KR102387097B1 - White organic light emitting device - Google Patents

Abstract

An object of the present invention is to provide a white organic light-emitting device capable of improving luminous efficiency and panel efficiency of a light emitting layer and improving a color viewing angle or color gamut according to a viewing angle.
A white organic light emitting diode according to the present invention includes a first light emitting layer, a first light emitting part positioned between the first electrode and the second electrode, and a second light emitting layer, and a second light emitting part positioned on the first light emitting part and a third light emitting layer, comprising a third light emitting unit positioned on the second light emitting unit, wherein at least two light emitting layers of the first light emitting layer, the second light emitting layer, and the third light emitting layer emit the same color; It is characterized in that the light emitting layers emitting the same color are disposed adjacent to each other.

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 and improving color viewing angle and color gamut.

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

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

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

The organic light emitting device is composed of an organic light emitting layer between two electrodes. Electrons and holes are respectively injected from the two electrodes into the organic light emitting layer to generate excitons according to the combination of electrons and holes. And, it is a device using the principle that light is generated when the generated exciton falls from an excited state to a ground state.

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

The organic light emitting diode implements a full color in sub-pixels emitting red (R), green (G), and blue (B) respectively. The sub-pixels emitting red (R), green (G), and blue (B) may represent color gamut with respective color coordinates of red (R), green (G), and blue (B). The color coordinates are highly dependent on the material of the light emitting layer. In particular, in the case of phosphorescent materials, triplet excitons contribute to light emission, so that a device with high efficiency can be realized compared to fluorescent materials.

However, efforts to improve color coordinates and color reproducibility of organic light emitting diodes are continuing in response to consumer demand for superior image quality.

As one method, there is a method of using the 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 in a blue host, or red, green, and blue dopants are added and used in a host material having a large band gap energy. However, this method has problems in that energy transfer to the dopant is incomplete and it is difficult to control the white balance.

In addition, there is a limit to the components of the dopant included in the light emitting layer due to the characteristics of the dopant itself. In addition, since the focus is focused on realizing white light when each light emitting layer is mixed, a wavelength characteristic having a peak wavelength value at a wavelength other than red, green, and blue is exhibited. Accordingly, there is a problem in that the luminous efficiency of red, green, and blue is deteriorated due to an undesired peak wavelength value.

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 wavelength region corresponding to the peak wavelength of each light emitting layer and the transmission region of the color filter. Therefore, the color range that can be expressed is narrowed, and there is a problem in realizing a desired color gamut.

And, when the blue light emitting layer and the yellow-green light emitting layer are composed of the two light emitting layers, the blue light emitting layer and the yellow-green light emitting layer are formed according to the difference in the cavity peaks. The light emitting layer has a different rate of spectral change according to the viewing angle. Accordingly, in order to control the spectral change rate according to the viewing angle of the blue light emitting layer and the yellow-green light emitting layer, the cavity peak of the yellow-green light emitting layer is adjusted to a position that is shifted from the desired position. Therefore, there is a problem that the efficiency of red, green, and blue is reduced.

Accordingly, the inventors of the present invention recognize the above-mentioned problems, and improve the efficiency of red, green, and blue in consideration of the spectral change rate and the cavity peak of the light emitting layers, and the color viewing angle according to the viewing angle. Several experiments were conducted to improve the color gamut.

Therefore, through various experiments, it is possible to improve the efficiency of red, green, and blue, and to improve the luminous efficiency of the light emitting layer and the color viewing angle or color gamut according to the viewing angle. invented the device.

A problem to be solved according to an embodiment of the present invention is to optimize the light emitting position of the light emitting layer, thereby improving the efficiency of red, green, and blue light and the light emission efficiency of the light emitting layer and the panel efficiency of white organic light emitting diodes. It is to provide an element.

An object to be solved according to an embodiment of the present invention is to provide a white organic light emitting device capable of improving device efficiency and color viewing angle or color gamut according to viewing angle by configuring at least two light emitting layers emitting the same color .

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

A white organic light emitting diode according to an embodiment of the present invention includes a first light emitting layer, a first light emitting part disposed between the first electrode and the second electrode, and a second light emitting layer, and is disposed on the first light emitting part a second light emitting part and a third light emitting layer, and including a third light emitting layer on the second light emitting part, and among the first light emitting layer, the second light emitting layer, and the third light emitting layer to improve luminous efficiency and color viewing angle. At least two light emitting layers emit the same color, and by disposing the light emitting layers emitting the same color adjacent to each other, the efficiency of red, green and blue is improved, and the luminous efficiency of the light emitting layer and Provided is a white organic light-emitting device capable of improving panel efficiency and improving a color viewing angle or color gamut according to a viewing angle.

The at least two light emitting layers may be the first light emitting layer and the second light emitting layer.

The first light emitting layer and the second light emitting layer may be one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

A peak wavelength (λmax) of the first emission layer and the second emission layer may be in a range of 440 nm to 480 nm.

The light emitting layer emitting a color different from the same color may be one of a yellow-green light emitting layer, or a green light emitting layer, or a red light emitting layer and a green light emitting layer, or a yellow light emitting layer and a red light emitting layer, or a yellow-green light emitting layer and a red light emitting layer, or a combination thereof. can

A peak wavelength (λmax) of the third emission layer may be in a range of 540 nm to 575 nm.

The at least two light emitting layers may be configured to be closer to the first electrode than to the second electrode.

The color viewing angle (Δu'v') at a 60° viewing angle of light emitted from the organic light emitting diode may be 0.016 or less.

The position of the first electrode may be in a range of 500 nm to 600 nm from the second electrode.

A light emission position of the third light emitting layer may be in a range of 20 nm to 80 nm from the second electrode.

An emission position of the second emission layer may be in a range of 150 nm to 200 nm from the second electrode.

An emission position of the first emission layer may be in a range of 270 nm to 330 nm from the second electrode.

The position of the second electrode may be in a range of 500 nm to 600 nm from the first electrode.

An emission position of the first emission layer may be in a range of 100 nm to 150 nm from the first electrode.

An emission position of the second emission layer may be in a range of 240 nm to 280 nm from the first electrode.

An emission position of the third emission layer may be in a range of 370 nm to 410 nm from the first electrode.

A white organic light emitting diode according to an embodiment of the present invention includes a first electrode and a second electrode facing each other on a substrate, and at least three light emitting units between the first electrode and the second electrode, At least two light emitting units among the at least three light emitting units are composed of light emitting layers emitting the same color, thereby improving the efficiency of red, green, and blue colors, and improving the light emitting efficiency and panel efficiency of the light emitting layer To provide a white organic light emitting device capable of improving the color viewing angle or color gamut according to the viewing angle.

The light emitting layers emitting the same color may be one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

A peak wavelength (λmax) of the emission layer may be in a range of 440 nm to 480 nm.

The light emitting layer emitting a color different from the same color among the at least three or more light emitting units may be one of a yellow-green light emitting layer or a green light emitting layer, a yellow-green light emitting layer and a red light emitting layer, or a combination thereof.

A peak wavelength (λmax) of the emission layer may be in the range of 540 nm to 575 nm.

A color viewing angle (Δu'v') at a viewing angle of 60° of light emitted from the organic light emitting diode may be 0.016 or less.

A white organic light emitting diode according to an embodiment of the present invention includes a first light emitting layer, a first light emitting part disposed between the first electrode and the second electrode, and a second light emitting layer, and is disposed on the first light emitting part A second light emitting unit and a third light emitting layer, and a third light emitting layer on the second light emitting unit, wherein the first light emitting layer, the second light emitting layer, and the third light emitting layer consider a spectrum change rate and a cavity peak. At least two of the light emitting layers of the first light emitting layer, the second light emitting layer and the third light emitting layer are composed of light emitting layers emitting light of the same color, thereby improving the efficiency of Red, Green and Blue. To provide a white organic light-emitting device capable of improving luminous efficiency and panel efficiency of a light emitting layer and improving a color viewing angle or color gamut according to a viewing angle.

The light emitting layers emitting the same color may be the first light emitting layer and the second light emitting layer, and the first light emitting layer and the second light emitting layer may be disposed adjacent to each other.

With the light emitting layers emitting the same color disposed adjacent to each other, the difference between the spectral change rate of the light emitting layer emitting a color different from the same color and the spectral change rate of the light emitting layers emitting the same color can be configured to be almost identical. there is.

With the light emitting layers emitting the same color, the difference between the spectral change rate of the light emitting layer emitting light of a color different from the same color and the spectral change rate of the light emitting layers emitting the same color may be configured to be substantially similar.

With a configuration in which the difference between the spectral change rate of the light emitting layer emitting a color different from the same color and the spectral change rate of the light emitting layers emitting the same color is substantially similar, the cavity peak of the light emitting layer emitting a color different from the same color emits light may be located in the area.

Due to the emission layers emitting the same color, a cavity peak of the emission layer emitting a color different from the same color and a cavity peak of the emission layers emitting the same color may be located in the emission region.

The peak wavelength (λmax) corresponding to the emission region of the emission layers emitting the same color is in the range of 440 nm to 480 nm, and the peak wavelength (λmax) corresponding to the emission region of the emission layer emitting a color different from the same color is It may range from 540 nm to 575 nm.

The light emitting layers emitting the same color may be configured to be closer to the first electrode than to the second electrode.

Light emission positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer may be set in consideration of the spectral change rate and the cavity peak of the light emitting layers to improve luminous efficiency and color viewing angle.

The position of the first electrode may be in a range of 500 nm to 600 nm from the second electrode.

A light emission position of the third light emitting layer may be in a range of 20 nm to 80 nm from the second electrode.

An emission position of the second emission layer may be in a range of 150 nm to 200 nm from the second electrode.

An emission position of the first emission layer may be in a range of 270 nm to 330 nm from the second electrode.

A color viewing angle (Δu'v') at a viewing angle of 60° of light emitted from the organic light emitting diode may be 0.016 or less.

The position of the second electrode may be in a range of 500 nm to 600 nm from the first electrode.

An emission position of the first emission layer may be in a range of 100 nm to 150 nm from the first electrode.

An emission position of the second emission layer may be in a range of 240 nm to 280 nm from the first electrode.

An emission position of the third emission layer may be in a range of 370 nm to 410 nm from the first electrode.

A white organic light emitting diode according to an embodiment of the present invention includes a first light emitting layer, a first light emitting part disposed between the first electrode and the second electrode, and a second light emitting layer, and is disposed on the first light emitting part A second light emitting unit and a third light emitting layer, and a third light emitting layer on the second light emitting unit, wherein the first light emitting layer, the second light emitting layer, and the third light emitting layer consider a spectrum change rate and a cavity peak. By setting the order of the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer, the efficiency of red, green, and blue is improved, and the light-emitting efficiency and panel efficiency of the light-emitting layer are improved, , to provide a white organic light-emitting device capable of improving a color viewing angle or color gamut according to a viewing angle.

At least two light emitting layers among the first light emitting layer, the second light emitting layer, and the third light emitting layer may be composed of light emitting layers emitting light of the same color.

The light emitting layers emitting the same color may be configured to be closer to the first electrode than to the second electrode.

The light emitting layers emitting the same color may be the first light emitting layer and the second light emitting layer, and the first light emitting layer and the second light emitting layer may be disposed adjacent to each other.

With the light emitting layers emitting the same color disposed adjacent to each other, the difference between the spectral change rate of the light emitting layer emitting a color different from the same color and the spectral change rate of the light emitting layers emitting the same color can be configured to be almost identical. there is.

With the light emitting layers emitting the same color, the difference between the spectral change rate of the light emitting layer emitting light of a color different from the same color and the spectral change rate of the light emitting layers emitting the same color may be configured to be substantially similar.

