KR20150078396A - Organic light emitting diode display device - Google Patents

Abstract

The present invention is to disclose an organic light emitting diode display device. The organic light emitting diode display device of the present invention comprises: a substrate including a plurality of unit sub pixels which have a red sub pixel, a green sub pixel, and a blue sub pixel; an organic light emitting device to emit light by being formed on the substrate; and a capping layer formed on the organic light emitting device. The light emitted from the organic light emitting device includes an electroluminescence (EL) spectrum which is discharged by passing through a resonance structure by the red, green, and blue sub pixels and a unique photoluminescence (PL) spectrum. A wavelength value having the maximum intensity of the EL spectrum is formed to have a shorter wave than the wavelength value having the maximum intensity of the PL spectrum in one sub pixel among the red, green, and blue sub pixels. A wavelength value having maximum intensity of the EL spectrum has a longer wave than a wavelength value having the maximum intensity of the PL spectrum in at least one sub pixel between the two sub pixels except for the sub pixel having the shortest wave. Thus, the organic light emitting diode display device according to the present invention can form a color reproduction range more than or equal to 100% and secure a stable viewing angle by controlling the position of the wavelength value having the maximum intensity of the EL spectrum for the wavelength value having the maximum intensity of the PL spectrum.

Description

[0001] The present invention relates to an organic light emitting diode display device,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic light emitting display, and more particularly, to an organic light emitting display having improved color reproducibility and improved viewing angle and improved optical reliability.

In recent years, as the information age has come to a full-fledged information age, a display field for visually expressing electrical information signals has been rapidly developed. In response to this, various flat panel display devices having excellent performance of thinning, light weight, Flat Display Device) has been developed to replace CRT (Cathode Ray Tube).

Specific examples of such flat panel display devices include a liquid crystal display device (LCD), an organic light emitting display (OLED), an electrophoretic display (EPD) A plasma display panel (PDP), a field emission display (FED), an electroluminescence display (ELD), and an electro-wetting display (EWD) And the like. In general, a flat panel display panel, which realizes images, is an essential component. The flat panel display panel includes a pair of substrates bonded together with an intrinsic light emitting material or a polarizing material layer therebetween.

Since an organic light emitting diode (OLED) display device, which is one of such flat panel display devices, includes an organic light emitting element that is a self light emitting element, a separate light source used in a liquid crystal display It is lightweight and thin. In addition, it has superior viewing angle and contrast ratio compared with liquid crystal display devices, is advantageous in terms of power consumption, can be driven by DC low voltage, has a quick response speed, is resistant to external impacts due to its solid internal components, It has advantages.

The organic light emitting device is a device for emitting light by applying an electric field by depositing an organic light emitting layer formed of an organic material between a cathode made of ITO or the like and a cathode made of aluminum (Al) or the like on a glass substrate. When a voltage is applied between the anode and the cathode of the organic light emitting diode, holes are injected from the anode, electrons are injected from the cathode, and then excitons are generated in the light emitting layer through migration. The organic light emitting display may use light emitted when the generated excitons fall to a ground state.

At this time, the conventional organic light emitting display device has a structure in which a reflection plate is formed in a substrate including electrodes or transistors of red (R), green (G), and blue (B) A color image can be realized. Using the micro cavity effect, an EL (electroluminescence) spectrum is formed through the resonance structure for each of red (R), green (G) and blue (B) sub-pixels. At this time, the EL spectrum can emit red (R), green (G), and blue (B) light through a resonance structure by adjusting optical distances, reflectance, transmittance, refractive index, and the like for each sub-pixel.

In addition, the conventional organic electroluminescent display device may include a PL (photoluminescence) spectrum unique to the red, green, and blue sub-pixels in addition to the EL spectrum through the micro cavity effect . The light of each sub-pixel can be further amplified due to overlapping of the EL spectrum and the PL spectrum. As a result, the color purity can be improved and the luminous efficiency can be improved.

However, when the wavelength value having the maximum intensity of the EL spectrum is different from the wavelength value having the maximum intensity of the PL spectrum, the viewing angle may be a problem. In order to improve the viewing angle problem, when the EL spectrum and the PL spectrum overlap each other, the conventional organic electroluminescent display device has a structure in which the wavelength value having the maximum intensity of the EL spectrum is smaller than the wavelength value having the maximum intensity of the PL spectrum, Green (G), and blue (B) light may be formed in a relatively short wavelength band region or may be formed in a relatively long wavelength band region in both red (R), green (G), and blue (B) light. However, although such a configuration can solve the view angle problem, it is difficult to realize a high color reproduction rate.

