KR102151412B1 - 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 includes a first light-emitting unit disposed between a first electrode and a second electrode, including a first light-emitting layer, and a second light-emitting unit disposed on the first light-emitting unit and including a second light-emitting layer. A light-emitting part and a third light-emitting part disposed on the second light-emitting part and including a third light-emitting layer are disposed. According to an exemplary embodiment of the present invention, the first emission layer, the second emission layer, and the third emission layer corresponding to the emission area of the first emission layer, the second emission layer, and the third emission layer have a maximum emission range. It features an EPEL (Emission Position of Emitting Layers) structure.

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.

As the information age enters, the field of display that visually expresses electrical information signals has rapidly developed, and in response to this, various flat display devices with excellent performance of thinner, lighter, and low power consumption. Device) is being developed.

Specific examples of such a flat panel display 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) and the like.

In particular, the organic light-emitting display device is a self-luminous device, and has an advantage in that the response speed is faster and the luminous efficiency, luminance, and viewing angle are greater than other flat panel display devices.

In the organic light-emitting display device, an organic emission layer is formed between two electrodes. Electrons and holes are respectively injected from the two electrodes into the organic emission layer to generate excitons according to the combination of electrons and holes. In addition, it is a device using the principle that light is generated 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 fluorescent material to implement white color. However, a light emitting layer made of a fluorescent material has a theoretical quantum efficiency of about 25% compared to a light emitting layer made of a phosphorescent material. For this reason, there is a problem that the blue light emitting layer made of a fluorescent material does not produce sufficient luminance compared to the 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 lifespan performance due to the material and light-emitting structure of the organic light-emitting layer, and various methods to improve light-emitting efficiency and life 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 device can be manufactured by using a single material or by doping two or more materials. For example, there is a method in which red and green dopants are used for a blue host or red, green, and blue dopants are added to a host material having a large band gap energy. However, this method has a problem in that energy transfer to the dopant is incomplete and it is difficult to adjust the white balance.

In addition, due to the characteristics of the dopant itself, there is a limit to the component of the dopant included in the light emitting layer. In addition, since the focus is on the realization of white light when each emission layer is mixed, the wavelength characteristics having an emitting peak value at a wavelength other than red, green, and blue are displayed. do. Therefore, when the color filter is included, there is a problem that the color reproduction rate is deteriorated. In addition, the lifespan of the dopant material is different, so that a color shift occurs during continuous use.

Alternatively, two light emitting layers having a complementary color relationship may be stacked to emit white light. However, in this structure, when white light passes through the color filter, there is a difference between the peak wavelength region of each light-emitting layer and the transmission region of the color filter. Accordingly, a color range that can be expressed is narrowed, and thus, there may be difficulties in implementing a desired color reproduction rate.

For example, when a blue emission layer and a yellow emission layer are stacked, white light is emitted while peak wavelengths are formed in the blue and yellow wavelength regions. When the white light passes through the red, green, and blue color filters, respectively, the transmittance of the blue wavelength region decreases compared to the red or green wavelength region, resulting in lower luminous efficiency and color reproduction.

In addition, the luminous efficiency of the yellow phosphorescent light emitting layer is relatively higher than that of the blue fluorescent light emitting layer, thereby reducing the panel efficiency and color reproducibility due to the difference in efficiency between the phosphorescent light emitting layer and the fluorescent light emitting layer. 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 emission layer and a green-red phosphorescent emission layer are stacked, there is a problem that the luminance of blue is relatively lower than that of green-red.

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

In addition, the thickness of the emission layers, the number of emission layers, the thickness of the organic layers, or the number of organic layers may be adjusted in order to improve the emission efficiency of the emission layers at a desired emission peak. However, when the light emitting layers or organic layers are formed thick, an increase in the process and a decrease in lifespan are involved, and thus it is difficult to apply them to a large area organic light emitting display device.

Accordingly, the inventors of the present invention recognized the above-mentioned problems and conducted several experiments to improve luminous efficiency by allowing the light-emitting layers to emit light in a desired light-emitting region, regardless of the thickness or number of the light-emitting layers, or the thickness or number of organic layers. Was done.

As described above, in order to improve the luminous efficiency, two or more light-emitting layers may be formed to achieve a desired white color. However, since this increases the thickness of the device, there is a problem that the driving voltage of the device increases. In addition, although the organic layers constituting the light emitting part may be formed 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 since the number or thickness of the organic layers affects the luminous efficiency or the luminous intensity of the emission layer. Accordingly, it has been recognized that it is very difficult to construct a device capable of implementing a desired white color by configuring an organic layer having a desired number or thickness with a desired characteristic without increasing the thickness of the device.

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 order to improve the efficiency of the blue light-emitting layer through several experiments, and an additional light-emitting layer is laminated. In addition, in this structure, a white organic light-emitting device of a lower emission type having a new structure in which the light-emitting efficiency of the light-emitting layer and the panel efficiency can be improved was invented.

In addition, the inventors of the present invention invented a new top-emitting type white organic light-emitting device having a new structure in which luminous efficiency and panel efficiency of the light-emitting layer can be improved through various experiments, and since no polarizing plate is used.

A 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 layers 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 to provide a white organic light emitting device of a bottom emission method capable of improving luminous efficiency and panel efficiency.

In addition, the 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 the emission position is set to the emission layer, thereby improving luminous efficiency, panel efficiency, and luminance. It is to provide a light emitting device.

In addition, a 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 emission layers, and the thickness of the emission layer. Is to provide.

The white organic light-emitting device according to the present invention includes a first light-emitting unit disposed between a first electrode and a second electrode, including a first light-emitting layer, and a second light-emitting unit disposed on the first light-emitting unit and including a second light-emitting layer. A light-emitting part and a third light-emitting part disposed on the second light-emitting part and including a third light-emitting layer are disposed. According to an embodiment of the present invention, the first light emitting part, the second light emitting part, and the third light emitting part include the first light emitting layer corresponding to the light emitting area of the first light emitting layer, the second light emitting layer, and the third light emitting layer, and the A white organic light-emitting device capable of improving luminous efficiency and panel efficiency of an emission layer by having an Emission Position of Emitting Layers (EPEL) structure having a maximum emission range in the emission region of the second emission layer and the third emission layer is provided.

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

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

The emission position of the third emission layer may be set in the range of 200 Å to 800 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 1,800 Å to 2,550 Å from the second electrode.

The emission position of the first emission layer may be set in a range of 2,650 Å to 3,300 Å from the second electrode.

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

The emission position of the first emission layer may be set in the range of 2,000 Å to 2,650 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 2,750 Å to 3,500 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 4,500 Å to 5,100 Å from the first electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

The second emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the third emission layer may be set in a range of 250 Å to 800 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 1,450 Å to 1,950 Å from the second electrode.

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

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

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

The emission position of the first emission layer may be set in the range of 1,500 Å to 2,050 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 2,150 Å to 2,600 Å from the first electrode.

The emission position of the third emission layer may be set in 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 in a range of 4,700 Å to 5,400 Å from the first electrode.

The emission position of the first emission layer may be set in the range of 150 Å to 700 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 1,600 Å to 2,300 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 2,400 Å to 3,100 Å from the first electrode.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

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

The emission position of the third emission layer may be set in a range of 2,050 Å to 2,750 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 2,850 Å to 3,550 Å from the second electrode.

The emission position of the third emission layer may be set in the range of 4,450 Å to 5,000 Å from the first electrode.

The second emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the first emission layer may be set in a range of 200 Å to 700 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 1,200 Å to 1,800 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 2,400 Å to 3,100 Å from the first electrode.

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

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

The emission position of the third emission layer may be set in a range of 2,050 Å to 2,750 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 3,350 Å to 3,950 Å from the second electrode.

The emission position of the first emission layer may be set in 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 emission layer on a substrate, a second organic layer and a second emission layer on the first emission layer, and a third organic layer and a third emission layer on the second emission layer. The first emission layer comprising an emission layer and a fourth organic layer on the third emission layer, regardless of the thickness of at least one first organic layer, the thickness of the second organic layer, the thickness of the third organic layer, and the thickness of the fourth organic layer, The second emission layer and the third emission layer have an Emission Position of Emitting Layers (EPEL) structure having a maximum emission range in the emission regions of the first emission layer, the second emission layer, and the third emission layer, so that the emission efficiency of the emission layer And it provides a white organic light emitting device capable of improving the panel efficiency.

In the EPEL structure, the first emission layer, the second emission layer and the third emission layer emit maximum light 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. It can be configured to have a range.

The EPEL structure is configured such that the first emission layer, the second emission layer, and the third emission layer have a maximum emission range regardless of the thickness of the at least one first emission layer, the second emission layer, and the third emission layer. I can.

The EPEL structure is configured such that the first emission layer, the second emission layer, and the third emission layer have a maximum emission range regardless of the number of at least one first emission layer, the number of second emission layers, and the number of third emission layers. I can.

Details of other embodiments 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 emission layer corresponding to the emission region is set to the emission layer according to an exemplary embodiment of the present invention, there is an effect of improving the emission efficiency of the emission layer.

In addition, since the emission intensity of the emission layer is increased, there is an effect of improving panel efficiency and device life.

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

By applying the EPEL (Emission Position of Emission Layers) structure regardless of the thickness of the device, it is possible to configure an organic light emitting device suitable for the device structure or characteristics, thus optimizing device efficiency.

In addition, since there is no need to use a polarizer, there is an effect of providing an organic light emitting display device with improved aperture ratio and brightness.

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

Since the contents of the invention described in the problems to be solved above, the means for solving the problems, and the effects do not specify essential features of the claims, the scope of the claims is not limited by the matters described in the contents of the invention.

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

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms different from each other, and only these embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the 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 exemplary, and the present invention is not limited to the illustrated matters. The same reference numerals refer to the same components throughout the specification. In addition, in describing the present invention, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. When'include','have','consists of' and the like mentioned in the present specification are used, other parts may be added unless'only' is used. In the case of expressing the constituent elements in the singular, it includes the case of including the plural unless specifically stated otherwise.

In interpreting the constituent elements, it is interpreted as including an error range even if there is no explicit description.

In the case of a description of the positional relationship, for example, if the positional relationship of two parts is described as'upper','upper of','lower of','next to','right' Or, unless'direct' 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, when a temporal predecessor relationship is described as'after','following','after','before', etc.,'right' or'direct' It may also include cases that are not continuous unless this is used.

First, second, etc. are used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one component from another component. Accordingly, the first component mentioned below may be a second component within the technical idea of the present invention.

Each of the features 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 of the embodiments can be implemented independently of each other or can be implemented together in a related relationship. May be.

Hereinafter, an embodiment of the present invention will be described in detail through the accompanying drawings and examples.

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

Organic light-emitting devices are 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 light emission method will be described as an example.

Here, an EL peak of an organic light-emitting display device to which an organic light-emitting device including first, second, and third light-emitting units is applied is a photoluminescence peak that displays a unique color of the light-emitting layer; 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, a first light-emitting unit 110 and a second light-emitting unit disposed between the first and second electrodes 102 and 104. 120) and a third light emitting unit 130.

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

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

Each of the first electrode 102 and the second electrode 104 may be referred to as an anode or a cathode.

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

In the present invention, a third light emitting unit 130 including a first light emitting unit 110, a second light emitting unit 120, and a blue light emitting layer is formed between the first electrode 102 and the second electrode 104, (Blue) It is possible to improve the luminous efficiency of the light emitting layer. In addition, the position of the first electrode 102 from the second electrode 104, the first emission layer of the first emission unit 110, the second emission layer of the second emission unit 120, and the third By setting the light emitting position of the third light emitting layer of the light emitting part 130, light emission efficiency and panel efficiency are improved. That is, an Emission Position of Emitting Layers (EPEL) structure is applied to the first emission layer, the second emission layer, and the third emission layer.

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

A position (L0) of the first electrode 102 is set from the second electrode 104, and a light emission position (L1) of the third light-emitting unit 130 at a position closest to the second electrode 104 ) Is set to be located within the range of 200Å to 800Å. Alternatively, the light emission position L1 of the third light emitting part 130 is set to be located within a range of 200 Å to 800 Å from the reflective surface of the second electrode 104. The third light-emitting unit 130 is 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. ) And a green light emitting layer, or a combination thereof. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

The light emission position L2 of the second light emitting part 120 is set to be located within a range of 1,800 Å to 2,550 Å from the second electrode 104. Alternatively, the light emission position L2 of the second light emitting part 120 is set to be located within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104. The second light emitting part 120 is 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 be composed of one of a yellow-green) emission layer and a red emission layer, or a combination thereof.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L2 of the second emission unit 120 is 1,800 Å to 2,550 Å from the second electrode 104. It should be located within the range of Å. Alternatively, the light emission position L2 of the second light emitting part 120 is set to be located within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104. Accordingly, the emission peak is positioned in a yellow-green emission region, a yellow and red emission region, or a red and green emission region, or a yellow-green and red emission region, and the emission peak ( Emitting Peak) is emitted so that the second light emitting unit 120 emits maximum luminance. The yellow-green light emitting layer may have a peak wavelength range of 510 nm to 580 nm. In addition, a peak wavelength range of the yellow and red emission layers may be 540 nm to 650 nm. In addition, the peak wavelength range of the red and green emission layers may be 510 nm to 650 nm. In addition, a peak wavelength range of the yellow-green and red light-emitting layers may be 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The light emission 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 emission 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 is 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 be composed of one of an emission layer and a green emission layer, or a combination thereof. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer. Since the deep blue emission layer is located in a shorter wavelength region than the blue emission layer, it may be advantageous to improve color reproducibility and brightness.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L3 of the first emission unit 110 is 2,650 Å to 3,300 Å from the second electrode 104. Set to be within the range of Å. Alternatively, the light emission 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. Accordingly, the emission peak of the first light-emitting unit 110 is positioned in the blue light-emitting region so that the first light-emitting unit 110 can emit maximum luminance. The peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, a peak wavelength range of the blue emission layer and the yellow-green emission layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue and red emission layers may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue and green emission layers may be 440 nm to 560 nm. Here, the peak wavelength may be an emission 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 emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, and the second An EPEL (Emission Position of Emitting Layers) structure in which the emission positions of the emission layers are set from the electrode 104 is applied.

2 is a diagram illustrating 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 part 130.

Each of the first electrode 102 and the second electrode 104 may be referred to as an anode or a cathode.

The position of the first electrode 102 is set to be between 4,500 Å and 6,000 Å from the second electrode 104. By setting the position (L0) of the first electrode 102, the emission peak 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 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that specific wavelength. In addition, the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 have a maximum light emission 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.

The third light-emitting unit 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 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.

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

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) or the like, but is not limited thereto.

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

A hole injection layer (HIL) may be additionally 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 emission layer (EML) 134. The hole blocking layer (HBL) prevents the holes generated in the third emission layer (EML) 134 from passing to the third electron transport layer (ETL) 136, thereby preventing the third emission layer (EML) 134 By improving the bonding between electrons and holes, the luminous efficiency of the third emission layer (EML) 134 may be improved. 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 emission layer (EML) 134. The electron blocking layer (EBL) prevents electrons generated in the third emission layer (EML) 134 from passing to the third hole transport layer (HTL) 132, thereby preventing the third emission layer (EML) 134 By improving the bonding between electrons and holes, the luminous efficiency of the third emission layer (EML) 134 may be improved. The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as a single layer.

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

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

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

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

All layers such as the third electron transport layer (ETL) 136, the third emission 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 emission layer (EML) 134 and the third emission layer (EML) 134 may be referred to as an organic layer. Accordingly, all organic layers between the second electrode 104 and the third emission layer (EML) 134 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layers (ETL) 136, regardless of the number or thickness of the third emission layers (EML) 134, or regardless of the number or thickness of the electron injection layers (EIL), Alternatively, regardless of the number or thickness of the hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 104 and the third emission layer (EML) 134, the third emission layer ( The emission position L1 of the EML) 134 is set to be located within a range of 200 Å to 800 Å from the second electrode 104. Alternatively, the light emission position L1 of the third emission 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 emission layer, and the thickness of the third emission layer, the emission position (L1) of the third emission layer (EML) 134 ) May be set to be located within a range of 200 Å to 800 Å from the second electrode 104. Alternatively, the emission position (L1) of the third emission 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 emission layer, and the thickness of the third emission layer. ) May be set to be located 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 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 formed of the same material as the third hole transport layer (HTL) 132, but is not limited thereto.

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

A hole injection layer HIL may be additionally 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 emission layer EML 124. The hole blocking layer (HBL) prevents holes generated in the second emission layer (EML) 124 from passing to the second electron transport layer (ETL) 126, thereby preventing the second emission layer (EML) 124 Emission efficiency of the second emission layer (EML) 124 may be improved by improving the bonding between electrons and holes. The second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the second emission layer EML 124. The electron blocking layer (EBL) prevents electrons generated in the second emission layer (EML) 124 from passing to the second hole transport layer (HTL) 122, thereby preventing the second emission layer (EML) 124 Emission efficiency of the second emission layer (EML) 124 may be improved by improving the bonding between electrons and holes. The second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as a single layer.

The second emission layer (EML) 124 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow- It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 124 may be configured identically or differently above and below the 124.

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

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, the peak wavelength of the emission region of the red and green emission layers may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

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

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

The second emission layer (EML) 124 is a yellow-green emission layer, or a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or yellow- When composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength of the emission region of the second emission layer (EML) 124 is 510 nm to 650 It can be in the range of nm. Here, the peak wavelength may be an emission 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 controls a balance of charges between the second and third light emitting units 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 generation layer serves to inject electrons into the second light-emitting unit 120, and the P-type charge generation layer serves to inject holes into the third light-emitting unit 130. .

The N-type charge generation 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. It is not limited.

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

The second charge generation layer (CGL) 150 may be configured as a single layer.

The second emission 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 layer 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 emission layer (EML) 134 and the second emission layer (EML) 124 and the second emission layer (EML) 124 may be referred to as organic layers. Accordingly, all organic layers between the third emission layer (EML) 134 and the second emission 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, or 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 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 emission layers (EML) 124, or regardless of the number or thickness of the third emission layers (EML) 134, or the second electrode 104 and the third emission layer (EML) Regardless of the number or thickness of all organic layers between) 134, or regardless of the number or thickness of all organic layers between the third emission layer (EML) 134 and the second emission layer (EML) 124, The light emission position L2 of the second emission 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 emission position L2 of the second emission layer EML 124 is set to be located within a range of 1,800 Å to 2,550 Å from the reflective surface of the second electrode 104.

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the emission position L2 of the second emission 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 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 emission layer, the thickness of the third emission layer, Regardless of the number of the second emission layers and the thickness of the second emission layer, the emission position L2 of the second emission 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 within 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 doing.

Although not shown in the drawing, 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 emission layer (EML) 114. The first electron transport layer (ETL) 116 supplies electrons from the second electrode 104 to the first emission layer (EML) 114.

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

In the first emission layer (EML) 114, holes supplied through the first hole transport layer (HTL) 112 and electrons supplied through the first electron transport layer (ETL) 116 are recombined. 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 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 formed of the same material as the third hole transport layer (HTL) 132, but is not 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 emission layer EML 114. The hole blocking layer (HBL) prevents the holes generated in the first emission layer (EML) 114 from passing to the first electron transport layer (ETL) 116, thereby preventing the first emission layer (EML) 114 By improving the bonding of electrons and holes in the first emission layer (EML) 114 may improve the luminous efficiency. The first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 114. The electron blocking layer (EBL) prevents electrons generated in the first emission layer (EML) 114 from passing to the first hole transport layer (HTL) 112 so that the first emission layer (EML) 114 By improving the bonding of electrons and holes in the first emission layer (EML) 114 may improve the luminous efficiency. The first hole transport layer (HTL) 112 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 114 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

When the auxiliary emission layer is formed on the first emission layer (EML) 114, the peak wavelength of the emission region of the first emission layer (EML) 114 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission 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 generation layer (CGL) 140 adjusts the balance of charges between the first and second light emitting units 110 and 120. The first charge generation layer (CGL) 140 may include an N-type charge generation layer and a P-type charge generation layer.

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

The first charge generation layer (CGL) 140 may be formed of the same material of the N-type charge generation layer and the P-type charge generation layer of the second charge generation layer (CGL) 150, but is limited thereto. no.

The first charge generation layer (CGL) 140 may be configured as a single layer.

The first emission 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 layer HBL, the electron blocking layer EBL, and the hole injection layer HIL, may be referred to as organic layers. All organic layers between the second emission layer (EML) 124 and the first emission layer (EML) 114 and the first emission layer (EML) 114 may be referred to as an organic layer. Accordingly, all organic layers between the second emission layer EML 124 and the first emission layer EML 114 may be referred to as a second organic layer.

