JP2005317208A - Organic electroluminescent display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent display device having an element structure that is effective in the improvement of emission luminance or emission efficiency. <P>SOLUTION: In the organic electroluminescent display device, an anode electrode layer 2 that is substantially transparent to electroluminescent light and an organic electroluminescence layer 8 are successively laminated onto a transparent substrate 1, a cathode electrode layer 7 is superposed thereon, and a DC voltage is applied between the anode and cathode electrode layers 2 and 7 and a DC current is injected to the electroluminescence layer. The layer is excited to emit light and to take it out of a surface at a side opposite to the surface on which the electroluminescence layer is formed on the transparent substrate. In such an organic electroluminescent display device, a light interference layer 11 made of a dielectric material that is transparent to the electroluminescence light is inserted between the transparent substrate 1 and the anode electrode layer 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an organic electroluminescence display device, and more particularly to a transparent conductive film substrate used therefor.

  In recent years, the demand for flat panel display (FPD), which is advantageous for light weight, low power consumption, and large area as a display device replacing a cathode ray tube (CRT), has rapidly expanded. Yes. Typical FPDs include a liquid crystal display (LCD), a plasma display panel (PDP), an organic electroluminescence (organic EL) display (OLED), a field emission display (FED), etc. In particular, organic EL display devices are self-luminous, have a high-speed response, and are lightweight, and therefore are actively developed as ideal FPDs. Yes.

  The element structure of the organic EL is disclosed in many literatures (see, for example, Non-Patent Document 1), and is classified into a low molecular weight organic EL and a high molecular weight organic EL depending on the material of the organic light emitting layer. As shown in FIG. 1, the basic element structure is a transparent conductive film as an anode electrode layer 2, a hole injection layer 3, a hole transport layer 4, a light emitting layer 5, an electron transport layer on a transparent substrate 1 such as a glass substrate. 6. It has a structure in which metal electrodes as the cathode electrode layer 7 are sequentially laminated. Here, the hole injection layer 3, the hole transport layer 4, the light emitting layer 5, and the electron transport layer 6 are collectively referred to as an organic light emitting layer 8.

  The basic principle of the organic EL is to emit light by conversion into light energy by recombination of holes and electrons performed in the organic light emitting layer 8. The electroluminescent light 9 generated in the light emitting layer 5 is applied as a display element by passing through the transparent substrate 1 and taking it out.

  Moreover, organic EL is divided roughly into two types according to an electric drive system. One is a passive type (dot matrix type) in which a stripe-shaped transparent conductive film and a metal electrode are arranged so as to be orthogonal to each other, and light is emitted at the intersection of the orthogonal stripe-shaped electrodes when a voltage is applied. The other is to form thin film transistors (TFTs) using low-temperature-grown polycrystalline silicon and amorphous silicon TFTs in an array on a transparent substrate, so that only the pixels connected to the on-state TFTs emit light by switching the transistors. Active type.

  In any method, the light emission mechanism of the organic EL element is the same. As described above, the organic EL display element is based on taking out the electroluminescence light 9 emitted from the organic light emitting layer 8 through the anode electrode layer (transparent conductive film) 2 and the transparent substrate 1 and taking it out to the outside. As one of the methods for increasing the light emission luminance, it is required to increase the transmittance of the light emitted from the light emitting layer with respect to the transparent conductive film and the transparent substrate.

The transparent conductive film used in an organic EL, IZO film (indium zinc oxide) was added to ZnO in In ₂ O ₃ on the ITO film added with SnO ₂ (indium-tin oxide film) or In ₂ O _3, Al ₂ There is a ZnO film to which O ₃ (aluminum oxide) or gallium oxide (Ga ₂ O ₃ ) is added.
Monthly Display, Techno Times, September 2003

  However, the organic light-emitting layer 8 (hole injection layer 3, hole transport layer 4, light-emitting layer 5, electron transport layer 6), anode electrode layer (transparent conductive film) 2, and transparent substrate 1 constituting the organic EL element structure. 1 have different refractive indexes, the electroluminescent light 9 emitted in the light emitting layer as shown in FIG. 1 is generated at the interface between the organic light emitting layer 8 and the anode electrode (transparent conductive film) 2, the anode electrode (transparent The light is reflected at the intensity between the conductive film 2 and the transparent substrate 1 due to the difference in refractive index. Since the reflected light 10 causes optical interference, the amount of light emitted to the transparent substrate 1 is reduced, and there is a problem that light emission luminance is lowered or light emission efficiency is lowered.