With a configuration in which the difference between the spectral change rate of the light emitting layer emitting a color different from the same color and the spectral change rate of the light emitting layers emitting the same color is substantially similar, the cavity peak of the light emitting layer emitting a color different from the same color emits light may be located in the area.

Due to the emission layers emitting the same color, a cavity peak of the emission layer emitting a color different from the same color and a cavity peak of the emission layers emitting the same color may be located in the emission region.

The peak wavelength (λmax) corresponding to the emission region of the emission layers emitting the same color is in the range of 440 nm to 480 nm, and the peak wavelength (λmax) corresponding to the emission region of the emission layer emitting a color different from the same color is It may range from 540 nm to 575 nm.

Light emission positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer may be set in consideration of the spectral change rate and the cavity peak of the light emitting layers to improve luminous efficiency and color viewing angle.

The position of the first electrode may be in a range of 500 nm to 600 nm from the second electrode.

A light emission position of the third light emitting layer may be in a range of 20 nm to 80 nm from the second electrode.

An emission position of the second emission layer may be in a range of 150 nm to 200 nm from the second electrode.

An emission position of the first emission layer may be in a range of 270 nm to 330 nm from the second electrode.

A color viewing angle (Δu'v') at a viewing angle of 60° of light emitted from the organic light emitting diode may be 0.016 or less.

The position of the second electrode may be in a range of 500 nm to 600 nm from the first electrode.

An emission position of the first emission layer may be in a range of 100 nm to 150 nm from the first electrode.

An emission position of the second emission layer may be in a range of 240 nm to 280 nm from the first electrode.

An emission position of the third emission layer may be in a range of 370 nm to 410 nm from the first electrode.

Details of other embodiments are included in the detailed description and drawings.

By optimizing the emission position of the emission layer according to an embodiment of the present invention, there is an effect of improving the efficiency of red, green, and blue.

In addition, by optimizing the light emitting position of the light emitting layer, there is an effect of improving the light emitting efficiency and panel efficiency of the light emitting layer, and the color viewing angle and color gamut.

By configuring the two light emitting layers emitting the same color to be adjacent to each other according to an embodiment of the present invention, there is an effect that the light emitting intensity of the light emitting layer can be improved.

In addition, since the luminous intensity of the light emitting layer is increased, luminous efficiency and color gamut are improved, and power consumption is lowered due to the improved efficiency, so that it can be applied to a large-area TV.

In addition, by configuring two light emitting layers emitting the same color, device efficiency is improved, and a color viewing angle or color gamut according to a viewing angle can be improved.

In addition, by configuring two light emitting layers emitting the same color in consideration of the spectral change rate and cavity peak of the light emitting layers, the difference in the spectral change rate of the light emitting layers can be made almost similar, so that the color viewing angle or color gamut according to the viewing angle can be improved there is.

In addition, since the difference in spectral change rates of the light emitting layers can be almost similar, the cavity peaks of the light emitting layers can be located in the light emitting region. Therefore, by locating the cavity peak of the light emitting layers in the light emitting region, the peak wavelength of the light emitting layers is positioned at a desired position, so that the luminous efficiency and device efficiency are improved, and the color viewing angle or color gamut according to the viewing angle can be improved.

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

1 is a schematic cross-sectional view showing a white organic light emitting diode according to a first embodiment of the present invention.
2 is a view showing a spectrum of a light emitting layer according to a first embodiment of the present invention.
3 is a diagram showing EL spectra according to a comparative example and a first embodiment of the present invention.
4 is a graph illustrating a spectrum change rate according to a viewing angle according to the first embodiment of the present invention.
5 is a view showing color coordinates according to a comparative example and a first embodiment of the present invention.
6 is a diagram illustrating a color viewing angle according to a comparative example and a first embodiment of the present invention.
7 is a view showing EL spectra according to Comparative Example 1 and Example 1 of the present invention.
8 is a view showing color viewing angles according to Comparative Example 1 and the first embodiment of the present invention.
9 is a schematic cross-sectional view illustrating a white organic light emitting diode according to a second exemplary embodiment of the present invention.
10 is a diagram illustrating a light emitting position of an organic light emitting diode according to a second exemplary embodiment of the present invention.
11 is a diagram showing an EL spectrum according to a second embodiment of the present invention.
12 is a diagram illustrating a color viewing angle according to a second exemplary embodiment of the present invention.
13 is a schematic cross-sectional view illustrating a white organic light emitting diode according to a third exemplary embodiment of the present invention.
14 is a diagram illustrating a light emitting position of an organic light emitting diode according to a third exemplary embodiment of the present invention.
15 is a diagram showing an EL spectrum according to a third embodiment of the present invention.
16 is a diagram illustrating a color viewing angle according to a third embodiment of the present invention.
17 is a diagram illustrating an organic light emitting display device according to an embodiment of the present invention.

Advantages and features of the present invention and methods of achieving them will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the technical field to which the present invention belongs It is provided to fully inform the possessor of the scope of the invention, and the present invention is only defined by the scope of the claims.

The shapes, sizes, proportions, angles, numbers, etc. disclosed in the drawings for explaining the embodiments of the present invention are illustrative and the present invention is not limited to the illustrated matters. Like reference numerals refer to like elements throughout. In addition, in describing the present invention, if it is determined that a detailed description of a related known technology may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. When 'including', 'having', 'consisting', etc. mentioned in this specification are used, other parts may be added unless 'only' is used. When a component is expressed in the singular, the case in which the plural is included is included unless otherwise explicitly stated.

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

In the case of a description of the positional relationship, for example, when the positional relationship of two parts is described as 'on', 'on', 'on', 'beside', etc., 'right' Alternatively, one or more other parts may be positioned between two parts unless 'directly' is used.

In the case of a description of a temporal relationship, for example, 'immediately' or 'directly' when a temporal relationship is described with 'after', 'following', 'after', 'before', etc. It may include cases that are not continuous unless this is used.

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

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

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

1 is a schematic cross-sectional view showing a white organic light emitting diode according to a first embodiment of the present invention.

The white organic light emitting diode 100 illustrated in FIG. 1 includes first and second electrodes 102 and 104 on a substrate 101 , a first light emitting unit 110 between the first and second electrodes 102 and 104 , and a second A light emitting unit 120 and a third light emitting unit 130 are provided.

The first electrode 102 is an anode for supplying holes, and may be formed of gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), etc., or an alloy thereof. , but is not necessarily limited thereto.

The second electrode 104 is a cathode for supplying electrons, and may be formed of a transparent conductive material such as TCO (Transparent Conductive Oxide), ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), IGZO (Indium Gallium Zinc Oxide), etc. may, but is not necessarily limited thereto. Alternatively, the second electrode 104 may be formed of a metallic material such as gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), or the like, or an alloy thereof, It is not necessarily limited to this. Alternatively, the second electrode 104 may include Transparent Conductive Oxide (TCO), Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), Indium Gallium Zinc Oxide (IGZO), and metallic materials such as gold (Au) and silver (Ag). , aluminum (Al), molybdenum (Mo), magnesium (Mg), etc. may be formed of two layers, but is not necessarily limited thereto.

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

The first electrode 102 may be a reflective electrode, and the second electrode 104 may be a transflective electrode.

The first light emitting unit 110 includes a first hole transporting layer (HTL) 112, a first emitting layer (EML) 114 and a first electron transporting layer (HTL) on the first electrode 102. It may include an Electron Transporting Layer (ETL) 116 .

Although not shown in the drawings, a hole injection layer (HIL) may be additionally configured on the first electrode 102 . The hole injection layer HIL 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 first charge generation layer (CGL) 140 to the first emission layer (EML) 114 .

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

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

The first hole transport layer (HTL) 112 may be formed by applying two or more layers or two or more materials. The first hole transport layer (HTL) 112 is NPD (N,N'-bis(naphthalene-1-yl)-N,N'-bis(phenyl)-2,2'-dimethylbenzidine), TPD (N, N'-bis-(3-methylphenyl)-N,N'-bis-(phenyl)-benzidine) and Spiro-TAD(2,2'7,7'tetrakis(N,N-diphenylamino)-9,9' -spirofluorene) may be made of any one or more selected from the group consisting of, 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 electron transport layer (ETL) 116 is PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole), TAZ (3-(4-biphenyl) -4-phenyl-5-tert-butylphenyl-1,2,4-triazole), BAlq(Bis(2-methyl-8-quinolinolate)-4-(phenylphenolato)aluminium), Liq(8-hydroxyquinolinolato-lithium), TPBi(2,2', 2'-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) may be formed of at least one selected from the group consisting of, but is not limited thereto.

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 114 . The hole blocking layer (HBL) prevents holes injected into the first emission layer (EML) 114 from flowing into the first electron transport layer (ETL) 116 , thereby preventing the first emission layer (EML) 114 . By improving the combination of electrons and holes in the light emitting 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 further formed under the first light emitting layer (EML) 114 . The electron blocking layer (EBL) prevents electrons injected into the first emission layer (EML) 114 from flowing into the first hole transport layer (HTL) 112 , thereby preventing the first emission layer (EML) 114 . By improving the combination of electrons and holes in the light emitting 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 light emitting layer (EML) 114 of the first light emitting unit 110 may be formed of a blue light emitting layer. The first light emitting layer (EML) 114 may include a deep blue light emitting layer or a sky blue light emitting layer in addition to a blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than that of the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The peak wavelength λmax of the first light emitting layer (EML) 114 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the first light emitting layer (EML) 114 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the first light emitting layer (EML) 114 is configured by including the auxiliary light emitting layer, the yellow-green light emitting layer or the red light emitting layer or the green light emitting layer is the first light emitting layer (EML) It is also possible to configure above or below (114).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the first light emitting layer (EML) 114 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the first emission layer (EML) 114 including the yellow-green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 114 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 114 including the green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

The host of the first light emitting layer (EML) 114 may be formed of a single material or a mixed host made of a mixed material. For example, Alq ₃ (tris(8-hydroxy-quinolino)aluminum), ADN(9,10-di(naphtha-2-yl)anthracene), BSBF(2-(9,9-spirofluoren-2-yl) -9,9-spirofluorene) material or a mixture of two or more materials, but is not limited thereto.

In addition, a dopant of the first light emitting layer (EML) 114 may be formed of a pyrene series. More specifically, the arylamine-based compound may be formed of a substituted pyrene-based compound, but is not limited thereto.

The second light emitting part 120 includes a second hole transporting layer (HTL) 122 , a second emitting layer (EML) 124 , and a second electron transporting layer (ETL) 126 . ) can be included.

Although not shown in the drawings, the second light emitting unit 120 may further include an electron injection layer (EIL) on the second electron transport layer (ETL) 126 . Also, the second light emitting unit 120 may be configured to further include a hole injection layer (HIL).

The second hole transport layer (HTL) 122 may be made of the same material as the first hole transport layer (HTL) 112 , 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.

The second electron transport layer (ETL) 126 may be made of the same material as the first electron transport layer (ETL) 116 , 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.

A hole blocking layer (HBL) may be additionally formed on the second light emitting layer (EML) 124 . The hole blocking layer (HBL) prevents holes injected into the second light emitting layer (EML) 124 from flowing into the second electron transport layer (ETL) 126 , thereby preventing the second light emitting layer (EML) 124 . By improving the coupling of electrons and holes in the light emitting layer (EML) 124 , the luminous efficiency may be improved. The second electron transport layer (ETL) 126 and the hole blocking layer HBL may be configured as one layer.