Regardless of the number or thickness of the second hole transport layers (HTL) 122, regardless of the number or thickness of the first charge generation layers (CGL) 140, or regardless of the number or thickness of the electron blocking layers (EBL) Without, or regardless of the number or thickness of the hole injection layers (HIL), or the number or thickness of the hole blocking layers (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 emission layers (EML) 114, regardless of the number or thickness of the second emission layers (EML) 124, or regardless of the number or thickness of the third emission layers (EML) 134 Without, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third emission layer (EML) 134, or the third emission layer (EML) 134 and the second emission layer ( EML) regardless of the number or thickness of all organic layers between 124, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 124 and the first emission layer (EML) 114 , The emission position L3 of the first emission 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 emission position L3 of the first emission layer EML 114 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.

Accordingly, the number of the at least one 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 third The first emission layer (EML) 114 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, and the thickness of the first emission layer. The light emission position L3 of) may be set to be located within a range of 2,650 Å to 3,300 Å from the second electrode 104. Alternatively, the number of the at least one 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 third The first emission layer (EML) 114 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, and the thickness of the first emission layer. The light emission position L3 of) may be set to be located 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, electron blocking layer (EBL), hole injection layer (HIL), etc. between the first emission layer (EML) 114 and the substrate 101 are referred to as organic layers. can do. Accordingly, all layers between the first emission layer (EML) 114 and the substrate 101 and including the first electrode 102 may be referred to as organic layers. All organic layers between the first emission layer (EML) 114 and the substrate 101 and the first electrode 102 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 112, regardless of the number or thickness of the hole injection layers (HIL), or the number or thickness of the electron blocking layers (EBL), or the first Regardless of the number or thickness of the electrodes 102, or the number or thickness of the first emission layers (EML) 114, or the number or thickness of the second emission layers (EML) 124, or 3 Regardless of the number or thickness of the emission layers (EML) 134, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third emission layer (EML) 134, or the third Regardless of the number or thickness of all organic layers between the emission layer (EML) 134 and the second emission layer (EML) 124, or the second emission layer (EML) 124 and the first emission layer (EML) ( 114) of the first electrode 102 regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 114 and the substrate 101. The position L0 may be set to be located 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 located within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104.

Accordingly, the number of the at least one 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 third The number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, the number of the first organic layers, the first organic layer Regardless of the thickness of the first electrode 102, the position L0 of the first electrode 102 may be set to be located within a range of 4,500 Å to 6,000 Å from the second electrode 104. Alternatively, the number of the at least one 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 third The number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, the number of the first organic layers, the first organic layer Regardless of the thickness of, the position L0 of the first electrode 102 may be set to be located 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 the emission layer constituting the first emission unit 110, the second emission unit 120, and the third emission unit 130, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the This is a diagram illustrating an example of organic layers that may be formed between the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130. Therefore, the present invention is not limited thereto, and may be selectively arranged according to the configuration and characteristics of the device.

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

3 is a diagram illustrating a light emission position of an organic light emitting diode according to a first exemplary 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 emission positions of the emission layers constituting the light emitting unit from the second electrode 104, and may be referred to as a contour map. Here, except for the first electrode 102 and the second electrode 104, when the EPEL structure of the present invention is applied, the emission positions of the emission layers are shown at the emission peak. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown. In FIG. 3, the emission positions of the emission layers are indicated by making the thickness of all organic layers excluding the first electrode 102 and the second electrode 104 4,200 Å. The thickness of the entire organic layers does not limit the content of the present invention.

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

Accordingly, by setting the emission position 134E of the third emission layer (EML) 134 from the second electrode 104 to a range of 200 Å to 800 Å, the emission peak of the third emission layer EML 134 is set. ) 134E is located at a maximum wavelength (B-Max) of 460 nm. Accordingly, the third emission layer (EML) 134 emits light at a maximum wavelength (B-Max) of 460 nm, thereby enabling maximum efficiency. As described above, in FIG. 3, the emission position of the third emission layer (EML) 134 is 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 emission position of the third emission layer (EML) 134 may be in the range of 200 Å to 800 Å. The same may be applied to the light emission position of the second emission layer (EML) 124 and the emission position of the first emission layer (EML) 114.

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

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

Therefore, by setting the light emission position of the second emission layer (EML) 124 from the second electrode 104 to a range of 1,800 Å to 2,550 Å, the emission peak of the second emission layer (EML) 124 Place (124E) at the maximum wavelength (YG-Max) of 560 nm. Accordingly, the second emission layer (EML) 124 emits light at a maximum wavelength (YG-Max) of 560 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 540 nm to 650 nm emission region.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a red emission layer and a green emission layer, depending on the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

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

Accordingly, as the second emission layer (EML) 124, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 124 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

Since the first emission layer (EML) 114 constituting the first emission unit 110 is a blue emission layer, the peak wavelength range of the emission region of the first emission layer (EML) 114 May range from 440 nm to 480 nm. Maximum efficiency can be achieved when light is emitted in a white region of a contour map at a maximum wavelength (B-Max) of the blue emission layer of 460 nm.

Therefore, by setting the light emission position of the first emission layer (EML) 114 from the second electrode 104 to a range of 2,650 Å to 3,300 Å, the emission peak 114E is the maximum wavelength (B-Max) ) Is located at 460nm. Accordingly, the first emission layer (EML) 114 emits light at a maximum wavelength (B-Max) of 460 nm, thereby achieving maximum efficiency.

In addition, as the first emission layer (EML) 114, a blue emission layer and a yellow-green emission layer, or a blue emission layer and a red emission layer, or a blue emission layer and green When one of the (Green) emission layers or a combination thereof is used, the peak wavelength range of the emission region of the first emission layer (EML) 114 may be in the range of 440 nm to 650 nm. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer. Therefore, in this case, the maximum efficiency can be achieved in the white area of the contour map only when the first emission layer (EML) 114 emits light in the emission area of 440 nm to 650 nm.

As described above, the position of the emission peak changes according to the emission position of the emission layer. Accordingly, 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 part.

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the 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 may be 440 nm to 470 nm.

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

That is, in the case of applying the EPEL (Emission Position of Emitting Layers) structure of the present invention and as a comparative example, the emission intensity of the lower emission method of the structure in which a blue emission layer and a yellow-green emission layer are stacked is shown. will be.

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

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

The embodiment (maximum position) is a portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the light emission position L1 of the third emission 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.

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

As shown in FIG. 4, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, compared with the optimum position, the following is. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is a peak wavelength of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. Therefore, the blue light emission efficiency decreases. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

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

In Table 1 below, a comparative example is a white organic light-emitting device of a bottom emission type in which a blue emission layer and a yellow-green emission layer are stacked. In addition, the embodiment is a white organic light-emitting device of a bottom emission type when an optimum position of the Emission Position of Emitting Layers (EPEL) 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 has increased by about 25%. Able to know. In addition, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 19%. It can be seen that the average efficiency has increased by about 20% compared to the comparative example.

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

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 2, at the boundary between the embodiment (minimum position) and the embodiment (maximum position), it can be seen that the efficiency of red, green, blue, and white all decreases. have. In addition, it can be seen that the efficiency of red, green, blue, and white in the embodiment (minimum position) is further reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in the range of 4,500 Å to 6,000 Å from the second electrode.

The emission position of the third emission layer may be set in the range of 200 Å to 800 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 1,800 Å to 2,550 Å from the second electrode.

The emission position of the first emission layer may be set in a range of 2,650 Å to 3,300 Å from the second electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

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

5 is a diagram illustrating a white organic light emitting device according to a second exemplary embodiment of the present invention.

The white organic light-emitting device 100 illustrated 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 the present embodiment, a description of the same or corresponding component as in the previous embodiment will be omitted. The location of the first electrode 102 is 4,500 Å to 6,000 Å from the second electrode 104. Set 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 positioned at a specific wavelength, and light of that specific wavelength By emitting light, the efficiency of the light-emitting layers can be improved. In addition, the first light emitting part 110, the second light emitting part 120, and the third light emitting part 130 have a maximum light emission 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.

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. It 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 additionally formed under the third hole transport layer HTL 132.

A hole blocking layer HBL may be additionally formed on the third emission 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 emission layer EML 134. The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 134 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

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

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

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

All layers such as the third electron transport layer (ETL) 136, the third emission 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 emission layer (EML) 134 and the third emission layer (EML) 134 may be referred to as an organic layer. Accordingly, all organic layers between the second electrode 104 and the third emission layer (EML) 134 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layers (ETL) 136, regardless of the number or thickness of the third emission layers (EML) 134, or regardless of the number or thickness of the electron injection layers (EIL), Alternatively, regardless of the number or thickness of the hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 104 and the third emission layer (EML) 134, the third emission layer (EML) The light emission position L1 of) 134 is set to be located within a range of 300 Å to 700 Å from the second electrode 104. Alternatively, the light emission position L1 of the third emission layer EML 134 is set to be located 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 emission layer, and the thickness of the third emission layer, the emission position (L1) of the third emission layer (EML) 134 ) May be set to be located within 300 Å to 700 Å from the second electrode 104. Alternatively, the emission position (L1) of the third emission 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 emission layer, and the thickness of the third emission 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 additionally formed under the second hole transport layer HTL 122.

A hole blocking layer HBL may be additionally formed on the second emission layer EML 124. In addition, 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 emission layer EML 124. In addition, the second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as a single layer.

The second emission layer (EML) 124 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow- It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 124 may be configured identically or differently above and below the 124.

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

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

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

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

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

A second charge generation 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 emission 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 layer 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 emission layer (EML) 134 and the second emission layer (EML) 124 and the second emission layer (EML) 124 may be referred to as organic layers. Accordingly, all organic layers between the third emission layer (EML) 134 and the second emission 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, or 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 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 emission layers (EML) 124, or regardless of the number or thickness of the third emission layers (EML) 134, or the second electrode 104 and the third emission layer (EML) Regardless of the number or thickness of all organic layers between) 134, or regardless of the number or thickness of all organic layers between the third emission layer (EML) 134 and the second emission layer (EML) 124, The emission position L2 of the second emission 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 emission position L2 of the second emission layer EML 124 is set to be located within a range of 1,900 Å to 2,400 Å from the reflective surface of the second electrode 104.

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the emission position L2 of the second emission 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, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the emission position L2 of the second emission 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

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 doing.

Although not shown in the drawing, 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. In addition, 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 emission layer EML 114. The first electron transport layer (ETL) 116 and the hole blocking layer (HBL) may be configured as a single layer.

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

The first emission layer (EML) 114 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

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

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

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

The first emission 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 layer HBL, the electron blocking layer EBL, and the hole injection layer HIL, may be referred to as organic layers. All organic layers between the second emission layer (EML) 124 and the first emission layer (EML) 114 and the first emission layer (EML) 114 may be referred to as an organic layer. Accordingly, all organic layers between the second emission layer EML 124 and the first emission layer EML 114 may be referred to as a second organic layer.

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

Accordingly, the number of the at least one 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 third The first emission layer (EML) 114 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, and the thickness of the first emission layer. The light emission position L3 of) may be set to be located within a range of 2,800 Å to 3,200 Å from the second electrode 104. Alternatively, the number of the at least one 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 third The first emission layer (EML) 114 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, and the thickness of the first emission layer. The light emission position L3 of) 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, electron blocking layer (EBL), hole injection layer (HIL), etc. between the first emission layer (EML) 114 and the substrate 101 are referred to as organic layers. can do. Accordingly, all layers that are between the first emission layer (EML) 114 and the substrate 101 and including the first electrode 102 may be referred to as organic layers, and the first emission layer (EML) 114 All organic layers between the and the substrate 101 and the first electrode 102 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 112, regardless of the number or thickness of the hole injection layers (HIL), or the number or thickness of the electron blocking layers (EBL), or the first Regardless of the number or thickness of the electrodes 102, or the number or thickness of the first emission layers (EML) 114, or the number or thickness of the second emission layers (EML) 124, or 3 Regardless of the number or thickness of the emission layers (EML) 134, or regardless of the number or thickness of all organic layers between the second electrode 104 and the third emission layer (EML) 134, or the third Regardless of the number or thickness of all organic layers between the emission layer (EML) 134 and the second emission layer (EML) 124, or the second emission layer (EML) 124 and the first emission layer (EML) ( 114) Regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 114 and the substrate 101, the first electrode 102 The position L0 of may be set to be located 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 located within a range of 4,500 Å to 6,000 Å from the reflective surface of the second electrode 104.

Accordingly, the number of the at least one 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 third The number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, the number of the first organic layers, the first organic layer Regardless of the thickness of the first electrode 102, the position L0 of the first electrode 102 may be set to be located within a range of 4,500 Å to 6,000 Å from the second electrode 104. Alternatively, the number of the at least one 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 third The number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, the number of the first organic layers, the first organic layer Regardless of the thickness of, the position L0 of the first electrode 102 may be set to be located 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 may be selectively configured according to a structure or characteristic of an organic light-emitting device, but is not limited thereto.

6 is a diagram illustrating a light emission position of an organic light emitting diode according to a second exemplary 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 emission positions of the emission layers constituting the light emitting unit from the second electrode 104, and may be referred to as a contour map. Here, except for the first electrode 102 and the second electrode 104, when the EPEL structure of the present invention is applied, the emission positions of the emission layers are shown at the emission peak. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown. In FIG. 6, the emission positions of the emission layers are shown with the thickness of all organic layers except for the first electrode 102 and the second electrode 104 being 4,200 Å. The thickness of the entire organic layers does not limit the content of the present invention.

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

Accordingly, the emission position of the third emission layer (EML) 134 is set in the range of 300 Å to 700 Å, so that the emission peak 134E of the third emission layer (EML) 134 is the maximum wavelength (B-Max). ) Is located at 460nm. Accordingly, the third emission layer (EML) 134 is made to emit light at a maximum wavelength (B-Max) of 460 nm, thereby achieving maximum efficiency. In FIG. 6, the emission position 134E of the third emission layer (EML) 134 is 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 emission position of the third emission layer (EML) 134 may be in the range of 200 Å to 800 Å. The same may be applied to the light emission position of the second emission layer (EML) 124 and the emission position of the first emission layer (EML) 114.

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

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

Accordingly, by setting the emission position of the second emission layer (EML) 124 in the range of 1,900 Å to 2,400 Å, an emission peak 124E corresponding to the emission region of the second emission layer EML 124 Is located at the maximum wavelength (YG-Max) of 560 nm. Accordingly, the second emission layer (EML) 124 emits light at a maximum wavelength (YG-Max) of 560 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 540 nm to 650 nm emission region.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a red emission layer and a green emission layer, depending on the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

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

Accordingly, as the second emission layer (EML) 124, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 124 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

Since the first emission layer (EML) 114 constituting the first emission unit 110 is a blue emission layer, the peak wavelength range of the emission region of the first emission layer (EML) 114 May range from 440 nm to 480 nm. Maximum efficiency can be achieved when light is emitted in a white region of a contour map at a maximum wavelength (B-Max) of the blue emission layer of 460 nm.

Accordingly, the emission position of the first emission 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 the maximum wavelength (B-Max) of 460 nm. . Accordingly, the maximum efficiency can be achieved by making the first emission layer (EML) 114 emit light at a maximum wavelength (B-Max) of 460 nm.

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

As described above, the position of the emission peak changes according to the emission position of the emission layer. Accordingly, 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 part.

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the 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 may be 440 nm to 470 nm.

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

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

That is, in the case of applying the EPEL (Emission Position of Emitting Layers) structure of the present invention and as a comparative example, the emission intensity of the lower emission method of the structure in which a blue emission layer and a yellow-green emission layer are stacked is shown. will be.

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

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

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

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

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

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. Therefore, the blue light emission efficiency decreases. In addition, it can be seen that the light emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light, and out of the peak wavelength range of yellow-green light.

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

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

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

As shown in Table 3, 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 has increased by about 25%. Able to know. In addition, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 19%. It can be seen that the average efficiency has increased by about 20% compared to the comparative example.

The panel efficiency of the white organic light emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 4 below.

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 4, at the boundary between the embodiment (minimum position) and the embodiment (maximum position), it can be seen that the efficiencies of green, blue, and white are all reduced. In addition, when comparing Table 2 of the first embodiment of the present invention with Table 4 of the second embodiment of the present invention, the boundary between the embodiment (minimum position) and the embodiment (maximum position) is green and blue. ) And white (white) efficiency was further improved. Accordingly, according to the second exemplary embodiment of the present invention, an organic light emitting display device having 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 further reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in the range of 4,500 Å to 6,000 Å from the second electrode.

The emission position of the third emission layer may be set in a range of 300 Å to 700 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 1,900 Å to 2,400 Å from the second electrode.

The emission position of the first emission layer may be set in a range of 2,800 Å to 3,200 Å from the second electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

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

8 is a diagram illustrating a white organic light emitting device according to a third exemplary embodiment of the present invention.

In this embodiment, the emission positions of the emission layers are set from the first electrode, and the emission positions may be set from the first electrode according to the device design.

The position of the second electrode 104 is set to be 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 positioned at a specific wavelength, and light of that specific wavelength By emitting light, the efficiency of the light-emitting layers can be improved. In addition, the first emission part, the second emission part, and the third emission part have a maximum emission range in the emission regions of the first emission layer, the second emission layer, and the third emission layer (Emission Position of Emitting Layers). It has 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 doing.

Although not shown in the drawing, 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 emission layer EML 114. In addition, 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 emission layer EML 114. In addition, the first hole transport layer (HTL) 112 and the electron blocking layer (EBL) may be configured as one layer.

The first emission layer (EML) 114 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

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

When the auxiliary emission layer is formed on the first emission layer (EML) 114, the peak wavelength of the emission region of the first emission layer (EML) 114 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission 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 emission layer (EML) 114 and the first electrode 102 may be referred to as an organic layer. Accordingly, all organic layers between the substrate 101 and the first emission layer (EML) 114 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 first electrode 102, 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), or regardless of the number or thickness of all organic layers between the substrate 101 and the first emission layer (EML) 114, the first emission layer (EML) 114 The light emission position L1 of is set to be located within a range of 2,000 Å to 2,650 Å from the first electrode 102. Alternatively, the emission position L3 of the first emission 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 the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer (EML) 114 is 2,000 Å to 2,650 from the first electrode 102. It can be set to be within the range of Å. Alternatively, regardless of the number of the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer (EML) 114 is the substrate 101 and the first electrode 102 ) Can be set to be located in the range of 2,000 Å to 2,650 Å from the interface.

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 additionally formed under the second hole transport layer HTL 122.

A hole blocking layer HBL may be additionally formed on the second emission layer EML 124. In addition, 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 emission layer EML 124. In addition, the second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as a single layer.

The second emission layer (EML) 124 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow- It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 124 may be configured identically or differently above and below the 124.

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

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

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

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

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

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

The first emission 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 layer 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 emission layer (EML) 114 and the second emission layer (EML) 124 and the first emission layer (EML) 114 may be referred to as an organic layer. Accordingly, all organic layers between the first emission layer (EML) 114 and the second emission layer (EML) 124 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layers (ETL) 116, regardless of the number or thickness of the second hole transport layers (HTL) 122, or of the first charge generation layer (CGL) 140 Regardless of the number or thickness of the hole blocking layers (HBL), regardless of the number or thickness of the electron blocking layers (EBL), or the number or thickness of the hole injection layers (HIL), or the above Regardless of the number or thickness of the first emission layers (EML) 114, regardless of the number or thickness of all organic layers between the substrate 101 and the first emission layer (EML) 114, or the first emission layer Regardless of the number or thickness of all organic layers between the (EML) 114 and the second emission layer (EML) 124, the emission position (L2) of the second emission layer (EML) 124 is the first electrode It is set to be located in the range of 2,750 Å to 3,500 Å from (102). Alternatively, the light emission position L2 of the second emission layer EML 124 may be set to be located 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The light emission position L2 of the second emission 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 the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The emission position L2 of the second emission layer EML 124 may be set to be located in 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. It 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 additionally formed under the third hole transport layer (HTL) 132. A hole blocking layer (HBL) may be additionally formed on the third emission 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 emission layer EML 134. The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 134 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

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

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

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

Regardless of the number or thickness of the second emission layers (EML) 124, regardless of the number or thickness of the second electron transport layers (ETL) 126, or the number or thickness of the third hole transport layers (HTL) 132 Regardless of, regardless of the number or thickness of the second charge generation layers (CGL) 150, regardless of the number or thickness of the hole injection layers (HIL), or regardless of the number or thickness of the electron blocking layers (EBL) Without, or regardless of the number or thickness of the hole blocking layers (HBL), or regardless of the number or thickness of the first emission layers (EML) 114, or the substrate 101 and the first emission layer (EML) 114 ), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 114 and the second emission layer (EML) 124, or 2 Regardless of the number or thickness of all organic layers between the emission layer (EML) 124 and the third emission layer (EML) 134, the emission position (L3) of the third emission layer (EML) 134 is It is set to be located within the range of 4,500 Å to 5,100 Å from the electrode 102. Alternatively, the emission position L3 of the third emission layer EML 134 may be set to be located 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 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 third organic layers, the thickness of the third organic layer, the first Regardless of the number of emission layers, the thickness of the first emission layer, the number of the second emission layers, and the thickness of the second emission layer, the emission position (L3) of the third emission layer (EML) 134 is the first electrode 102 ) Can be set to be located in the range of 4,500Å to 5,100Å. Alternatively, at least one 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 third organic layers, the thickness of the third organic layer, the first Regardless of the number of emission layers, the thickness of the first emission layer, the number of the second emission layers, and the thickness of the second emission layer, the emission position L3 of the third emission layer (EML) 134 is equal to the substrate 101 It may be set to be located within a range of 4,500 Å to 5,100 Å from the interface of the first electrode 102.