FIG. 1 is a view showing the color coordinates of a conventional organic light emitting display device.

Referring to FIG. 1, it can be seen that the color reproduction rate can be increased by shifting the emission wavelength in different directions for each color in the color coordinate system. In particular, it can be seen that the red (R) and blue (B) emission wavelengths must shift in opposite directions. In the case of blue (B), the emission wavelength should be shifted by a short wavelength. In the case of red (R), the emission wavelength should be shifted by a long wavelength.

When the EL spectrum and the PL spectrum overlap each other, the PL spectrum can not shift the wavelength value into a spectrum unique to each of red (R), green (G) and blue (B) sub-pixels. Therefore, in order to shift the emission wavelength, the wavelength of the EL spectrum must be adjusted. However, in order to prevent the viewing angle problem, the wavelength value having the maximum intensity of the EL spectrum must be formed in a short wavelength or a long wavelength in all the sub-pixels in comparison with the wavelength value having the maximum intensity of the PL spectrum.

Therefore, it is difficult to realize a high color reproduction rate in order to improve the viewing angle, and there is a problem that the viewing angle is distorted to improve the color reproduction rate.

The present invention provides an organic electroluminescent display device capable of realizing a high color gamut of 100% or more by adjusting the position of the wavelength value having the maximum intensity of the EL spectrum with respect to the wavelength value having the maximum intensity of the PL spectrum .

It is another object of the present invention to provide an organic light emitting display capable of ensuring a stable viewing angle while realizing a high color reproducibility.

According to an aspect of the present invention, there is provided an organic light emitting display including: a substrate having a plurality of unit sub-pixels including a red sub-pixel, a green sub-pixel, and a blue sub-pixel; An organic light emitting device formed on the substrate and emitting light; And a capping layer formed on the organic light emitting device, wherein the light emitted from the organic light emitting device has an electroluminescence (EL) spectrum and an intrinsic PL (photoluminescence) spectrum through a resonance structure for each of red, green and blue sub- And a wavelength value having the maximum intensity of the EL spectrum in at least one of the red, green, and blue sub-pixels is formed to have a shorter wavelength than a wavelength value having the maximum intensity of the PL spectrum, and the sub- The wavelength value having the maximum intensity of the EL spectrum in at least one of the sub-pixels other than the two sub-pixels is formed to have a longer wavelength than the wavelength value having the maximum intensity of the PL spectrum.

The organic electroluminescence display device according to the present invention can adjust the position of the wavelength value having the maximum intensity of the EL spectrum with respect to the wavelength value having the maximum intensity of the PL spectrum, It is effective.

Further, the organic light emitting display device according to the present invention has a second effect of ensuring a stable viewing angle while realizing a high color reproduction ratio.

FIG. 1 is a view showing the color coordinates of a conventional organic light emitting display device.
2 is a view illustrating an organic light emitting display device according to the present invention.
FIGS. 3A and 3B are graphs showing experimental results of Comparative Example 1 of a conventional organic light emitting display.
4A and 4B are graphs showing the results of an experiment of Comparative Example 2 of a conventional organic light emitting display.
5A and 5B are graphs showing experimental results of the organic light emitting display according to the first embodiment of the present invention.
6A and 6B are graphs showing experimental results of an organic light emitting display according to a second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are provided by way of example so that those skilled in the art can fully understand the spirit of the present invention. Therefore, the present invention is not limited to the embodiments described below, but may be embodied in other forms. In the drawings, the size and thickness of the device may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

2 is a view illustrating an organic light emitting display device according to the present invention.

2, an organic light emitting display according to an exemplary embodiment of the present invention includes a plurality of unit sub-pixels including a red sub-pixel R, a green sub-pixel G, and a blue sub- 50, the organic light emitting device 100 is formed. A capping layer 140 is formed on the organic light emitting device 100.

The organic light emitting device 100 includes a first electrode 110, an organic light emitting layer 120, and a second electrode 130. Although not shown in the drawing, a bank pattern may be formed on the first electrode 110 to expose the first electrode 110 only in the light emitting region. That is, the emission region and the non-emission region of the unit sub-pixel may be defined through the bank pattern.

