to 6,000 Å from the first electrode 402 . When the light emitting position L3 of the third light emitting layer (EML) 434 is set to 5,000 Å from the second electrode 403, the position L0 of the second electrode 404 is the first electrode ( 402) may be set to be positioned within a range of 4,550 Å to 6,000 Å. When the light emitting position L3 of the third light emitting layer (EML) 434 is set to 5,100 Å from the first electrode 402, the position L0 of the second electrode 404 is the first position L0 of the first electrode 402. It may be set to be positioned within a range of 5,150 Å to 6,000 Å from the electrode 402 .

Accordingly, the present invention provides at least one of the number of the first organic layers, the thickness of the first organic layer, the number of the second organic layer, the thickness of the second organic layer, the number of the third organic layer, the thickness of the third organic layer, The number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light emitting layers, the thickness of the first light emitting layer, the number of the second light emitting layer, the thickness of the second light emitting layer, the number of the third light emitting layer, Regardless of the thickness of the third light emitting layer, the position of the second electrode 404 from the first electrode 402 and the position of the light emitting layers can be set.

The structure shown in FIG. 38 represents an example of the present invention, and can be selectively configured according to the structure or characteristics of the organic light emitting device, but is not limited thereto.

39 is a view showing a light emitting position of an organic light emitting device according to an eleventh embodiment of the present invention.

In FIG. 39, the horizontal axis represents the wavelength region of light, and the vertical axis represents the light emitting positions of the light emitting layers constituting the light emitting part from the first electrode 402, which can be referred to as a contour map. Here, except for the second electrode 404, emission positions of the emission layers are shown at the emission peak when the EPEL structure of the present invention is applied. And, it shows the light emitting positions of the light emitting layers having the maximum light emitting range in the light emitting area of the light emitting layers.

Since the first light emitting layer (EML) 414 constituting the first light emitting part 410 is a yellow-green light emitting layer, the peak wavelength of the light emitting region of the first light emitting layer (EML) 414 ( peak wavelength) range may be in the range of 510 nm to 580 nm. The maximum efficiency can be achieved in the white region of the contour map only when the light is emitted in the 510 nm to 580 nm light emitting region of the yellow-green light emitting layer.

Accordingly, the emission position of the first light emitting layer (EML) 414 is set in the range of 1,500 Å to 2,050 Å so that the emission peak 414E is located at 510 nm to 580 nm. Due to this, maximum efficiency can be achieved by emitting light in the range of 510 nm to 580 nm from the first light emitting layer (EML) 414 .

Also, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 410 may be composed of two layers of a red light emitting layer and a green light emitting layer. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. A peak wavelength of a light emitting region of the green light emitting layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 414 must emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, according to the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 410 is composed of two layers of a red light emitting layer and a yellow-green light emitting layer. can do. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. The peak wavelength of the light emitting region of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the light emitting region of the first light emitting layer (EML) 414 must emit light in the range of 510 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In addition, depending on the characteristics or structure of the device, the first light emitting layer (EML) 414 of the first light emitting part 310 may be composed of two layers, a yellow light emitting layer and a red light emitting layer. The peak wavelength of the light emitting region of the yellow light emitting layer may be in the range of 540 nm to 580 nm. The peak wavelength of the light emitting region of the red light emitting layer may be in the range of 600 nm to 650 nm. Therefore, in this case, maximum efficiency can be obtained in the white region of the contour map only when the light emitting region of the first light emitting layer (EML) 414 is 540 nm to 650 nm.

Therefore, as the first light emitting layer (EML) 414, a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, or a red light emitting layer and a green light emitting layer, or When composed of one or a combination of a yellow-green light emitting layer and a red light emitting layer, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 314 is 510 nm to 650 nm. In this case, the maximum efficiency can be obtained in the white region of the contour map only when the light is emitted in the light emitting region of 510 nm to 650 nm of the first light emitting layer (EML) 414 .

