KR100683658B1 - Organic electro luminescence display device - Google Patents

Abstract

According to the present invention, an organic light emitting display device includes a substrate, a first electrode layer formed on an upper surface of the substrate, and organic layers formed on an upper surface of the first electrode layer to implement a color image on the upper surface of each organic layer. And a light loss preventing color control layer having a second electrode layer formed, the light loss preventing color adjusting layer having at least two regions having different refractive indices between the layers having a high refractive index on the optical path emitted from the organic layer. The pitches of the regions having the same refractive index are different from each other in the regions corresponding to the organic layers emitting light of different colors.

Description

Organic electroluminescence display device

1 is a cross-sectional view showing a state in which light of a conventional organic light emitting display device is extracted;

2 is a perspective view of an organic light emitting display device according to the present invention;

3 is a cross-sectional view of the organic light emitting display device shown in FIG. 2;

4 to 6 are perspective views showing the light loss prevention color control layers

7 is a cross-sectional view showing another embodiment of an organic light emitting display device according to the present invention;

8 and 9 are cross-sectional views illustrating still another embodiment of an organic light emitting display device according to the present invention;

10 is a cross-sectional view illustrating a light extraction state of an organic light emitting display device according to the present invention;

11 is a graph showing an average intensity of a wavelength band.

The present invention relates to an organic electroluminescent display, and more particularly, to an organic electroluminescent display having an improved layer for improving emission color purity by adjusting a light emission spectrum on a path of light generated by an organic layer.

In general, an organic light emitting display device is a self-luminous display that electrically excites fluorescent organic compounds and emits light, and can be driven at low voltage, is easy to thin, and is pointed out as a problem in liquid crystal display devices such as wide viewing angle and fast response speed. It is attracting attention as the next generation display that can solve the shortcomings.

These organic electroluminescent displays were developed in stacks by Eastman Kodak and commercialized as green displays with improved lifetimes by Pioneer. On the other hand, the organic electroluminescent display device has been actively researched as a color displayer having various characteristics of molecular structure, which is an advantage of organic materials, and having excellent characteristics such as DC low voltage driving, thinness, and self-luminous property.

In the organic light emitting diode display, an organic layer having a predetermined pattern is formed on glass or other transparent insulating substrate, and electrode layers are formed on upper and lower portions of the organic layer. The organic film consists of organic compounds.

In the organic electroluminescent display device configured as described above, as the anode and cathode voltages are applied to the electrodes, holes injected from the electrode to which the anode voltage is applied are moved to the light emitting layer of the organic layer via the hole transport layer, and the electrons are The cathode voltage is injected into the light emitting layer via the electron transporting layer. In this light emitting layer, electrons and holes recombine to produce excitons, and as the excitons change from the excited state to the ground state, the fluorescent molecules in the light emitting layer emit light to form an image.

The light efficiency of the organic light emitting display device driven as described above is divided into internal efficiency, external efficiency, or light coupling efficiency, and the internal efficiency is photoelectric conversion of the organic light emitting material. Depending on the efficiency, the external efficiency is due to the refractive index of each layer constituting the organic light emitting display device. That is, when the light emitted by the organic film is emitted above the critical angle, reflection occurs at the interface between the substrate and the electrode layer or the organic film and the electrode layer, thereby preventing the light from being taken out.

On the other hand, in the conventional organic light emitting display device, as shown in FIG. 1, light emitted from the organic layer 10 is transmitted to the glass substrate 11, which is a transparent substrate at the interface of the electrode 12 made of ITO. The transmission efficiency is based on the following formula 1/2 (N _out / N _in ) ² . Where N is the refractive index.

 Based on the above formula, the light extraction rate for each color of the conventional organic light emitting display device is shown in the following table.