The first electrode 110 may be an anode. At this time, the first electrode 110 serves as a reflective electrode, and may further include a reflective layer. The reflective layer may be formed of a metal material having a high reflectance such as aluminum (Al). In addition, the first electrode 110 may be formed of a transparent conductive material such as ITO. However, the material is not limited to the above material, and a material that can serve as the first electrode 110 in the organic light emitting diode 100 is generally sufficient.

The organic light emitting layer 120 may be formed on the first electrode 110 exposed through the bank pattern. The organic light emitting layer 120 may include a hole injection layer 121, a hole transporting layer 122, an emitting material layer 124, and an electron transporting layer 125 . At this time, although not shown in the figure, an electron injection layer may be further formed on the electron transport layer 125.

If necessary, the organic light emitting layer 120 may further include an organic layer other than the layers. For example, it may further include an optical adjustment layer 123 for an optimized thickness for each sub-pixel. The optical adjustment layer 123 may be formed of the same material as the hole transport layer 122. The optical control layer 123 may be omitted for each sub-pixel or may have a different thickness.

That is, in the organic light emitting display according to the present invention, the thickness of the organic light emitting layer 120 is different in consideration of the emission wavelength for each of red (R), green (G) and blue (B) Can be adjusted. As a result, a color image due to a micro-cavity effect can be realized. The micro cavity effect can improve the color purity and improve the light emission efficiently by using the optical resonance effect. Using such a micro cavity effect, the light emitted from the organic light emitting diode 100 includes an electroluminescence (EL) spectrum in which red (R), green (G) and blue (B) . The EL spectrum is formed by resonating in a direction perpendicular to the surface of the organic light emitting layer 120.

The light emitted from the organic light emitting diode 100 of the organic electroluminescence display device according to the present invention differs in each of the red (R), green (G) and blue (B) ) ≪ / RTI > spectrum. That is, the PL spectrum is an intrinsic luminescence spectrum of light emitted from the light emitting layer. The organic light emitting layer 120 may emit light including a PL spectrum which is an intrinsic emission wavelength according to red (R), green (G), and blue (B) in addition to the EL spectrum due to the micro- That is, the light emitted from the organic light emitting diode 100 may be light that is amplified by overlapping the EL spectrum and the PL spectrum.

The EL spectrum can adjust the wavelength value by controlling the thickness of the organic light emitting layer 120. However, the PL spectrum has a wavelength value that can not be controlled by a unique value of the light emitting layer itself. For example, the EL spectrum can adjust the wavelength value by adjusting the thickness of the optical control layer 123 of the organic light emitting layer 120.

A second electrode 130 is formed on the organic light emitting layer 120. When the first electrode 110 is an anode, the second electrode 130 may be a cathode. The second electrode 130 may be formed as a translucent electrode to emit light toward the front surface.

The element substrate 50 includes a thin film transistor Tr that drives each sub-pixel formed on an insulating substrate 10 formed of a material such as glass or plastic. The thin film transistor Tr includes a gate electrode formed on an insulating substrate 10, a gate insulating film covering the gate electrode, a semiconductor layer overlapping the gate electrode with the gate insulating film interposed therebetween to form a channel, And may be composed of a source electrode and a drain electrode opposed to each other. A planarizing film 20 is formed on the thin film transistor Tr. The thin film transistor (Tr) drain electrode formed on the element substrate 50 is connected to the organic light emitting diode first electrode 110.

A capping layer 140 is formed on the organic light emitting device 100. The capping layer 140 may be formed of an organic material or an inorganic material on the second electrode 130 of the organic light emitting diode 100. At this time, the capping layer 140 may also serve as one optical control layer. The capping layer 140 may increase the reflectance at the interface between the capping layer and the exterior by controlling the refractive index difference with the external. This increased reflectivity allows the capping layer 140 to exhibit a micro-cavity effect at a particular wavelength. At this time, the capping layer 140 may have a different thickness for each sub-pixel.

The organic electroluminescent display device according to the present invention has a structure including both the EL spectrum and the PL spectrum as described above. The EL spectrum and the PL spectrum are overlapped to further improve the luminous efficiency. However, in the case of the conventional organic electroluminescent display device, the viewing angle or the color recall ratio has been problematic due to the relationship between the EL spectrum and the PL spectrum. Hereinafter, the color recall ratio is a result of examination through CIE 1931, and the color coordinate change amount is a result of examination through CIE 1976.

FIGS. 3A and 3B are graphs showing experimental results of Comparative Example 1 of a conventional organic light emitting display.