  In order to improve the decrease in the amount of emitted light due to such an optical interference effect, it is effective to reduce the film thickness of the transparent conductive film, but the electrical resistance of the transparent conductive film is increased and the organic electroluminescence is increased. There arises a problem that the image quality of the sense display is deteriorated.

  The present invention has been made to solve the above-described problems, and an object thereof is to provide an organic electroluminescence display element having an element structure effective for improving light emission luminance or light emission efficiency. .

  The organic electroluminescence device of the present invention comprises an anode electrode layer and an organic light emitting layer, which are substantially transparent to electroluminescence light, sequentially laminated on a transparent substrate, and a cathode electrode layer formed on the anode electrode layer. The surface of the transparent substrate opposite to the surface on which the organic light emitting layer is formed is made to emit light excited by applying a direct current voltage between the electrode layer and the cathode electrode layer and injecting a direct current into the organic light emitting layer. It is configured to be taken out from. In such an organic electroluminescence display device, a light interference layer made of a dielectric material transparent to electroluminescence light is inserted between the transparent substrate and the anode electrode layer.

  By providing the light interference layer, it is possible to provide an organic electroluminescence display device having high light extraction efficiency and a wide viewing angle.

  The optical interference layer is composed of only one transparent dielectric layer, and the dielectric layer has a refractive index of 1.6 to 1.8 at a wavelength of 550 nm and a geometric film thickness of 75 to 85 nm. Is desirable.

  Further, the optical interference layer is constituted by three layers in which two types of transparent dielectric layers having different refractive indexes are alternately laminated, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4. A first dielectric layer having a geometric thickness of 20 nm to 25 nm, a second dielectric layer made of silicon oxide having a geometric thickness of 27 nm to 33 nm, and a refractive index of 2 at a wavelength of 550 nm More preferably, the third dielectric layer having a thickness of 0.0 to 2.4 and a geometric thickness of 32 to 39 nm is stacked in this order.

  Further, the optical interference layer is constituted by four layers in which two types of transparent dielectric layers having different refractive indexes are alternately laminated, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4, a first dielectric layer having a geometric thickness of 14 nm to 18 nm, a second dielectric layer made of silicon oxide having a geometric thickness of 36 nm to 42 nm, and a refractive index of 2 at a wavelength of 550 nm. A third dielectric layer having a geometric thickness of 27 nm to 33 nm and a fourth dielectric layer made of silicon oxide having a geometric thickness of 8 nm to 13 nm are stacked in this order. More preferably.

  Furthermore, the optical interference layer is composed of five layers in which two types of transparent dielectric layers having different refractive indexes are alternately laminated, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4. A first dielectric layer having a geometric thickness of 10 nm to 14 nm, a second dielectric layer made of silicon oxide having a geometric thickness of 44 nm to 50 nm, and a refractive index at a wavelength of 550 nm A third dielectric layer having a geometric film thickness of 30 nm to 38 nm and a fourth dielectric layer made of silicon oxide having a geometric film thickness of 18 nm to 24 nm; a wavelength; Even more preferably, the fifth dielectric layer having a refractive index at 550 nm of 2.0 to 2.4 and a geometric thickness of 39 nm to 47 nm is laminated in this order.

  By providing the optical interference film having the above-described film configuration, an organic electroluminescence display device having high light extraction efficiency and a wide viewing angle can be provided.

Further, it is desirable to insert a layer made of silicon oxide having a geometric film thickness of 10 nm to 50 nm between the transparent substrate and the optical interference layer. By providing this layer, the effect of preventing alkali diffusion from the transparent substrate to the organic light emitting layer and improving the adhesion between the transparent substrate and the light interference layer are produced.
The anode electrode layer is preferably a transparent conductive layer having a geometric film thickness of 80 nm to 110 nm including an indium tin oxide film or an indium zinc oxide film. By constituting the anode electrode layer with these materials, the light transmittance in the anode electrode layer can be increased.