An electron blocking layer (EBL) may be further formed under the second light emitting layer (EML) 124 . The electron blocking layer (EBL) prevents electrons injected into the second emission layer (EML) 124 from flowing into the second hole transport layer (HTL) 122 , thereby preventing the second emission layer (EML) 124 . By improving the coupling of electrons and holes in the light emitting layer (EML) 124 , the luminous efficiency may be improved. The second hole transport layer (HTL) 122 and the electron blocking layer (EBL) may be configured as a single layer.

The second light emitting layer (EML) 124 of the second light emitting unit 120 may be formed of a blue light emitting layer. The second light emitting layer (EML) 124 may include a deep blue light emitting layer or a sky blue light emitting layer in addition to a blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than that of the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The peak wavelength λmax of the second light emitting layer (EML) 124 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the second light emitting layer (EML) 124 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the second light emitting layer (EML) 124 is configured by including the auxiliary light emitting layer, the yellow-green light emitting layer or the red light emitting layer or the green light emitting layer is the second light emitting layer (EML) It is also possible to configure above or below (124).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the second light emitting layer (EML) 124 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the second emission layer (EML) 124 including the yellow-green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second emission layer (EML) 124 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second emission layer (EML) 124 including the green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

The second emission layer (EML) 124 may be made of the same material as the first emission layer (EML) 114 , but is not limited thereto.

The host of the second light emitting layer (EML) 124 may be formed of a single material or a mixed host made of a mixed material. For example, Alq ₃ (tris(8-hydroxy-quinolino)aluminum), ADN(9,10-di(naphtha-2-yl)anthracene), BSBF(2-(9,9-spirofluoren- 2-yl)-9,9-spirofluorene) material or a mixture of two or more materials, but is not limited thereto.

In addition, a dopant of the second light emitting layer (EML) 124 may be formed of a pyrene series. More specifically, the arylamine-based compound may be formed of a substituted pyrene-based compound, but is not limited thereto.

A first charge generation layer (CGL) 140 may be further formed between the first light emitting unit 110 and the second light emitting unit 120 . The first charge generation layer (CGL) 140 adjusts the charge balance between the first light emitting unit 110 and the second light emitting unit 120 . The first charge generation layer 140 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) is an alkali metal such as lithium (Li), sodium (Na), potassium (K), or cesium (Cs), or magnesium (Mg), strontium (Sr), barium ( Ba) or an organic layer doped with an alkaline earth metal such as radium (Ra), but is not necessarily limited thereto.

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

In addition, the first charge generating layer (CGL) 140 may be formed as a single layer.

The third light emitting unit 130 includes a third electron transport layer (ETL) 136 , a third emitting layer (EML) 134 , and a third hole transport layer under the second electrode 104 . (HTL; Hole Transporting Layer) 132 may be included.

Although not shown in the drawings, the third light emitting part 130 may be configured to further include an electron injection layer (EIL) on the third electron transport layer (ETL) 136 . In addition, it may be configured to further include a hole injection layer (HIL; Hole Injecting Layer).

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

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

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

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

A hole blocking layer (HBL) may be additionally formed on the third light emitting layer (EML) 134 . The hole blocking layer (HBL) prevents the holes injected into the first emission layer (EML) 134 from flowing into the third electron transport layer (ETL) 136 , thereby preventing the third emission layer (EML) 134 . In this case, the luminous efficiency of the third light emitting layer (EML) 134 may be improved by improving the coupling of electrons and holes. The third electron transport layer (ETL) 136 and the hole blocking layer (HBL) may be configured as a single layer.

An electron blocking layer (EBL) may be further formed under the third light emitting layer (EML) 134 . The electron blocking layer (EBL) prevents electrons injected into the third light emitting layer (EML) 134 from flowing into the third hole transport layer (HTL) 132 , thereby preventing the third light emitting layer (EML) 134 . In this case, the luminous efficiency of the third light emitting layer (EML) 134 may be improved by improving the coupling of electrons and holes. The third hole transport layer (HTL) 132 and the electron blocking layer (EBL) may be configured as a single layer.

A second charge generation layer (CGL) 150 may be further formed between the second light emitting unit 120 and the third light emitting unit 130 . The second charge generation layer 150 adjusts the charge balance between the second light emitting unit 120 and the third light emitting unit 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 (N-CGL) serves to inject electrons into the second light-emitting unit 120 , and the P-type charge generation layer (P-CGL) is the third light-emitting unit 130 . It plays a role in injecting holes.

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

The P-type charge generation layer (P-CGL) may be formed of an organic layer including a P-type dopant, but is not limited thereto. The first charge generation layer (CGL) 140 is made of the same material as the N-type charge generation layer (N-CGL) of the second charge generation layer (CGL) 150 and the P-type charge generation layer (P-CGL) may be made, but is not necessarily limited thereto.

In addition, the second charge generating layer (CGL) 150 may be configured as a single layer.

The third light-emitting layer (EML) 134 of the third light-emitting unit 130 is a yellow-green light-emitting layer, or a green light-emitting layer, or a yellow light-emitting layer and a red light-emitting layer, Alternatively, it may be composed of one of 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 host of the third light emitting layer (EML) 134 may be formed of a single material or a mixed host made of a mixed material. For example, CBP (4,4'-bis(carbazol-9-yl)biphenyl), spiro-CBP(2,2',7,7' -tetrakis(carbazol-9-yl)-9,9' - spirobifluorene) and TcTa (4,4',4'-tris(carbazoyl-9-yl)triphenylamine), but is not necessarily limited thereto.

A dopant of the third emission layer (EML) 134 may be formed of an Iridium-based compound, but is not limited thereto.

Although the white organic light emitting diode according to the embodiment of the present invention has been described with respect to a bottom emission method, it may be applied to a top emission method or a dual emission method. In the top emission method or the positive emission method, the overall thickness of the device or the position of the light emitting layers may vary depending on the characteristics of the device.

In addition, although not shown, in the organic light emitting diode display including the organic light emitting diode according to an embodiment of the present invention, a gate line and a data line that cross each other on a substrate and define each pixel area, and extend parallel to any one of them A power supply line used is positioned, and a switching thin film transistor connected to a gate line and a data line and a driving thin film transistor connected to the switching thin film transistor are positioned in each pixel area. The driving thin film transistor is connected to the first electrode 102 .

In the present invention, the first light emitting layer (EML) 114 and the second light emitting layer (EML) in order to improve the efficiency or luminous efficiency of red, green and blue, and the color viewing angle or color gamut. It is necessary to optimize the light emitting positions of the light emitting layers constituting the 124 and the third light emitting layer (EML) 134 . This will be described with reference to FIG. 2 .

FIG. 2 is a view showing a light emitting position of the white organic light emitting diode shown in FIG. 1 .

In FIG. 2 , the horizontal axis represents the wavelength region of light, and the vertical axis represents the thickness of the organic layers. As described above, the organic layers refer to layers constituting the first light emitting unit 110 , the second light emitting unit 120 , and the third light emitting unit 130 . In FIG. 2 , the thickness of the organic layers constituting the first light emitting unit 110 , the second light emitting unit 120 , and the third light emitting unit 130 is not illustrated.

As shown in FIG. 2 , the first light emitting layer (EML) 114 constituting the first light emitting unit 110 and the second light emitting layer (EML) 124 constituting the second light emitting unit 120 are blue. ) light emitting layer, and it can be seen that the peak wavelength (λmax) of the blue light emitting layer is 440 nm to 480 nm. Regions corresponding to the peak wavelengths (λmax) of the first emission layer (EML) 114 and the second emission layer (EML) 124 are denoted by “B” in FIG. 2 .

In addition, the third light emitting layer (EML) 134 constituting the third light emitting unit 130 is a yellow-green light emitting layer, and the peak wavelength of the yellow-green light emitting layer; λmax ) is 540 nm to 575 nm. A region corresponding to a peak wavelength (λmax) of the third light emitting layer (EML) 134 is denoted by “YG” in FIG. 2 .

Therefore, light should be emitted at 440 nm to 480 nm, which is the peak wavelength (λmax) of the blue light emitting layer, and 540 nm to 575 nm, which is the peak wavelength (λ max) of the yellow-green light emitting layer. Maximum efficiency can be achieved in the white area of the contour map). Therefore, it can be seen that the light emitting layer can achieve maximum efficiency by setting the light emitting positions of the light emitting layers of the present invention to correspond to the peak wavelength of the light emitting layers. Further, since the luminous efficiency of the light emitting layer is increased, panel efficiency, color gamut, and color viewing angle can be improved.

Here, the peak wavelength (λmax) refers to the maximum wavelength of EL (ElectroLuminescence). The wavelength at which the organic material layers constituting the light emitting part emits their own light is called PL (PhotoLuminescence), and the light emitted when this PL (PhotoLuminescence) is affected by the cavity peak, which is an optical characteristic, is called EL (ElectroLuminescence). In addition, the cavity peak refers to a point at which optical transmittance is maximized, and in general, light generated between two mirrors is reflected by both mirrors (in the present invention, the second electrode is a part where the reflection is made) It is to find the part where the wavelength of light is maximized through constructive interference by controlling the thickness and the light emission position of the light emitting area. Also, as for the cavity peak, the emission peak varies according to the total thickness of the organic light emitting device, the PL of the organic material layers, and the thickness of the first electrode.

Accordingly, in the present invention, the order of the light emitting layers or the light emitting positions of the light emitting layers is set in consideration of the cavity peak and the spectral change rate of the light emitting layers. That is, in consideration of the cavity peak and the spectral change rate of the first light emitting layer, the second light emitting layer, and the third light emitting layer, the order or the light emitting position of the first light emitting layer, the second light emitting layer, and the third light emitting layer is set. The experimental results will be described with reference to FIGS. 3 to 6 and Table 1 . 3 to 6 and Table 1 are measured by constructing a bottom emission type device.

3 is a view showing light emission intensity according to a comparative example and a first embodiment of the present invention. 3 can be referred to as an EL spectrum. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

3, 5 and 6 , the comparative example includes two light emitting units including a blue light emitting layer as a first light emitting layer and a yellow-green light emitting layer as the second light emitting layer. In the embodiment, as shown in FIG. 1, the first light emitting layer and the second light emitting layer are composed of a blue light emitting layer, and the third light emitting layer is three light emitting units composed of a yellow-green light emitting layer. The light emitting part may include an electron transport layer (ETL) and a hole transport layer (HTL), and a charge generation layer (CGL) may be included between the two or three light emitting parts.

3 , a solid line indicates an Example, and a dotted line indicates a comparative example.

As shown in FIG. 3 , it can be seen that the peak wavelength (λmax) of blue in the comparative example and the first embodiment of the present invention appears in 440 nm to 480 nm. It can be seen that the emission intensity of the first embodiment of the present invention is further increased at 440 nm to 480 nm, which is the peak wavelength (λmax) of blue, compared to the comparative example.

In the comparative example, it can be seen that the peak wavelength (λmax) of yellow-green appears in 530 nm to 590 nm. It can be seen that in the first embodiment of the present invention, the peak wavelength (λmax) region is shifted to the left compared to the comparative example. That is, it can be seen that the peak wavelength (λmax) of yellow-green appears in 540 nm to 575 nm. In addition, it can be seen that in the first embodiment of the present invention, the light emission intensity of yellow-green is further increased compared to the comparative example.

In the comparative example, since yellow-green should emit light at 530 nm to 590 nm, an unnecessary light emitting area increases, so that the light emission intensity is lower than in the first embodiment. In the comparative example, since the luminous intensity is lowered, the luminous efficiency of yellow-green is lowered. Accordingly, the color viewing angle and color gamut according to the viewing angle caused by the difference in efficiency according to the emission color are lowered.