3A is a diagram showing the emission spectrum of Comparative Example 1. Fig. 3A shows a conventional organic electroluminescent display device in which wavelengths having maximum intensity in the red sub-pixel R, green sub-pixel G and blue sub-pixel B of the EL spectrum are formed in both short wavelengths Fig. At this time, the color coordinates CIE (x, y) are white (W) (0.299, 0.312), red (R) (0.660, 0.339), green (G) (0.245, 0.720) Respectively. It was also confirmed that the color reproducibility of Comparative Example 1 was 98.7%. That is, the color recall rate is less than 100% and the high color recall ratio is not achieved.

The problem of viewing angle distortion is that the light is greenish and redish. If the light is greenish or redish, it is a problem in itself because it is visually recognizable. When the light is bluish, it is not a problem if the amount of change in color coordinates (Δu'v '@ 60 degrees) is 0.025 or less, but it is also a problem if the amount of change is large.

3B is a graph showing the amount of change in color coordinates of Comparative Example 1. FIG. Referring to FIG. 3B, a denotes a starting point of white light and b denotes an end point. In other words, as a result of examining the problem of the viewing angle deviation of Comparative Example 1 through the amount of change of the color coordinates, it was found that the problem of greenish or redish did not occur but was bluish. At this time, the maximum value of the amount of change (? U'v '@ 60 degrees) of the color coordinate is bluish with a large change amount of 0.034, which indicates that blue coloring is a problem.

Therefore, when the wavelength value having the maximum intensity of the EL spectrum of the conventional organic light emitting display device is formed in a short wavelength in comparison with the wavelength value having the maximum intensity of the PL spectrum, the color reproduction rate is low. Also, it was confirmed that defects may occur in terms of viewing angle.

4A and 4B are graphs showing the results of an experiment of Comparative Example 2 of a conventional organic light emitting display.

4A is a diagram showing the emission spectrum of Comparative Example 2. Fig. 4A is a graph showing a relationship between a wavelength value of maximum intensity in a red sub-pixel R, a green sub-pixel G and a blue sub-pixel B of the EL spectrum of a conventional organic electroluminescent display device Fig. At this time, the color coordinates CIE (x, y) are white (W) (0.299, 0.312), red (R) (0.676, 0.324), green (G) (0.270, 0.690) and blue Respectively. Further, it was confirmed that the color reproduction rate was 96%. That is, the color recall rate is less than 100% and the high color recall ratio is not achieved.

4B is a graph showing the amount of change in color coordinates of Comparative Example 2. FIG. Referring to FIG. 4B, a denotes a starting point of white light and b denotes an end point. In other words, as a result of examining the problem of viewing angle deviation of Comparative Example 2 through the amount of change of the color coordinates, it was found that there was no problem of redish, but it was greenish. Also, it was confirmed that the maximum value of the color coordinate change amount (? U'v '@ 60 degrees) was 0.013, which was not a change amount that would cause bluishness. When the light is greenish, it can be recognized as a defect even in a slight greenishness because it is visually recognizable easily.

Therefore, when the wavelength value having the maximum intensity of the EL spectrum of the conventional organic light emitting display device is formed in all long wavelengths as compared with the PL spectrum, the color reproduction rate is low. Also, it was confirmed that defects may occur in terms of viewing angle.

That is, in the conventional organic light emitting display, it is necessary to improve the color reproduction rate to less than 100%. Even if the wavelength value having the maximum intensity of the EL spectrum is formed in both the long wavelength and the short wavelength in comparison with the wavelength value having the maximum intensity of the PL spectrum A problem may arise in the viewing angle.

The organic electroluminescence display device according to the present invention has the maximum intensity of the EL spectrum in at least one of the red sub-pixel R, the green sub-pixel G and the blue sub-pixel B in order to improve the color reproducibility Is formed so as to have a short wavelength in comparison with the wavelength value having the maximum intensity of the PL spectrum. In addition, in at least one of the two sub-pixels, the wavelength value having the maximum intensity of the EL spectrum is formed to have a longer wavelength as compared with the wavelength value having the maximum intensity of the PL spectrum.