 Blue organic film   Red organic film Green organic film  Wavelength (nm)      450    620 530 Refractive index of the ITO electrode (n)      2.01    1.76 1.93 Refractive index of glass substrate (n)   1.525  1.515 1.52 Light extraction rate      29%     37%   34%

         As shown in the above table, it can be seen that due to the difference in refractive index between the ITO electrode and the glass substrate, a large amount of light is dissipated by 60% or more in the organic light emitting display.

An example of a conventional organic electroluminescent device for preventing such a decrease in light extraction rate is disclosed in Japanese Laid-Open Patent Publication No. 63-172691. The disclosed organic electroluminescent display includes a substrate having light condensation such as a protruding lens. However, such a convex lens for condensing is difficult to form on the substrate because the pixel according to the emission of the organic film is very small.

Japanese Laid-Open Patent Publication No. 62-172691 discloses an organic electroluminescent display with a first dielectric layer interposed between a transparent electrode layer and a light emitting layer and a second dielectric layer having a refractive index between the first dielectric layer and the transparent electrode on a transparent electrode side. An apparatus is disclosed.

Japanese Patent Application Laid-Open No. Hei 1-220394 discloses an organic electroluminescent display device in which a lower electrode, an insulating layer, a light emitting layer, and an upper electrode are formed on a substrate, and a mirror is formed to reflect light on one surface of the light emitting layer.

Since the organic light emitting display device has a very thin thickness of the light emitting layer, it is very difficult to install a mirror for reflection on the side surface, and as a result, the production cost increases.

Japanese Laid-Open Patent Publication No. 11-283751 discloses a configuration in which an organic electroluminescent display device having one or more organic layers between an anode and a cathode includes a diffraction grating or a zone plate as a component.

Such an organic light emitting display device has to form irregularities on the surface of the substrate or the fine electrode pattern layer or to provide a separate diffraction grating, so that the manufacturing process is difficult and productivity cannot be improved. In addition, when the organic layer is formed on the uneven surface, the surface roughness of the organic layer is increased due to the unevenness, so that the light emission efficiency can be further increased by changing the pattern of the light loss prevention layer in association with the durable light spectrum of the organic light emitting display device. And it turned out that brightness can be improved.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and an object thereof is to provide an organic light emitting display device which can reduce light loss inside to increase luminous efficiency and improve color reproducibility of light emitted from each organic film. There is this.

Another object of the present invention is to provide an organic light emitting display device which can reduce light loss by using a light dispersion effect at an interface between a high refractive index layer and a low refractive index layer.

Another object of the present invention is to provide an organic light emitting display device having a light loss prevention color filter effect, which replaces the role of a color control filter that takes and uses light loss.

In order to achieve the above object, the organic light emitting display device of the present invention

A substrate, a first electrode layer formed on an upper surface of the substrate, organic films formed on an upper surface of the first electrode layer, and a second electrode layer formed on an upper surface of each organic layer to implement a color image,

And a light loss preventing color adjusting layer having at least two regions having different refractive indices between the layers having a high refractive index on the optical path emitted from the organic layer, wherein the light loss preventing color adjusting layer has a pitch of the regions having the same refractive index. It is characterized in that different in the region corresponding to each of the organic layers that emit light of different colors.

In the present invention, the pitch of the areas of the same refractive index of the light loss prevention color control layer is equal to the following inequality (mean emission refractive index / average refractive index of the light loss prevention color control layer) + 100nm < It satisfies the pitch <(average refractive index of the light emission wavelength / light loss prevention color adjustment layer)-100 nm of the same area | region. Preferably, the pitches of the regions having the same refractive index are 150 nm to 900 nm, and the pitches of the divided regions having different refractive indices are preferably less than twice the wavelength of the visible light region. In the above relation, the upper and lower limits of 100 nm are for controlling the emission spectrum of the emission wavelength of the red, green, and blue phosphors, and the wavelength spectrum of the emission spectrum thereof is substantially 50 to 100 nm.