In addition, it can be seen that in the first embodiment of the present invention, the light emission intensity of yellow-green is increased compared to that of the comparative example. This is by setting the peak wavelength (λmax) of the yellow-green light emitting layer to 540 nm to 575 nm in consideration of the cavity peak of Yellow-Green and the spectral change rate according to the viewing angle, Since the unnecessary light emission area is reduced, the light emission intensity is increased. Accordingly, since the green efficiency is increased, the luminous efficiency of the yellow-green light emitting layer is increased. Accordingly, the color viewing angle and color gamut according to the viewing angle caused by the difference in efficiency according to the emission color may be improved.

In addition, since the two light emitting layers in the three light emitting units are constituted by the blue light emitting layer, the luminous efficiency of the blue light emitting layer is increased. That is, since the light emission intensity of the blue light emitting layer is increased compared to the comparative example, the light emission efficiency of the blue light emission layer is increased. Accordingly, the color viewing angle Δu'v' and the color gamut according to the viewing angle caused by the difference in efficiency according to the emission color may be improved.

And, the spectral change rate according to the viewing angle of the light emitting layer will be described with reference to FIG. 4 .

4 is a diagram illustrating a spectrum change rate according to a viewing angle according to the first embodiment of the present invention.

4 shows the measurement of light emission intensity while obliquely viewed from 0° to 15°, 30°, 45°, and 60° when viewed from the front. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

When two light emitting units having two light emitting layers of a blue light emitting layer and a yellow-green light emitting layer are configured, depending on the difference in the cavity peaks, the blue light emitting layer and the yellow-green light emitting layer are formed. -Green) The spectral change rate varies according to the viewing angle of the light emitting layer. The spectral change rate according to the viewing angle of the blue light emitting layer greatly decreases the emission intensity depending on the viewing angle, but the spectral change rate according to the viewing angle of the yellow-green light emitting layer slowly decreases the emission intensity according to the viewing angle, so the yellow- The viewing angle characteristic of the yellow-green light emitting layer is deteriorated. Therefore, in order to improve the color viewing angle characteristics, it is necessary to match the spectral change rate of blue and the yellow-green spectrum change rate. For this purpose, since the cavity peak of Yellow-Green is adjusted to a position that is shifted from the desired position, there is a problem that the efficiency of Red, Green, and Blue is reduced. do.

In the present invention, in order to match the spectral change rate of blue and yellow-green and the spectral change rate of blue, two blue light emitting layers emitting the same color in the three light emitting units are formed. placed adjacent to Since the two blue light emitting layers have two blue spectra, it is more advantageous to match the spectral change rate of yellow-green by the two blue spectra. That is, the cavity peak of the yellow-green light emitting layer may be positioned at a desired position by the two blue light emitting layers.

In addition, since the two blue light emitting layers are disposed, the difference between the rate of change of the spectrum of blue and the rate of change of the spectrum of yellow-green is almost the same, so that the color viewing angle can be improved. Here, the spectral change rate may be referred to as a spectral change rate according to the viewing angle. In addition, the spectral change rate may be referred to as a change rate of the light emission intensity according to the viewing angle.

In addition, since the two blue light emitting layers are arranged adjacently, the difference between the rate of change of the spectrum of blue and the rate of change of the spectrum of yellow-green is almost similar to the cavity peak of the blue light emitting layer ( cavity peak) and a cavity peak of the yellow-green emission layer may be located in the emission region. Here, the spectral change rate may be referred to as a spectral change rate according to the viewing angle. In addition, the spectral change rate may be referred to as a change rate of the light emission intensity according to the viewing angle.

As shown in Figure 4, it can be seen that the rate of change of the spectrum according to the viewing angle of the blue light emitting layer and the rate of change of the spectrum according to the viewing angle of yellow-green, that is, the rate of change of the emission intensity according to the viewing angle are almost similar. . Accordingly, since the rate of change of the spectral change according to the change of the viewing angle is small, the change rate of the emission intensity according to the viewing angle is small, and thus, there is no deterioration in the luminance of a specific color according to the viewing angle. Accordingly, a change in color coordinates according to the viewing angle or a color viewing angle may be reduced. In addition, since the spectral change rate according to the viewing angle is small, the viewing angle characteristic may be improved.

In addition, since the difference between the spectral change rate according to the viewing angle of the blue light emitting layer and the spectral change rate according to the viewing angle of the yellow-green light emitting layer is almost similar, the cavity peak of the blue light emitting layer and the yellow- A cavity peak of the yellow-green emission layer may be located in a desired emission region. Here, the spectral change rate may be referred to as a spectral change rate according to the viewing angle. In addition, the spectral change rate may be referred to as a change rate of the light emission intensity according to the viewing angle.

Therefore, the cavity peak of the yellow-green light emitting layer emitting a color different from the same color and the same color are obtained by the blue light emitting layers, which are two light emitting layers emitting the same color. A cavity peak of the blue light emitting layers, which are the light emitting layers, may be located in the light emitting region of the light emitting layers.

A peak wavelength (λmax) corresponding to the emission region of the two blue emission layers (EML) 114 and 124 is 440 nm to 480 nm, and a yellow-green emission layer (EML) 134 . When the peak wavelength (λmax) corresponding to the emission region of is configured to be 540 nm to 575 nm, the emission layer emits light in the desired emission region, so that unnecessary emission regions can be minimized. In addition, by setting the peak wavelength (λmax) of the yellow-green light-emitting layer to 540 nm to 575 nm, the third light-emitting layer (EML) 134 in this peak wavelength (λmax) region is Yellow-Green (Yellow). -Green) The unnecessary light emitting area of the light emitting layer is reduced. In addition, blue and green appearing when the peak wavelength λmax of the blue light emitting layer is biased to the right or when the peak wavelength λmax of the yellow-green light emitting layer is skewed to the left. ), or the color gamut or color viewing angle is reduced, can be improved.

Accordingly, since the light-emitting layers can emit light in a desired light-emitting region, the light-emitting efficiency of the light-emitting layers can be improved, and panel efficiency, color reproducibility, or color viewing angle can be improved.

As described above, since the light emission intensity of the blue light emitting layer and the yellow-green light emitting layer is increased, the light emitting efficiency of the light emitting layer is increased. In addition, the color viewing angle Δu'v' and the color gamut according to the viewing angle may be improved. This will be described with reference to Table 1 and FIGS. 5 and 6 .

Table 1 below shows the measurement of efficiency and panel efficiency according to the comparative example and the first embodiment of the present invention.

In Table 1, in Comparative Example, the first light emitting layer is a blue light emitting layer, and the second light emitting layer is two light emitting units composed of a yellow-green light emitting layer. In the embodiment, as shown in FIG. 1, the first light emitting layer and the second light emitting layer are composed of a blue light emitting layer, and the third light emitting layer is three light emitting units composed of a yellow-green light emitting layer. As described above, the light emitting part may include an electron transport layer (ETL) and a hole transport layer (HTL), and a charge generation layer (CGL) may be included between the two or three light emitting parts.

Looking at the efficiencies of red, green, blue, and white, the red efficiency was measured to be 8.0 cd/A in the comparative example, and 7.0 cd/A in the example. . The red (Red) efficiency of the comparative example and the example was measured to be similar.

In addition, the green efficiency was measured to be 29.9 cd/A in the comparative example and 38.7 cd/A in the example. As shown in FIG. 2, since the yellow-green light emitting layer is located in the desired peak wavelength (λmax) region, it can be seen that the green efficiency is improved by 29% compared to the comparative example. As the green efficiency increases, the luminous efficiency of the yellow-green light emitting layer also increases.

Blue efficiency was measured to be 2.2 cd/A in the comparative example and 3.5 cd/A in the example. It can be seen that by configuring the blue light emitting layer as the first light emitting layer and the second light emitting layer in the embodiment, the blue efficiency is improved by 59% compared to the comparative example. As the blue efficiency increases, the luminous efficiency of the blue light emitting layer also increases.

White efficiency was measured to be 72.9 cd/A in the comparative example and 85.8 cd/A in the example. It can be seen that by configuring the blue light emitting layer as the first light emitting layer and the second light emitting layer in the embodiment, white efficiency is improved by 18% compared to the comparative example.

In addition, the panel efficiency was measured to be 22.9 cd/A in the comparative example and 35.5 cd/A in the example, and it can be seen that the panel efficiency was increased by 55% compared to the comparative example.

5 is a view showing color coordinates according to a comparative example and a first embodiment of the present invention. Color coordinates are measured according to the National Television System Committee (NTSC) standard.

The color coordinates are as follows. Red was measured as (0.665, 0.330) in the comparative example, and (0.661, 0.329) in the example. Green was measured as (0.317, 0.635) in the comparative example, and (0.295, 0.649) in the example, and blue was measured as (0.142, 0.046) in the comparative example, and (0.143, 0.043) in the example. became White was measured as (0.337, 0.338) in the comparative example, and (0.285, 0.300) in the example. From this result, it can be seen that the color gamut was improved from 81.7% to 85.5% compared to the comparative example. And, since Green is located in the region of a shorter wavelength compared to the comparative example, the color gamut is improved by having a larger range of color coordinates compared to the comparative example due to the change in the color coordinates of green. .

6 is a graph showing a color viewing angle (Δu'v') according to a viewing angle. As shown in FIG. 6 , measurements were made while obliquely viewed from 0° to 15°, 30°, 45°, and 60° when viewed from the front. And, in FIG. 6, a solid line indicates an Example, and a dotted line indicates a comparative example.

It can be seen that at a viewing angle of 60° of light emitted from the organic light emitting diode, the color viewing angle (Δu'v') of the comparative example is 0.023, and that of the first embodiment is 0.016. In this embodiment, since the color viewing angle Δu'v' according to the viewing angle is small, it is possible to improve the color change rate felt by the consumer according to the viewing angle. In addition, since the color viewing angle Δu'v' of white is reduced, when implemented as an organic light emitting display device, it may be advantageous to realize the same color regardless of the viewing angle position.

In the present invention, the order of the light emitting layers or the light emitting positions of the light emitting layers is set in consideration of the cavity peak and the spectral change rate of the light emitting layers. That is, the order of the first light emitting layer, the second light emitting layer, and the third light emitting layer is set in consideration of the cavity peak and the spectral change rate of the first light emitting layer, the second light emitting layer, and the third light emitting layer. Accordingly, the two light-emitting layers emitting the same color are configured closer to the first electrode than the second electrode, and the light-emitting layers emitting a color different from the same color are configured closer to the second electrode than the first electrode. In addition, since the first light-emitting layer (EML) 114 and the second light-emitting layer (EML) 124 are formed closer to the first electrode 102 than the second electrode 104 , the blue light-emitting layers are blue. As the light emission intensity of the light emitting layer increases, the light emitting efficiency of the blue light emitting layer may be improved, and panel efficiency and color gamut or color viewing angle may be improved. In addition, since the two blue light-emitting layers are configured closer to the first electrode 102 than the second electrode 104 , the two blue light-emitting layers are formed closer to the second electrode than the first electrode 102 . 104) (referred to as "Comparative Example 1" herein), the red efficiency may be increased. This will be described with reference to Table 2, FIGS. 7 and 8 .

In Comparative Example 1, the first light emitting layer constitutes a yellow-green light emitting layer, and the second light emitting layer and the third light emitting layer are three light emitting units including a blue light emitting layer. In the embodiment, the first light emitting layer and the second light emitting layer are composed of a blue light emitting layer, and the third light emitting layer is three light emitting units composed of a yellow-green light emitting layer. The light emitting part may include an electron transport layer (ETL) and a hole transport layer (HTL), and a charge generation layer (CGL) may be included between the three light emitting parts.