  According to the present invention, an organic electroluminescence display device having high light extraction efficiency and a wide viewing angle can be provided by employing an optical interference film.

  The inventor of the present invention has intensively studied to solve the above problems, and as a result, has found the following. That is, an anode electrode layer, an organic light-emitting layer (a hole injection layer, a hole transport layer, a light-emitting layer, and an electron transport layer) that is substantially transparent to electroluminescence light formed on a transparent substrate, a cathode electrode layer In an organic electroluminescence display device comprising: a single-layer or multi-layered light interference layer made of a dielectric material transparent to electroluminescence light, between a transparent substrate and an anode electrode layer Therefore, the emission wavelength generated when the electroluminescent light generated in the light-emitting layer passes through the light-emitting layer, the anode layer, the light interference layer, and the transparent substrate without impairing the electrical resistance of the anode electrode layer required for driving the light-emitting display. Based on the optical interference effect at, the transmittance is increased and the emission luminance is substantially increased.

Here, the optical interference layer added according to the present invention functions so as to increase the amount of emitted light described above, and is designed to have an optimum structure so that the function is maximized. As the number increases, an excellent function can be obtained.
Hereinafter, an organic electroluminescence display element according to an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 2 is a cross-sectional view schematically showing the structure of the organic electroluminescence display device according to the embodiment of the present invention. In FIG. 2, the organic electroluminescent element 100 includes a transparent conductive film layer as an anode electrode layer 2, a hole injection layer 3, a hole transport layer 4, a light emitting layer 5, an electron transport layer 6 on a transparent substrate 1. A metal film as the cathode electrode layer 7 is provided with a laminated film formed by laminating in this order. The above structure is the same as that of the conventional organic electroluminescence display device shown in FIG. The organic electroluminescence device of the present invention is characterized in that a light interference layer 11 is inserted between the transparent substrate 1 and the anode electrode layer 2. The optical interference layer may be a single layer film or a multilayer film. These laminated films can be formed by a sputtering method, a vacuum deposition method, an ion plating method, or the like in an atmosphere under reduced pressure.

  The organic electroluminescent element 100 is connected to the DC power source 20 via the anode electrode layer 2 and the cathode electrode layer 7 so that a constant current can flow through the organic light emitting layer 8.

The organic electroluminescent element used in order to evaluate the effect of the optical interference layer of the present invention will be described below along the production procedure.
(1) Soda lime glass having a thickness of 0.7 mm is subjected to alkali cleaning and pure water ultrasonic cleaning.
(2) Using the soda lime glass as a substrate, a SiO ₂ film is formed by sputtering from a quartz target in an Ar / O ₂ mixed gas atmosphere with a mixing ratio of 95/5 (flow rate%) to a film thickness of about 30 nm. .
(3) A light interference layer is formed on the SiO ₂ film by sputtering (see the examples described later for the film configuration).

(4) An ITO transparent conductive film having a film thickness of 85 nm is formed on the optical interference layer by sputtering. The sputtering gas was an Ar / O ₂ mixed gas having a mixing ratio of 95/5 (flow rate ratio).
(5) The ITO film is patterned as an anode electrode.
(6) The glass substrate with ITO film is subjected to ultrasonic cleaning using a neutral detergent and alcohol (acetone, ethanol), and after drying, the surface of the ITO film is subjected to ultraviolet light / ozone cleaning.
(7) The glass substrate with the ITO film is inserted into a vacuum vapor deposition apparatus for forming an organic light emitting layer, and the inside of the vacuum vapor deposition apparatus is evacuated to 0.7 × 10 ⁻⁴ Pa or less.

(8) As a hole injection layer on the ITO film, a film of about 4 nm as 4,4 ′, 4 ″ -tris [N- (3methylphenyl) -N-phenylamino] triphenylamine (m-MTDATA) Vapor is deposited to a thickness.
(9) Next, as a hole transport layer, N, N′-diphenyl-N, N′-m-tolyl-4,4 ″ -diamino-1,1′-biphenyl (TPD) is maintained while maintaining a reduced pressure state. Is deposited to a thickness of about 30 nm.