The difference between the wavelength values of the EL spectrum and the PL spectrum can be obtained by adjusting the wavelength value of the EL spectrum. Although the EL spectrum can adjust the wavelength value, the PL spectrum has a wavelength value that can not be adjusted to a unique value. Accordingly, it is possible to adjust the wavelength value having the maximum intensity of the EL spectrum so as to be formed in a long wavelength or a short wavelength by comparing it with a wavelength value having the maximum intensity of the PL spectrum. At this time, the wavelength of the EL spectrum can be controlled by controlling the thickness of the organic light emitting layer 120. [ For example, the EL spectrum can adjust the wavelength value by adjusting the thickness of the optical control layer 123 of the organic light emitting layer 120. The optical adjustment layer 123 may have a different thickness or may be omitted for each sub-pixel. In addition, the optical adjustment layer 123 may be formed of the same material as the hole transport layer 122.

The organic electroluminescent display device according to the present invention is applicable to six embodiments. The EL spectrum has a short wavelength in the red sub-pixel R, a long wavelength in the green sub-pixel G and a short wavelength in the blue sub-pixel B as compared with the PL spectrum. The second embodiment having a short wavelength in the green sub-pixel G and the short wavelength in the blue sub-pixel B, the second embodiment having the long wavelength in the red sub-pixel R, There is a third embodiment having a short wavelength and a long wavelength in the blue sub-pixel (B).

In addition, the fourth embodiment in which the EL spectrum has a long wavelength in the red sub-pixel R, a long wavelength in the green sub-pixel G, and a short wavelength in the blue sub-pixel B as compared with the PL spectrum, The fifth embodiment having a long wavelength in the green sub-pixel G and the short wavelength in the red sub-pixel R and having the short wavelength in the red sub-pixel R and the long wavelength in the green sub-pixel G, ), And has a long wavelength in the blue sub-pixel (B). That is, the first to sixth embodiments can be summarized as shown in the following table.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Wavelength value with maximum intensity R EL <PL EL> PL EL> PL EL> PL EL <PL EL <PL G EL> PL EL <PL EL <PL EL> PL EL> PL EL <PL B EL <PL EL <PL EL> PL EL <PL EL> PL EL> PL

The EL spectrum has a longer wavelength in the red subpixel R and a shorter wavelength in the blue subpixel B compared with the PL spectrum and the longer wavelength or shorter wavelength in the green subpixel G, The second embodiment or the third embodiment may be preferable.

Further, in order to improve the viewing angle, the organic light emitting display according to the present invention needs to minimize the difference between the wavelength value having the maximum intensity of the EL spectrum and the wavelength value having the maximum intensity of the PL spectrum. So that the difference between the wavelength value of the EL spectrum and the wavelength value of the PL spectrum is formed to be 5 nm or less. For example, in the red sub-pixel R, the green sub-pixel G and the blue sub-pixel B, the difference between the wavelength of the EL spectrum and the wavelength of the PL spectrum is formed to be 5 nm or less.

As a result, the organic light emitting display according to the present invention may not have the problem of greenish or redish due to the viewing angle problem. Also, the amount of change in color coordinates (? U'v '@ 60 degrees), which is a reference for bluish determination, is set to 0.025 or less, so that it is possible to have a variation in a range in which the viewing angle does not matter.

5A and 5B are graphs showing experimental results of the organic light emitting display according to the first embodiment of the present invention.

6A and 6B are graphs showing experimental results of an organic light emitting display according to a second embodiment of the present invention.

This is to verify the effect of the present invention through comparison with the comparative example of the conventional organic electroluminescent display device, and shows experimental results of some embodiments of the organic electroluminescent display device according to the present invention. However, this is for the purpose of demonstrating the effect, and the embodiment of the present invention can be made in various forms and should not be construed as being limited to the above-mentioned embodiments.

FIG. 5A is a diagram showing the emission spectrum of Example 1. FIG. 5A is a graph showing an EL spectrum of an organic light emitting display according to an embodiment of the present invention in which an EL spectrum has a short wavelength in a red subpixel R and a long wavelength in a green subpixel G, Fig. 2 is a diagram showing an emission spectrum according to the first embodiment having a short wavelength. At this time, the chromaticity coordinates CIE (x, y) are white (W) (0.299, 0.313), red (R) (0.672, 0.328), green (G) (0.247, 0.718) Respectively. Further, it was confirmed that the color reproduction rate was 103.2%. That is, the color reproduction rate exceeds 100% and a high color reproduction rate can be realized.

5B is a diagram showing the amount of color coordinate change in the first embodiment. Referring to FIG. 5B, a denotes a starting point of white light and b denotes an end point. In other words, as a result of examining the problem of the viewing angle shift of Example 1 through the amount of change of the color coordinates, it can be confirmed that the problem that the light is greenish or redish does not occur. Further, as a result of examining the degree of bluish, it was confirmed that the maximum value of the color coordinate change amount (? U'v '@ 60 degrees) was 0.019, and the variation amount in the viewing angle did not matter.