As shown in Table 2, it can be seen that the red efficiency of Comparative Example 1 is 3.7 cd/A, and the red efficiency of Example 1 is 7.0 cd/A. Therefore, it can be seen that the red (Red) efficiency of the example is improved by about 90% compared to 1 in comparison. And, it can be seen that the Green efficiency of Comparative Example 1 is 44.2 cd/A, the Green efficiency of the Example is 44.3 cd/A, and the Green efficiency is similar to Comparative Example 1 and the Example. . And, it can be seen that the blue efficiency of Comparative Example 1 is 4.2 cd/A, the Blue efficiency of the Example is 4.5 cd/A, and the Blue efficiency of the Example is improved by 7% compared to Comparative Example 1. can In addition, the white efficiency of Comparative Example 1 was 82.7 cd/A and that of Example 87.7 cd/A, and it can be seen that the white efficiency of Example 1 was improved by about 6% compared to Comparative Example 1.

The panel efficiency of Comparative Example 1 was 16.3 cd/A, and that of Example was 30.8 cd/A, indicating that the panel efficiency of Example 1 was improved by about 89% compared to Comparative Example 1.

Therefore, it can be seen that when two blue light emitting layers are configured closer to the first electrode than to the second electrode, red efficiency, blue efficiency, white efficiency, and panel efficiency are increased. can In particular, it can be seen that the red efficiency is significantly increased.

7 is a view showing the light emission intensity according to Comparative Example 1 and the first embodiment of the present invention. 7 can be referred to as an EL spectrum. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum. And, in FIG. 7, Comparative Example 1 is indicated by a dotted line, and the Example is indicated by a solid line.

As shown in FIG. 7 , it can be seen that the peak wavelength (λmax) of blue in Comparative Example 1 and Example is 440 nm to 480 nm. In Example, it can be seen that the emission intensity was further increased at 440 nm to 480 nm, which is the peak wavelength (λmax) of blue, as compared with Comparative Example 1.

In Comparative Example 1, it can be seen that the peak wavelength (λmax) of yellow-green appears in 530 nm to 590 nm. And, in the embodiment, it can be seen that the peak wavelength (λmax) of yellow-green appears in 540 nm to 575 nm. In Example and Comparative Example 1, it can be seen that the emission intensity of yellow-green is similar.

And, it can be seen that in Comparative Example 1 and Examples, the peak wavelength (λ max ) of red appears in 600 nm to 650 nm. In Example 1, it can be seen that the emission intensity was further increased at 600 nm to 650 nm, which is the peak wavelength (λmax) of the red (Blue) emission layer compared to Comparative Example 1.

The color viewing angle Δu'v' according to the viewing angle will be described with reference to FIG. 8 .

8 is a graph showing a color viewing angle (Δu'v') according to a viewing angle. As shown in FIG. 8 , measurements were made while obliquely viewed from 0° to 15°, 30°, 45°, and 60° when viewed from the front. And, in FIG. 8, Comparative Example 1 is indicated by a dotted line, and the Example is indicated by a solid line.

It can be seen that at a viewing angle of 60° of light emitted from the organic light emitting diode, the color viewing angle (Δu'v') of Comparative Example 1 was 0.100, and that of Example was 0.016. In this embodiment, since the color viewing angle Δu'v' according to the viewing angle is small, it is possible to improve the color change rate felt by the consumer according to the viewing angle. In addition, since the color viewing angle Δu'v' of white is reduced, when implemented as an organic light emitting display device, it may be advantageous to realize the same color regardless of the viewing angle position.

Therefore, when the two blue light emitting layers are configured closer to the first electrode than to the second electrode, the intensity of red light emission increases, so that the color viewing angle according to the viewing angle caused by the difference in efficiency according to the emission color and Color gamut can be improved.

However, it is also possible to apply the structure of Comparative Example 1 when designing the organic light emitting device with a structure capable of increasing red efficiency.

In the embodiment of the present invention, three light emitting units have been described as an example, but at least three light emitting units may be configured, and at least two light emitting units among the three or more light emitting units may be configured as light emitting units emitting the same color. By configuring the two light emitting units emitting the same color closer to the first electrode than to the second electrode, the light emitting efficiency of the light emitting layer may be improved, and color viewing angle or color gamut according to panel efficiency and viewing angle may be improved.

9 is a schematic cross-sectional view illustrating a white organic light emitting diode according to a second exemplary embodiment of the present invention. Hereinafter, in describing the present embodiment, a description of the same or corresponding components as in the previous embodiment will be omitted.

The white organic light emitting diode 200 illustrated in FIG. 9 includes first and second electrodes 202 and 204 on a substrate 201 , a first light emitting part 210 between the first and second electrodes 202 and 204 , and a second A light emitting unit 220 and a third light emitting unit 230 are provided.

The first electrode 202 is an anode for supplying holes, and may be formed of gold (Au), silver (Ag), aluminum (Al), molybdenum (Mo), magnesium (Mg), etc., or an alloy thereof. , but is not necessarily limited thereto.

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

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

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

In the second embodiment of the present invention, the position of the first electrode 202 from the second electrode 204 , the first light emitting layer of the first light emitting part 210 , and the second of the second light emitting part 220 . By setting the light emission positions of the second light emitting layer and the third light emitting layer of the third light emitting unit 230 , light emitting efficiency and color viewing angle may be improved.

The position L0 of the first electrode 202 is set to be 500 nm to 600 nm from the second electrode 204 . Alternatively, the position L0 of the first electrode 202 is set to be located within a range of 500 nm to 600 nm from the reflective surface of the second electrode 204 . And, the emission peak of the light emitting layer constituting the first light emitting unit 210, the second light emitting unit 220, and the third light emitting unit 230 is located at a specific wavelength, and the light of the specific wavelength It is possible to improve the luminous efficiency by emitting light. In addition, the first light emitting unit 210 , the second light emitting unit 220 , and the third light emitting unit 230 have a maximum emission range in the light emitting region of the first light emitting layer, the second light emitting layer, and the third light emitting layer. can have

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 . 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) is formed by the second electrode ( 204 serves to inject electrons into the third electron transport layer (ETL) 236 .

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

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

A hole injection layer (HIL) may be further formed under the third hole transport layer (HTL) 232 .

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

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

The third light-emitting layer (EML) 234 is a yellow-green light-emitting layer, or a 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. Green) light emitting layer, or a yellow-green light emitting layer and a red light emitting layer may be composed of one or a combination thereof. When a red light emitting layer is further formed on the yellow-green light emitting layer, the efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light-emitting layer and the red light-emitting layer, or the red light-emitting layer and the green light-emitting layer, or the yellow-green light-emitting layer and the red light-emitting layer is the third light-emitting layer ( It is also possible to configure above or below the EML) 234 . 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 is the third light-emitting layer ( EML) 234 above and below the same configuration or may be configured differently.

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

In addition, the peak wavelength λmax of the red light emitting layer may be in a range of 600 nm to 650 nm. A peak wavelength (λmax) of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, the peak wavelength λmax of the red light emitting layer and the green light emitting layer may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region. When it is composed of two layers, the red light emitting layer and the green light emitting layer, color gamut can be improved.

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

In addition, the third light emitting layer (EML) 234 of the third light emitting unit 230 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, depending on the characteristics or structure of the device. can do. A peak wavelength (λmax) of the red light emitting layer may be in a range of 600 nm to 650 nm. The peak wavelength (λmax) of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When the red light emitting layer is composed of two layers, the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength λmax of the third light emitting layer (EML) 234 may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The third light-emitting layer (EML) 234 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 yellow- When composed of one of a yellow-green light-emitting layer and a red light-emitting layer or a combination thereof, a peak wavelength of the third light-emitting layer (EML) 234 is in the range of 510 nm to 650 nm. can be done with Here, the peak wavelength may be an emission region.

The peak wavelength (λmax) of the yellow-green light emitting layer may be in the range of 540 nm to 575 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L1 of the third light emitting layer (EML) 234 is 20 nm from the second electrode 204 so that the luminous efficiency and the color viewing angle or color gamut of the third light emitting layer (EML) 234 are improved. to 80 nm. Alternatively, the emission position L1 of the third emission layer (EML) 234 may be set to be located within a range of 20 nm to 80 nm from the reflective surface of the second electrode 204 .

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

Although not shown in the drawings, the second light emitting unit 220 may further include an electron injection layer (EIL) on the second electron transport layer (ETL) 226 .

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

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

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

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

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

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

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

The second light emitting layer (EML) 224 may be formed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than that of the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The peak wavelength λmax of the second light emitting layer (EML) 224 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the first light emitting layer (EML) 224 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. The compensator auxiliary light emitting layer may be composed of one of a yellow-green light emitting layer, a red light emitting layer, a green light emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the second light emitting layer (EML) 224 is configured by including the auxiliary light emitting layer, the yellow-green light emitting layer or the red light emitting layer or the green light emitting layer is the second light emitting layer (EML) It is also possible to configure above or below (224).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the second light emitting layer (EML) 224 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the second light emitting layer (EML) 224 including the yellow-green light emitting layer that is the auxiliary light emitting layer may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second emission layer (EML) 224 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second light emitting layer (EML) 224 including the green light emitting layer, which is the auxiliary light emitting layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L2 of the second light emitting layer (EML) 224 is 150 nm away from the second electrode 204 so that the light emitting efficiency and the color viewing angle or color gamut of the second light emitting layer (EML) 224 are improved. to 200 nm. Alternatively, the light emission position L2 of the second light emitting layer (EML) 224 may be set to be located within a range of 150 nm to 200 nm from the reflective surface of the second electrode 204 .

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 generating layer (CGL) 250 adjusts the charge balance 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). In addition, the second charge generating layer (CGL) 150 may be configured as a single layer.

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

Although not shown in the drawings, a hole injection layer (HIL) may be additionally formed on the first electrode 202 .

In the first light emitting layer (EML) 214 , holes supplied through the first hole transport layer (HTL) 212 and electrons supplied through the first electron transport layer (ETL) 216 recombine. Thus, light is generated.

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

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

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 214 . The 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 further formed under the first light emitting layer (EML) 214 . The first hole transport layer (HTL) 212 and the electron blocking layer (EBL) may be configured as a single layer.

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 generating layer (CGL) 240 adjusts the charge balance between the first light emitting unit 210 and the second light emitting unit 220 . The first charge generation layer 240 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL). In addition, the first charge generating layer (CGL) 240 may be configured as a single layer.

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

The peak wavelength λmax of the first light emitting layer (EML) 214 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the first light emitting layer (EML) 214 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the first light emitting layer (EML) 214 is configured by including the auxiliary light emitting layer, the yellow-green light emitting layer or the red light emitting layer or the green light emitting layer is the first light emitting layer (EML) It is also possible to configure above or below (214).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the first light emitting layer (EML) 214 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the first emission layer (EML) 214 including the yellow-green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 214 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 114 including the green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L3 of the first light emitting layer (EML) 214 is 270 nm away from the second electrode 204 so that the light emitting efficiency and the color viewing angle or color gamut of the first light emitting layer (EML) 214 are improved. It can be set to be located within the range of to 330 nm. Alternatively, the emission position L3 of the first emission layer (EML) 214 may be set to be located within a range of 270 nm to 330 nm from the reflective surface of the second electrode 204 .

The structure shown in FIG. 9 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.

Light emitting positions of the light emitting layers of the organic light emitting device to which the structure shown in FIG. 9 is applied will be described with reference to FIG. 10 .

10 is a diagram illustrating a light emitting position of an organic light emitting diode according to a second exemplary embodiment of the present invention.

That is, in FIG. 10 , the horizontal axis indicates the wavelength region of light, and the vertical axis indicates the emission positions of the emission layers constituting the emission unit from the second electrode 204 , which may be referred to as a contour map. Here, the light emitting positions of the light emitting layers of the present invention are shown except for the first electrode 202 and the second electrode 204 .