Further, all layers such as the third emission 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 emission layer (EML) 134 and the second electrode 104 and the third emission layer (EML) 134 may be referred to as an organic layer. Accordingly, all organic layers between the third emission 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 electron injection layers (EIL), or regardless of the number or thickness of hole blocking layers (HBL), or the third Regardless of the number or thickness of the emission layers (EML) 134, regardless of the number or thickness of the second emission layers (EML) 124, or regardless of the number or thickness of the first emission layers (EML) 114, Alternatively, regardless of the number or thickness of all organic layers between the substrate 101 and the first emission layer (EML) 114, or the first emission layer (EML) 114 and the second emission layer (EML) 124 ), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 124 and the third emission layer (EML) 134, or 3 Regardless of the thickness of all organic layers between the emission layer (EML) 134 and the second electrode 104, the position (L0) of the second electrode 104 is 4,500 Å from the first electrode 102 It can be set to be located in the range of to 6,000Å. Alternatively, 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 interface between the substrate 101 and the first electrode 102.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 104, 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. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 104, 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 interface between the substrate 101 and the first electrode 102.

Here, the light emission position L3 of the third emission layer EML 134 may be set to be located within a range of 4,500 Å to 5,100 Å from the first electrode 102. In addition, 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. When the light emission position L3 of the third emission layer EML 134 is set to 4,500Å from the first electrode 102, the position L0 of the second electrode 104 is the first electrode ( 102) can be set to be located in the range of 4,550Å to 6,000Å. In addition, when the light emission position L3 of the third emission layer EML 134 is set to 5,100Å from the first electrode 102, the position L0 of the second electrode 104 is the first It can be set to be located within the 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 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 third organic layers, the thickness of the third organic layer, The number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the Regardless of the thickness of the third emission layer, the position of the second electrode 104 and the position of the emission layers from the first electrode 102 may be set.

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

9 is a diagram illustrating a light emission position of an organic light emitting diode according to a third exemplary 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 emission positions of the emission layers constituting the light emitting unit from the first electrode 102, and may 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 emission positions of the emission layers are shown at the emission peak. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown. Since the first emission layer (EML) 114 constituting the first emission unit 110 is a blue emission layer, the peak wavelength range of the emission region of the first emission layer (EML) 114 May range from 440 nm to 480 nm. Maximum efficiency can be achieved when light is emitted in a white region of a contour map at a maximum wavelength (B-Max) of the blue emission layer of 460 nm.

Accordingly, the emission position of the first emission 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 the maximum wavelength (B-Max) of 460 nm. . Accordingly, the maximum efficiency can be achieved by making the first emission layer (EML) 114 emit light at a maximum wavelength (B-Max) of 460 nm.

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

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

Accordingly, by setting the emission position of the second emission layer (EML) 124 in the range of 2,750 Å to 3,500 Å, an emission peak 124E corresponding to the emission region of the second emission layer (EML) 124 Is located at the maximum wavelength (YG-Max) of 560 nm. Accordingly, the second emission layer (EML) 124 emits light at a maximum wavelength (YG-Max) of 560 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 540 nm to 650 nm emission region.

In addition, the second emission layer (EML) 124 of the second emission unit 120 may be formed of two layers, a red emission layer and a green emission layer, depending on the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

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

Accordingly, as the second emission layer (EML) 124, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 124 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the second emission layer (EML) 124 emits light in the 510 nm to 650 nm emission region.

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

Accordingly, the emission position of the third emission layer (EML) 134 is set in the range of 4,500 Å to 5,100 Å, so that the emission peak 134E of the third emission layer (EML) 134 is at the maximum wavelength (B). -Max) of 460nm. Accordingly, the third emission layer (EML) 134 is made to emit light at a maximum wavelength (B-Max) of 460 nm, thereby achieving maximum efficiency.

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

As described above, the position of the emission peak changes according to the emission position of the emission layer. Accordingly, 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 part.

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

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

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

That is, in the case of applying the EPEL (Emission Position of Emitting Layers) structure of the present invention and as a comparative example, the emission intensity of the lower emission method of the structure in which a blue emission layer and a yellow-green emission layer are stacked is shown. In FIG. 10, the horizontal axis represents the wavelength range of light, and the vertical axis represents the intensity of light emission. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 10, the embodiment (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L1 of the first emission 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 portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the emission position L1 of the first emission 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.

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

As shown in FIG. 10, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, compared with the optimum position, it is as follows. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. Further, it can be seen that the peak wavelength range is out of the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. Therefore, the blue light emission efficiency decreases. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

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

In Table 5 below, a comparative example is a white organic light-emitting device of a bottom emission type having a structure in which a blue emission layer and a yellow-green emission layer are stacked. In addition, the embodiment is a white organic light-emitting device of a bottom emission type when an optimum position of the Emission Position of Emitting Layers (EPEL) 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. In addition, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 19%. It can be seen that the average efficiency has increased by about 20% compared to the comparative example.

The panel efficiency of the white organic light emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 6 below.

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 6, at the boundary between the embodiment (minimum position) and the embodiment (maximum position), it can be seen that the efficiency of red, green, blue, and white all decreases. have. In addition, it can be seen that the efficiency of red, green, blue, and white is further 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 EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in the range of 4,500 Å to 6,000 Å from the first electrode.

The emission position of the first emission layer may be set in the range of 2,000 Å to 2,650 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 2,750 Å to 3,500 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 4,500 Å to 5,100 Å from the first electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 device 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 illustrates the organic light-emitting device according to the first, second, and third embodiments of the present invention. I used it.

11, the organic light emitting display device 1000 according to the present invention includes a substrate 10, a thin film transistor (TFT), an overcoat 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 illustrated in an inverted staggered structure, but may be formed in a coplanar structure.

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

The gate electrode 1115 is formed on the substrate 10 and is connected to a gate line (not shown). The gate electrode 1115 is in 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 multilayer made of any one selected 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), an oxide semiconductor, or an organic semiconductor. Can be formed by 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. In addition, 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 molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni ), neodymium (Nd) and copper (Cu), or any one selected from the group consisting of 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 multiple layers thereof. Alternatively, it may be formed of an acrylic resin, a polyimide resin, or the like, but is not limited thereto.

The color filter 1145 is formed on the first passivation layer 1140, and only one subpixel is shown in the drawing, but the color filter 1145 is formed in the red subpixel, blue subpixel, and green subpixel regions. 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 or polyimide resin, an oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof, but limited thereto. It doesn't work.

The first electrode 102 is formed on the overcoat layer 1150. The first electrode 102 drains the drain through a contact hole CH in a predetermined region of the protective layer 1140 and the overcoat layer 1150. It is electrically connected to the electrode 1135. In FIG. 11, the drain electrode 1135 and the first electrode 1102 are shown to be electrically connected, but the source electrode 1140 and the overcoating layer 1150 through a contact hole CH in a predetermined region. 1133 and the first electrode 102 may be electrically connected.

The 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 region between a plurality of pixels, so that a pixel region is defined by the bank layer 1170. The bank layer 1170 may be formed of an organic material such as a benzocyclobutene (BCB) resin, an acryl resin, or a polyimide resin. Alternatively, the bank layer 1170 may be formed of a photosensitive material including a black pigment, and 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 unit 1180 includes a first light emitting unit 110 formed on the first electrode 102, and a second light emitting unit. It consists of a portion 120 and a third light emitting portion 130.

The 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 encapsulation part serves to prevent moisture from penetrating into the light emitting part 1180. The encapsulation portion may be formed of a plurality of layers in which different inorganic materials are stacked, or may be formed of 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 portion. The encapsulation substrate may be made of glass or plastic, or may be made of metal. The encapsulation substrate may be adhered to the encapsulation portion by an adhesive.

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

Accordingly, through several experiments, the inventors of the present invention invented a white organic light-emitting device of a new structure with improved luminance and aperture ratio because the luminous efficiency and panel efficiency of the emission layer can be improved, and since no polarizing plate is used. I did. In addition, compared to the organic light emitting display device to which the lower light emitting method is applied, the organic light emitting display device to which the upper light emitting method according to an embodiment of the present invention is applied may have an improved aperture ratio.

12 is a schematic diagram showing a white organic light emitting diode 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 part 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. , Is not necessarily limited thereto. Alternatively, it may be formed of transparent conductive materials such as TCO (Transparent Conductive Oxide), such as ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), etc., but is not limited thereto.

The second electrode 204 is a cathode that supplies electrons and is formed of transparent conductive materials such as TCO (Transparent Conductive Oxide), Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Indium Gallium Zinc Oxide (IGZO), and the like. May be, but is not 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 thereto. Alternatively, the second electrode 204 is TCO (Transparent Conductive Oxide), ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide) and metallic materials such as gold (Au), silver (Ag) , Aluminum (Al), molybdenum (Mo), magnesium (Mg) and the like may be formed of two layers, but is not limited thereto.

Each of the first electrode 202 and the second electrode 204 may be referred to as an anode or a cathode.

In addition, the first electrode 202 may be a reflective electrode, and the second electrode 204 may be configured as a transflective electrode.

The white organic light emitting device 200 of the top emission type of the present invention includes a first light emitting part 210, a second light emitting part 220, and a first electrode 202 and a second electrode 204, respectively. It includes a third light emitting unit 230. In addition, the white organic light-emitting device 200 of the top emission method of the present invention sets the position of the second electrode from the first electrode and the emission positions of the first emission layer, the second emission layer, and the third emission layer. Thus, luminance, luminous efficiency and panel efficiency have been improved. That is, an Emission Position of Emitting Layers (EPEL) structure is applied to the first emission layer, the second emission layer, and the third emission layer. In addition, the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 have a maximum light emission 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.

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 between 4,700 Å and 5,400 Å from the reflective surface of the first electrode 202. In addition, the emission peak of the light emitting layer constituting the first light emitting part 210, the second light emitting part 220, and the third light emitting part 230 is positioned at a specific wavelength, and the light of that specific wavelength Light emission efficiency can be improved by emitting light. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

A position (L0) of the second electrode 204 is set from the first electrode 202, and a light emission position (L1) of the first light-emitting unit 210 located at a position closest to the first electrode 202 ) Is set to be between 150Å and 700Å. Alternatively, the light emission 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 formed of a blue light-emitting layer. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L1 of the first emission unit 210 is in the range of 150 Å to 700 Å from the first electrode 202 To be located within. Alternatively, the light emission position L1 of the first light emitting part 210 is positioned within a range of 150 Å to 700 Å from the reflective surface of the first electrode 202. Accordingly, the first light-emitting unit 210 can emit maximum luminance by making the emission peak positioned in the blue emission region and emitting light having a wavelength corresponding to the emission 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 part 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, a peak wavelength of the emission region of the emission layer including the auxiliary emission layer and constituting the first emission unit 210 may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region.

The light emission position L2 of the second light emitting part 220 is set to be between 1,600 Å and 2,300 Å from the first electrode 202. Alternatively, the light emission position L2 of the second light emitting part 220 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.

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

Accordingly, the second light-emitting unit 220 achieves maximum luminance by making the emission peak positioned in the yellow-green emission region and emitting light having a wavelength corresponding to the emission peak. To be able to pay. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be an emission region.

In addition, the second light-emitting unit 220 may be formed of two layers of a red light-emitting layer and a green light-emitting layer, depending on the characteristics or structure of the device. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved. Accordingly, the peak wavelength of the emission region of the red and green emission layers may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

In addition, the second light-emitting unit 220 may include two layers of a red light-emitting layer and a yellow-green light-emitting layer according to the characteristics or structure of the device. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In addition, the peak wavelength of the emission region of the red and yellow-green emission layers may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

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

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

The light emission position L3 of the third light emitting part 230 is set to be located within a range of 2,400 Å to 3,100 Å from the first electrode 202. Alternatively, the light emission position L3 of the third light emitting part 230 is set to be located 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 formed of a blue light emitting layer. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

Accordingly, the emission peak of the third light-emitting unit 230 is positioned in a blue light-emitting region so that the third light-emitting unit 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. The third light emitting part 230 may be formed of one of a red light emitting layer, a green light emitting layer, a yellow-green light emitting layer, or a combination thereof as an auxiliary light emitting layer. In addition, a peak wavelength of the emission region of the emission layer including the auxiliary emission layer and constituting the third emission unit 230 may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region.

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

13 is a schematic diagram illustrating a white organic light emitting diode according to a fourth exemplary embodiment of the present invention.

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

Each of the first electrode 202 and the second electrode 204 may be referred to as an anode or a cathode.

In addition, the first electrode 202 may be a reflective electrode, and the second electrode 204 may be configured as a transflective electrode.

Referring to FIG. 13, the position of the second electrode 204 is set to be 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, the emission peak 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 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that 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 doing.

An auxiliary electrode 203 may be formed on the first electrode 202. The auxiliary electrode 203 is composed of indium tin oxide (ITO), indium zinc oxide (IZO), indium gallium zinc oxide (IGZO), etc., which are transparent conductive materials such as metal oxide or transparent conductive oxide (TCO). And, it is not necessarily limited thereto.

Although not shown in the drawing, the first light emitting unit 210 may additionally constitute 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 emission layer (EML) 214. The first electron transport layer (ETL) 216 supplies electrons from the first charge generation layer (CGL) 240 to the first emission layer (EML) 214.

In the first emission 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 emission layer (EML) 214. Movement may be difficult, holes may be difficult to move to the first emission layer (EML) 214, and a driving voltage may increase. The auxiliary electrode 203 may not be configured depending on the characteristics or structure of the device.

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 emission layer EML 214. The hole blocking layer (HBL) prevents the holes generated in the first emission layer (EML) 214 from passing to the first electron transport layer (ETL) 216 so that the first emission layer (EML) 214 By improving the bonding between electrons and holes, the light emission efficiency of the first emission layer (EML) 214 may be improved. The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 214. The electron blocking layer (EBL) prevents electrons generated in the first emission layer (EML) 214 from passing to the first hole transport layer (HTL) 212, thereby preventing the first emission layer (EML) 214 By improving the bonding between electrons and holes, the light emission efficiency of the first emission layer (EML) 214 may be improved. The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 214 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

When the auxiliary emission layer is formed on the first emission layer (EML) 214, the peak wavelength of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission 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 emission layer (EML) 214 and the auxiliary electrode 203 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 202 and the first emission layer (EML) 214 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (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 a 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 202 and the first emission layer (EML) 214, the first emission layer (EML) 214 The light emission position L1 of is set to be located within a range of 150 Å to 700 Å from the first electrode 202. Alternatively, the light emission position L1 of the first emission 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. Accordingly, the position (L1) of the first emission layer (EML) 214 from the first electrode 202 is in the range of 150 Å to 700 Å, regardless of the number of the at least one first organic layer and the thickness of the first organic layer. Can be set to be located within. Alternatively, regardless of the number of the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer EML 214 is 150 Å from the reflective surface of the first electrode 202 It can be set to be located in the range of to 700Å.

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 formed of the same material as the first hole transport layer (HTL) 212, but is not limited thereto.

A hole injection layer (HIL) may be additionally 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 limited thereto.

A hole blocking layer HBL may be additionally formed on the second emission layer EML 224. The hole blocking layer (HBL) prevents the holes generated in the second emission layer (EML) 224 from passing to the second electron transport layer (ETL) 226, thereby preventing the second emission layer (EML) 224 By improving the bonding between electrons and holes, the luminous efficiency of the second emission layer (EML) 224 may be improved. The second electron transport layer (ETL) 226 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the second emission layer EML 224. The electron blocking layer (EBL) prevents electrons generated in the second emission layer (EML) 224 from passing to the second hole transport layer (HTL) 222, thereby preventing the second emission layer (EML) 224 By improving the bonding between electrons and holes, the luminous efficiency of the second emission layer (EML) 224 may be improved. The second hole transport layer (HTL) 222 and the electron blocking layer (EBL) may be configured as a single layer.

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

The second emission layer (EML) 224 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow- It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 224 may be configured identically or differently above and below the 224.

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

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

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

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

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

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

The first charge generation layer (CGL) 240 may be configured as a single layer.

The first emission layer (EML) 214, the first electron transport layer (ETL) 216, the first charge generation layer (CGL) 240, the second hole transport layer 222, a hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL), and the like may be referred to as organic layers. All organic layers between the first emission layer (EML) 214 and the second emission layer (EML) 224 and the first emission layer (EML) 214 may be referred to as an organic layer. Accordingly, all organic layers between the first emission layer (EML) 214 and the second emission 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 layers (CGL) 240, or regardless of the number or thickness of the hole blocking layers (HBL), or Regardless of the number or thickness of the electron blocking layers (EBL), the number or thickness of the hole injection layers (HIL), or the number or thickness of the first emission layer (EML) 214, or the first electrode Regardless of the number or thickness of all organic layers between 202 and the first emission layer (EML) 214, or between the first emission layer (EML) 214 and the second emission layer (EML) 224 Regardless of the number or thickness of all organic layers, the light emission position L2 of the second emission 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 emission position L2 of the second emission 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The position L2 of the second emission layer EML 224 from the first electrode 202 may be set to be located within a range of 1,600 Å to 2,300 Å. Alternatively, regardless of the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The position L2 of the second emission layer EML 224 from the reflective surface of the first electrode 202 may be set to be located 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) or the like, but is not limited thereto.

The third hole transport layer (HTL) 232 may be formed 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 limited thereto.

A hole injection layer HIL may be additionally 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, etc. It is not necessarily limited thereto.

The third electron transport layer (ETL) 236 may be formed 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 limited thereto.

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

The N-type charge generation layer (N-CGL) serves to inject electrons into the second light-emitting unit 220, and the P-type charge generation layer (P-CGL) is used as the third light-emitting unit 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 limited thereto.

The P-type charge generation layer P-CGL may be formed of an organic layer containing a P-type dopant, but is not limited thereto.

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

The second charge generation layer (CGL) 250 may be configured as a single layer.

A hole blocking layer HBL may be additionally formed on the third emission layer EML 234. The hole blocking layer (HBL) prevents the holes generated in the third emission layer (EML) 234 from passing to the third electron transport layer (ETL) 236, thereby preventing the third emission layer (EML) 234 By improving the bonding between electrons and holes, the luminous efficiency of the third emission layer (EML) 234 may be improved. 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 additionally formed under the third emission layer EML 234. The electron blocking layer (EBL) prevents electrons generated in the third emission layer (EML) 234 from passing to the third hole transport layer (HTL) 232 so that the third emission layer (EML) 234 By improving the bonding between electrons and holes, the luminous efficiency of the third emission layer (EML) 234 may be improved. The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 234 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

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

Further, all layers such as the third emission 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 emission layer (EML) 234 and the second electrode 204, the second electrode 204, and the third emission layer (EML) 234 may be referred to as organic layers. Accordingly, all organic layers that are between the third emission 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 electron injection layers (EIL), or regardless of the number or thickness of hole blocking layers (HBL), or the second Regardless of the number or thickness of the electrodes 204, or regardless of the number or thickness of the third emission layer (EML) 234, or between the substrate 201 and the first emission 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 emission layer (EML) 214 and the second emission layer (EML) 224, or the second emission layer (EML) Regardless of the number or thickness of all organic layers between (224) and the third emission layer (EML) 234, or of all organic layers between the third emission 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 located within a range of 4,700 Å to 5,400 Å from the reflective surface of the first electrode 202.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 204, 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. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 204, 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 reflective surface of the first electrode 202.

The structure shown in FIG. 13 shows an example of the present invention, and may 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 illustrating a light emission position of an organic light emitting diode according to a fourth exemplary embodiment of the present invention.