Preferably, the light loss preventing color control layer is formed between the substrate and the first electrode. When the organic light emitting display device is a top emission type, the first electrode is made of metal, and the second electrode layer is formed of ITO. It is preferable to form the light loss prevention color control layer on the upper surface thereof.

On the other hand, the light loss prevention color control layer is formed of inorganic materials having different refractive indices, the refractive index difference △ n of the inorganic materials is preferably at least 0.3, the inorganic material is SiOx (x> 1), SiNx, Si ₃ N ₄ , TiO ₂ , MgO, ZnO, Al ₂ O _3, SnO _2, In ₂ O _3, MgF ₂ CaF _{2 It} is one selected from the group consisting of.

Another aspect of the organic electroluminescent display device for achieving the above object is

A transparent substrate;

A transparent first electrode layer formed in a predetermined pattern on a substrate, organic layers formed on an upper surface of each first electrode layer, an insulating layer formed on an upper surface of the substrate to expose the organic layers, and a predetermined pattern on an upper surface of the organic layer and the insulating layer A pixel region including a second electrode layer formed of the first electrode layer;

A driving region formed on the transparent substrate and including thin film transistors for switching transparent electrodes;

And a light loss preventing color control layer having at least two regions having different refractive indices between the layers having a high refractive index on the optical path emitted from the organic layer, wherein the pitches of the regions having the same refractive index of the light loss preventing color adjusting layer It is characterized in that different in the region corresponding to each of the organic layers that emit light of different colors.

In the present invention, the pitch of the areas of the same refractive index of the light loss prevention color control layer is equal to the following inequality (mean emission index / average refractive index of the light loss prevention color control layer) + 100nm <pitch of the areas of the same refractive index <(light emission Average refractive index of the wavelength / light loss prevention color control layer)-100 nm.

Another aspect of the organic light emitting display device for achieving the above object is

 Transparent substrate,

A buffer layer formed on the substrate, a thin film transistor layer formed on the buffer layer, an insulating layer filling the thin film transistor layer, and a first electrode layer formed in a predetermined pattern on the upper surface of the insulating layer and selectively applied by a thin film transistor. And a planarization film having an opening formed to expose the first electrode layer, an organic film formed on an upper surface of the first electrode layer, and a second electrode layer formed in a predetermined pattern on an upper surface of the organic film and the insulating layer,

A light loss preventing color control layer having at least two regions having different refractive indices between the first electrode layer and the planarization layer or between the layers having the high refractive indexes on the optical path emitted from the organic layer on one side of the upper surface of the second electrode layer; And pitches of regions having the same refractive index of the light loss preventing color control layer having different configurations in regions corresponding to the organic layers emitting light of different colors.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

An example of a PM type organic electroluminescent display (PMOLED (Passive matrix organic light emitting display)) according to the present invention is shown in FIGS.

Referring to the drawings, the organic light emitting display device includes a transparent first electrode layer 61 formed in a predetermined pattern on an upper surface of the transparent substrate 50 and an organic layer formed by being stacked on the upper surface of the first electrode layer 61. 70 and the second electrode layer 62 formed in a predetermined pattern on the upper surface of the organic layer 70 and the light extraction path emitted from the organic layer 70. Are included in the region and the pitch of the region having the same refractive index in the region corresponding to each organic film 70 for realizing a color image includes a different light loss preventing color control layer (80). The cap plate 63 is provided as a sealing means provided on the substrate 50 to surround the first electrode layer 61, the organic layer 70, and the second electrode layer 62.