Since the third light emitting layer (EML) 234 constituting the third light emitting part 230 is a yellow-green light emitting layer, the peak wavelength (λmax) range of the third light emitting layer (EML) 234 . may be in the range of 540 nm to 575 nm.

Accordingly, by setting the emission position of the third emission layer (EML) 234 to be in the range of 20 nm to 80 nm, the emission peak 234E corresponding to the emission region of the third emission layer (EML) 234 is the The third light emitting layer (EML) 234 is positioned at a peak wavelength λmax of 540 nm to 575 nm. Accordingly, by allowing the yellow-green light emitting layer to emit light in a range of 540 nm to 575 nm, maximum efficiency can be achieved in a white region of a contour map.

In addition, the third light emitting layer (EML) 234 of the third light emitting unit 230 may be composed of two layers, a yellow light emitting layer and a red light emitting layer, depending on the characteristics or structure of the device. The peak wavelength (λmax) of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. A peak wavelength (λmax) of the emission region of the red emission layer may be in a 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 when light is emitted in the emission region of 540 nm to 650 nm, which is the emission region of the third emission layer (EML) 234 .

In addition, the third light emitting layer (EML) 234 of the third light emitting unit 230 may be composed 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 λmax of the emission region of the red emission layer may be in a range of 600 nm to 650 nm. The peak wavelength λmax 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 when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 234 .

In addition, the third light emitting layer (EML) 234 of the third light emitting unit 230 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, depending on the characteristics or structure of the device. can do. The peak wavelength λmax of the emission region of the red emission layer may be in a range of 600 nm to 650 nm. The peak wavelength (λmax) 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 when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 234 .

Accordingly, as the third light-emitting layer (EML) 234 , 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 When one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof is configured, the peak wavelength of the light emitting region of the third light emitting layer (EML) 234 (λmax) range may be in the range of 510 nm to 650 nm. In this case, maximum efficiency can be achieved in the white region of the contour map when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 234 .

Since the second light emitting layer (EML) 224 constituting the second light emitting unit 220 is a blue light emitting layer, the peak wavelength (λmax) range of the light emitting region of the second light emitting layer (EML) 224 is It may range from 440 nm to 480 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Accordingly, by setting the emission position of the second emission layer (EML) 224 to be in the range of 150 nm to 200 nm, the emission peak 224E corresponding to the emission region of the second emission layer (EML) 224 is the The second light emitting layer (EML) 224 is positioned at a peak wavelength λmax of 440 nm to 480 nm. Accordingly, by allowing the blue light emitting layer to emit light in a range of 440 nm to 480 nm, maximum efficiency can be achieved in a white region of a contour map.

In addition, as the second light emitting layer (EML) 224 , 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 green (Green) In the case of one of the emission layers or a combination thereof, the peak wavelength λmax of the emission region of the second emission layer (EML) 224 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Since the first light emitting layer (EML) 214 constituting the first light emitting part 210 is a blue light emitting layer, the peak wavelength (λmax) range of the light emitting region of the first light emitting layer (EML) 214 is It may range from 440 nm to 480 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Accordingly, by setting the emission position of the first emission layer (EML) 214 in the range of 270 nm to 330 nm, the emission peak 214E corresponding to the emission region of the first emission layer (EML) 214 is the The peak wavelength λmax of the first light emitting layer (EML) 214 is 440 nm to 480 nm. Accordingly, by allowing the blue light emitting layer to emit light in a range of 440 nm to 480 nm, maximum efficiency can be achieved in a white region of a contour map.

In addition, as the first light emitting layer (EML) 214 , 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 green (Green) In the case of one of the emission layers or a combination thereof, the peak wavelength (λmax) range of the emission region of the first emission layer (EML) 214 may be in the range of 440 nm to 650 nm. . The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

As described above, light is emitted at 440 nm to 480 nm, which is the peak wavelength (λmax) of the blue light emitting layer, and 540 nm to 575 nm, which is the peak wavelength (λ max) of the yellow-green light emitting layer. In this way, maximum efficiency can be achieved in the white region of the contour map. Therefore, it can be seen that the light emitting layer can achieve maximum efficiency by setting the light emitting positions of the light emitting layers of the present invention to correspond to the peak wavelength of the light emitting layers. Further, since the luminous efficiency of the light emitting layer is increased, panel efficiency, color gamut, and color viewing angle can be improved.

11 is a diagram illustrating light emission intensity according to a second embodiment of the present invention. 11 can be referred to as an EL spectrum.

In FIG. 11 , the horizontal axis represents the wavelength region of light, and the vertical axis represents light emission intensity. The emission intensity is a numerical value expressed as a relative value based on the maximum value of the EL spectrum.

11 , the embodiment (minimum position) is a portion set as the minimum position when the emission positions of the emission layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the minimum position is set to 20 nm.

The embodiment (maximum position) is a portion set to the maximum position when the light emitting positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the maximum position is set to 80 nm.

The embodiment (optimal position) is the portion set as the light emitting position in the embodiment of the present invention. For example, when the light emission position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the light emission position in the embodiment is set in the range of 20 nm to 80 nm. will be.

As shown in FIG. 11, when the minimum position of the light emitting position of the present invention is deviated, the optimal position is compared with the following. It can be seen that the emission intensity is decreased in the range of 440 nm to 480 nm, which is the range of the peak wavelength (λmax) of blue light. In addition, it can be seen that the emission intensity decreases in the range of 540 nm to 575 nm, which is the range of the peak wavelength (λmax) of yellow-green light. In addition, it can be seen that the emission intensity is remarkably reduced in the range of 600 nm to 650 nm of the peak wavelength (λmax) of red light.

And, when the light emitting position of the present invention is out of the maximum position, it is compared with the optimal position as follows. It can be seen that the emission intensity is reduced in the range of 440 nm to 480 nm of the peak wavelength of blue light. In addition, it can be seen that the emission intensity decreases in the range of 540 nm to 575 nm, which is the range of the peak wavelength (λmax) of yellow-green light.

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

12 is a graph showing a color viewing angle (Δu'v') according to a viewing angle. As shown in FIG. 12 , measurements were made while obliquely viewed from 0° to 15°, 30°, 45°, and 60° when viewed from the front.

12 , the embodiment (minimum position) is a portion set as the minimum position when the emission positions of the emission layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the minimum position is set to 20 nm.

The embodiment (maximum position) is a portion set to the maximum position when the light emitting positions of the light emitting layers are set. For example, when the light emitting position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the maximum position is set to 80 nm.

The embodiment (optimal position) is the portion set as the light emitting position in the embodiment of the present invention. For example, when the light emission position L1 of the third light emitting layer (EML) 234 is in the range of 20 nm to 80 nm from the second electrode 204, the light emission position in the embodiment is set in the range of 20 nm to 80 nm. will be.

As shown in FIG. 12 , when the minimum position of the light emitting position of the present invention is deviated, the optimal position is compared with the following. When the optimal position of the present invention is set, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of the light emitted from the organic light emitting diode. In addition, it can be seen that, when out of the minimum position, the color viewing angle Δu'v' at a viewing angle of 60° of light emitted from the organic light emitting diode is 0.050. Accordingly, when the color viewing angle Δu'v' is greater than or equal to 0.050 when it deviates from the minimum position, a color change rate or color viewing angle defect according to an angle on the screen of the organic light emitting display device occurs. Accordingly, the consumer can sense the color change according to the viewing angle.

And, when the light emitting position of the present invention is out of the maximum position, it is compared with the optimal position as follows. When the optimal position of the present invention is set, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of the light emitted from the organic light emitting diode. In addition, it can be seen that the color viewing angle Δu'v' is 0.070 at a viewing angle of 60° of light emitted from the organic light emitting device when it is out of the maximum position. Accordingly, when the color viewing angle Δu'v' is greater than or equal to 0.070 when it is out of the minimum position, a color change rate or color viewing angle defect according to an angle on the screen of the organic light emitting display device occurs. Accordingly, the consumer can sense the color change according to the viewing angle.

Therefore, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of light emitted from the organic light emitting device of the present invention when it is set to the optimal position of the present invention rather than when it is set to the minimum or maximum position of the embodiment. there is. In this embodiment, since the color viewing angle Δu'v' according to the viewing angle is small, it is possible to improve the color change rate felt by the consumer according to the viewing angle. In addition, since the color viewing angle Δu'v' of white is reduced, when implemented as an organic light emitting display device, it may be advantageous to realize the same color regardless of the viewing angle position. In addition, it is possible to improve the color change rate or color viewing angle defect according to the angle of the screen of the organic light emitting display device.

In addition, light emission positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer may be set to improve luminous efficiency and color viewing angle in consideration of the spectral change rate and cavity peak of the light emitting layers.

The position of the first electrode may be in a range of 500 nm to 600 nm from the second electrode.

A light emission position of the third light emitting layer may be in a range of 20 nm to 80 nm from the second electrode.

An emission position of the second emission layer may be in a range of 150 nm to 200 nm from the second electrode.

An emission position of the first emission layer may be in a range of 270 nm to 330 nm from the second electrode.

A color viewing angle (Δu'v') at a viewing angle of 60° of light emitted from the organic light emitting diode may be 0.016 or less.

13 is a diagram illustrating a white organic light emitting diode according to a third exemplary embodiment of the present invention. In describing the present embodiment, a description of the same or corresponding components as in the previous embodiment will be omitted.

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

The first electrode 302 and the second electrode 304 may be referred to as an anode or a cathode, respectively.

The first electrode 302 may be a reflective electrode, and the second electrode 304 may be a transflective electrode.

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

In the third embodiment of the present invention, the position of the second electrode 304 from the first electrode 302 , the first light emitting layer of the first light emitting part 310 , and the second of the second light emitting part 320 . By setting the light emitting position of the second light emitting layer and the third light emitting layer of the third light emitting unit 330 , light emitting efficiency and color viewing angle or color gamut may be improved.

The position L0 of the second electrode 304 is set to be 500 nm to 600 nm from the first electrode 302 . Alternatively, the position L0 of the second electrode 304 is set to be located within a range of 500 nm to 600 nm from the interface between the substrate 301 and the first electrode 302 . And, the emission peak of the light emitting layer constituting the first light emitting unit 310, the second light emitting unit 320, and the third light emitting unit 330 is located at a specific wavelength, and the light of the specific wavelength It is possible to improve the luminous efficiency by emitting light. In addition, the first light emitting unit 310 , the second light emitting unit 320 , and the third light emitting unit 330 have a maximum emission range in the light emitting region of the first light emitting layer, the second light emitting layer, and the third light emitting layer. can have

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

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

The first hole transport layer (HTL) 312 may be formed by applying two or more layers or two or more materials.

The first electron transport layer (ETL) 316 may be formed by applying two or more layers or two or more materials.

A hole blocking layer (HBL) may be additionally formed on the first light emitting layer (EML) 214 . The first electron transport layer (ETL) 316 and the hole blocking layer (HBL) may be configured as a single layer.

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

The first light emitting layer (EML) 314 may be formed of a blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. Since the deep blue light emitting layer is located in a shorter wavelength region than that of the blue light emitting layer, it may be advantageous to improve color reproducibility and luminance.

The peak wavelength λmax of the first light emitting layer (EML) 314 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the first light emitting layer (EML) 314 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the first light emitting layer (EML) 314 is configured by including the auxiliary light emitting layer, the yellow-green light emitting layer or the red light emitting layer or the green light emitting layer is the first light emitting layer (EML) It is also possible to configure above or below (314).