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

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

Accordingly, the emission position of the first emission 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. Accordingly, the first emission layer (EML) 214 is allowed to emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the first emission layer (EML) 214 constituting the first emission part 210. In this case, the peak wavelength range of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 214 emits light in the 440 nm to 650 nm emission region.

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

Since the second emission layer (EML) 224 constituting the second emission part 220 is a yellow-green emission layer, the peak wavelength of the emission region of the second emission layer (EML) 224 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Therefore, by setting the emission position of the second emission layer (EML) 224 to be located within the range of 1,600 Å to 2,300 Å, the emission peak 224E of the second emission layer (EML) 224 is 510 nm. To 580 nm. Accordingly, the second emission layer (EML) 224 emits light at 510 nm to 580 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 is composed of two layers, a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light in the 540 nm to 650 nm emission region.

Accordingly, as the second emission layer (EML) 224, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 224 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the second emission layer (EML) 224 emits light in the 510 nm to 650 nm region.

In FIG. 14, the second emission layer (EML) 224 does not include an auxiliary emission layer, and the second emission layer (EML) 224 shows a light emission position by taking a yellow-green emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 224 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

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

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

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 234 constituting the third emission part 230. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 234 emits light from 440 nm to 650 nm.

In FIG. 14, the third emission layer (EML) 234 does not include an auxiliary emission layer, and the third emission layer (EML) 234 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 234 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

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

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

In addition, a light emission range capable of maximizing the efficiency of the light emitting layers at the specific wavelength may be referred to as a maximum light emission range. 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 may be 440 nm to 470 nm.

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

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

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

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

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

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

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

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

In Table 7 below, a 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 The yellow-green light emitting layer and the third light emitting part are formed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 39%, It can be seen that the green efficiency has increased by 63%. And, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 53%.

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

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 8, it can be seen that the efficiency of red, green, blue, and white decreases 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 further reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in a range of 4,700 Å to 5,400 Å from the first electrode.

The emission position of the first emission layer may be set in the range of 150 Å to 700 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 1,600 Å to 2,300 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 2,400 Å to 3,100 Å from the first electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 diode according to a fifth embodiment of the present invention. In describing the present embodiment, descriptions of components that are the same as or corresponding to 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 a first electrode 202 and a second electrode 204, and between the first and second electrodes 202 and 204, and a second light emitting device. A unit 220 and a third light emitting unit 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, the emission peak 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 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that 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 doing.

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 unit 210 may additionally configure a hole injection layer HIL on the auxiliary electrode 203. A hole blocking layer HBL may be additionally formed on the first emission layer EML 214. The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 214. The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 214 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

When the auxiliary emission layer is formed on the first emission layer (EML) 214, the peak wavelength of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission 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 emission layer (EML) 214 and the auxiliary electrode 203 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 202 and the first emission 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 emission layer (EML) 214, the first emission layer (EML) 214 The light emission position L1 of) is set to be located within a range of 150 Å to 650 Å from the first electrode 202. Alternatively, the emission position L1 of the first emission 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. Accordingly, the position (L1) of the first emission layer (EML) 214 from the first electrode 202 is in the range of 150 Å to 650 Å, regardless of the number of the at least one first organic layer and the thickness of the first organic layer. It can be set to be located within. Alternatively, regardless of the number of the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer EML 214 is 150 Å from the reflective surface of the first electrode 202 It can be set to be located within the range of to 650Å.

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 additionally formed under the second hole transport layer (HTL) 222.

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

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

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

In addition, the second emission layer (EML) 124 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 224 may be configured identically or differently above and below the 224.

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

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

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

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

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

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

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

Regardless of the number or thickness of the first electron transport layers (ETL) 216, regardless of the number or thickness of the second hole transport layers (HTL) 222, or the first charge generation layer (CGL) 240 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 emission layer (EML) 214, or regardless of the number or thickness of all organic layers between the first electrode 202 and the first emission layer (EML) 214, or Regardless of the number or thickness of all organic layers between the first emission layer (EML) 214 and the second emission layer (EML) 224, the emission position (L2) of the second emission layer (EML) 224 is The first electrode 202 is set to be located within a range of 1,700 Å to 2,300 Å. Alternatively, the emission position L2 of the second emission 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The position L1 of the second emission layer EML 224 from the first electrode 202 may be set to be located within a range of 1,700 Å to 2,300 Å. Alternatively, regardless of the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The position L1 of the second emission layer EML 224 from the reflective surface of the first electrode 202 may be set to be located 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 additionally formed under the third hole transport layer HTL 232. A second charge generation layer (CGL) 250 may be further formed between the second light emitting unit 220 and the third light emitting unit 230. The second charge generation layer (CGL) 250 may include An N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL) may be included.

A hole blocking layer HBL may be additionally formed on the third emission 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 additionally formed under the third emission layer EML 234. The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 234 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

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

Further, all layers such as the third emission 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 emission layer (EML) 234 and the second electrode 204 and the second electrode 204 may be referred to as an organic layer. Accordingly, all organic layers that are between the third emission 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 electron injection layers (EIL), or regardless of the number or thickness of hole blocking layers (HBL), or the second Regardless of the number or thickness of the electrodes 204, or the number or thickness of the first emission layers (EML) 214, or the number or thickness of the second emission layers (EML) 224, or 3 Regardless of the number or thickness of the emission layers (EML) 234, or regardless of the number or thickness of all organic layers between the substrate 201 and the first emission layer (EML) 214, or the first emission layer ( Regardless of the number or thickness of all organic layers between the EML) 214 and the second emission layer (EML) 224, or the second emission layer (EML) 224 and the third emission layer (EML) 234 Regardless of the number or thickness of all organic layers between, or regardless of the thickness of all organic layers between the third emission layer (EML) 234 and the second electrode 204, from the first electrode 202 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. Alternatively, 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 reflective surface of the first electrode 202. Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 204, 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. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 204, 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 reflective surface of the first electrode 202.

The structure shown in FIG. 16 shows an example of the present invention, and may 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 illustrating a light emission position of an organic light emitting diode according to a fifth exemplary embodiment of the present invention.

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

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

Accordingly, the emission position of the first emission layer (EML) 214 is set in the range of 150 Å to 650 Å, so that the emission peak 214E is located in the range of 440 nm to 480 nm. Accordingly, the first emission layer (EML) 214 is allowed to emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the first emission layer (EML) 214 constituting the first emission part 210. In this case, the peak wavelength range of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 214 emits light in the 440 nm to 650 nm emission region.

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

Since the second emission layer (EML) 224 constituting the second emission part 220 is a yellow-green emission layer, the peak wavelength of the emission region of the second emission layer (EML) 224 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, by setting the emission position of the second emission layer (EML) 224 in the range of 1,700 Å to 2,300 Å, the emission peak 224E of the second emission layer (EML) 224 is 510 nm to 580 To be located in nm. Accordingly, the second emission layer (EML) 224 emits light at 510 nm to 580 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 is composed of two layers, a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light in the 540 nm to 650 nm emission region.

Accordingly, as the second emission layer (EML) 224, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 224 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the second emission layer (EML) 224 emits light in the 510 nm to 650 nm region.

In FIG. 17, the second emission layer (EML) 224 does not include an auxiliary emission layer, and the second emission layer (EML) 224 shows a light emission position by taking a yellow-green emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 224 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

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

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

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 234 constituting the third emission part 230. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 234 emits light from 440 nm to 650 nm.

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

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

That is, the maximum emission range of the blue emission layer, 440 nm to 470 nm, and the maximum emission range of the yellow-green emission layer, 530 nm to 570 nm, must be made to emit light. Maximum efficiency can be achieved in the white area. It can be seen that the emission layer can achieve maximum efficiency by setting the emission position of the emission layer of the present invention to correspond to the emission region. In addition, the EPEL structure of the present invention includes the number of at least one first organic layer, 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 third organic layers, and the third organic layer. Thickness, the number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers , Regardless of the thickness of the third emission layer, it can be seen that the emission layer can achieve maximum efficiency by configuring the first emission layer, the second emission layer, and the third emission layer to have a maximum emission 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 light emission intensity. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

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

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

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

As shown in FIG. 18, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is a peak wavelength of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

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

In Table 9 below, a 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 The yellow-green light emitting layer and the third light emitting part are formed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 39%, It can be seen that the green efficiency has increased by 63%. In addition, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 61%.

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

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 10, it can be seen that the efficiency of red, green, blue, and white decreases at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . And, looking at the comparison of Table 8 of the fourth embodiment of the present invention with Table 10 of the fifth embodiment of the present invention, the boundary between the embodiment (minimum position) and the embodiment (maximum position) is green and blue. ) And white (white) efficiency was further improved. Accordingly, according to the fifth exemplary embodiment of the present invention, an organic light emitting display device with 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 further reduced than in the embodiment (maximum position). Accordingly, it can be seen that the panel efficiency decreases when the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in a range of 4,700 Å to 5,400 Å from the first electrode.

The emission position of the first emission layer may be set in a range of 150 Å to 650 Å from the first electrode.

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

The emission position of the third emission layer may be set in a range of 2,400 Å to 3,000 Å from the first electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 device according to a sixth embodiment of the present invention. In describing the present embodiment, descriptions of components that are the same as or corresponding to the previous embodiment will be omitted. In the present embodiment, the emission positions of the emission layers are set from the second electrode, and the emission positions may 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 a first electrode 202 and a second electrode 204, and between the first and second electrodes 202 and 204, and a second light emitting device. A unit 220 and a third light emitting unit 230 are provided.

The location of the first electrode 202 is set to be 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, the emission peak 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 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that 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. It 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 additionally formed under the third hole transport layer HTL 232. A hole blocking layer HBL may be additionally formed on the third emission 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 additionally formed under the third emission layer EML 234. The third hole transport layer (HTL) 232 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 234 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

Regardless of the number or thickness of the third electron transport layers (ETL) 236, regardless of the number or thickness of the third emission layers (EML) 234, or regardless of the number or thickness of the electron injection layers (EIL), Or regardless of the number or thickness of the hole blocking layers (HBL), or regardless of the number or thickness of the second electrodes 204, or between the second electrode 204 and the third emission layer (EML) 234 Regardless of the number or thickness of all organic layers present, the light emission position L3 of the third emission layer EML 234 is set to be located within a range of 2,050 Å to 2,750 Å from the second electrode 204. As such, 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 emission layers, and the thickness of the third emission layer, the third emission layer from the second electrode 204 ( The position L3 of the EML) 234 is set to be located within a 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 additionally formed under the second hole transport layer (HTL) 222. A hole blocking layer HBL may be additionally formed on the second emission layer EML 224. The second electron transport layer (ETL) 226 and the hole blocking layer (HBL) may be configured as a single layer.

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

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

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

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 ( 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) 224 may be configured identically or differently above and below the 224.

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

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

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

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

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

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

The second emission 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 layer 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 emission layer (EML) 234 and the second emission layer (EML) 224 and the second emission layer (EML) 224 may be referred to as organic layers. Accordingly, all organic layers between the third emission layer (EML) 234 and the second emission layer (EML) 224 may be referred to as a third organic layer.

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

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the position L2 of the second emission 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 doing. An auxiliary electrode 203 may be formed on the first electrode 202. However, 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 unit 210 may additionally configure 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 emission layer EML 214. The first electron transport layer (ETL) 216 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 214. The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 214 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

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

Regardless of the number or thickness of the first electron transport layers (ETL) 216, regardless of the number or thickness of the first charge generation layers (CGL) 240, or the second hole transport layer (HTL) 222 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 emission layer (EML) 234, regardless of the number or thickness of the second emission layer (EML) 224, or the number or thickness of the first emission layer (EML) 214 Regardless, or regardless of the number or thickness of all organic layers between the second electrode 204 and the third emission layer (EML) 234, or the second emission layer (EML) 224 and the third emission 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 emission layer (EML) 214 and the second emission layer (EML) 224 Without, the emission position L1 of the first emission 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, the number of the at least one 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 third Regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, The position L1 of the first emission layer EML 214 may be set to be located within a range of 4,450 Å to 5,000 Å.

Further, 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 emission layer (EML) 214 and the first emission layer (EML) 214 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 202 and the first emission 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, or regardless of the number or thickness of electron blocking layers (EBL), or a hole injection layer Regardless of the number or thickness of (HIL), regardless of the number or thickness of the third emission layer (EML) 234, or regardless of the number or thickness of the second emission layer (EML) 224, or the first Regardless of the number or thickness of the emission layers (EML) 214, or regardless of the number or thickness of all organic layers between the second electrode 204 and the third emission layer (EML) 234, or the second emission layer Regardless of the number or thickness of all organic layers between the (EML) 224 and the third emission layer (EML) 234, or the first emission layer (EML) 214 and the second emission layer (EML) 224 ), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first electrode 202 and the first emission layer (EML) 214, the first electrode 202 The position L0 of) may be set to be located within a range of 4,700 Å to 5,400 Å from the second electrode 204.

Accordingly, accordingly, the number of the at least one fourth organic layer, 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 second organic layers, 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 emission layer, the thickness of the third emission layer, the number of the second emission layer, the thickness of the second emission layer, the number of the first emission layer, the second emission layer 1 The position L0 of the first electrode 202 from the second electrode 204 may be set to be located within a range of 4,700 Å to 5,400 Å, regardless of the thickness of the emission layer.

Here, the light emission position L1 of the first emission layer EML 214 may be set to be located within a range of 4,450 Å to 5,000 Å from the second electrode 204. In addition, the position L0 of the first electrode 202 may be set to be located within a range of 4,700 Å to 5,400 Å from the second electrode 204. When the light emission position L1 of the first emission 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) can be set to be located in the range of 5,050Å to 5,400Å.

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

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

20 is a diagram illustrating a light emission position of an organic light emitting diode 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 emission positions of the emission layers constituting the light emitting unit from the second electrode 204, and may be referred to as a contour map. Here, except for the first electrode 202 and the second electrode 204, when the EPEL structure of the present invention is applied, the emission positions of the emission layers at the emission peak are shown. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown. In FIG. 20, the emission positions of the emission layers excluding 1,000 Å, which is the thickness of the second electrode 204, are shown, and the thickness of the second electrode 204 does not limit the content of the present invention.

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

Therefore, by setting the emission position of the third emission layer (EML) 234 in the range of 2,050Å to 2,750Å, the emission peak 234E of the third emission layer (EML) 234 is 440nm to 480 To be located in nm. Accordingly, the third emission layer (EML) 234 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency. As described above, in FIG. 20, the emission position of the third emission 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 emission position of the third emission layer (EML) 234 may range from 2,050 Å to 2,750 Å from the second electrode 204. The same may be applied to the light emission position of the second emission layer (EML) 224 and the emission position of the first emission layer (EML) 214.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 234 constituting the third emission part 230. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 234 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 234 emits light from 440 nm to 650 nm.

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

Since the second emission layer (EML) 224 constituting the second emission part 220 is a yellow-green emission layer, the peak wavelength of the emission region of the second emission layer (EML) 224 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Therefore, by setting the light emission position of the second emission layer (EML) 224 in the range of 2,850 Å to 3,550 Å, the emission peak 224E of the second emission layer (EML) 224 is 510 nm to 580 To be located in nm. Accordingly, the second emission layer (EML) 224 emits light at 510 nm to 580 nm, thereby achieving maximum efficiency.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 is composed of two layers, a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light at 510 nm to 650 nm, which is an emission region.

In addition, the second emission layer (EML) 224 of the second emission unit 220 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 224 emits light in the 540 nm to 650 nm emission region.

Accordingly, as the second emission layer (EML) 224, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the second emission layer (EML) 224 is 510 It can range from nm to 650 nm.

In FIG. 20, the second emission layer (EML) 224 does not include an auxiliary emission layer, and the second emission layer (EML) 224 shows a light emission position by taking a yellow-green emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 224 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

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

Accordingly, the emission position of the first emission 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. Accordingly, the first emission layer (EML) 214 is allowed to emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the first emission layer (EML) 214 constituting the first emission part 210. In this case, the peak wavelength range of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 214 emits light in the 440 nm to 650 nm emission region.

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

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

That is, the maximum emission range of the blue emission layer, 440 nm to 470 nm, and the maximum emission range of the yellow-green emission layer, 530 nm to 570 nm, must be made to emit light. Maximum efficiency can be achieved in the white area. It can be seen that the emission layer can achieve maximum efficiency by setting the emission position of the emission layer of the present invention to correspond to the emission region. In addition, the EPEL structure of the present invention includes the number of at least one first organic layer, 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 third organic layers, and the third organic layer. Thickness, the number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers , Regardless of the thickness of the third emission layer, it can be seen that the emission layer can achieve maximum efficiency by configuring the first emission layer, the second emission layer, and the third emission layer to have a maximum emission 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 range of light, and the vertical axis represents the light emission intensity. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

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

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

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

As shown in FIG. 21, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimal position, the following is. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is a peak wavelength of red light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 11 below. Assuming that the efficiency of the comparative example is 100%, it shows the efficiency of the sixth example of the present invention.

In Table 11 below, a 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 The yellow-green light emitting layer and the third light emitting part are formed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 39%, It can be seen that the green efficiency has increased by 63%. In addition, it can be seen that the blue efficiency increased by 47%, and the white efficiency increased by 61%.

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

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

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 12, it can be seen that the efficiency of red, green, blue, and white decreases 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 is further 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 EPEL (Emission Position of Emitting Layers) structure of the present invention is out of the optimum 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 in the range of 4,700 Å to 5,400 Å from the second electrode.

The emission position of the third emission layer may be set in a range of 2,050 Å to 2,750 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 2,850 Å to 3,550 Å from the second electrode.

The emission position of the third emission layer may be set in the range of 4,450 Å to 5,000 Å from the first electrode.

The first emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The second emission layer may be formed of one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

The emission area of the first emission layer may be in the range of 440 nm to 650 nm, the emission area of the second emission layer may be in the range of 510 nm to 650 nm, and the emission area of the third emission 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 440 nm to 470 nm, the maximum emission range of the second emission layer is in the range of 530 nm to 570 nm, and the maximum emission range of the third emission layer is in the range of 440 nm to 470 nm. I can.

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 shows the organic light-emitting device according to the fourth, fifth and sixth embodiments of the present invention. I used it.

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 illustrated in an inverted staggered structure, but may be formed in a coplanar structure.

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

The gate electrode 2115 is formed on the substrate 20 and is connected to a gate line (not shown). The gate electrode 2115 is in 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 multilayer made of any one selected 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 by 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. In addition, 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 molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni ), neodymium (Nd) and copper (Cu) may be made of any one selected from the group consisting of 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 an acrylic resin, a polyimide resin, or the like, 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 under the first electrode 202 to reflect light in the direction of the second electrode 204. In addition, an auxiliary electrode may be further formed on the first electrode 202.

The first electrode 202 is electrically connected to the drain electrode 2135 through a contact hole CH in a predetermined region of the protective layer 2140. In FIG. 22, the drain electrode 2135 and the first electrode 202 are shown to be electrically connected, but the source electrode 2133 and the first electrode through a contact hole CH in a predetermined region of the protective layer 2140 It is also possible for 202 to be electrically connected.

The 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 in a boundary region between a plurality of pixels, so that a pixel region is defined by the bank layer 2170.

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

The second electrode 204 is formed on the light emitting part 2180. In addition, 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 moisture from penetrating into the light emitting part 2180. The encapsulation layer 2190 may be formed of a plurality of layers in which different inorganic materials are stacked, or may be formed of 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 or plastic, or may be made of metal. In addition, a color filter 2302 and a black matrix 2303 are disposed on the encapsulation substrate 2301. The light emitted from the light-emitting unit 2180 proceeds toward the encapsulation substrate 2301 to display an image through the color filter 2302.

In addition, the inventors of the present invention invented a top emission type white organic light-emitting device having a new structure in which the luminous efficiency and panel efficiency of the emission layer can be improved, and the 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 placing light-emitting layers including light-emitting layers emitting the same color adjacent to each other. In addition, compared to the organic light emitting display device to which the lower light emitting method is applied, the organic light emitting display device to which the upper light emitting method according to an embodiment of the present invention is applied may have an improved aperture ratio.

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

The white organic light-emitting device 300 illustrated 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 part 330.

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

The white organic light-emitting device 300 of the top emission type of the present invention includes a first light-emitting unit 310, a second light-emitting unit 320, and a first electrode 302 and a second electrode 304 It includes a third light emitting unit 330.