(10) Further, tris (8-quinolinolato) aluminum (Alq3) is vapor-deposited to a film thickness of about 55 nm while maintaining the reduced pressure as the electron transport layer.
(11) Further, an aluminum lithium electrode is formed as an electron injection electrode (cathode electrode) so as to have a film thickness of about 60 nm.
(12) Move the formed glass substrate into a glove box filled with dry air, and use a glass-made sealing container to seal the organic EL layer completely from the outside air. Use to adhere the glass substrate and the sealing container.

A direct-current voltage is applied between the cathode electrode and the anode electrode of the organic electroluminescence element produced by the above process, and the light emission luminance is measured by driving at a constant current density of 10 mA / cm ² .

The additional layer made of SiO ₂ inserted between the transparent substrate and the light interference layer is effective for preventing alkali diffusion from the substrate to the organic electroluminescence layer and improving the adhesion between the transparent substrate and the light interference layer. It is.

  The optical interference layer of the present invention will be described in detail below based on examples. The refractive index of each layer is a value at a wavelength of 550 nm, and the film thickness is a geometric film thickness.

[Example 1]
A single layer film of SiSnOx is used as the optical interference layer. SiSnOx is an oxide of a silicon / tin alloy and has a refractive index of 1.70.
The SiSn metal target was used and formed by reactive sputtering in an Ar / O ₂ mixed gas atmosphere with a mixing ratio of 60/40 (flow rate%). The film thickness was 81 nm.
The film material is not limited to this. For example, Al ₂ O ₃ (refractive index: 1.63) may be used with a film thickness of 84 nm. The Ai ₂ O ₃ film can be formed by reactive sputtering in a Ar / O ₂ mixed gas atmosphere having a mixing ratio of 30/70 (flow rate%) using a metal Al target.

[Example 2]
A first layer contacting a transparent substrate with a high refractive index layer having the following three layers using Ta ₂ O ₅ as a high refractive index material and SiO ₂ as a low refractive index layer. To do.

<First layer>
A Ta ₂ O ₅ (tantalum oxide) film having a refractive index of 2.20 and a film thickness of 22 nm.
A Ta metal target was used and formed by reactive sputtering in an Ar / O ₂ mixed gas atmosphere with a mixing ratio of 30/70 (flow rate%).

<Second layer>
A SiO ₂ film having a refractive index of 1.46 and a film thickness of 30 nm.
A Si metal target (B-doped) was used and formed by reactive sputtering in an Ar / O ₂ mixed gas atmosphere having a mixing ratio of 30/70 (flow rate%).

<Third layer>
The same Ta ₂ O ₅ film as the first layer, and the film thickness was 35 nm. The film forming method is the same as that for the first layer.

[Example 3]
In the four-layer structure of Ta ₂ O ₅ / SiO ₂ / Ta ₂ O ₅ / SiO _2, a layer having a high refractive index is a first layer in contact with the transparent substrate. The film configuration is as shown below. The method for forming each layer is the same as that in the second embodiment.

<First layer>
Ta ₂ O ₅ film, film thickness: 16 nm
<Second layer>
SiO ₂ film, film thickness: 39 nm
<Third layer>
Ta ₂ O ₅ film, film thickness: 30 nm
<Fourth layer>
SiO ₂ film, film thickness: 11 nm

[Example 4]
In the five-layer structure of Ta ₂ O ₅ / SiO ₂ / Ta ₂ O ₅ / SiO ₂ / Ta ₂ O ₅ , the layer having a high refractive index is the first layer in contact with the transparent substrate. The film configuration is as shown below. The method for forming each layer is the same as that in the second embodiment.