The first electrode layer 61 is an anode formed on the upper surface of the transparent substrate 50 and is made of transparent conductive material ITO, and as shown in FIG. 2, the electrode line 61a on the stripe is installed in parallel with each other. )

As shown in FIG. 3, the organic layer 70 is formed by patterning first, second, and third organic layers 71-73 that emit red, green, and blue light to implement a color image. Each of the first, second, and third organic films 71-73 is sequentially stacked from the top surface of the first electrode layer 61 as shown in FIG. 4, the hole injection layer 70a, the hole transport layer 70b, and the emission layer. 70c, the electron injection layer 70d. The first, second and third organic films 71-73 are organic compounds, such as 8-hydroxyquinolino-aluminum (Alq ₃ ), low molecular weight or poly (p-phenylenevinylene), poly (2-methoxy -5- (2'-ethylhexyloxy) -1,4-phenylenevinylene) and the like, but is not limited thereto and may vary depending on the color.

The second electrode layer 62 is made of a conductive metal and may be formed of a plurality of stripe electrode lines 62a formed in a direction orthogonal to the first electrode layer 61.

The light loss preventing color adjusting layer 80 is disposed between components of the organic light emitting display, that is, the layers having the high refractive index among the substrate, the first electrode, the organic layers, and the second electrode layer. As described above, it is provided between the substrate 50 having a large light loss and the first electrode layer 61 made of ITO. The light loss prevention color control layer 80 may be installed between layers having a large difference in refractive index as described above. When the second electrode layer is made of a transparent material and light is emitted to the front surface, the light loss prevention color control layer 80 may be disposed on an upper surface of the second electrode layer. An optical loss preventing color adjusting layer may be formed.

  As shown in FIGS. 3 to 6, the light loss preventing color adjusting layer 80 is a substrate 50 in a region corresponding to each of the first, second and third organic layers 71-73 for implementing a color image. ), The first region 81 and the second region 82 having different refractive indices coexist on. The light loss prevention color control layer 80 may be formed on the entire surface of the substrate. The first region 81 of the light loss preventing color adjusting layer 80 is arranged in a dot shape with respect to the second region 82, and the shape thereof is not limited to the dot type. In this case, the material constituting the first region 81 is preferably such that the difference Δn of the refractive indexes of the material constituting the second region 82 is 0.3 or more and 3 or less, but the value of the refractive index difference Δn is as large as possible. This is preferable. In addition, the thickness T1 of the light loss preventing color control layer 80 is preferably two times or less of the visible light wavelength, more preferably 0.03 to 50 μm. As shown in FIG. 5, the first region 81 constituting the light loss preventing color control layer 80 is formed to have the same depth d1 as the thickness T1 of the light loss preventing color control layer in the thickness direction. As shown in FIG. 6, the light loss preventing color adjustment layer 80 may be formed to a depth d2 not deeper than the thickness T1.

 Meanwhile, pitches of the first regions 81 of the light loss preventing color control layer in regions corresponding to the first, second, and third organic layers 71, 72, and 73 for implementing the color image are Each of P1, P2, and P3 is formed differently. The pitches of the first regions of the light loss preventing color control layer formed in the regions corresponding to the first, second, and third organic layers 71, 72, and 73 may be the first, second, and third organic layers 71-. 73, it is preferable to set so as to change the distribution of the spectrum by considering the wavelength according to the color of the light emitted from. Each of the pitches P1, P2, and P3 of the first region 81 provided in the region corresponding to the first, second, and third organic layers 71-73 is the first, second, and third organic layers 71-73. It is preferable to set the wavelength of the light emitted from the range of ± 100 nm of the value obtained by dividing the average refractive index of the light loss preventing color adjusting layer. This can be expressed as an inequality (average refractive index of the wavelength / light loss prevention layer) + 100 nm <pitch P1 to P3 of the first region <(average refractive index of the wavelength / overloss prevention layer)-100 nm. The pitches P1, P2, and P3 of the first region are preferably formed within a range of 150 nm to 900 nm.

 In addition, the light loss prevention color control layer 80 is preferably such that the light transmittance is 80% or more so as to reduce the loss of light generated from the first, second and third organic layers 70.