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

The position L0 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. In addition, the emission peak of the emission layer constituting the first light emitting unit 310, the second light emitting unit 320, and the third light emitting unit 330 is positioned at a specific wavelength, and Light emission efficiency can be improved by emitting light. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

A position (L0) of the second electrode 304 is set from the first electrode 302, and a light emission position (L1) of the first light-emitting unit 310 at a position closest to the first electrode 302 ) Is set to be 200Å to 700Å. Alternatively, the light emission position L1 of the first light emitting part 310 is set to be located 200 Å to 700 Å from the reflective surface of the first electrode 302. The first light emitting part 310 may be formed of a yellow-green light emitting layer. It is set to be located within a range of 200 Å to 700 Å from the first electrode 302 regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers. Therefore, the first light-emitting unit 310 achieves maximum luminance by making the emission peak positioned in the yellow-green emission region and emitting light having a wavelength corresponding to the emission peak. To be able to pay. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Here, the peak wavelength may be an emission region.

In addition, the first light-emitting unit 310 may be formed of two layers, a red light-emitting layer and a green light-emitting layer, depending on the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, when the red emission layer and the green emission layer are composed of two layers, the peak wavelength of the emission region may be in the range of 510 nm to 660 nm. Here, the peak wavelength may be an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

In addition, the first light-emitting unit 310 may include two layers of a red light-emitting layer and a yellow-green light-emitting layer according to the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When composed of two layers of the red emission layer and the yellow-green emission layer, the peak wavelength of the emission region may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased.

In addition, according to the characteristics or structure of the device, the first light-emitting unit 310 may be formed of two layers, a yellow light-emitting layer and a red light-emitting layer. Peak wavelengths of the emission regions of the yellow and red emission layers may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

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

The second light-emitting unit 320 may be formed of a blue light-emitting layer. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

Accordingly, the second light-emitting part 320 emits light having a wavelength corresponding to the emission peak by allowing the emission peak of the second light-emitting part 320 to be positioned in the blue light-emitting region. ) To produce 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. The second light emitting part 320 may be formed of one of a red light emitting layer, a green light emitting layer, and a yellow-green light emitting layer as an auxiliary light emitting layer, or a combination thereof. In addition, a peak wavelength of a light-emitting region of the light-emitting layer including the auxiliary light-emitting layer and constituting the second light-emitting unit 320 may range from 440 nm to 650 nm. Here, the peak wavelength may be an emission region.

The light emission 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 first electrode 302. Alternatively, the light emission 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 formed of a blue light emitting layer. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L3 of the third emission unit 330 is 2,400 Å to 3,100 Å from the first electrode 302. Set to be within the range of. Alternatively, the light emission 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. Accordingly, the emission peak of the third light-emitting unit 330 is positioned in a blue light-emitting region so that the third light-emitting unit 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. The third light emitting part 330 may be formed of one of a red light emitting layer, a green light emitting layer, a yellow-green light emitting layer, or a combination thereof as an auxiliary light emitting layer. In addition, a peak wavelength of the emission region of the emission layer including the auxiliary emission layer and constituting the third emission unit 330 may range from 440 nm to 650 nm. Here, the peak wavelength may be an emission region.

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

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

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

The position of the second electrode 304 is set to be 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, the emission peak of the emission layers constituting the first light-emitting part 310, the second light-emitting part 320, and the third light-emitting part 330 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that 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 doing.

An auxiliary electrode 303 may be formed on the first electrode 302. The auxiliary electrode 303 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 emission 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 emission layer EML 314. The first hole transport layer (HTL) 312 and the electron blocking layer (EBL) may be configured as a single layer.

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

In addition, the first emission layer (EML) 314 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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) 314 may be configured above or below. 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) 314 may be configured identically or differently above and below the 314.

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

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, the peak wavelength of the emission region 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

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

In addition, the first emission layer (EML) 314 may include two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In this case, the peak wavelength of the emission region of the first emission layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The first emission layer (EML) 314 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or yellow- When composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength of the emission region of the first emission layer (EML) 314 is 510 nm to 650 It can be in the range of nm. Here, the peak wavelength may be an emission 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 emission layer (EML) 314 and the auxiliary electrode 303 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 302 and the first emission layer (EML) 314 may be referred to as a first organic layer.

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

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 additionally formed under the second hole transport layer (HTL) 322.

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

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

The second emission layer (EML) 324 includes a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

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

Regardless of the number or thickness of the first electron transport layers (ETL) 316 or the number or thickness of the second hole transport layers (HTL) 322, or the first charge generation layer (CGL) 340 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 emission layer (EML) 314, or regardless of the number or thickness of all organic layers between the first electrode 302 and the first emission layer (EML) 314, or the Regardless of the number or thickness of all organic layers between the first emission layer (EML) 314 and the second emission layer (EML) 324, the emission position (L2) of the second emission layer (EML) 324 is It is set to be located within a range of 1,200 Å to 1,800 Å from the first electrode 302. Alternatively, the emission position L2 of the second emission layer EML 324 is set to be located 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The position L2 of the second emission layer EML 324 from the first electrode 302 may be set to be located within a range of 1,200 Å to 1,800 Å. Alternatively, regardless of the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The position L2 of the second emission layer EML 324 from the reflective surface of the first electrode 302 may be set to be located 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 additionally 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 emission 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 additionally formed under the third emission layer EML 334. The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 334 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

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

In addition, all layers such as the third emission 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 emission layer (EML) 334 and the second electrode 304, the second electrode 304, and the third emission layer (EML) 334 may be referred to as organic layers. Accordingly, all organic layers disposed between the third emission 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 electron injection layers (EIL), or regardless of the number or thickness of hole blocking layers (HBL), or the second Regardless of the number or thickness of the electrodes 304, regardless of the number or thickness of the third emission layer (EML) 334, or between the substrate 301 and the first emission layer (EML) 314 Regardless of the number or thickness of organic layers, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 314 and the second emission layer (EML) 324, or the second emission layer (EML) Regardless of the number or thickness of all organic layers between 324 and the third emission layer (EML) 334, or all organic layers between the third emission layer (EML) 334 and the second electrode 304 The position L0 of the second electrode 304 from the first electrode 302 may be set to be located within a range of 4,700 Å to 5,400 Å, regardless of the thickness of. 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.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 304, 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. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 304, 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.

The structure shown in FIG. 24 shows an example of the present invention, and may be selectively configured according to a structure or characteristic of a white organic light-emitting device, but is not limited thereto.

25 is a diagram illustrating a light emitting position of an organic light emitting diode 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 emission positions of the emission layers constituting the light emitting part from the first electrode 302, which may be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, when the EPEL structure of the present invention is applied, the emission positions of the emission layers at the emission peak are shown. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown.

Since the first emission layer (EML) 314 constituting the first emission part 310 is a yellow-green emission layer, the peak wavelength of the emission region of the first emission layer (EML) 314 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, the emission position of the first emission 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, maximum efficiency can be achieved by allowing light to emit light from 510 nm to 580 nm in the first emission layer (EML) 314.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light at 540 nm to 650 nm.

Accordingly, as the first emission layer (EML) 314, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the first emission layer (EML) 314 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm region.

In FIG. 25, the first emission layer (EML) 314 does not include an auxiliary emission layer, and the first emission layer (EML) 314 is a yellow-green emission layer as an example to indicate the emission position. Accordingly, the peak wavelength range of the emission region of the first emission layer (EML) 314 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

Since the second emission layer (EML) 324 constituting the second emission part 320 is a blue emission layer, the peak wavelength range of the emission region of the second emission layer (EML) 324 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the light emission position of the second emission layer (EML) 324 in the range of 1,200 Å to 1,800 Å, the emission peak 324E of the second emission layer (EML) 324 is 440 nm to 480 To be located in nm. Accordingly, the second emission layer (EML) 324 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the second emission layer (EML) 324 constituting the second emission part 320. In this case, the peak wavelength range of the emission region of the second emission layer (EML) 324 may be in the range of 440 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 324 emits light in the 440 nm to 650 nm emission region.

In FIG. 25, the second emission layer (EML) 324 does not include an auxiliary emission layer, and the second emission layer (EML) 324 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 324 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the third emission layer (EML) 334 constituting the third emission part 330 is a blue emission layer, the peak wavelength range of the emission region of the third emission layer (EML) 334 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Accordingly, by setting the emission position of the third emission layer (EML) 334 in the range of 2,400 Å to 3,100 Å, the emission peak 334E of the third emission layer EML 334 is 440 nm to 480 To be located in nm. Accordingly, the third emission layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 334 constituting the third emission part 330. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 334 emits light from 440 nm to 650 nm.

In FIG. 25, the third emission layer (EML) 334 does not include an auxiliary emission layer, and the third emission layer (EML) 334 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 334 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

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

26 is a diagram showing an EL spectrum according to the seventh embodiment of the present invention.

In FIG. 26, the horizontal axis represents the wavelength region of light, and the vertical axis represents the intensity of light emission. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 26, the embodiment (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L1 of the first emission layer EML 314 is in the range of 200Å to 700Å from the first electrode 302, the minimum position is set to 200Å.

The embodiment (maximum position) is a portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the light emission position L1 of the first emission layer EML 314 is in the range of 200Å to 700Å from the first electrode 202, the maximum position is set to 700Å.

The embodiment (optimal position) is a part set as the light emitting position in the seventh embodiment of the present invention. For example, when the light emission position L1 of the first emission layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the emission position in the embodiment is set in the range of 200 Å to 700 Å. .

As shown in FIG. 26, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, compared with the optimum position, it is as follows. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 13 below. When the efficiency of the comparative example is 100%, it shows the efficiency of the seventh example of the present invention.

Table 13 below compares the efficiencies of Comparative Examples and Examples of the present invention. 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 first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( The yellow-green) light emitting layer and the third light emitting part are composed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 77%, and the green efficiency is 64. It can be seen that it has increased by about %. In addition, it can be seen that the blue efficiency increased by 51%, and the white efficiency increased by 68%.

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) 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 example (minimum position) and the example (maximum position) when the efficiency of the example (optimum position) is 100%.

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 14, it can be seen that the efficiency of red, green, blue, and white decreases at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . In addition, it can be seen that the efficiency of the embodiment (minimum position) in red, green, blue, and white decreases more than the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the optimum position of the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is deviated.

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 emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the first emission layer may be set in a range of 200 Å to 700 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 1,200 Å to 1,800 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 2,400 Å to 3,100 Å from the first electrode.

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 diode according to an eighth embodiment of the present invention. In describing the present embodiment, descriptions of components that are the same as or corresponding to the previous embodiment will be omitted.

The white organic light emitting device 300 shown in FIG. 27 includes a first light emitting unit 310 between a first electrode 302 and a second electrode 304, and between the first and second electrodes 302 and 304, and a second light emitting device. A portion 320 and a third light emitting portion 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, the emission peak of the emission layers constituting the first light-emitting part 310, the second light-emitting part 320, and the third light-emitting part 330 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that specific wavelength. That is, the first light emitting part 310, the second light emitting part 320, and the third light emitting part 330 are EPELs having a maximum light emission 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) structure. Two of the first emission layer, the second emission layer, and the third emission layer include an emission layer emitting the same color, thereby providing a white organic light emitting device capable of further improving luminous efficiency. The emission layer emitting the same color may be referred to as a light emitting layer including at least one emission 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 doing.

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 emission layer EML 314.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 314.

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

In addition, the first emission layer (EML) 314 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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) 314 may be configured above or below. 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) 314 may be configured identically or differently above and below the 314.

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

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Accordingly, the peak wavelength of the emission region 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

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

In addition, the first emission layer (EML) 314 may include two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In this case, the peak wavelength of the emission region of the first emission layer (EML) 314 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The first emission layer (EML) 314 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or yellow- When composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength of the emission region of the first emission layer (EML) 314 is 510 nm to 650 It can be in the range of nm. Here, the peak wavelength may be an emission 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 emission layer (EML) 314 and the auxiliary electrode 303 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 302 and the first emission layer (EML) 314 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 312, regardless of the number or thickness of the auxiliary electrodes 303, or regardless of the number or thickness of the electron blocking layers (EBL), or a 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 emission layer (EML) 314, the first emission layer (EML) 314 The light emission position L1 of is set to be located within a range of 200 Å to 700 Å from the first electrode 302. Alternatively, the emission position L1 of the first emission 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.

Accordingly, the position (L1) of the first emission layer (EML) 314 from the first electrode 302 is in the range of 200 Å to 700 Å, regardless of the number of the at least one first organic layer and the thickness of the first organic layer. Can be set to be located within. Alternatively, regardless of the number of the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer (EML) 314 is 200 Å from the reflective surface of the first electrode 302 It can be set to be located in the range of to 700Å.

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 additionally formed under the second hole transport layer (HTL) 322.

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

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

The second emission layer (EML) 324 includes a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The auxiliary emission layer may be composed of one of a yellow-green emission layer, a red emission layer, a green emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved. When configuring the second emission layer (EML) 324 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is the second emission layer (EML). ) It is also possible to configure it above or below 324. In addition, as the auxiliary emission layer, a yellow-green emission layer, a red emission layer, or a green emission layer is configured identically or differently above and below the second emission layer (EML) 324. It is also possible. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

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

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

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

Regardless of the number or thickness of the first electron transport layers (ETL) 316 or the number or thickness of the second hole transport layers (HTL) 322, or the first charge generation layer (CGL) 340 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 emission layer (EML) 314, or regardless of the number or thickness of all organic layers between the first electrode 302 and the first emission layer (EML) 314, or the Regardless of the number or thickness of all organic layers between the first emission layer (EML) 314 and the second emission layer (EML) 324, the emission position (L2) of the second emission layer (EML) 324 is The first electrode 302 is set to be positioned within a range of 1,250 Å to 1,750 Å. Alternatively, the emission position L2 of the second emission layer EML 324 is set to be located 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The position L2 of the second emission layer EML 324 from the first electrode 302 may be set to be located within a range of 1,250 Å to 1,750 Å. Alternatively, regardless of the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The position L2 of the second emission layer EML 324 from the reflective surface of the first electrode 202 may be set to be located 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 additionally 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 emission 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 additionally formed under the third emission layer EML 334. The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 334 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The auxiliary emission layer may be composed of one of a yellow-green emission layer, a red emission layer, a green emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved.

When configuring the third emission layer (EML) 334 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is a third emission layer (EML) ( It is also possible to configure above or below 334). In addition, as the auxiliary emission layer, a yellow-green or red emission layer or a green emission layer may be configured identically or differently above and below the third emission layer (EML) 334. It is possible. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

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

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

Regardless of the number or thickness of the second electron transport layers (ETL) 326, regardless of the number or thickness of the second charge generation layers (CGL) 350, or the third hole transport layer (HTL) 332 Regardless of the number or thickness of, or regardless of the number or thickness of the second emission layers (EML) 324, or regardless of the number or thickness of the first emission layers (EML) 314, or the first electrode 302 ) And the first emission layer (EML) 314, regardless of the number or thickness of all organic layers, or between the first emission layer (EML) 314 and the second emission layer (EML) 324 Regardless of the number or thickness of the organic layers, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 324 and the third emission layer (EML) 334, the third emission layer (EML) ( The light emission position L3 of 334 is set to be located within a range of 2,500 Å to 3,000 Å from the first electrode 302. Alternatively, the emission position L3 of the third emission layer EML 334 is set to be located within a range of 2,500 Å to 3,000 Å from the reflective surface of the first electrode 302.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the first The position (L3) of the third emission layer (EML) 334 from the first electrode 302 regardless of the number of emission layers, the thickness of the first emission layer, the number of the second emission layers, and the thickness of the second emission layer May be set to be located in the range of 2,500Å to 3,000Å. Alternatively, at least one 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 third organic layers, the thickness of the third organic layer, the first The position of the third emission layer (EML) 334 from the reflective surface of the first electrode 302 regardless of the number of emission layers, the thickness of the first emission layer, the number of the second emission layers, and the thickness of the second emission layer (L3) may be set to be located in the range of 2,500Å to 3,000Å.

In addition, all layers such as the third emission 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 emission layer (EML) 334 and the second electrode 304, the second electrode 304, and the third emission layer (EML) 334 may be referred to as organic layers. Accordingly, all organic layers disposed between the third emission 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 electron injection layers (EIL), or regardless of the number or thickness of hole blocking layers (HBL), or the second Regardless of the number or thickness of the electrodes 304, regardless of the number or thickness of the third emission layer (EML) 334, or between the substrate 301 and the first emission layer (EML) 314 Regardless of the number or thickness of organic layers, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 314 and the second emission layer (EML) 324, or the second emission layer (EML) Regardless of the number or thickness of all organic layers between 324 and the third emission layer (EML) 334, or all organic layers between the third emission layer (EML) 334 and the second electrode 304 The position L0 of the second electrode 304 from the first electrode 302 may be set to be located within a range of 4,700 Å to 5,400 Å, regardless of the thickness of. 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.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 304, 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. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 304, 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.

The structure shown in FIG. 27 shows an example of the present invention, and may be selectively configured according to a structure or characteristic of a white organic light-emitting device, but is not limited thereto.

28 is a diagram illustrating a light emission position of an organic light emitting diode 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 emission positions of the emission layers constituting the light emitting unit from the first electrode 302, and may be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, when the EPEL structure of the present invention is applied, the emission positions of the emission layers at the emission peak are shown. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown.

Since the first emission layer (EML) 314 constituting the first emission part 310 is a yellow-green emission layer, the peak wavelength of the emission region of the first emission layer (EML) 314 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, the emission position of the first emission 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, maximum efficiency can be achieved by allowing light to emit light from 510 nm to 580 nm in the first emission layer (EML) 314.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light at 540 nm to 650 nm.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

Accordingly, as the first emission layer (EML) 314, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the first emission layer (EML) 314 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm region.

In FIG. 28, the first emission layer (EML) 314 does not include an auxiliary emission layer, and the first emission layer (EML) 314 shows a light emitting position by taking a yellow-green emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 314 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

Since the second emission layer (EML) 324 constituting the second emission part 320 is a blue emission layer, the peak wavelength range of the emission region of the second emission layer (EML) 324 May be in the range of 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the light emission position of the second emission layer (EML) 324 in the range of 1,250 Å to 1,750 Å, the emission peak 324E of the second emission layer (EML) 324 is 440 nm to 480 To be located in nm. Accordingly, the second emission layer (EML) 324 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the second emission layer (EML) 324 constituting the second emission part 320. In this case, the peak wavelength range of the emission region of the second emission layer (EML) 324 may be in the range of 440 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 324 emits light in the 440 nm to 650 nm emission region.

In FIG. 28, the second emission layer (EML) 324 does not include an auxiliary emission layer, and the second emission layer (EML) 324 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 324 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the third emission layer (EML) 334 constituting the third emission part 330 is a blue emission layer, the peak wavelength range of the emission region of the third emission layer (EML) 334 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Accordingly, the emission position of the third emission layer (EML) 334 is set in the range of 2,500 Å to 3,000 Å, so that the emission peak 334E of the third emission layer EML 334 is 440 nm to 480 nm. To be located in nm. Accordingly, the third emission layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 334 constituting the third emission part 330. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 334 emits light from 440 nm to 650 nm.

In FIG. 28, the third emission layer (EML) 334 does not include an auxiliary emission layer, and the third emission layer (EML) 334 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 334 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

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

29 is a diagram showing an EL spectrum according to the eighth embodiment of the present invention.

In FIG. 29, the embodiment (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L1 of the first emission layer EML 314 is in the range of 200Å to 700Å from the first electrode 302, the minimum position is set to 200Å.

The embodiment (maximum position) is a portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the light emission position L1 of the first emission layer EML 314 is in the range of 200Å to 700Å from the first electrode 302, the maximum position is set to 700Å.

The embodiment (optimum position) is a part set as the light emission position in the eighth embodiment of the present invention. For example, when the light emission position L1 of the first emission layer (EML) 314 is in the range of 200 Å to 700 Å from the first electrode 302, the emission position in the embodiment is set in the range of 200 Å to 700 Å. .

As shown in FIG. 29, in the case of deviating from the minimum position of the emission position in the Emission Position of Emitting Layers (EPEL) structure of the present invention, compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity decreases in the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 15 below. Assuming that the efficiency of the comparative example is 100%, it shows the efficiency of the eighth example of the present invention.

Table 15 below compares the efficiencies of Comparative Examples and Examples of the present invention. 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 first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( The yellow-green) light emitting layer and the third light emitting part are composed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 77%, and the green efficiency is 64. It can be seen that it has increased by about %. In addition, it can be seen that the blue efficiency increased by 51%, and the white efficiency increased by 68%.

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 16 below.

Table 16 below shows the efficiency of the example (minimum position) and the example (maximum position) when the efficiency of the example (optimum position) is 100%.

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 16, it can be seen that the efficiency of red, green, blue, and white decreases at the boundary between the embodiment (minimum position) and the embodiment (maximum position). . And, looking at the comparison between Table 14 of the seventh embodiment of the present invention and Table 16 of the eighth embodiment of the present invention, the boundary between the embodiment (minimum position) and the embodiment (maximum position) is green and blue. ) And white (white) efficiency was further improved. Accordingly, according to the eighth embodiment of the present invention, an organic light emitting display device having improved efficiency can be provided. In addition, it can be seen that the efficiency of the embodiment (minimum position) in red, green, blue, and white decreases more than the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the optimum position of the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is deviated.