<First layer>
Ta ₂ O ₅ film, film thickness: 12 nm
<Second layer>
SiO ₂ film, film thickness: 47 nm
<Third layer>
Ta ₂ O ₅ film, film thickness: 34 nm
<Fourth layer>
SiO ₂ film, film thickness: 21 nm
Film thickness <18nm-24nm>
<5th layer>
Ta ₂ O ₅ film, film thickness: 43 nm

  In Examples 2 to 4, tantalum oxide was used as the high refractive index material, but the present invention is not limited to this. Titanium oxide (refractive index 2.40), titanium tantalum composite oxide (refractive index 2.35), niobium oxide (refractive index 2.25), zirconium oxide (refractive index 2.10), or the like can be used. In the case of organic EL, since it is desirable to improve the interface flatness between the organic EL layer and the transparent conductive film, the light interference layer material is preferably a material having an amorphous structure, such as tantalum oxide or titanium tantalum composite oxide. Particularly preferred are niobium oxide and the like.

  The light emission luminance of the organic electroluminescence device using the optical interference film of each of the above examples was measured. The results are shown in Table 1. In any case, a luminance improvement effect of 10% or more could be confirmed as compared with the case without the light interference layer (shown as a comparative example in the table).

In the present invention, the principle that the light extraction efficiency is increased by the light interference layer is that light emitted from the light emitting layer by the newly added light interference layer is reflected at the interface between the organic EL layer / transparent conductive layer, the transparent conductive film / This is to reduce reflection at the interface with the glass substrate and prevent transmission loss. Glass substrate (refractive index of 1.46 to 1.52) / transparent conductive film (refractive index: 1.90 to 1.95, film thickness of 80 nm to 110 nm) / organic light emitting layer (refractive index of about 1.8 as a whole) In the structure of the structure, which can be regarded as a light emission, when an emission medium is considered, an incident medium (= organic light emitting layer, n = 1.8), an emission medium (= glass substrate, n = 1.46 to 1.52),
Assuming an optical structure of incident medium / transparent conductive film / light interference layer / output medium, an optical matching layer (matching layer = antireflection layer) between the incident medium and output medium in both the transparent conductive film and the light interference layer. ) Is the basic idea.

  In addition, since light emitted from the light emitting layer is emitted in all directions from the light emitting point in the light emitting layer, when the optical matching layer is formed, the incident angle of light incident on the transparent conductive film from the incident medium The optimum structure of the optical interference layer was determined so that the antireflection conditions were all satisfied in the range of 0 ° to ± 30 °. This corresponds to Examples 1 to 4. By establishing the antireflection condition in this wide incident angle range, the efficiency of extracting light emitted from the light emitting layer to the outside can be increased. Further, it is possible to reduce the viewing angle dependency when the viewer looks at the display element.

  The number of optical interference layers can be realized in principle even if the number of layers is increased, but the improvement effect is only slightly increased even from the viewpoint of manufacturing cost and the number of layers of 5 layers or more. Then, the maximum was 5 layers.

  The basic structure of the optical interference layer is an alternating laminate of two transparent thin films having different refractive indexes. In the case of Example 1, it is a special case, and it is necessary to have an intermediate refractive index between the transparent conductive film and the glass substrate. Reflection can be suppressed. When the refractive index is smaller than 1.6, the refractive index difference with the transparent conductive film is increased, and the interface reflection is increased.

  On the other hand, if the refractive index is higher than 1.8, the difference in refractive index from the glass substrate increases, and the reflection intensity increases. The antireflection condition necessary for the optical interference layer in Example 1 can be derived from the optical film design based on Maxell's electromagnetic equation in the optical structure described above, and the optimal solution is the optical film thickness (refractive index × geometry). The film thickness is 136.5 nm.

  Since the optimum range of the refractive index is 1.6 to 1.8, the geometric film thickness is in the range of 75 nm to 85 nm. When the film thickness is out of this range, that is, when the film thickness is smaller than 75 nm, or when the film thickness is larger than 85 nm, the antireflection condition is lost, so the reflectance reduction effect is reduced, and as a result, the light extraction effect Will become smaller.

Next, the grounds for limiting the refractive index and film thickness when the optical interference layer in Examples 2 to 4 has a multilayer structure will be described. In the present invention, the low refractive index material is limited to silicon oxide (SiO ₂ ). The reason is that it is an inorganic material film having an amorphous structure, and a thin film having a smooth surface is obtained, which is desirable for an organic electroluminescence device.