FIG. 6A is a diagram showing the emission spectrum of Example 2. FIG. 6A shows the EL spectrum of the organic electroluminescence display device according to the present invention in comparison with the PL spectrum in that it has a long wavelength in the red subpixel R and a short wavelength in the green subpixel G, And shows the emission spectrum according to the second embodiment having a short wavelength. At this time, the chromaticity coordinates CIE (x, y) are white (W) (0.299, 0.313), red (R) (0.672, 0.328), green (G) (0.247, 0.718) Respectively. At this time, it was confirmed that the color reproduction rate was 107%. That is, the color reproduction rate exceeds 100% and a high color reproduction rate can be realized.

6B is a diagram showing the amount of color coordinate change in the second embodiment. Referring to FIG. 6B, a denotes a starting point of white light and b denotes an end point. In other words, as a result of examining the problem of the viewing angle deviation of Example 2 through the amount of change of the color coordinates, it can be confirmed that the problem that the light is greenish or redish does not occur. Further, as a result of examining the degree of bluish, it was confirmed that the maximum value of the color coordinate change amount (? U'v '@ 60 degrees) was 0.020, and the variation amount in the range in which the viewing angle does not matter.

That is, the organic light emitting display device according to the present invention can realize a high color reproduction rate with a color reproduction rate exceeding 100%, and the viewing angle is not a problem.

Accordingly, the organic electroluminescence display device according to the present invention can adjust the position of the wavelength value having the maximum intensity of the EL spectrum with respect to the wavelength value having the maximum intensity of the PL spectrum, thereby realizing a high color reproduction rate of 100% A viewing angle can be ensured.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the claims.

50: element substrate
100: Organic light emitting device
110: first electrode
120: organic light emitting layer
130: second electrode
140: capping layer

Claims (9)

A substrate having a plurality of unit sub-pixels including a red sub-pixel, a green sub-pixel, and a blue sub-pixel;
An organic light emitting element formed on the substrate and including a light emitting layer for emitting light; And
And a capping layer formed on the organic light emitting element,
The light emitted from the organic light emitting device includes an EL (electroluminescence) spectrum emitted through a resonance structure for each of red, green, and blue sub-pixels and a PL (photoluminescence) spectrum, which is an intrinsic emission spectrum of light emitted from the light emitting layer for each sub- and,
The wavelength value having the maximum intensity of the EL spectrum in at least one of the red, green and blue sub-pixels is formed to have a shorter wavelength than the wavelength value having the maximum intensity of the PL spectrum,
Wherein a wavelength value having a maximum intensity of an EL spectrum in at least one of two sub-pixels other than the sub-pixel having a short wavelength is formed to have a wavelength longer than a wavelength value having a maximum intensity of the PL spectrum. Emitting display device.
The method according to claim 1,
Wherein a difference between a wavelength value having the maximum intensity of the EL spectrum and a wavelength value having the maximum intensity of the PL spectrum is 5 nm or less.
3. The method of claim 2,
Wherein a difference between a wavelength value having the maximum intensity of the EL spectrum and a wavelength value having the maximum intensity of the PL spectrum is the red, green, and blue sub-pixels of 5 nm or less.
The method according to claim 1,
Wherein the light emitted from the organic light emitting diode has a color coordinate variation of 0.025 or less.
The method according to claim 1,
Wherein a wavelength value having the maximum intensity of the EL spectrum is adjusted by changing a thickness of the organic light emitting layer of the organic light emitting device.
6. The method of claim 5,
Wherein the thickness of the organic light emitting layer is changed by omitting the optical control layer or by adjusting the thickness of the optical control layer.
The method according to claim 6,
Wherein the optical control layer is formed of the same material as the hole transport layer of the organic light emitting layer.
The method according to claim 1,
The wavelength value having the maximum intensity of the EL spectrum has a long wavelength in the red sub-pixel, a short wavelength in the blue sub-pixel, and a long wavelength or short wavelength in the green sub-pixel in comparison with the wavelength value having the maximum intensity of the PL spectrum The organic electroluminescent display device comprising:
The method according to claim 1,
Wherein the EL spectrum is formed by resonating in a direction orthogonal to the surface of the light emitting layer.

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