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 emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the first emission layer may be set in a range of 200 Å to 700 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 1,250 Å to 1,750 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 2,500 Å to 3,000 Å from the first electrode.

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 components that are the same as or corresponding to the previous embodiment will be omitted. In the present embodiment, the emission positions of the emission layers are set from the second electrode, and the emission positions may be set from the second electrode according to device design.

The white organic light emitting device 300 illustrated in FIG. 30 includes a first light emitting unit 310 between a first electrode 302 and a second electrode 304, and between the first and second electrodes 302 and 304, and a second light emitting device. A portion 320 and a third light emitting portion 330 are provided. The position of the second electrode 304 is set to be 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, the emission peak of the emission layers constituting the first light-emitting part 310, the second light-emitting part 320, and the third light-emitting part 330 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that specific wavelength. In addition, the first emission part, the second emission part, and the third emission part have a maximum emission range in the emission regions of the first emission layer, the second emission layer, and the third emission layer (Emission Position of Emitting Layers). It has a structure. In addition, in this embodiment, two emission layers of the first emission layer, the second emission layer, and the third emission layer include an emission layer emitting the same color, thereby providing a white organic light emitting device capable of further improving luminous efficiency. do. The emission layer emitting the same color may be referred to as a light emitting layer including at least one emission 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 additionally formed under the third hole transport layer HTL 332. A hole blocking layer HBL may be additionally formed on the third emission 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 additionally formed under the third emission layer EML 334. The third hole transport layer (HTL) 332 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 334 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

All layers such as the third electron transport layer (ETL) 336, the third emission 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 emission layer (EML) 334, and the second electrode 304 and the third emission layer (EML) 334 may be referred to as organic layers. . Accordingly, all organic layers positioned between the second electrode 304 and the third emission 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 emission layer (EML) 334, or regardless of the number or thickness of electron injection layers (EIL), Alternatively, regardless of the number or thickness of the hole blocking layers (HBL), regardless of the number or thickness of the second electrodes 304, or between the second electrode 304 and the third emission layer (EML) 334 Regardless of the number or thickness of all organic layers, the emission position L3 of the third emission layer EML 334 is set to be located within a range of 2,050 Å to 2,750 Å from the second electrode 304. Accordingly, the third emission layer (EML) from the second electrode 304 is irrespective of the number of at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third emission layer, and the thickness of the third emission layer. The position L3 of 334 may be set to be located within a 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 additionally formed under the second hole transport layer (HTL) 322. A hole blocking layer (HBL) may be additionally formed on the second emission layer (EML) 324. have. The second electron transport layer (ETL) 326 and the hole blocking layer (HBL) may be configured as a single layer.

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

The second emission layer (EML) 324 includes a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

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

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

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

The second emission layer (EML) 324, the second electron transport layer (ETL) 326, the second charge generation layer (CGL) 250, the third hole transport layer (HTL) 332, hole blocking All layers, such as the layer 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 emission layer (EML) 334 and the second emission layer (EML) 324 and the second emission layer (EML) 324 may be referred to as an organic layer. Accordingly, all organic layers between the third emission layer (EML) 334 and the second emission layer (EML) 324 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layers (HTL) 332, or regardless of the number or thickness of the second electron transport layers (ETL) 326, or the second charge generation layer (CGL) 350 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 emission layers (EML) 334, regardless of the number or thickness of the second emission layers (EML) 324, or the second electrode 304 and the third emission layer (EML) Regardless of the number or thickness of all organic layers between) 334, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 324 and the third emission layer (EML) 334, The light emission position L2 of the second emission layer EML 324 is set to be located within a range of 3,350 Å to 3,950 Å from the second electrode 304. Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the position L2 of the second emission 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 doing.

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 emission 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 emission layer EML 314. The first hole transport layer (HTL) 312 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 314 is formed of a yellow-green emission layer. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved. In addition, when the red emission layer and the green emission layer are formed of two layers, the peak wavelength of the emission region may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In addition, a peak wavelength range of a light emitting layer including a red light, which is an auxiliary light emitting layer to a yellow-green light emitting layer, may range from 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

In addition, according to the characteristics or structure of the device, the first light-emitting unit 310 may be formed of two layers, a yellow light-emitting layer and a red light-emitting layer. Peak wavelengths of the emission regions of the yellow and red emission layers may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

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

The first emission layer (EML) 314, the first electron transport layer (ETL) 316, the first charge generation layer (CGL) 340, the second hole transport layer 322, the hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL), and the like may be referred to as organic layers. All organic layers between the first emission layer (EML) 314 and the second emission layer (EML) 324 and the first emission layer (EML) 314 may be referred to as an organic layer. Accordingly, all organic layers between the first emission layer (EML) 314 and the second emission 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 the hole transport layers (HTL) 322, or regardless of the number or thickness of the first charge generation layers (CGL) 340, or regardless of the number or thickness of the hole blocking layers (HBL), or Regardless of the number or thickness of electron blocking layers (EBL), or the number or thickness of hole injection layers (HIL), or regardless of the number or thickness of the third emission layer (EML) 334, or the second emission layer Regardless of the number or thickness of (EML) 324, or regardless of the number or thickness of the first emission layer (EML) 314, or the second electrode 304 and the third emission layer (EML) 334 Regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 324 and the third emission layer (EML) 334, or the first Regardless of the number or thickness of all organic layers between the emission layer (EML) 314 and the second emission layer (EML) 324, the emission position (L1) of the first emission layer (EML) 314 is It is set to be located within the range of 4,450 Å to 4,950 Å from the electrode 304.

Accordingly, the number of the at least one 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 third Regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer, The position L1 of the first emission layer EML 314 may be set to be located 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 emission layer (EML) 314 and the auxiliary electrode 303 may be referred to as an organic layer. Accordingly, all organic layers between the first electrode 302 and the first emission layer (EML) 314 may be referred to as a first organic layer.

Regardless of the number or thickness of the first hole transport layers (HTL) 312, regardless of the number or thickness of the auxiliary electrodes 303, or regardless of the number or thickness of the electron blocking layers (EBL), or a hole injection layer Regardless of the number or thickness of (HIL), or regardless of the number or thickness of the third emission layer (EML) 334, or regardless of the number or thickness of the second emission layer (EML) 324, or the first Regardless of the number or thickness of emission layers (EML) 314, or regardless of the number or thickness of all organic layers between the second electrode 304 and the third emission layer (EML) 334, or the second emission layer Regardless of the number or thickness of all organic layers between the (EML) 324 and the third emission layer (EML) 334, or the first emission layer (EML) 314 and the second emission layer (EML) 324 ), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first electrode 302 and the first emission layer (EML) 314, the second electrode 304 ), the position L0 of the first electrode 302 may be set to be located within a range of 4,700 Å to 5,400 Å.

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the number of the second emission layer, the thickness of the second emission layer, the number of the first emission layer, the first emission layer The position L0 of the first electrode 302 from the second electrode 304 may be set to be located within a range of 4,700 Å to 5,400 Å, regardless of the thickness of.

Here, the light emission position L1 of the first emission layer EML 314 may be set to be located within a range of 4,450 Å to 4,950 Å from the second electrode 304. In addition, the position L0 of the first electrode 302 may be set to be located within a range of 4,700 Å to 5,400 Å from the second electrode 304. When the light emission position L1 of the first emission 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) can be set to be located in the range of 5,000 Å to 5,400 Å.

Accordingly, the present invention provides at least one of the number of 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 third organic layers, the thickness of the third organic layer, The number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the Regardless of the thickness of the third emission layer, the position of the first electrode 302 and the position of the emission layers from the second electrode 304 may be set.

The structure shown in FIG. 30 shows an example of the present invention, and may 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 emission position of an organic light emitting diode 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 emission positions of the emission layers constituting the light emitting unit from the first electrode 302, and may be referred to as a contour map. Here, except for the first electrode 302 and the second electrode 304, when the EPEL structure of the present invention is applied, the emission positions of the emission layers at the emission peak are shown. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown. In FIG. 31, the emission positions of the emission layers are shown except for 1,000 Å, which is the thickness of the second electrode 304, and the thickness of the second electrode 304 does not limit the content of the present invention.

Since the third emission layer (EML) 334 constituting the third emission part 330 is a blue emission layer, the peak wavelength range of the emission region of the third emission layer (EML) 334 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer. As described above, in FIG. 31, the emission position of the third emission 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 emission position of the third emission layer (EML) 334 may range from 2,050 Å to 2,750 Å from the second electrode 304. The same may be applied to the light emission position of the second emission layer (EML) 324 and the emission position of the first emission layer (EML) 314.

Accordingly, by setting the emission position of the third emission layer (EML) 334 in the range of 2,050Å to 2,750Å, the emission peak 334E of the third emission layer (EML) 334 is 440 nm to 480 To be located in nm. Accordingly, the third emission layer (EML) 334 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 334 constituting the third emission part 330. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 334 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 334 emits light from 440 nm to 650 nm.

In FIG. 31, the third emission layer (EML) 334 does not include an auxiliary emission layer, and the third emission layer (EML) 334 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 334 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the second emission layer (EML) 324 constituting the second emission part 320 is a blue emission layer, the peak wavelength range of the emission region of the second emission layer (EML) 324 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Accordingly, the emission position of the second emission layer (EML) 324 is set in the range of 3,350 Å to 3,950 Å, and the emission peak 324E of the second emission layer (EML) 324 is 440 nm to 480 nm. To be located in nm. Accordingly, the second emission layer (EML) 324 emits light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the second emission layer (EML) 324 constituting the second emission part 320. In this case, the peak wavelength range of the emission region of the second emission layer (EML) 324 may be in the range of 440 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 324 emits light in the 440 nm to 650 nm emission region.

In FIG. 31, the second emission layer (EML) 324 does not include an auxiliary emission layer, and the second emission layer (EML) 324 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 324 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the first emission layer (EML) 314 constituting the first emission part 310 is a yellow-green emission layer, the peak wavelength of the emission region of the first emission layer (EML) 314 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, the emission position of the first emission 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, maximum efficiency can be achieved by allowing light to emit light from 510 nm to 580 nm in the first emission layer (EML) 314.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm emission region.

In addition, the first emission layer (EML) 314 of the first emission unit 310 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 314 emits light at 540 nm to 650 nm.

Accordingly, as the first emission layer (EML) 314, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the first emission layer (EML) 314 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the first emission layer (EML) 314 emits light in the 510 nm to 650 nm region.

In FIG. 31, the first emission layer (EML) 314 does not include an auxiliary emission layer, and the first emission layer (EML) 314 is a yellow-green emission layer as an example to indicate the emission position. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 314 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

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

32 is a diagram showing an EL spectrum according to the ninth embodiment of the present invention.

In FIG. 32, the horizontal axis represents the wavelength range of light, and the vertical axis represents the light emission intensity. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 32, the embodiment (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L3 of the third emission layer (EML) 334 is in the range of 2,050Å to 2,750Å from the second electrode 304, the minimum position is set to 2,050Å.

The embodiment (maximum position) is a portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the light emission position L3 of the third emission layer (EML) 334 is in the range of 2,050Å to 2,750Å from the second electrode 304, the maximum position is set to 2,750Å.

The embodiment (optimum position) is a part set as the light emission position in the eighth embodiment of the present invention. For example, when the light emission position L3 of the third emission layer (EML) 334 is in the range of 2,050Å to 2,750Å from the second electrode 304, the emission position of the embodiment is 2,050Å to 2,750Å. It was set as a range.

As shown in FIG. 32, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is. It can be seen that the light emission intensity decreases in the peak wavelength range of blue light from 440 nm to 480 nm, and out of the peak wavelength range of blue light. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 17 below. Assuming that the efficiency of the comparative example is 100%, it shows the efficiency of the ninth example of the present invention.

Table 17 below compares the efficiencies of Comparative Examples and Examples of the present invention. 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 first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( The yellow-green) light emitting layer and the third light emitting part are composed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) 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 it has increased by about %. In addition, it can be seen that the blue efficiency increased by 51%, and the white efficiency increased by 68%.

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 16 below.

Table 18 below shows the efficiency of the example (minimum position) and the example (maximum position) when the efficiency of the example (optimum position) is 100%.

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 18, it can be seen that the efficiency of red, green, blue, and white decreases 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 (maximum position) is further reduced than in the embodiment (minimum position).

Accordingly, it can be seen that the panel efficiency decreases when the optimum position of the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is deviated.

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 emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the third emission layer may be set in a range of 2,050 Å to 2,750 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 3,350 Å to 3,950 Å from the second electrode.

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

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 illustrates the organic light-emitting device according to the seventh, eighth, and ninth embodiments of the present invention. I used it. In describing the present embodiment, descriptions of components that are the same as or corresponding to the previous embodiment will be omitted.

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 unit 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 illustrated in an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 30 may be made of glass, metal, or plastic.

The gate electrode 3115 is formed on the substrate 30.

The gate insulating layer 3120 is formed on the gate electrode 3115.

The semiconductor layer 3131 is formed on the gate insulating layer 3120.

The source electrode 3133 and the drain electrode 3135 may be formed on the semiconductor layer 3131.

The 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 is additionally configured under the first electrode 302 to reflect light in the direction of the second electrode 304. In addition, an auxiliary electrode may be further formed on the first electrode 302.

The first electrode 302 is electrically connected to the drain electrode 3135 through a contact hole CH in a predetermined region of the protective layer 3140.

The 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 part, a second light-emitting part, and a second light-emitting part 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 or plastic, or may be made of metal. In addition, a color filter 3302 and a black matrix 3303 are disposed on the encapsulation substrate 3301. The light emitted from the light-emitting unit 3180 proceeds toward the encapsulation substrate 3301 to display an image through the color filter 3302.

In addition, the inventors of the present invention invented a bottom emission type white organic light emitting device having a new structure in which luminous efficiency and panel efficiency of the light emitting layer can be improved and luminance is improved. The inventors of the present invention invented a white organic light-emitting device capable of further improving blue efficiency by placing 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 diode according to a tenth embodiment of the present invention.

The white organic light-emitting device 400 illustrated in FIG. 34 includes first and second electrodes 402 and 404, and a first and second light emitting portions 410 and 410 disposed between the first and second electrodes 402 and 404. It includes 420 and a third light emitting unit 430.

The first electrode 402 is an anode supplying holes. The second electrode 404 is a cathode that supplies electrons. Each of the first electrode 402 and the second electrode 404 may be referred to as an anode or a cathode. The first electrode may be a transmissive electrode, and the second electrode may be a reflective electrode.

The present invention is to improve luminous efficiency and panel efficiency by setting the position of the first electrode from the second electrode and setting the emission positions of the first emission layer, the second emission layer, and the third emission layer. That is, the first emission part, the second emission part, and the third emission part have a maximum emission range in the emission regions of the first emission layer, the second emission layer, and the third emission layer (Emission Position of Emitting Layers). It has a structure. In addition, two of the first emission layer, the second emission layer, and the third emission layer include an emission layer emitting the same color, thereby providing a white organic light-emitting device capable of further improving luminous efficiency. The emission layer emitting the same color may be referred to as a light emitting layer including at least one emission layer emitting the same color.

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 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, the emission peak of the emission layer constituting the first light-emitting unit 410, the second light-emitting unit 420, and the third light-emitting unit 430 is positioned at a specific wavelength, and Light emission efficiency can be improved by emitting light. The emission peak may be referred to as an emission peak of an organic layer constituting the emission parts.

A position (L0) of the first electrode 402 is set from the second electrode 404, and a light emission position (L1) of the third light-emitting unit 430 at a position closest to the second electrode 404 ) Is set to be located in the range of 250Å to 800Å. Alternatively, the light emission 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 be 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. ) And a green light emitting layer, or a combination thereof. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L1 of the third emission unit 430 is 250 Å to 800 Å from the second electrode 404. Be within range. Alternatively, the light emission 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 third light-emitting unit 430 can emit maximum luminance by making the emission peak located in the blue light-emitting region and emitting light having a wavelength corresponding to the emission peak. . The peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, a peak wavelength range of the blue emission layer and the yellow-green emission layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue and red emission layers may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue and green emission layers may be 440 nm to 560 nm. Here, the peak wavelength may be an emission region.

The light emission 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 emission 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 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. ) And a green light emitting layer, or a combination thereof. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L2 of the second emission unit 420 is 1,450 Å to 1,950 Å from the second electrode 404. Set to be within the range of Å. Alternatively, the light emission position L1 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 reflective surface of the second electrode 404.

Accordingly, the second light-emitting unit 420 can emit maximum luminance by making the emission peak positioned in the blue emission region and emitting light having a wavelength corresponding to the emission peak. . The peak wavelength range of the blue light emitting layer may be 440 nm to 480 nm. In addition, a peak wavelength range of the blue emission layer and the yellow-green emission layer may be 440 nm to 580 nm. In addition, the peak wavelength range of the blue and red emission layers may be 440 nm to 650 nm. In addition, the peak wavelength range of the blue and green emission layers may be 440 nm to 560 nm. Here, the peak wavelength may be an emission region.

The light emission 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 emission 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 is 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 be composed of one of a yellow-green) emission layer and a red emission layer, or a combination thereof.

Regardless of at least one of the thickness of the emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, the emission position L3 of the first emission unit 420 is 2,050 Å to 2,600 Å from the second electrode 404. Set to be within the range of Å. Alternatively, the light emission position L3 of the first light emitting part 420 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.

Accordingly, the emission peak is positioned in a yellow-green emission region, a yellow and red emission region, or a red and green emission region, or a yellow-green and red emission region, and the emission peak ( Emitting Peak) is emitted so that the first light-emitting unit 110 emits maximum luminance. The yellow-green light emitting layer may have a peak wavelength range of 510 nm to 580 nm. In addition, a peak wavelength range of the yellow and red emission layers may be 540 nm to 650 nm. In addition, the peak wavelength range of the red and green emission layers may be 510 nm to 650 nm. In addition, a peak wavelength range of the yellow-green and red light-emitting layers may be 510 nm to 650 nm. Here, the peak wavelength may be an emission 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 emission layer, the number of emission layers, the thickness of the organic layer, and the number of organic layers, and the second An EPEL (Emission Position of Emitting Layers) structure in which the emission positions of the emission layers are set from the electrode 404 is applied. In addition, the first light emitting part, the second light emitting part, and the third light emitting part have an Emission Position of Emitting Layers (EPEL) structure having a maximum light emission range in the light emitting regions of the first, second, and third light emitting layers will be.

35 is a diagram illustrating a white organic light emitting diode according to a tenth embodiment of the present invention.

The white organic light-emitting device 400 illustrated 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 part 430.

Each of the first electrode 402 and the second electrode 404 may be referred to as an anode or a cathode.

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

The position of the first electrode 402 is set to be 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, the emission peak of the emission layers constituting the first light-emitting part 410, the second light-emitting part 420, and the third light-emitting part 430 It is possible to improve the efficiency of the light emitting layers by placing is located at a specific wavelength and emitting light of that 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. It 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 436.

A hole injection layer (HIL) may be additionally formed under the third hole transport layer (HTL) 432.

A hole blocking layer HBL may be additionally formed on the third emission layer EML 434. The third electron transport layer (ETL) 436 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer (EBL) may be additionally formed under the third emission layer (EML) 434. The third hole transport layer (HTL) 432 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 434 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

The auxiliary emission layer may be composed of one of a yellow-green emission layer, a red emission layer, a green emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved. When configuring the third emission layer (EML) 434 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is the third emission layer (EML) It is also possible to configure above or below 434. In addition, as the auxiliary emission layer, a yellow-green or red emission layer or a green emission layer may be configured identically or differently above and below the third emission layer (EML) 134. have. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

When the auxiliary emission layer is formed on the third emission layer (EML) 434, the peak wavelength of the emission region of the third emission layer (EML) 434 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission region.

All layers such as the third electron transport layer (ETL) 436, the third emission 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 emission layer (EML) 434 and the third emission layer (EML) 434 may be referred to as an organic layer. Accordingly, all organic layers positioned between the second electrode 404 and the third emission layer (EML) 434 may be referred to as a fourth organic layer.