In addition, as the auxiliary light emitting layer, a yellow-green or red light emitting layer or a green light emitting layer may be configured identically or differently above and below the first light emitting layer (EML) 314 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the first light emitting layer (EML) 314 including the yellow-green light emitting layer that is the auxiliary light emitting layer may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 314 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the first emission layer (EML) 314 including the green emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L1 of the first light emitting layer (EML) 314 is 100 nm from the first electrode 302 so that the light emitting efficiency and the color viewing angle or color gamut of the first light emitting layer (EML) 314 are improved. to 150 nm. Alternatively, the emission position L1 of the first emission layer (EML) 314 may be set to be located within a range of 100 nm to 150 nm from the interface between the substrate 301 and the first electrode 302 .

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

Although not shown in the drawings, the second light emitting unit 320 may further include an electron injection layer (EIL) on the second electron transport layer (ETL) 326 .

The second electron transport layer (ETL) 326 may be formed by applying two or more layers or two or more materials.

The second hole transport layer (HTL) 322 may be formed by applying two or more layers or two or more materials.

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

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

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

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

The peak wavelength λmax of the second light emitting layer (EML) 324 may be in a range of 440 nm to 480 nm. Here, the peak wavelength may be an emission region.

Alternatively, the second light emitting layer (EML) 324 may include an auxiliary light emitting layer capable of emitting a color different from that of the blue light emitting layer. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. The auxiliary light-emitting layer may be formed of one of a yellow-green light-emitting layer, a red light-emitting layer, or a green light-emitting layer, or a combination thereof. When the auxiliary light emitting layer is further configured, the luminous efficiency of the green light emitting layer or the red light emitting layer can be further improved. When the second light-emitting layer (EML) 324 is configured by including the auxiliary light-emitting layer, the yellow-green light-emitting layer or the red light-emitting layer or the green light-emitting layer is the second light-emitting layer (EML) It is also possible to configure above or below (324).

In addition, as the auxiliary light-emitting layer, a yellow-green or red light-emitting layer or a green light-emitting layer may be configured identically or differently above and below the second light-emitting layer (EML) 324 . there is. The position or number of the light emitting layers may be selectively disposed according to the configuration and characteristics of the device, but is not necessarily limited thereto.

The peak wavelength λmax of the second light emitting layer (EML) 324 including the yellow-green light emitting layer that is the auxiliary light emitting layer may be in a range of 440 nm to 590 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second emission layer (EML) 324 including the red emission layer, which is the auxiliary emission layer, may be in a range of 440 nm to 650 nm. Here, the peak wavelength may be an emission region. In addition, the peak wavelength λmax of the second light-emitting layer (EML) 324 including the green light-emitting layer, which is the auxiliary light-emitting layer, may be in a range of 440 nm to 570 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L2 of the second light emitting layer (EML) 324 is 240 nm away from the first electrode 302 so that the light emitting efficiency and the color viewing angle or color gamut of the second light emitting layer (EML) 324 are improved. to 280 nm. Alternatively, the emission position L2 of the second emission layer (EML) 324 may be set to be located within a range of 240 nm to 280 nm from the interface between the substrate 301 and the second electrode 302 .

A first charge generating layer (CGL) 340 may be further formed between the first light emitting part 310 and the second light emitting part 320 . The first charge generating layer (CGL) 340 adjusts the charge balance between the first light emitting part 310 and the second light emitting part 320 . The first charge generation layer 340 may include an N-type charge generation layer (N-CGL) and a P-type charge generation layer (P-CGL). In addition, the first charge generating layer (CGL) 340 may be configured as a single layer.

The third light emitting part 330 includes a third electron transport layer (ETL) 336 , a third light emitting layer (EML) 334 , and a third hole transport layer (HTL 332 ) under the second electrode 304 . Although not shown in the drawings, an electron injection layer (EIL) may be additionally formed on the third electron transport layer (ETL) 336 .

The third electron transport layer (ETL) 336 may be formed by applying two or more layers or two or more materials.

The third hole transport layer (HTL) 332 may be formed by applying two or more layers or two or more materials.

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

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

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

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 generating layer (CGL) 350 adjusts the charge balance between the second and third light emitting units 320 and 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). In addition, the second charge generating layer (CGL) 350 may be configured as a single layer.

The third light-emitting layer (EML) 334 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 yellow- It may be composed of one of a yellow-green light-emitting layer and a red light-emitting layer, or a combination thereof. When a red light emitting layer is further formed on the yellow-green light emitting layer, the efficiency of the red light emitting layer may be further improved. The red light emitting layer may be formed above or below the yellow-green light emitting layer. And, the yellow light-emitting layer and the red light-emitting layer, or the red light-emitting layer and the green light-emitting layer, or the yellow-green light-emitting layer and the red light-emitting layer is the third light-emitting layer ( It is also possible to configure above or below the EML) 334 . 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 is the third light-emitting layer ( EML) 334 above and below may be configured identically or differently.

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

In addition, the peak wavelength λmax of the red light emitting layer may be in a range of 600 nm to 650 nm. A peak wavelength of the green light emitting layer may be in the range of 510 nm to 560 nm. Accordingly, the peak wavelength λmax of the red light emitting layer and the green light emitting layer may be in the range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region. When it is composed of two layers, the red light emitting layer and the green light emitting layer, color gamut can be improved.

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

In addition, the third light emitting layer (EML) 334 of the third light emitting unit 330 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, depending on the characteristics or structure of the device. can do. A peak wavelength (λmax) of the red light emitting layer may be in a range of 600 nm to 650 nm. The peak wavelength (λmax) of the yellow-green light emitting layer may be in the range of 510 nm to 580 nm. When the red light emitting layer is composed of two layers, the red light emitting layer and the yellow-green light emitting layer, the luminous efficiency of the red light emitting layer can be increased. In this case, the peak wavelength λmax of the third light emitting layer (EML) 334 may be in a range of 510 nm to 650 nm. Here, the peak wavelength may be an emission region.

The third light-emitting layer (EML) 334 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 yellow- When composed of one of a yellow-green light-emitting layer and a red light-emitting layer or a combination thereof, the peak wavelength λmax of the third light-emitting layer (EML) 334 is in the range of 510 nm to 650 nm. can do. Here, the peak wavelength may be an emission region.

The peak wavelength (λmax) of the yellow-green light emitting layer may be in the range of 540 nm to 575 nm. Here, the peak wavelength may be an emission region.

Accordingly, the light emitting position L3 of the third light emitting layer (EML) 334 is 370 nm from the first electrode 302 so as to improve the luminous efficiency, color viewing angle, or color gamut of the third light emitting layer (EML) 334 . to 410 nm. Alternatively, the emission position L3 of the third emission layer (EML) 334 may be set to be located within a range of 370 nm to 410 nm from the interface between the substrate 301 and the first electrode 302 .

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 organic light emitting device, but is not limited thereto.

Light emitting positions of the light emitting layers of the organic light emitting device to which the structure shown in FIG. 13 is applied will be described with reference to FIG. 14 .

14 is a diagram illustrating a light emitting position of an organic light emitting diode according to a third exemplary embodiment of the present invention.

That is, in FIG. 14 , the horizontal axis indicates the wavelength region of light, and the vertical axis indicates emission positions of the emission layers constituting the emission unit from the second electrode 204 , which may be referred to as a contour map. Here, the light emitting positions of the light emitting layers of the present invention are shown except for the first electrode 302 and the second electrode 304 .

Since the first light emitting layer (EML) 314 constituting the first light emitting part 310 is a blue light emitting layer, the peak wavelength (λmax) range of the light emitting region of the first light emitting layer (EML) 314 is It may range from 440 nm to 480 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

In addition, as the first light emitting layer (EML) 314 , 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 green (Green) In the case of one of the emission layers or a combination thereof, the peak wavelength λmax of the emission region of the first emission layer (EML) 314 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Accordingly, by setting the emission position of the first emission layer (EML) 314 in the range of 100 nm to 150 nm, the emission peak 314E corresponding to the emission region of the first emission layer (EML) 314 is the The peak wavelength λmax of the first light emitting layer (EML) 314 is 440 nm to 480 nm. Accordingly, by allowing the blue light emitting layer to emit light in a range of 440 nm to 480 nm, maximum efficiency can be achieved in a white region of a contour map.

The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Since the second light emitting layer (EML) 324 constituting the second light emitting part 320 is a blue light emitting layer, the peak wavelength λmax of the light emitting region of the second light emitting layer (EML) 324 is It may range from 440 nm to 480 nm.

Accordingly, by setting the emission position of the second emission layer (EML) 324 in the range of 240 nm to 280 nm, the emission peak 324E corresponding to the emission region of the second emission layer (EML) 324 is the The peak wavelength λmax of the second light emitting layer (EML) 324 is 440 nm to 480 nm. Accordingly, by allowing the blue light emitting layer to emit light in a range of 440 nm to 480 nm, maximum efficiency can be achieved in a white region of a contour map. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

In addition, as the second light emitting layer (EML) 324 , 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 green (Green) In the case of one of the emission layers or a combination thereof, the peak wavelength λmax of the emission region of the second emission layer (EML) 324 may be in the range of 440 nm to 650 nm. The blue light emitting layer may include one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer.

Since the third light emitting layer (EML) 334 constituting the third light emitting part 330 is a yellow-green light emitting layer, the peak wavelength (λmax) range of the third light emitting layer (EML) 234 . may be in the range of 540 nm to 575 nm.

Accordingly, by setting the emission position of the third emission layer (EML) 334 in the range of 370 nm to 410 nm, the emission peak 334E corresponding to the emission region of the third emission layer (EML) 334 is the The third light emitting layer (EML) 334 is positioned at a peak wavelength λmax of 540 nm to 575 nm. Accordingly, by allowing the yellow-green light emitting layer to emit light in a range of 540 nm to 575 nm, maximum efficiency can be achieved in a white region of a contour map.

In addition, the third light emitting layer (EML) 334 of the third light emitting unit 330 may be composed of two layers, a yellow light emitting layer and a red light emitting layer, depending on the characteristics or structure of the device. The peak wavelength (λmax) of the emission region of the yellow emission layer may be in the range of 540 nm to 580 nm. A peak wavelength (max) of the emission region of the red emission layer may be in a 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 when light is emitted in the emission region of 540 nm to 650 nm, which is the emission region of the third emission layer (EML) 334 .

In addition, the third light emitting layer (EML) 334 of the third light emitting unit 330 may include 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 λmax of the emission region of the red emission layer may be in a range of 600 nm to 650 nm. The peak wavelength λmax 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 when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 334 .

In addition, the third light emitting layer (EML) 334 of the third light emitting unit 330 is composed of two layers, a red light emitting layer and a yellow-green light emitting layer, depending on the characteristics or structure of the device. can do. The peak wavelength λmax of the emission region of the red emission layer may be in a range of 600 nm to 650 nm. The peak wavelength (λmax) 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 when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 334 .

Accordingly, as the third light-emitting layer (EML) 334 , 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 When one of a yellow-green light emitting layer and a red light emitting layer or a combination thereof is configured, the peak wavelength λmax of the light emitting region of the third light emitting layer (EML) 334 is 510 nm to 650 nm. In this case, maximum efficiency can be achieved in the white region of the contour map when light is emitted in the emission region of 510 nm to 650 nm, which is the emission region of the third emission layer (EML) 334 .

As described above, light is emitted at 440 nm to 480 nm, which is the peak wavelength (λmax) of the blue light emitting layer, and 540 nm to 575 nm, which is the peak wavelength (λ max) of the yellow-green light emitting layer. In this way, maximum efficiency can be achieved in the white region of the contour map. Therefore, it can be seen that the light emitting layer can achieve maximum efficiency by setting the light emitting positions of the light emitting layers of the present invention to correspond to the peak wavelength of the light emitting layers. Further, since the luminous efficiency of the light emitting layer is increased, panel efficiency, color gamut, and color viewing angle can be improved.