On the other hand, the material of the light loss prevention color control layer 80 may be made of inorganic materials or polymers. When the light loss prevention color control layer 80 is made of an inorganic material, SiOx (x> 1), SiNx, Si ₃ N ₄ TiO ₂ , MgO, ZnO, Al ₂ O _3, SnO _2, In ₂ O _3, MgF ₂ It may consist of one phase inorganic material selected from the group consisting of CaF ₂ . For example, the coating film may be formed by using SiO x (x> 1) having a refractive index of 1.6 and doped with TiO having a refractive index of 2.5 to 3.

The light loss prevention color control layer 80 may be formed by removing the photosensitive agent from the result of coating and exposure treatment of the composition including the photosensitive material and the binder resin. At this time, the photosensitive material is made of one of the halogen compounds, the bonding resin may be made of gelatin.

FIG. 7 illustrates an example of an AM type organic electroluminescent display (AMOLCD) as an organic electroluminescent display according to the present invention.

Referring to the drawings, a buffer layer 91 is formed on a transparent substrate 90, a pixel region 200 having a pixel and a transparent electrode 92 for forming the pixel region 200, and a thin film transistor, respectively, on the buffer layer 91. And a driving region 300 in which a TFT and a capacitor are formed.

In the driving region, a p-type or n-type semiconductor layer 92 arranged in a predetermined pattern on the upper surface of the buffer layer 91 is buried by the gate insulating layer 93, and on the upper surface of the gate insulating layer 93. The gate electrode layer 94 corresponding to the semiconductor layer 92, the first insulating layer 95 filling the same, and the contact holes 96a and 97a formed in the first insulating layer 95 and the gate insulating layer 93. A thin film transistor comprising a drain electrode 96 and a source electrode 97 formed on the first insulating layer 95 and connected to both sides of the semiconductor layer 92, respectively, and connected to the source electrode 97. A capacitor 110 including a first auxiliary electrode 111 formed on an upper surface of the first insulating layer 95 and a second auxiliary electrode 112 facing the first electrode and embedded in the first insulating layer 95. It includes.

A second insulating layer 98 formed on the upper surface of the first insulating layer 95 and a planarization film 99 having openings 99a formed in the pixel formation region are formed. A first electrode layer 100 electrically connected to the drain electrode 96 is formed on a bottom surface of the opening of the planarization layer 99, and an organic layer 70 is stacked on the first electrode layer 100. The second electrode layer 101 is formed on the organic layer and the planarization film 99.

Meanwhile, in the organic light emitting display device as described above, the first electrode layer 100 is made of ITO, which is a transparent conductive material, and the substrate 51, the buffer layer 91, the gate insulating layer 93, and the first electrode. In the case of the bottom emission type in which the second insulating layers 95 and 98 are made of a transparent material, first and second refractive indexes are different in a predetermined pattern between the transparent electrode 100 and the second insulating layer 98. A light loss prevention color control layer 80 in which the areas 81 and 82 coexist is provided. The light loss prevention color control layer 80 has the same configuration as the above-described embodiment. That is, as in the PM type organic electroluminescent device, the pitches of the first regions of the light loss preventing color control layers formed in the regions corresponding to the organic layers 71 to 73 constituting the color image are different from each other. Since the configuration of the light loss leaving color adjusting layer is the same as the above-described embodiment, it will not be described again.

    On the other hand, the installation position of the light loss prevention color control layer 80 is not limited by the above embodiment, it can be provided between the layers having a large refractive index difference Δn. For example, as shown in FIGS. 8 and 9, the substrate 51 may be disposed between the substrate 51 and the buffer layer 91.

The operation of the organic light emitting display device configured as described above is as follows.