Regardless of the number or thickness of the third electron transport layers (ETL) 436, regardless of the number or thickness of the third emission layers (EML) 434, or regardless of the number or thickness of the electron injection layers (EIL), Alternatively, regardless of the number or thickness of the hole blocking layers (HBL), or regardless of the number or thickness of all organic layers between the second electrode 404 and the third emission layer (EML) 434, the third emission layer ( The emission position L1 of the EML) 434 is set to be located within a range of 250 Å to 800 Å from the second electrode 404. Alternatively, the emission position L1 of the third emission 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 the at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third emission layer, and the thickness of the third emission layer, the emission position (L1) of the third emission layer (EML) 434 ) May be set to be located within a range of 250 Å to 800 Å from the second electrode 404. Alternatively, regardless of the number of the at least one fourth organic layer, the thickness of the fourth organic layer, the number of the third emission layer, the thickness of the third emission layer, the emission position (L1) of the third emission layer (EML) 434 ) May be set to be located 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 additionally formed under the second hole transport layer HTL 4122.

A hole blocking layer HBL may be additionally formed on the second emission layer EML 424. The second electron transport layer (ETL) 126 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the second emission layer EML 424. The second hole transport layer (HTL) 422 and the electron blocking layer (EBL) may be configured as a single layer.

The second emission layer (EML) 424 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission 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 brightness.

The auxiliary emission layer may be composed of one of a yellow-green emission layer, a red emission layer, a green emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved. When configuring the second emission layer (EML) 424 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is the first emission layer (EML) ( 114) can be configured above or below. In addition, as the auxiliary emission layer, a yellow-green emission layer, a red emission layer, or a green emission layer may be configured identically or differently above and below the second emission layer (EML) 424. I can. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

When the auxiliary emission layer is formed on the second emission layer (EML) 424, the peak wavelength of the emission region of the second emission layer (EML) 424 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission region.

A second charge generation 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 emission layer (EML) 424, the second electron transport layer (ETL) 426, the second charge generation layer (CGL) 450, the third hole transport layer (HTL) 432, hole blocking All layers, such as the layer 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 emission layer (EML) 434 and the second emission layer (EML) 424 and the second emission layer (EML) 424 may be referred to as an organic layer. Accordingly, all organic layers between the third emission layer (EML) 334 and the second emission layer (EML) 324 may be referred to as a third organic layer.

Regardless of the number or thickness of the third hole transport layers (HTL) 432, regardless of the number or thickness of the second electron transport layers (ETL) 426, or the second charge generation layer (CGL) 450 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 emission layers (EML) 434, regardless of the number or thickness of the second emission layers (EML) 424, or the second electrode 404 and the third emission layer (EML) Regardless of the number or thickness of all organic layers between) 434, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 424 and the third emission layer (EML) 434, The light emission position L2 of the second emission layer EML 424 may be set to be located within a range of 1,450 Å to 1,950 Å from the second electrode 404. Alternatively, the light emission position L2 of the second emission layer EML 424 may be set to be located within a range of 1,450 Å to 1,950 Å from the reflective surface of the second electrode 404.

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the position L2 of the second emission layer EML 424 from the second electrode 404 may be set to be located within a range of 1,450 Å to 1,950 Å. . Alternatively, the number of the at least one 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 emission layer, the thickness of the third emission layer, the second Regardless of the number of emission layers and the thickness of the second emission layer, the position (L2) of the second emission layer (EML) 424 from the reflective surface of the second electrode 404 is positioned 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 doing.

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 emission layer EML 414. The first electron transport layer (ETL) 416 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the first emission layer EML 414. The first hole transport layer (HTL) 412 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 414 is formed of a yellow-green emission layer. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm.

In addition, the first emission layer (EML) 414 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer. 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 ( 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) 414 may be configured identically or differently above and below.

In addition, the peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, peak wavelengths of the emission regions of the yellow and red emission layers of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

In addition, the peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, peak wavelengths of the emission regions of the yellow and red emission layers of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

In addition, the first emission layer (EML) 414 may be formed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In this case, the peak wavelength of the emission region of the first emission layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The first emission layer (EML) 414 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or yellow- When composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength of the emission region of the first emission layer (EML) 414 is 510 nm to 650 It can be in the range of nm. Here, the peak wavelength may be an emission region.

A first charge generation layer (CGL) 440 may be further formed between the first light-emitting part 410 and the second light-emitting part 420. The first charge generation layer (CGL) 440 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL).

The first emission layer (EML) 414, the first electron transport layer (ETL) 416, the first charge generation layer (CGL) 440, the second hole transport layer 422, and a hole blocking layer (HBL) ), electron blocking layer (EBL), hole injection layer (HIL), and the like may be referred to as organic layers. All organic layers between the first emission layer (EML) 414 and the second emission layer (EML) 424 and the first emission layer (EML) 414 may be referred to as an organic layer. Accordingly, all organic layers between the first emission layer (EML) 414 and the second emission 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 the hole transport layers (HTL) 422, or regardless of the number or thickness of the first charge generation layers (CGL) 440, or regardless of the number or thickness of the hole blocking layers (HBL), or Regardless of the number or thickness of the electron blocking layers (EBL), the number or thickness of the hole injection layers (HIL), or the number or thickness of the third emission layer (EML) 434, or the second emission layer Regardless of the number or thickness of (EML) 424, or regardless of the number or thickness of the first emission layer (EML) 414, or the second electrode 404 and the third emission layer (EML) 434 Regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 424 and the third emission layer (EML) 434, or the first Regardless of the number or thickness of all organic layers between the emission layer (EML) 414 and the second emission layer (EML) 424, the emission position (L3) of the first emission layer (EML) 414 is The electrode 404 is set to be located within a range of 2,050 Å to 2,600 Å. Alternatively, the light emission position L3 of the first emission layer EML 414 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.

Accordingly, the number of the at least one 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 third From the second electrode 404 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, the thickness of the first emission layer. The position L3 of the first emission layer EML 414 may be set to be located within a range of 2,050Å to 2,600Å. Alternatively, the number of the at least one 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 third Half of the second electrode 404 regardless of the number of emission layers, the thickness of the third emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the first emission layers, and the thickness of the first emission layer. The position L3 of the first emission layer EML 414 from the slope may be set to be located within a range of 2,050Å to 2,600Å.

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 emission layer (EML) 414 and the first electrode 402 may be referred to as an organic layer. Accordingly, all organic layers between the substrate 301 and the first emission 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, regardless of the number or thickness of the first electrodes 402, or regardless of the number or thickness of the electron blocking layer (EBL), or hole injection Regardless of the number or thickness of the layers (HIL), or the number or thickness of the third emission layers (EML) 434, or the number or thickness of the second emission layers (EML) 424, or 1 Regardless of the number or thickness of the emission layers (EML) 414, or regardless of the number or thickness of all organic layers between the second electrode 404 and the third emission layer (EML) 434, or the second Regardless of the number or thickness of all organic layers between the emission layer (EML) 424 and the third emission layer (EML) 434, or the first emission layer (EML) 414 and the second emission layer (EML) ( 424), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the substrate 401 and the first emission layer (EML) 414, the second electrode 404 From, the position L0 of the first electrode 402 may be set to be located 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 within a range of 3,500 Å to 4,500 Å.

Accordingly, the number of the at least one 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 emission layer, the thickness of the third emission layer, the number of the second emission layer, the thickness of the second emission layer, the number of the first emission layer, the first emission layer The position L0 of the first electrode 402 from the second electrode 404 may be set to be within a range of 3,500 Å to 4,500 Å regardless of the thickness of. Or, at least one number 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 second organic layers, 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 emission layer, the thickness of the third emission layer, the number of the second emission layer, the thickness of the second emission layer, the number of the first emission layer, the first emission 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 illustrates an example of the present invention, and may be selectively configured according to a structure or characteristic of a white organic light emitting device, but is not limited thereto.

36 is a view showing a light emission position of an organic light emitting diode according to a tenth exemplary embodiment of the present invention.

In FIG. 36, the horizontal axis represents the wavelength region of light, and the vertical axis represents the emission positions of the light emitting layers constituting the light emitting part from the second electrode 404, which may be referred to as a contour map. Here, except for the first electrode 402 and the second electrode 404, when the EPEL structure of the present invention is applied, the emission positions of the emission layers at the emission peak are shown. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown.

Since the third emission layer (EML) 434 constituting the third emission part 430 is a blue emission layer, the peak wavelength range of the emission region of the third emission layer (EML) 434 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the emission position of the third emission layer (EML) 434 in the range of 250 Å to 800 Å, the emission peak 434E of the third emission layer (EML) 434 is between 440 nm and 480 nm. To be located. Accordingly, the third emission layer (EML) 434 can emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 434 constituting the third emission unit 430. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 434 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 434 emits light from 440 nm to 650 nm, which is the emission region of the third emission layer (EML) 434.

In FIG. 36, the third emission layer (EML) 434 does not include an auxiliary emission layer, and the third emission layer (EML) 434 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 434 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the second emission layer (EML) 424 constituting the second emission part 420 is a blue emission layer, the peak wavelength range of the emission region of the second emission layer (EML) 424 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the emission position of the second emission layer (EML) 424 in the range of 1,450 Å to 1,950 Å, the emission peak 424E of the second emission layer EML 424 is 440 nm to 480 To be located in nm. Accordingly, the second emission layer (EML) 44 can emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the second emission layer (EML) 424 constituting the second emission unit 420. In this case, the peak wavelength range of the emission region of the second emission layer (EML) 424 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 424 emits light from 440 nm to 650 nm, which is an emission region.

In FIG. 36, the second emission layer (EML) 424 does not include an auxiliary emission layer, and the second emission layer (EML) 424 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 424 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the first emission layer (EML) 414 constituting the first emission part 410 is a yellow-green emission layer, the peak wavelength of the emission region of the first emission layer (EML) 414 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, the emission position of the first emission 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. Accordingly, maximum efficiency can be achieved by allowing light to emit light from 510 nm to 580 nm in the first emission layer (EML) 414.

In addition, the first emission layer (EML) 414 of the first emission unit 410 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light from 510 nm to 650 nm.

In addition, the first emission layer (EML) 414 of the first emission unit 410 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light from 510 nm to 650 nm.

In addition, the first emission layer (EML) 414 of the first emission unit 410 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light in the 540 nm to 650 nm emission region.

Accordingly, as the first emission layer (EML) 414, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the first emission layer (EML) 314 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the first emission layer (EML) 414 emits light in the 510 nm to 650 nm emission region.

In FIG. 36, the first emission layer (EML) 414 does not include an auxiliary emission layer, and the first emission layer (EML) 414 is a yellow-green emission layer as an example to indicate the emission position. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 414 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

That is, the maximum emission range of the blue emission layer, 440 nm to 470 nm, and the maximum emission range of the yellow-green emission layer, 530 nm to 570 nm, must be made to emit light. Maximum efficiency can be achieved in the white area. It can be seen that the emission layer can achieve maximum efficiency by setting the emission position of the emission layer of the present invention to correspond to the emission region. In addition, the EPEL structure of the present invention includes the number of at least one first organic layer, 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 third organic layers, and the third organic layer. Thickness, the number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers , Regardless of the thickness of the third emission layer, it can be seen that the emission layer can achieve maximum efficiency by configuring the first emission layer, the second emission layer, and the third emission layer to have a maximum emission 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 range of light, and the vertical axis represents the intensity of light emission. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 37, the example (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L1 of the third emission layer EML 434 is in the range of 250Å to 800Å from the second electrode 404, the minimum position is set to 250Å.

The embodiment (maximum position) is a portion set as the maximum position when the emission positions of the light emitting layers are set. For example, when the emission position L1 of the third emission layer EML 434 is in the range of 250Å to 800Å from the second electrode 404, the maximum position is set to 800Å.

The embodiment (optimum position) is a part set as the light emission position in the eighth embodiment of the present invention. For example, when the emission position L1 of the third emission layer (EML) 434 is in the range of 250Å to 800Å from the second electrode 404, the emission position in the embodiment is set in the range of 250Å to 800Å. .

As shown in FIG. 37, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, compared with the optimal position, it is as follows. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity decreases in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 19 below. When the efficiency of the comparative example is 100%, it shows the efficiency of the tenth example of the present invention.

Table 19 below compares the efficiencies of Comparative Examples and Examples of the present invention. 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 first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( The yellow-green) light emitting layer and the third light emitting part are composed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied.

As shown in Table 19, 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 and blue ( It can be seen that the blue) and white efficiency are almost similar to those of the comparative example.

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 20 below.

Table 20 below shows the efficiency of the example (minimum position) and the example (maximum position) when the efficiency of the example (optimum position) is 100%.

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 20, it can be seen that the efficiency of red, green, blue, and white decreases at the boundary between the example (minimum position) and the example (maximum position). . In addition, it can be seen that the efficiency of the embodiment (minimum position) in red, green, blue, and white decreases more than the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the optimum position of the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is deviated.

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 emission layer and the third emission layer may include an emission layer emitting the same color.

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

The emission position of the third emission layer may be set in a range of 250 Å to 800 Å from the second electrode.

The emission position of the second emission layer may be set in a range of 1,450 Å to 1,950 Å from the second electrode.

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

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

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

38 is a diagram illustrating a white organic light emitting diode according to an eleventh embodiment of the present invention.

The white organic light-emitting device 400 illustrated 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 part 430. In describing the present embodiment, descriptions of components that are the same as or corresponding to the previous embodiment will be omitted. In this embodiment, the emission positions of the emission layers are set from the first electrode, and the emission positions may be set from the first electrode according to the device design.

The position of the second electrode 404 is set to be 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, the emission peak of the emission layers constituting the first light-emitting part 410, the second light-emitting part 420, and the third light-emitting part 430 It is possible to improve the efficiency of the light emitting layers by placing is positioned at a specific wavelength and emitting light of that specific wavelength. In addition, the first emission part, the second emission part, and the third emission part have a maximum emission range in the emission regions of the first emission layer, the second emission layer, and the third emission layer (Emission Position of Emitting Layers). It has a structure. In addition, two of the first emission layer, the second emission layer, and the third emission layer include an emission layer emitting the same color, thereby providing a white organic light-emitting device capable of further improving luminous efficiency. The emission layer emitting the same color may be referred to as a light emitting layer including at least one emission 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 doing.

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 emission layer EML 414. In addition, 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 emission layer EML 414. In addition, the first hole transport layer (HTL) 412 and the electron blocking layer (EBL) may be configured as a single layer.

The first emission layer (EML) 414 is formed of a yellow-green emission layer. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm.

In addition, the first emission layer (EML) 414 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or It may be composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof. When a red emission layer is further formed on the yellow-green emission layer, the efficiency of the red emission layer may be further improved. The red emission layer may be formed above or below the yellow-green emission layer.

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 ( 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) 414 may be configured identically or differently above and below.

In addition, the peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, peak wavelengths of the emission regions of the yellow and red emission layers of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

In addition, the peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission 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 an emission region. When it is composed of two layers of the red emission layer and the green emission layer, color reproducibility may be improved.

In addition, the peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, peak wavelengths of the emission regions of the yellow and red emission layers of the first emission layer (EML) 414 may be in the range of 540 nm to 650 nm. Here, the peak wavelength may be an emission region. In the case of comprising two layers of the yellow light emitting layer and the red light emitting layer, the luminous efficiency of the red light emitting layer may be increased.

In addition, the first emission layer (EML) 414 may be formed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. When the red emission layer and the yellow-green emission layer are formed of two layers, the emission efficiency of the red emission layer may be increased. In this case, the peak wavelength of the emission region of the first emission layer (EML) 414 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The first emission layer (EML) 414 is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or yellow- When composed of one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength of the emission region of the second emission layer (EML) 124 is 510 nm to 650 It can be in the range of nm. Here, the peak wavelength may be an emission 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 emission layer (EML) 414 and the first electrode 402 may be referred to as an organic layer. Accordingly, all organic layers between the substrate 401 and the first emission 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, regardless of the number or thickness of the first electrodes 402, 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 substrate 401 and the first emission layer (EML) 414, the first emission layer (EML) 414 The light emission position L1 is set to be located within a range of 1,500 Å to 2,050 Å from the first electrode 402. Alternatively, the light emission position L1 of the first emission 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, the position (L1) of the first emission layer (EML) 414 from the first electrode 402 is 1,500 Å to 2,050 Å, regardless of the number of the at least one first organic layer and the thickness of the first organic layer. It can be set to be within the range of. Alternatively, regardless of the number of the at least one first organic layer and the thickness of the first organic layer, the emission position L1 of the first emission layer (EML) 414 is determined by the substrate 401 and the first electrode 402. ) Can be set to be located in the range of 1,500Å to 2,050Å 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 additionally formed under the second hole transport layer HTL 422. A hole blocking layer HBL may be additionally formed on the second emission layer EML 424. An electron blocking layer EBL may be additionally formed under the second emission layer EML 424.

The second emission layer (EML) 424 is formed of a blue emission layer including a blue emission layer or an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

The auxiliary emission layer may be composed of one of a yellow-green emission layer or a red emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved. When configuring the second emission layer (EML) 424 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is a second emission layer (EML) ( It is also possible to configure above or below 424). In addition, as the auxiliary emission layer, a yellow-green emission layer, a red emission layer, or a green emission layer may be configured identically or differently above and below the second emission layer (EML) 424. I can. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

When the auxiliary emission layer is formed on the second emission layer (EML) 424, the peak wavelength of the emission region of the first emission layer (EML) 424 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission region.

A first charge generation layer (CGL) 440 may be further formed between the first light-emitting part 410 and the second light-emitting part 420. The first charge generation layer 140 may include an N-type charge generation layer and a P-type charge generation layer.

The first emission layer (EML) 414, the first electron transport layer (ETL) 416, the first charge generation layer (CGL) 440, the second hole transport layer (HTL) 422, hole blocking All layers, such as the layer 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 emission layer (EML) 414 and the second emission layer (EML) 424 and the first emission layer (EML) 414 may be referred to as an organic layer. Accordingly, all organic layers between the first emission layer (EML) 414 and the second emission layer (EML) 424 may be referred to as a second organic layer.

Regardless of the number or thickness of the first electron transport layers (ETL) 416, regardless of the number or thickness of the second hole transport layers (HTL) 422, or of the first charge generation layer (CGL) 440 Regardless of the number or thickness of the hole blocking layers (HBL), regardless of the number or thickness of the electron blocking layers (EBL), or the number or thickness of the hole injection layers (HIL), or the above Regardless of the number or thickness of first emission layers (EML) 414, or regardless of the number or thickness of all organic layers between the substrate 401 and the first emission layer (EML) 414, or the first emission layer Regardless of the number or thickness of all organic layers between the (EML) 414 and the second emission layer (EML) 424, the emission position (L2) of the second emission layer (EML) 424 is the first electrode It can be set to be located in the range of 2,150 Å to 2,600 Å from (402). Alternatively, the emission position L2 of the second emission 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 the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, the The emission position L2 of the second emission 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 the number of the at least one first organic layer, 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 emission layers, the thickness of the first emission layer, The light emission position L2 of the second emission 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. It 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 436.

A hole injection layer HIL may be additionally formed under the third hole transport layer HTL 432.

A hole blocking layer HBL may be additionally formed on the third emission layer EML 434. The third electron transport layer (ETL) 436 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer EBL may be additionally formed under the third emission layer EML 434. The third hole transport layer (HTL) 432 and the electron blocking layer (EBL) may be configured as a single layer.

The third emission layer (EML) 434 is formed of one of a blue emission layer or a blue emission layer including an auxiliary emission layer capable of emitting a different color. The blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

The auxiliary emission layer may be composed of one of a yellow-green emission layer, a red emission layer, a green emission layer, or a combination thereof. When the auxiliary emission layer is further formed, the luminous efficiency of the green emission layer or the red emission layer may be further improved. When configuring the third emission layer (EML) 434 including the auxiliary emission layer, the yellow-green emission layer, the red emission layer, or the green emission layer is the third emission layer (EML) It is also possible to configure above or below 434. In addition, as the auxiliary emission layer, a yellow-green or red emission layer or a green emission layer may be configured identically or differently above and below the third emission layer (EML) 434. have. The position or number of light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not limited thereto.

When the auxiliary emission layer is formed on the third emission layer (EML) 434, the peak wavelength of the emission region of the third emission layer (EML) 434 may be in the range of 440 nm to 650 nm. have. Here, the peak wavelength may be an emission region.

A second charge generation 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 emission layer (EML) 424, the second electron transport layer (ETL) 426, a third hole transport layer (HTL) 432, the second charge generation layer (CGL) 450, a hole injection layer All layers such as (HIL), electron blocking layer (EBL), and hole blocking layer (HBL) may be referred to as organic layers. All organic layers between the second emission layer (EML) 424 and the third emission layer (EML) 434 and the second emission layer (EML) 424 may be referred to as an organic layer. Accordingly, all organic layers between the second emission layer (EML) 424 and the third emission layer (EML) 434 may be referred to as a third organic layer.