15 is a diagram illustrating light emission intensity according to a third embodiment of the present invention. 15 can be referred to as an EL spectrum.

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

In FIG. 15 , the embodiment (minimum position) is a portion set as 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) 314 is in the range of 100 nm to 150 nm from the first electrode 302 , the minimum position is set to 100 nm.

The embodiment (maximum position) is a portion set to the maximum position when the light emitting positions of the light emitting layers are set. For example, when the emission position L1 of the first emission layer (EML) 314 is in the range of 100 nm to 150 nm from the first electrode 302 , the maximum position is set to 150 nm.

The embodiment (optimal position) is the portion set as the light emitting position in the embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 100 nm to 150 nm from the first electrode 302, the light emission position of the embodiment is set in the range of 100 nm to 150 nm. will be.

As shown in FIG. 15 , when the minimum position of the light emitting position of the present invention is deviated, the optimal position is compared with the following. It can be seen that the emission intensity is decreased in the range of 440 nm to 480 nm, which is the range of the peak wavelength (λmax) of blue light. In addition, it can be seen that the emission intensity decreases in the range of 540 nm to 575 nm, which is the range of the peak wavelength (λmax) of yellow-green light. In addition, it can be seen that the emission intensity is remarkably reduced in the range of 600 nm to 650 nm of the peak wavelength (λmax) of red light.

And, when the light emitting position of the present invention is out of the maximum position, it is compared with the optimal position as follows. It can be seen that the emission intensity is decreased in the range of 440 nm to 480 nm, which is the range of the peak wavelength (λmax) of blue light. In addition, it can be seen that the emission intensity decreases in the range of 540 nm to 575 nm, which is the range of the peak wavelength (λmax) of yellow-green light.

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

16 is a graph showing a color viewing angle (Δu'v') according to a viewing angle. As shown in FIG. 16 , measurements were made while obliquely viewed from 0° to 15°, 30°, 45°, and 60° when viewed from the front.

In FIG. 16 , the embodiment (minimum position) is a portion set as 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) 314 is in the range of 100 nm to 150 nm from the first electrode 302 , the minimum position is set to 100 nm.

The embodiment (maximum position) is a portion set to the maximum position when the light emitting positions of the light emitting layers are set. For example, when the emission position L1 of the first emission layer (EML) 314 is in the range of 100 nm to 150 nm from the first electrode 302 , the maximum position is set to 150 nm.

The embodiment (optimal position) is the portion set as the light emitting position in the embodiment of the present invention. For example, when the light emitting position L1 of the first light emitting layer (EML) 314 is in the range of 100 nm to 150 nm from the first electrode 302, the light emission position of the embodiment is set in the range of 100 nm to 150 nm. will be.

As shown in FIG. 16 , when the minimum position of the light emitting position of the present invention is deviated, the optimal position is compared with the following. When the optimal position of the present invention is set, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of the light emitted from the organic light emitting diode. In addition, it can be seen that, when out of the minimum position, the color viewing angle Δu'v' at a viewing angle of 60° of the light emitted from the organic light emitting diode is 0.070. Accordingly, when the color viewing angle Δu'v' is greater than or equal to 0.070 when it is out of the minimum position, a color change rate or color viewing angle defect according to an angle on the screen of the organic light emitting display device occurs. Accordingly, the consumer can sense the color change according to the viewing angle.

And, when the light emitting position of the present invention is out of the maximum position, it is compared with the optimal position as follows. When the optimal position of the present invention is set, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of the light emitted from the organic light emitting diode. In addition, it can be seen that, when out of the maximum position, the color viewing angle Δu'v' at a viewing angle of 60° of the light emitted from the organic light emitting diode is 0.050. Accordingly, when the color viewing angle Δu'v' is greater than or equal to 0.050 when it deviates from the minimum position, a color change rate or color viewing angle defect according to an angle on the screen of the organic light emitting display device occurs. Accordingly, the consumer can sense the color change according to the viewing angle.

Therefore, it can be seen that the color viewing angle (Δu'v') is 0.016 at a viewing angle of 60° of light emitted from the organic light emitting device of the present invention when it is set to the optimal position of the present invention rather than when it is set to the minimum or maximum position of the embodiment. there is. In this embodiment, since the color viewing angle Δu'v' according to the viewing angle is small, it is possible to improve the color change rate felt by the consumer according to the viewing angle. In addition, since the color viewing angle Δu'v' of white is reduced, when implemented as an organic light emitting display device, it may be advantageous to realize the same color regardless of the viewing angle position. In addition, it is possible to improve the color change rate or color viewing angle defect according to the angle of the screen of the organic light emitting display device.

In addition, light emission positions of the first light emitting layer, the second light emitting layer, and the third light emitting layer may be set to improve luminous efficiency and color viewing angle in consideration of the spectral change rate and cavity peak of the light emitting layers.

The position of the second electrode may be in a range of 500 nm to 600 nm from the first electrode.

An emission position of the first emission layer may be in a range of 100 nm to 150 nm from the first electrode.

An emission position of the second emission layer may be in a range of 240 nm to 280 nm from the first electrode.

An emission position of the third emission layer may be in a range of 370 nm to 410 nm from the first electrode.

A color viewing angle (Δu'v') at a viewing angle of 60° of light emitted from the organic light emitting diode may be 0.016 or less.

17 is a cross-sectional view of an organic light emitting diode display including an organic light emitting diode according to an embodiment of the present invention, showing the organic light emitting diode according to the first, second, and third embodiments of the present invention. it will be used

As shown in FIG. 17 , the organic light emitting diode display 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 .

Although the thin film transistor TFT has an inverted staggered structure in FIG. 17 , it 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 selected from the group consisting of molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), nickel (Ni), neodymium (Nd), and copper (Cu). It may be a 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 layer (SiOx), a silicon nitride layer (SiNx), or a multilayer thereof, but is not limited thereto.

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

The source electrode 1133 and the drain electrode 1135 may be formed on the semiconductor layer 1131 . The source electrode 1133 and the drain electrode 1135 may be formed of a single layer or multiple layers, and may include molybdenum (Mo), aluminum (Al), chromium (Cr), gold (Au), titanium (Ti), and 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 1140 is formed on the source electrode 1133 and the drain electrode 1135 , and may be formed of a silicon oxide film (SiOx), a silicon nitride film (SiNx), or a multilayer thereof. Alternatively, it may be formed of an acryl 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 although only one sub-pixel is shown in the drawing, the color filter 1145 is disposed in the red sub-pixel, blue sub-pixel, and green sub-pixel 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 is limited thereto. doesn't happen

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

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

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

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

Although not shown in FIG. 17 , an encapsulation unit 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 unit may include a plurality of layers in which different inorganic materials are stacked, or a plurality of layers in which inorganic materials and organic materials are alternately stacked. And, an encapsulation substrate may be additionally configured on the encapsulation unit. 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 unit by an adhesive.

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 may be made within the scope without departing from the technical spirit of the present invention. . Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical spirit of the present invention, but to explain, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The protection scope of the present invention should be 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: white organic light emitting device
101, 201, 301: substrate
102, 202, 302: first electrode
104, 204, 304: second electrode
110, 210, 310: first light emitting unit
120, 220, 320: second light emitting unit
130, 230, 240: third light emitting unit
140, 240, 340: first charge generation layer
150, 250, 350: second charge generation layer
112, 212, 312: first hole transport layer
122, 222, 322: second hole transport layer
132, 232, 332: third hole transport layer
116, 216, 316: first electron transport layer
126, 226, 326: second electron transport layer
136, 236, 336: third electron transport layer
114, 214, 314: first light emitting layer
124, 224, 324: second light emitting layer
134, 234, 334: third light emitting layer

Claims (27)

a first light emitting part including a first light emitting layer and interposed 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, and includes a third light emitting unit on the second light emitting unit, wherein at least two light emitting layers of the first light emitting layer, the second light emitting layer and the third light emitting layer emit the same color to improve luminous efficiency. and the light emitting layers emitting the same color are disposed adjacent to each other,
The position of the first electrode is in the range of 500 nm to 600 nm from the second electrode,
The light emitting position of the third light emitting layer is in the range of 20 nm to 80 nm from the second electrode,
The light emission position of the second light emitting layer is in the range of 150 nm to 200 nm from the second electrode,
The light emission position of the first light emitting layer is a white organic light emitting device, characterized in that in the range of 270 nm to 330 nm from the second electrode. The method of claim 1,
The at least two light emitting layers are the first light emitting layer and the second light emitting layer. 3. The method of claim 2,
The first light emitting layer and the second light emitting layer is a white organic light emitting device, characterized in that one of a blue light emitting layer, a deep blue light emitting layer, or a sky blue light emitting layer. 3. The method of claim 2,
A peak wavelength (λmax) of the first light emitting layer and the second light emitting layer is in a range of 440 nm to 480 nm. The method of claim 1,
The light-emitting layer emitting a color different from the same color is one of a yellow-green light-emitting layer, or a green light-emitting layer, or a red light-emitting layer and a green light-emitting layer, or a yellow light-emitting layer and a red light-emitting layer, or a yellow-green light-emitting layer and a red light-emitting layer, or a combination thereof A white organic light-emitting device, characterized in that. The method of claim 1,
A peak wavelength (λmax) of the third light emitting layer is a white organic light emitting diode, characterized in that in the range of 540 nm to 575 nm. The method of claim 1,
The at least two light emitting layers are configured to be closer to the first electrode than to the second electrode. The method of claim 1,
A white organic light-emitting device, characterized in that at a viewing angle of 60° of the light emitted from the organic light-emitting device, a color viewing angle (Δu'v') is 0.016 or less. delete delete delete delete a first light emitting part including a first light emitting layer and interposed 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, and includes a third light emitting unit on the second light emitting unit, and the first light emitting layer and the second light emitting layer in consideration of the cavity peaks of the first light emitting layer, the second light emitting layer, and the third light emitting layer. and at least two light emitting layers of the third light emitting layer are composed of light emitting layers that emit light of the same color,
The position of the second electrode is in the range of 500 nm to 600 nm from the first electrode,
The light emitting position of the first light emitting layer is in the range of 100 nm to 150 nm from the first electrode,
The light emission position of the second light emitting layer is in the range of 240 nm to 280 nm from the first electrode,
The light emission position of the third light emitting layer is a white organic light emitting device, characterized in that in the range of 370 nm to 410 nm from the first electrode. 14. The method of claim 13,
The light emitting layers emitting the same color are the first light emitting layer and the second light emitting layer, and the first light emitting layer and the second light emitting layer are disposed adjacent to each other. delete delete delete 14. The method of claim 13,
The white organic light emitting device, characterized in that the cavity peak of the light emitting layer emitting a color different from the same color by the light emitting layers emitting the same color and the cavity peak of the light emitting layers emitting the same color are located in the light emitting region. 19. The method of claim 18,
The peak wavelength (λmax) corresponding to the emission region of the emission layers emitting the same color is in the range of 440 nm to 480 nm, and the peak wavelength (λmax) corresponding to the emission region of the emission layer emitting a color different from the same color is A white organic light-emitting device, characterized in that in the range of 540 nm to 575 nm. 14. The method of claim 13,
The light emitting layers emitting the same color are formed closer to the first electrode than to the second electrode. delete delete delete delete delete 14. The method of claim 13,
A white organic light-emitting device, characterized in that at a viewing angle of 60° of the light emitted from the organic light-emitting device, a color viewing angle (Δu'v') is 0.016 or less. 14. The method of claim 1 or 13,
A first charge generating layer is further provided between the first light emitting part and the second light emitting part, and a second charge generating layer is further provided between the second light emitting part and the third light emitting part white organic light emitting device.

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