In FIG. 39 , an auxiliary light emitting layer is not included in the first light emitting layer (EML) 414, and a yellow-green light emitting layer of the first light emitting layer (EML) 414 is taken as an example, and the light emitting position is shown. Accordingly, the peak wavelength range of the light emitting region of the first light emitting layer (EML) 414 may produce maximum efficiency in the range of 510 nm to 580 nm.

Since the second light emitting layer (EML) 424 constituting the second light emitting part 420 is a blue light emitting layer, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 424 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the second light emitting layer (EML) 424 in the range of 2,150 Å to 2,600 Å, the emission peak 424E of the second light emitting layer (EML) 424 is 440 nm to 480 nm. positioned at nm. Due to this, the maximum efficiency can be achieved by emitting light in the range of 440 nm to 480 nm from the second light emitting layer (EML) 44 .

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the second light emitting layer (EML) 424 constituting the second light emitting part 420. In this case, the peak wavelength range of the light emitting region of the second light emitting layer (EML) 424 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the second light emitting layer (EML) 424 should emit light between 440 nm and 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 39 , the second light emitting layer (EML) 424 does not include an auxiliary light emitting layer, and the second light emitting layer (EML) 424 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the second light emitting layer (EML) 424 may have maximum efficiency in the range of 440 nm to 480 nm.

Since the third light emitting layer (EML) 434 constituting the third light emitting part 430 is a blue light emitting layer, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 434 may range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white area of the contour map only when the light is emitted in the light emitting range of 440 nm to 480 nm of the blue light emitting layer.

Therefore, by setting the emission position of the third light emitting layer (EML) 434 in the range of 3,300 Å to 3,850 Å, the emission peak 434E of the third light emitting layer (EML) 434 is 440 nm to 480 nm. positioned at nm. For this reason, the third light emitting layer (EML) 434 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, and a sky blue light emitting layer.

In addition, a yellow-green or red light emitting layer or a green light emitting layer may be configured as an auxiliary light emitting layer in the third light emitting layer (EML) 434 constituting the third light emitting part 430. In this case, the peak wavelength range of the light emitting region of the third light emitting layer (EML) 434 may be in the range of 440 nm to 650 nm. Therefore, in this case, the light emitting region of the third light emitting layer (EML) 434 must emit light at 440 nm to 650 nm to achieve maximum efficiency in the white region of the contour map.

In FIG. 39 , the third light emitting layer (EML) 434 does not include an auxiliary light emitting layer, and the third light emitting layer (EML) 434 takes a blue light emitting layer as an example and shows the light emitting position. Accordingly, the peak wavelength of the light emitting region of the third light emitting layer (EML) 434 may have maximum efficiency in the range of 440 nm to 480 nm.

As described above, the position of the emitting peak changes according to the position of the light emitting layer. The present invention applies an Emission Position of Emitting Layers (EPEL) structure in which the emission peak of the emission layer is located in a desired emission region by setting the emission position of the emission layer constituting the emission unit.

Therefore, by applying an Emission Position of Emitting Layers (EPEL) structure to the light emitting layer, the emitting peak is located at a specific wavelength, and thus the light emitting layers can achieve maximum efficiency in light corresponding to a specific wavelength.

Further, a light emitting range in which the light emitting layers can achieve maximum efficiency in the light emitting region of the specific wavelength may be referred to as a maximum light emitting range. That is, the peak wavelength may be an emission region. Accordingly, the maximum emission range of the first emission layer is 530 nm to 570 nm, the maximum emission range of the second emission layer is 440 nm to 470 nm, and the maximum emission range of the third emission layer is It may be 440 nm to 470 nm.