2 and 3, a predetermined voltage is applied to the selected electrodes of the first electrode layer 61 and the second electrode layer 62 or the thin film transistor is selected as shown in FIG. 7. When a predetermined voltage is applied to the first electrode 100 and a voltage is applied to the second electrode 111, holes injected from the first electrode layer 61, which is an anode, pass through the hole transport layer 70a to emit light. Moved to 70c, electrons are injected from the second electrode layer 82 to the light emitting layer 70c via the electron transport layer 70d. Electrons and holes recombine in the light emitting layer 73 to generate excitons, and as the excitons change from the excited state to the ground state, the fluorescent molecules of the light emitting layer 70c emit light. The light generated at this time is the transparent first electrode layer 61, the light loss prevention color control layer 80 and the substrate 50, or as shown in Figure 7, the first electrode layer 61 and the first and second insulating layers, Extracted to the outside through the buffer layer and the substrate, the light between the first electrode layer 61 and the substrate 50 made of ITO having a large difference in refractive index, or between the first electrode layer 100 and the second insulating layer 98 Since the loss preventing color adjusting layer 80 is formed, the reflection of light at the interface can be prevented from being lost.

 That is, since the refractive index of the organic layer 71-73 or the first electrode layer including the light emitting layer is higher than the refractive index of the glass or the second insulating layer constituting the substrate 50, it is reflected at the interface of the substrate 50. However, since there is a light loss preventing color adjusting layer 80 having first and second regions having different refractive indices therebetween, the light having a component parallel to the light loss preventing color adjusting layer 80 of the incident light is shown in FIG. As described above, when it coincides with a pseudo bandgap of the pitch of the first region of the light loss preventing color adjusting layer 80, the light loss prevention color adjusting layer 80 does not proceed in the horizontal direction but is emitted to the front surface. Therefore, the first, second and third organic films 71-73 adjust the pitch P1, P2, P3 of the first region of the light loss preventing color adjusting layer 80 according to the wavelength of the light emitted from the first. The intensity of each wavelength of the light emitted from the 2,3 organic film 71-73 can be adjusted, and further, the first, 2, 3 organic film can be improved without improving the first, 2, 3 organic film 71-73. The color coordinates of the light extracted from the films 71-73 can be adjusted.

The inventors of the present invention can clearly see the change in the luminescence properties according to the pitch change of the first region constituting the light loss prevention color control layer through the following experiment.

{Experiment 1}

In the present invention, a test organic electroluminescent display device having a light loss preventing color control layer positioned between a substrate and a first electrode layer is fabricated using SiO 2 as a low refractive material and ITO as a high refractive material. In constructing the light loss preventing color control layer, the pitch of the region having the low refractive index, that is, the first region, is 270 nm, and the depth of the first region is 30 nm.

It can be seen that the emission spectrum obtained from the organic light emitting display device configured as described above is biased toward the short wavelength side as shown in FIG. 11, and when the pitch decreases, the emission spectrum shifts to the blue side. It was found that the efficiency of the organic light emitting display device was 2.761 m / W, and the color coordinates were x = 0.2701 and y = 0.650.

{Experiment 2}

In the present invention, the pitch of the first region of the light loss prevention color control layer is maintained at 320 nm under the same conditions as the above embodiment. In this case, the efficiency of the organic light emitting display device was 5.501 m / W, and the color coordinates were x = 0.3222 and y = 0.6353.

{Experiment 3}

 In the present invention, the pitch of the first region of the light loss preventing color control layer is maintained at 370 nm under the same conditions as the above embodiment. In this case, the efficiency of the organic light emitting display device was 3.211 m / W, and the color coordinates were x = 0.3703 and y = 0.5723. As shown in FIG. 11, it was found that the spectrum of the long wavelength region became stronger as the pitch of the first region became longer.

{Comparative Example}

In the present invention, an organic light emitting display device is fabricated in which a light loss preventing color control layer is not formed between the substrate and the first electrode layer. It can be seen that the spectrum of the organic electroluminescent display is driven over a wide wavelength band as shown in FIG. 4. In this organic electroluminescent display, the efficiency was found to be 2.11 m / W, and the color coordinates were x = 0.2995 and y = 0.6395.