Regardless of the number or thickness of the second emission layers (EML) 424, regardless of the number or thickness of the second electron transport layers (ETL) 426, or the number or thickness of the third hole transport layers (HTL) 432 Regardless of, regardless of the number or thickness of the second charge generation layers (CGL) 450, regardless of the number or thickness of the hole injection layers (HIL), or regardless of the number or thickness of the electron blocking layers (EBL) Without, or regardless of the number or thickness of the hole blocking layers (HBL), or the number or thickness of the first emission layers (EML) 414, or the substrate 401 and the first emission layer (EML) 414 ), regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the first emission layer (EML) 414 and the second emission layer (EML) 424, or 2 Regardless of the number or thickness of all organic layers between the emission layer (EML) 424 and the third emission layer (EML) 434, the emission position (L3) of the third emission layer (EML) 434 is It can be set to be located within a range of 3,300 Å to 3,850 Å from the electrode 402. Alternatively, the light emission position L3 of the third emission layer EML 434 may be set to be located 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 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 emission layers, the thickness of the first emission layer, the third Regardless of the number of organic layers, the thickness of the third organic layer, the number of the second emission layers, and the thickness of the second emission layer, the emission position L3 of the third emission layer (EML) 434 is the first electrode 402 ) Can be set to be located in the range of 3,300Å to 3,850Å. Alternatively, at least one 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 third organic layers, the thickness of the third organic layer, the first Regardless of the number of emission layers, the thickness of the first emission layer, the number of the second emission layers, and the thickness of the second emission layer, the emission position L3 of the third emission layer (EML) 434 is between the substrate 401 and the substrate 401. It may be set to be located within a range of 3,300 Å to 3,850 Å from the interface of the first electrode 402.

Further, all layers such as the third emission 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 emission layer (EML) 434 and the second electrode 404 and the third emission layer (EML) 434 may be referred to as an organic layer. Accordingly, all organic layers between the third emission 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 layers (ETL) 436, regardless of the number or thickness of the electron injection layers (EIL), or the number or thickness of the hole blocking layers (HBL), or the third Regardless of the number or thickness of the emission layers (EML) 434, regardless of the number or thickness of the second emission layers (EML) 424, or regardless of the number or thickness of the first emission layers (EML) 414, Alternatively, regardless of the number or thickness of all organic layers between the substrate 401 and the first emission layer (EML) 414, or the first emission layer (EML) 414 and the second emission layer (EML) 424 ) Regardless of the number or thickness of all organic layers between, or regardless of the number or thickness of all organic layers between the second emission layer (EML) 424 and the third emission layer (EML) 434, or 3 Regardless of the thickness of all organic layers between the emission layer (EML) 434 and the second electrode 404, the position (L0) of the second electrode 404 is 3,500Å from the first electrode 402 It can be set to be located within the range of 4,500Å. Alternatively, the position L0 of the second electrode 404 may be set to be located within a range of 3,500 Å to 4,500 Å from the interface between the substrate 401 and the first electrode 402.

Accordingly, at least one 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 404, the position L0 of the second electrode 404 may be set to be located within a range of 3,500 Å to 4,500 Å from the first electrode 402. Or, the number of the at least one first organic layer, 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 third organic layers, the thickness of the third organic layer, the fourth The number of organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the third emission layer Regardless of the thickness of the second electrode 404, the position L0 of the second electrode 404 may be set to be located 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 emission position L3 of the third emission layer EML 434 may be set to be located within a range of 4,500 Å to 5,100 Å from the first electrode 402. In addition, 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 emission position L3 of the third emission 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) can be set to be located in the range of 4,550Å to 6,000Å. In addition, when the emission position L3 of the third emission layer EML 434 is set to 5,100Å from the first electrode 402, the position L0 of the second electrode 404 is the first It can be set to be located 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 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 third organic layers, the thickness of the third organic layer, The number of the fourth organic layers, the thickness of the fourth organic layer, the number of the first emission layers, the thickness of the first emission layer, the number of the second emission layers, the thickness of the second emission layer, the number of the third emission layers, the Regardless of the thickness of the third emission layer, the position of the second electrode 404 from the first electrode 402 and the positions of the emission layers may be set.

The structure shown in FIG. 38 illustrates an example of the present invention, and may be selectively configured according to the structure or characteristics of the organic light emitting device, but is not limited thereto.

39 is a diagram illustrating a light emission position of an organic light emitting diode 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 emission positions of the light emitting layers constituting the light emitting part from the first electrode 402, which may be referred to as a contour map. Here, except for the second electrode 404, when the EPEL structure of the present invention is applied, the emission positions of the emission layers are shown at the emission peak. In addition, the emission positions of the emission layers having the maximum emission range in the emission regions of the emission layers are shown.

Since the first emission layer (EML) 414 constituting the first emission part 410 is a yellow-green emission layer, the peak wavelength of the emission region of the first emission layer (EML) 414 ( peak wavelength) 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 yellow-green emission layer emits light from 510 nm to 580 nm, which is the emission region of the yellow-green emission layer.

Accordingly, the emission position of the first emission layer (EML) 414 is set in the range of 1,500 Å to 2,050 Å, so that the emission peak 414E is located in the range of 510 nm to 580 nm. Accordingly, maximum efficiency can be achieved by allowing light to emit light from 510 nm to 580 nm in the first emission layer (EML) 414.

In addition, the first emission layer (EML) 414 of the first emission unit 410 may be formed of two layers of a red emission layer and a green emission layer according to a characteristic or structure of a device. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the green emission layer may be in the range of 510 nm to 560 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light from 510 nm to 650 nm.

In addition, the first emission layer (EML) 414 of the first emission unit 410 is composed of two layers of a red emission layer and a yellow-green emission layer according to the characteristics or structure of the device. can do. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. The peak wavelength of the emission region of the yellow-green emission layer may be in the range of 510 nm to 580 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light from 510 nm to 650 nm.

In addition, the first emission layer (EML) 414 of the first emission unit 310 may be formed of two layers, a yellow emission layer and a red emission layer, according to a characteristic or structure of a device. The peak wavelength of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. The peak wavelength of the emission region of the red emission layer may be in the range of 600 nm to 650 nm. Accordingly, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the first emission layer (EML) 414 emits light in the 540 nm to 650 nm emission region.

Accordingly, as the first emission layer (EML) 414, a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or When one of a yellow-green emission layer and a red emission layer, or a combination thereof, the peak wavelength range of the emission region of the first emission layer (EML) 314 is 510 It can range from nm to 650 nm. In this case, the maximum efficiency can be achieved in the white region of the contour map when the first emission layer (EML) 414 emits light in the 510 nm to 650 nm emission region.

In FIG. 39, the first emission layer (EML) 414 does not include an auxiliary emission layer, and the first emission layer (EML) 414 is a yellow-green emission layer as an example to indicate the emission position. Accordingly, the peak wavelength range of the emission region of the first emission layer (EML) 414 may exhibit maximum efficiency in the range of 510 nm to 580 nm.

Since the second emission layer (EML) 424 constituting the second emission part 420 is a blue emission layer, the peak wavelength range of the emission region of the second emission layer (EML) 424 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the emission position of the second emission layer (EML) 424 in the range of 2,150 Å to 2,600 Å, the emission peak 424E of the second emission layer (EML) 424 is 440 nm to 480 To be located in nm. Accordingly, the second emission layer (EML) 44 can emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the second emission layer (EML) 424 constituting the second emission unit 420. In this case, the peak wavelength range of the emission region of the second emission layer (EML) 424 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the second emission layer (EML) 424 emits light from 440 nm to 650 nm, which is an emission region.

In FIG. 39, the second emission layer (EML) 424 does not include an auxiliary emission layer, and the second emission layer (EML) 424 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the second emission layer (EML) 424 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

Since the third emission layer (EML) 434 constituting the third emission part 430 is a blue emission layer, the peak wavelength range of the emission region of the third emission layer (EML) 434 May range from 440 nm to 480 nm. The maximum efficiency can be achieved in the white region of the contour map only when the blue emission layer emits light from 440 nm to 480 nm, which is the emission region of the blue emission layer.

Therefore, by setting the emission position of the third emission layer (EML) 434 in the range of 3,300 Å to 3,850 Å, the emission peak 434E of the third emission layer (EML) 434 is 440 nm to 480 To be located in nm. Accordingly, the third emission layer (EML) 434 can emit light at 440 nm to 480 nm, thereby achieving maximum efficiency.

In addition, the blue emission layer may include one of a blue emission layer, a deep blue emission layer, or a sky blue emission layer.

In addition, a yellow-green or red emission layer or a green emission layer may be formed as an auxiliary emission layer on the third emission layer (EML) 434 constituting the third emission unit 430. In this case, the peak wavelength range of the emission region of the third emission layer (EML) 434 may be in the range of 440 nm to 650 nm. Therefore, in this case, the maximum efficiency can be achieved in the white region of the contour map only when the third emission layer (EML) 434 emits light from 440 nm to 650 nm, which is the emission region of the third emission layer (EML) 434.

In FIG. 39, the third emission layer (EML) 434 does not include an auxiliary emission layer, and the third emission layer (EML) 434 shows a light emission position using a blue emission layer as an example. Accordingly, the peak wavelength range of the emission region of the third emission layer (EML) 434 may exhibit maximum efficiency in the range of 440 nm to 480 nm.

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

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

In addition, in the light emitting region having the specific wavelength, the light emitting range capable of achieving the maximum efficiency of the light emitting layers may be referred to as the maximum light emitting range. That is, the peak wavelength may be the 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 440nm to 470nm.

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

40 is a diagram showing an EL spectrum according to the eleventh embodiment of the present invention.

In FIG. 40, the horizontal axis represents the wavelength range of light, and the vertical axis represents the intensity of light emission. The emission intensity is a value expressed as a relative value based on the maximum value of the EL spectrum.

In FIG. 40, the example (minimum position) is a portion set to the minimum position when the emission positions of the emission layers are set. For example, when the light emission position L1 of the first emission 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 portion set as the maximum position when the emission positions of the light emitting layers are set. When the emission position L1 of the first emission 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.

The embodiment (optimum position) is a part set as the light emission position in the eighth embodiment of the present invention. For example, when the light emission position L1 of the first emission layer (EML) 414 is in the range of 1,500 Å to 2,050 Å from the first electrode 402, the emission position in the embodiment is in the range of 1,500 Å to 2,050 Å. Is set to.

As shown in FIG. 40, in the case of deviating from the minimum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, the light emission intensity decreases in the peak wavelength range of 510 nm to 580 nm of yellow-green light, and out of the peak wavelength range of yellow-green light. Able to know. In addition, it can be seen that the light emission intensity significantly decreases in the range of 600 nm to 650 nm, which is the peak wavelength range of red light.

In addition, in the case of deviating from the maximum position of the emission position in the EPEL (Emission Position of Emitting Layers) structure of the present invention, when compared with the optimum position, the following is shown. It can be seen that the light emission intensity decreases in the range of the peak wavelength of blue light from 440 nm to 480 nm. In addition, it can be seen that the light emission intensity is significantly reduced in the range of 510 nm to 580 nm, which is a peak wavelength range of yellow-green light.

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

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied and the comparative example are as shown in Table 21 below. Assuming that the efficiency of the comparative example is 100%, it shows the efficiency of the eleventh embodiment of the present invention.

Table 21 below compares the efficiencies of Comparative Examples and Examples of the present invention. 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 first light emitting part is a blue light emitting layer, and the second light emitting part is yellow-green ( The yellow-green) light emitting layer and the third light emitting part are composed of a blue light emitting layer. The embodiment is a top emission type white organic light-emitting device when the optimum position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied.

As shown in Table 21, 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 green and blue ( It can be seen that the blue) and white efficiency are almost similar to those of the comparative example.

The panel efficiency of the white organic light-emitting device to which the EPEL (Emission Position of Emitting Layers) 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 example (minimum position) and the example (maximum position) when the efficiency of the example (optimum position) is 100%.

Panel efficiency is measured when the driving current density is 10mA/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) is measured.

As shown in Table 22, it can be seen that the efficiency of red, green, blue, and white decreases at the boundary between the example (minimum position) and the example (maximum position). . In addition, it can be seen that the efficiency of the embodiment (minimum position) in red, green, blue, and white decreases more than the embodiment (maximum position).

Accordingly, it can be seen that the panel efficiency decreases when the optimum position of the emission position of the EPEL (Emission Position of Emitting Layers) structure of the present invention is deviated.

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

The emission position of the first emission layer may be set in the range of 1,500 Å to 2,050 Å from the first electrode.

The emission position of the second emission layer may be set in a range of 2,150 Å to 2,600 Å from the first electrode.

The emission position of the third emission layer may be set in a range of 3,300 Å to 3,850 Å from the first electrode.

The first emission layer may be one of a yellow-green emission layer, a yellow emission layer and a red emission layer, a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof.

The second emission layer and the third emission layer may be formed of a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof.

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

As described above, it can be seen that when the EPEL (Emission Position of Emitting Layers) structure of the present invention is applied, the light emission intensity of the emission layer can be increased. 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 device according to the tenth and eleventh embodiments of the present invention. In describing the present embodiment, descriptions of components that are the same as or corresponding to the previous embodiment will be omitted.

41, the 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 part 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 illustrated in an inverted staggered structure, but may be formed in a coplanar structure.

The substrate 40 may be made of glass, metal, or plastic.

The gate electrode 4115 is formed on the substrate 40. The gate insulating layer 4120 is formed on the gate electrode 4115.

The semiconductor layer 4131 is formed on the gate insulating layer 4120.

The source electrode 4133 and the drain electrode 4135 may be formed on the semiconductor layer 4131.

The protective layer 4140 is formed on the source electrode 4133 and the drain electrode 4135.

The color filter 4145 is formed on the first protective layer 4140.

The overcoat layer 4150 is formed on the color filter 4145.

The first electrode 402 is formed on the overcoat layer 4150. The first electrode 402 is electrically connected to the drain electrode 4135 through a contact hole CH in a predetermined region of the protective layer 4140 and the overcoat layer 4150. In FIG. 41, the drain electrode 4135 and the first electrode 4102 are shown to be electrically connected. However, the source electrode (CH) in a predetermined region of the protective layer 4140 and the overcoat layer 4150 is It is also possible for the 4133 and the first electrode 402 to be electrically connected.

The 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 unit 4180 includes a first light-emitting part 410, a second light-emitting part 420 and a first light-emitting part 410 formed on the first electrode 402 and It consists of a third light emitting unit 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 encapsulation part serves to prevent moisture from penetrating into the light emitting part 4180. The encapsulation substrate may be made of glass or plastic, or may be made of 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 various modifications can be made without departing from the spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but to explain the technical idea, 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 limiting. The scope of protection of the present invention should be interpreted by 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 emission layer
124, 224,324, 424: second emission layer
134, 234,334, 434: third emission layer

Claims (38)

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 on the first light-emitting unit; And
It includes a third light emitting layer, consisting of a third light emitting portion on the second light emitting portion,
The first light-emitting unit, the second light-emitting unit, and the third light-emitting unit are an Emission Position of Emitting Layers (EPEL) structure having a maximum light emission range in light-emitting regions of the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer. ,
The first light-emitting layer is 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 one of a blue light-emitting layer and a green light-emitting layer, or a combination thereof,
The second light-emitting layer 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 and a red light-emitting layer, or a combination thereof,
The third emission layer is a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof. The method of claim 1,
The organic light-emitting device is a white organic light-emitting device, characterized in that the bottom emission type. The method of claim 2,
The white organic light-emitting device, characterized in that the position of the first electrode is set in the range of 4,500 Å to 6,000 Å from the second electrode. The method of claim 2,
A white organic light-emitting device, characterized in that the emission position of the third emission layer is set in the range of 200 Å to 800 Å from the second electrode. The method of claim 2,
A white organic light-emitting device, characterized in that the emission position of the second emission layer is set in the range of 1,800 Å to 2,550 Å from the second electrode. The method of claim 2,
A white organic light-emitting device, characterized in that the emission position of the first emission layer is set in a range of 2,650 Å to 3,300 Å from the second electrode. delete delete delete The method of claim 1,
The emission region of the first emission layer is in the range of 440 nm to 650 nm,
The emission region of the second emission layer is in the range of 510 nm to 650 nm,
A white organic light-emitting device, characterized in that the emission area of the third emission layer is in the range of 440 nm to 650 nm. The method of claim 1,
The maximum emission range of the first emission layer is in the range of 440 nm to 470 nm,
The maximum emission range of the second emission layer is in the range of 530 nm to 570 nm,
The white organic light-emitting device, characterized in that the maximum emission range of the third emission layer is in the range of 440nm to 470nm. 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 on the first light-emitting unit; And
It includes a third light emitting layer, consisting of a third light emitting portion on the second light emitting portion,
The organic light emitting device is a bottom emission type,
The second emission layer and the third emission layer include an emission layer emitting the same color,
The emission region of the first emission layer is in the range of 510 nm to 650 nm,
The emission region of the second emission layer is in the range of 440 nm to 650 nm,
The emission region of the third emission layer is 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,
The white organic light-emitting device, characterized in that the maximum emission range of the third emission layer is in the range of 440nm to 470nm. The method of claim 12,
The white organic light-emitting device, characterized in that the position of the first electrode is set in a range of 3,500 Å to 4,500 Å from the second electrode. The method of claim 12,
A white organic light-emitting device, characterized in that the emission position of the third emission layer is set in the range of 250 Å to 800 Å from the second electrode. The method of claim 12,
A white organic light-emitting device, characterized in that the emission position of the second emission layer is set in the range of 1,450 Å to 1,950 Å from the second electrode. The method of claim 12,
A white organic light-emitting device, characterized in that the emission position of the third emission layer is set in the range of 2,050Å to 2,600Å from the second electrode. The method of claim 12,
The first emission layer is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof. The method of claim 12,
The second emission layer and the third emission layer are a blue emission layer, a blue emission layer and a yellow-green emission layer, or a blue emission layer and a red emission layer, or one of a blue emission layer and a green emission layer, or a combination thereof. device. delete delete 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 on the first light-emitting unit; And
It includes a third light emitting layer, consisting of a third light emitting portion on the second light emitting portion,
The organic light emitting device is a top emission type,
The first light-emitting layer is 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 one of a blue light-emitting layer and a green light-emitting layer, or a combination thereof,
The second light-emitting layer 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 and a red light-emitting layer, or a combination thereof,
The third emission layer is a blue emission layer, a blue emission layer and a yellow-green emission layer, a blue emission layer and a red emission layer, or a blue emission layer and a green emission layer, or a combination thereof. The method of claim 21,
The white organic light-emitting device, characterized in that the position of the second electrode is set in the range of 4,700 Å to 5,400 Å from the first electrode. The method of claim 21,
A white organic light-emitting device, characterized in that the emission position of the first emission layer is set in the range of 150 Å to 700 Å from the first electrode. The method of claim 21,
A white organic light-emitting device, characterized in that the emission position of the second emission layer is set in a range of 1,600 Å to 2,300 Å from the first electrode. The method of claim 21,
A white organic light-emitting device, characterized in that the emission position of the third emission layer is set in the range of 2,400 Å to 3,100 Å from the first electrode. 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 on the first light-emitting unit; And
It includes a third light emitting layer, consisting of a third light emitting portion on the second light emitting portion,
The organic light emitting device is a top emission type,
The second emission layer and the third emission layer include an emission layer emitting the same color,
The emission region of the first emission layer is in the range of 510 nm to 650 nm,
The emission region of the second emission layer is in the range of 440 nm to 650 nm,
The emission region of the third emission layer is 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,
The white organic light-emitting device, characterized in that the maximum emission range of the third emission layer is in the range of 440nm to 470nm. The method of claim 26,
The white organic light-emitting device, characterized in that the position of the second electrode is set in the range of 4,700 Å to 5,400 Å from the first electrode. The method of claim 26,
A white organic light-emitting device, characterized in that the emission position of the first emission layer is set in the range of 200 Å to 700 Å from the first electrode. The method of claim 26,
A white organic light-emitting device, characterized in that the emission position of the second emission layer is set in a range of 1,200 Å to 1,800 Å from the first electrode. The method of claim 26,
A white organic light-emitting device, characterized in that the emission position of the third emission layer is set in the range of 2,400 Å to 3,100 Å from the first electrode. The method of claim 26,
The first emission layer is a yellow-green emission layer, a yellow emission layer and a red emission layer, or a red emission layer and a green emission layer, or a yellow-green emission layer and a red emission layer, or a combination thereof. The method of claim 26,
The second emission layer and the third emission layer are a blue emission layer, a blue emission layer and a yellow-green emission layer, or a blue emission layer and a red emission layer, or one of a blue emission layer and a green emission layer, or a combination thereof. device. delete delete delete delete delete delete

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