That is, light must be emitted in the maximum emission range of 440 nm to 470 nm of the blue light emitting layer and the maximum emission range of 530 nm to 570 nm of the yellow-green light emitting layer. The maximum efficiency can be obtained in the white area. It can be seen that the light-emitting layer of the present invention can achieve maximum efficiency by setting the light-emitting position of the light-emitting layer of the present invention to correspond to the light-emitting region. In addition, the EPEL structure of the present invention includes at least one number of first organic layers, a thickness of the first organic layer, a number of second organic layers, a thickness of the second organic layer, a number of the third organic layers, and a thickness of the third organic layer. thickness, the number of the fourth organic layer, the thickness of the fourth organic layer, the number of the first light-emitting layers, the thickness of the first light-emitting layer, the number of the second light-emitting layer, the thickness of the second light-emitting layer, the number of the third light-emitting layer , Regardless of the thickness of the third light emitting layer, it can be seen that the light emitting layer can achieve maximum efficiency by configuring the first light emitting layer, the second light emitting layer, and the third light emitting layer to have a maximum light emitting range.

40 is a diagram showing an EL spectrum according to an 11th embodiment of the present invention.

In FIG. 40, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 40, the embodiment (minimum position) is a part set to the minimum position when the emission positions of the light emitting layers are set. For example, when the light emitting position L1 of the first light emitting layer (EML) 414 is in the range of 1,500 Å to 2,050 Å from the first electrode 402, the minimum position is set to 1,500 Å.

The embodiment (maximum position) is a part set to the maximum position when the emission positions of the light emitting layers are set. When the light emitting position L1 of the first light emitting layer (EML) 414 is in the range of 1,500 Å to 2,050 Å from the first electrode 402, the maximum position is set to 2,050 Å.

Example (optimal position) is the part set as the light emitting position of the eighth embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 414 is in the range of 1,500 Å to 2,050 Å from the first electrode 402, the light emitting position in the embodiment is in the range of 1,500 Å to 2,050 Å. is set to

As shown in FIG. 40, when the minimum position of the light emitting position is out of the EPEL (Emission Position of Emitting Layers) structure of the present invention, a comparison with the optimal position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. In addition, the luminescence intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light, and is outside the peak wavelength range of yellow-green light. Able to know. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 600 nm to 650 nm of red light.

In addition, in the Emission Position of Emitting Layers (EPEL) structure of the present invention, a comparison with the optimal position when the light emitting position deviate from the maximum position is as follows. It can be seen that the emission intensity decreases in the peak wavelength range of 440 nm to 480 nm of blue light. In addition, it can be seen that the emission intensity significantly decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light.

Therefore, it can be seen that the luminous intensity increases in the peak wavelength range of blue light when set to the optimal position of the present invention than when set to the minimum position or maximum position of the embodiment. In addition, it can be seen that the luminous intensity increases in the peak wavelength range of yellow-green light when the optimum position of the present invention is set than when the minimum position or maximum position of the embodiment is set. Alternatively, it can be seen that the luminescence intensity increases in the peak wavelength range of red light when set to the optimal position of the present invention than when set to the maximum position.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 21 below. When the efficiency of the comparative example is 100%, the efficiency of the eleventh embodiment of the present invention is shown.

Table 21 below compares the efficiencies of Comparative Examples and Examples of the present invention. Comparative Example is a bottom emission type white organic light emitting device including a first light emitting part, a second light emitting part, and a third light emitting part. The first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( Yellow-Green) light emitting layer, and the third light emitting part is composed of a blue light emitting layer. An embodiment is a white organic light emitting device of a top emission method when an optimum position of an emission position of emitting layers (EPEL) structure of the present invention is applied.

As shown in Table 21, when the EPEL structure of the present invention was applied compared to the comparative example, when the efficiency of the comparative example was 100%, the red efficiency increased by about 22%, and the green, blue ( It can be seen that Blue) and White efficiencies are almost similar to those of Comparative Example.

The panel efficiencies of the white organic light emitting device to which the Emission Position of Emitting Layers (EPEL) structure of the present invention is applied and the comparative example are shown in Table 22 below.