It can be seen that the emission spectrum obtained from the organic light emitting display device configured as described above is shifted toward the short wavelength side as shown in FIG. 11, and when the pitch decreases, the shift spectrum shifts to the blue side. It was found that the efficiency of the organic light emitting display device was 2.761 m / W, and the color coordinates were x = 0.2701 and y = 0.650.

The following table was obtained by summarizing the results of the first, second and third experiments and the comparative example.

  A (mA / ㎠)   LUMINANCE     Cd / A     1m / W          Color coordinates      x      y     Comparative example 0.5474208 14.62 2.6707058 2.0975674 0.2995 0.6395 270 nm 2.6199583 92.04 3.513033 2.7591296 0.2702 0.6501 320 m 1.4500417 101.6 7.0066952 5.5030455 0.3222 0.6353   370 nm 1.841125 75.35 4.0926064 3.2143256 0.3703 0.5723220

As can be seen from the table and the embodiment, it can be seen that the emission spectra of the first, second and third organic layers are enhanced in accordance with the pitch of the first region. In FIG. 10, since the x and y components of the light incident on the light loss prevention layer are restricted in the x and y directions according to the pitch of the first area of the light loss prevention color control layer, the period of the first area is 1, 2, Since the distribution of the spectrum is changed without improving the material of the three organic films, the light emission characteristics and the color purity of the first, second and third organic films for implementing color images can be improved by using the same.

Since the color purity can be adjusted in the visible light region, it is actually (380 / average refractive index of the color loss prevention layer) <pitch of the first region (P1 ~ P3) <(780 / light loss prevention color adjustment Average refractive index of the layer). .

(Emission wavelength / light loss prevention color control layer) + 100 nm <pitch of the first region (P1 ~ P3) <(Emission wavelength / (and) light loss prevention color control layer)-100nm to be displayed Can be. The upper and lower limit of the inequality equation is set to the upper and lower limits of the RGB region and each control region because the width of the general spectrum of the RGB emission spectrum to be adjusted is around 100 nm. The inequality light loss preventing color control layer acts as a kind of two-dimensional diffraction, so that the emission spectrum and the period causing diffraction, that is, the period of the pitch region, are two-dimensional planes at a period value obtained by converting the emission spectrum into the refractive index of the medium. Diffraction of light traveling in the direction of the front direction has the effect of increasing the color. Therefore, the pitch period of the light loss preventing color adjustment layer can select only the portion to be increased in the emission spectrum.

The organic electroluminescent device of the present invention made as described above can reduce the internal loss of light and further increase the light extraction efficiency by adjusting the pitch of the first and second regions formed of a material having at least two refractive indices. It is possible to adjust the light spectrum and color coordinates emitted from the 2,3 organic film.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary and one of ordinary skill in the art will understand that various modifications and variations are possible. Therefore, the present invention will be defined by the technical spirit of the appended claims the true technical protection scope of the present invention.

Claims (19)