Table 22 below shows the efficiency of the embodiment (minimum position) and the embodiment (maximum position) when the efficiency of the embodiment (optimal position) is 100%.

The panel efficiency was measured when the driving current density was 10 mA/cm ² . And, when the panel efficiency of the embodiment is 100%, the panel efficiency of the embodiment (minimum position) and the embodiment (maximum position) are measured.

As shown in Table 22, it can be seen that the efficiency of red, green, blue, and white is reduced at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is more reduced than in the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the emission position of the Emission Position of Emitting Layers (EPEL) structure of the present invention deviates from the optimal position.

As described in the eleventh embodiment of the present invention, the organic light emitting device may be a bottom emission type organic light emitting device.

The location of the second electrode may be set within a range of 3,500 Å to 4,500 Å from the first electrode.

A light emitting position of the first light emitting layer may be set within a range of 1,500 Å to 2,050 Å from the first electrode.

A light emitting position of the second light emitting layer may be set within a range of 2,150 Å to 2,600 Å from the first electrode.

A light emitting position of the third light emitting layer may be set within a range of 3,300 Å to 3,850 Å from the first electrode.

The first light emitting layer may include one or a combination of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer.

The second light emitting layer and the third light emitting layer may include one or a combination of a blue light emitting layer, a blue light emitting layer and a yellow-green light emitting layer, a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer.

The light emitting area of the first light emitting layer may be in the range of 510 nm to 650 nm, the light emitting area of the second light emitting layer may be in the range of 440 nm to 650 nm, and the light emitting area of the third light emitting layer may be in the range of 440 nm to 650 nm.

The maximum emission range of the first emission layer is in the range of 530 nm to 570 nm, the maximum emission range of the second emission layer is in the range of 440 nm to 470 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. can

As described above, it can be seen that the emission intensity of the light emitting layer can be increased when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied. In addition, it can be seen that the panel efficiency is improved because the light emission intensity is increased.

41 is a cross-sectional view of an organic light emitting display device including an organic light emitting device according to an embodiment of the present invention, which uses the organic light emitting devices according to the tenth and eleventh embodiments of the present invention described above. In describing the present embodiment, descriptions of elements identical to or corresponding to those of the previous embodiment will be omitted.

As shown in FIG. 41, an organic light emitting display device 4000 according to the present invention includes a substrate 40, a thin film transistor (TFT), an overcoat layer 4150, a first electrode 402, a light emitting unit 4180, and and a second electrode (104). The thin film transistor (TFT) includes a gate electrode 4115, a gate insulating layer 4120, a semiconductor layer 4131, a source electrode 4133 and a drain electrode 4135.

In FIG. 41, the thin film transistor (TFT) is shown as an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 40 may be made of glass, metal, or plastic.

A gate electrode 4115 is formed over the substrate 40 . A gate insulating layer 4120 is formed over the gate electrode 4115 .

A semiconductor layer 4131 is formed over the gate insulating layer 4120 .

The source electrode 4133 and the drain electrode 4135 may be formed on the semiconductor layer 4131 .

A protective layer 4140 is formed on the source electrode 4133 and the drain electrode 4135 .

A color filter 4145 is formed on the first protective layer 4140 .

An overcoat layer 4150 is formed on the color filter 4145.

A first electrode 402 is formed on the overcoating layer 4150 . The first electrode 402 is electrically connected to the drain electrode 4135 through a contact hole CH in a predetermined area of the protective layer 4140 and the overcoating layer 4150 . 41 shows that the drain electrode 4135 and the first electrode 4102 are electrically connected, but the source electrode ( 4133) and the first electrode 402 may be electrically connected.

A bank layer 4170 is formed on the first electrode 402 and defines a pixel area.

The light emitting part 4180 is formed on the bank layer 4170 . As shown in the tenth and eleventh embodiments of the present invention, the light emitting part 4180 includes the first light emitting part 410 formed on the first electrode 402, the second light emitting part 420 and It consists of a third light emitting part (430).

The second electrode 404 is formed on the light emitting part 4180 .

Although not shown in FIG. 41 , an encapsulation portion may be formed on the second electrode 404 . The sealing part serves to prevent moisture from penetrating into the light emitting part 4180 . The encapsulation substrate may be made of glass, plastic, or metal.

Although the embodiments of the present invention have been described in more detail with reference to the accompanying drawings, the present invention is not necessarily limited to these embodiments, and may be variously modified and implemented without departing from the technical spirit of the present invention. . Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be construed according to the scope of the claims, and all technical ideas within the scope equivalent thereto should be construed as being included in the scope of the present invention.

100, 200, 300, 400: white organic light emitting device
102, 202, 302, 402: first electrode
104, 204, 304, 404: second electrode
110, 210, 310, 410: first light emitting unit
120, 220, 320, 420: second light emitting unit
130, 230, 330, 430: third light emitting unit
114, 214, 314, 414: first light emitting layer
124, 224, 324, 424: second light emitting layer
134, 234, 334, 434: third light emitting layer

Claims (10)

a first light emitting unit including a first light emitting layer and disposed between the first electrode and the second electrode;
a second light emitting unit including a second light emitting layer and disposed above the first light emitting unit; and
It includes a third light emitting layer, and includes a third light emitting part over the second light emitting part,
The first light emitting part, the second light emitting part, and the third light emitting part are of a top emission type,
Two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer emit light of the same color,
The first light emitting layer is positioned in a range of 1,500 Å to 2,050 Å from the first electrode, a white organic light emitting device. According to claim 1,
The second electrode is positioned in a range of 3,500 Å to 4,500 Å from the first electrode, the white organic light emitting device. According to claim 1,
The third light emitting layer is positioned in a range of 3,300 Å to 3,850 Å from the first electrode, a white organic light emitting device. a first light emitting unit including a first light emitting layer and disposed between the first electrode and the second electrode;
a second light emitting unit including a second light emitting layer and disposed above the first light emitting unit; and
It includes a third light emitting layer, and includes a third light emitting part over the second light emitting part,
The first light emitting part, the second light emitting part, and the third light emitting part are of a top emission type,
Two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer emit light of the same color,
The second electrode is positioned in a range of 3,500 Å to 4,500 Å from the first electrode, the white organic light emitting device. According to claim 4,
The third light emitting layer is positioned in a range of 3,300 Å to 3,850 Å from the first electrode, a white organic light emitting device. a first light emitting unit including a first light emitting layer and disposed between the first electrode and the second electrode;
a second light emitting unit including a second light emitting layer and disposed above the first light emitting unit; and
It includes a third light emitting layer, and includes a third light emitting part over the second light emitting part,
The first light emitting part, the second light emitting part, and the third light emitting part are of a top emission type,
Two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer emit light of the same color,
The third light emitting layer is positioned in a range of 3,300 Å to 3,850 Å from the first electrode, a white organic light emitting device. According to any one of claims 1 to 6,
The two light emitting units including the two light emitting layers emitting light of the same color are disposed adjacent to each other. According to any one of claims 1 to 6,
The two light emitting layers emitting the same color are either a blue light emitting layer, or a blue light emitting layer and a yellow-green light emitting layer, or a blue light emitting layer and a red light emitting layer, or a blue light emitting layer and a green light emitting layer, or a combination thereof. A white organic light emitting device. According to any one of claims 1 to 6,
The other light emitting layer other than the two light emitting layers emitting the same color is one of a yellow-green light emitting layer, a yellow light emitting layer and a red light emitting layer, a red light emitting layer and a green light emitting layer, or a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. Consisting of, a white organic light emitting device. According to any one of claims 1 to 6,
a first charge generation layer between the first light emitting part and the second light emitting part; and
Further comprising a second charge generation layer between the second light emitting part and the third light emitting part, the white organic light emitting device.

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