A substrate, a first electrode layer formed on an upper surface of the substrate, organic films formed on an upper surface of the first electrode layer to implement a color image, and a second electrode layer formed on an upper surface of each organic film, And a light loss preventing color adjusting layer having at least two regions having different refractive indices between layers having a high refractive index on the light path emitted from the organic layer, wherein pitches of regions having the same refractive index of the light loss preventing color adjusting layer An organic electroluminescent display device which is different in a region corresponding to each of the organic layers emitting light of different colors. The method of claim 1, The pitch of the areas of the same refractive index of the light loss prevention color control layer is equal to the following inequality (average refractive index of the wavelength / light loss prevention layer) + 100nm <the pitch of the areas of the same refractive index <(average of the wavelength / light loss prevention color control layer Refractive index)-100 nm.   The method of claim 2, An organic light emitting display device, wherein the pitch of the regions having the same refractive index is 150 nm to 900 nm. The method of claim 1, The pitch of the divided regions having different refractive indices has a thickness less than twice the wavelength of the visible light region. The method of claim 1, The formation depth of the divided regions having different refractive indices is not deeper than the thickness of the light loss preventing color control layer. The organic light emitting display device of claim 1, wherein the light loss preventing color control layer is formed between the substrate and the first electrode layer. The method according to any one of claims 1 to 6, The light loss prevention color control layer is formed of inorganic materials having different refractive indices, and the refractive index difference of the inorganic materials is preferably 0.3 or more, and the inorganic material is SiOx (x> 1), SiNx, Si ₃ N ₄ , TiO ₂ And MgO, ZnO, Al ₂ O _3, SnO _2, In ₂ O _{3, and} MgF ₂ CaF ₂ . A transparent substrate; A transparent first electrode layer formed in a predetermined pattern on a substrate, organic layers formed on an upper surface of each first electrode layer, an insulating layer formed on an upper surface of the substrate to expose the organic layers, and a predetermined pattern on an upper surface of the organic layer and the insulating layer A pixel region including a second electrode layer formed of the first electrode layer; A driving region formed on the transparent substrate and including thin film transistors for switching transparent electrodes; And a light loss preventing color control layer having at least two regions having different refractive indices between the layers having a high refractive index on the optical path emitted from the organic layer, wherein the pitches of the regions having the same refractive index of the light loss preventing color adjusting layer The organic light emitting display device of claim 1, wherein the organic light emitting display device is different in a region corresponding to each of the organic layers emitting light of different colors. The method of claim 8, The pitch of the areas having the same refractive index of the light loss preventing color control layer is equal to the following inequality (average refractive index of the wavelength / light loss preventing layer) + 100 nm <the pitch of the area having the same refractive index <(average refractive index of the wavelength / overloss preventing layer)- An organic electroluminescent display characterized by satisfying 100 nm. The method of claim 9, An organic light emitting display device, wherein the pitch of the regions having the same refractive index is 150 nm to 900 nm. The method of claim 8, The pitch of the divided regions having different refractive indices has a thickness less than twice the wavelength of the visible light region. The method of claim 8, The formation depth of the divided regions having different refractive indices is not deeper than the thickness of the light loss preventing color control layer. The organic light emitting display device of claim 8, wherein the light loss preventing color control layer is formed between the substrate and the first electrode layer. Transparent substrate, A buffer layer formed on the substrate, a thin film transistor layer formed on the buffer layer, an insulating layer filling the thin film transistor layer, and a first electrode layer formed in a predetermined pattern on the upper surface of the insulating layer and selectively applied by a thin film transistor. And a planarization film having an opening formed to expose the first electrode layer, an organic film formed on an upper surface of the first electrode layer, and a second electrode layer formed in a predetermined pattern on an upper surface of the organic film and the insulating layer, A light loss preventing color control layer having at least two regions having different refractive indices between the first electrode layer and the planarization layer or between the layers having the high refractive indexes on the optical path emitted from the organic layer on one side of the upper surface of the second electrode layer; And a different configuration in a region corresponding to each of the organic layers that emit light of different colors with the same refractive index of the light loss preventing color control layer. The method of claim 14, The pitch of the areas having the same refractive index of the light loss preventing color control layer is equal to the following inequality (average refractive index of the wavelength / light loss preventing layer) + 100 nm <the pitch of the area having the same refractive index <(average refractive index of the wavelength / overloss preventing layer)- An organic electroluminescent display characterized by satisfying 100 nm. The method of claim 15, An organic light emitting display device, wherein the pitch of the regions having the same refractive index is 150 nm to 900 nm. The method of claim 15, The pitch of the divided regions having different refractive indices has a thickness less than twice the wavelength of the visible light region. The method of claim 14, The formation depth of the divided regions having different refractive indices is not deeper than the thickness of the light loss preventing color control layer. The organic light emitting display device of claim 14, wherein the light loss preventing color control layer is formed between the substrate and the first electrode layer.

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