When an antireflection structure is formed by an alternately laminated structure of a low refractive index layer and a high refractive index layer, the refractive index ratio of both materials is important. When the refractive index of the high refractive index material is smaller than 2.0, the refractive index ratio with SiO ₂ becomes small, the reflection intensity at the multilayer film interface is lowered, and a sufficient optical interference effect (antireflection effect) cannot be obtained. In order to obtain a sufficient optical interference effect, it is necessary to increase the number of stacked layers, which increases the manufacturing cost, which is not preferable.

On the other hand, if the refractive index is larger than 2.4, the refractive index ratio with SiO ₂ becomes too large, so that the reflection intensity at the multilayer film interface becomes too strong, and a sufficient optical interference effect (antireflection effect) is obtained. Not preferable. In this case as well, an operation of increasing the number of stacked layers and increasing the degree of freedom of interference is necessary to obtain a sufficient optical interference effect, which is not suitable for the purpose of the present invention from the viewpoint of manufacturing cost.

Therefore, the refractive index range of 2.0 to 2.4 is desirable as the refractive index necessary for the high refractive index material of the optical interference layer in Examples 2 to 4. Regarding the limitation of the film thickness, in the same manner as in Example 1, in the optical structure described above, an optimum solution for obtaining an excellent antireflection performance with a small total film thickness of the optical interference layer was derived, and each layer obtained A desirable geometric film thickness range is determined from the optimal solution of the optical film thickness and the above-described refractive index range of the high refractive index material. The geometrical film thickness range of the SiO ₂ film, for the refractive index of the SiO ₂ film is small, from the geometric film thickness optimal solutions (design center), a large influence on the characteristics if it is within ± 3 nm It can be said not to give.

  As the transparent substrate that can be used in the present invention, soda lime glass, alkali-free glass, quartz glass, and the like, which are used for normal display applications, can be applied, and a transparent resin substrate can also be applied. The refractive index range is desirably 1.46 to 1.55.

It is a cross-sectional schematic diagram of the conventional organic electroluminescent display apparatus. It is a cross-sectional schematic diagram of the organic electroluminescent display apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transparent substrate 2 Anode electrode layer 3 Hole injection layer 4 Hole transport layer 5 Light emitting layer 6 Electron transport layer 7 Cathode electrode layer 8 Organic light emitting layer 9 Electroluminescence light 10 Reflected light 11 Optical interference layer 20 DC power supply 100 Organic electro Luminescence element

Claims (7)

An anode electrode layer and an organic light emitting layer that are substantially transparent to electroluminescence light are sequentially laminated on a transparent substrate, and a cathode electrode layer is further formed thereon, and the anode electrode layer is interposed between the anode electrode layer and the cathode electrode layer. An organic electroluminescence display that takes out light excited and emitted by applying a direct current voltage and applying a direct current to the organic light emitting layer from a surface of the transparent substrate opposite to the surface on which the organic light emitting layer is formed. In the device, an organic electroluminescence display device, wherein a light interference layer made of a dielectric material transparent to electroluminescence light is inserted between the transparent substrate and the anode electrode layer. The optical interference layer is composed of only one transparent dielectric layer, and the dielectric layer has a refractive index of 1.6 to 1.8 at a wavelength of 550 nm and a geometric film thickness of 75 to 85 nm. The organic electroluminescence display device according to claim 1. The optical interference layer is composed of three layers in which two types of transparent dielectric layers having different refractive indexes are alternately stacked, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4 and a first dielectric layer having a geometric film thickness of 20 nm to 25 nm, a second dielectric layer made of silicon oxide having a geometric film thickness of 27 nm to 33 nm, and a refractive index at a wavelength of 550 nm. 2. The organic electroluminescence display device according to claim 1, wherein a third dielectric layer having a geometric film thickness of 32 nm to 39 nm and a thickness of 2.0 to 2.4 is laminated in that order. The optical interference layer is composed of four layers in which two types of transparent dielectric layers having different refractive indexes are alternately stacked, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4 and a first dielectric layer having a geometric thickness of 14 nm to 18 nm, a second dielectric layer made of silicon oxide having a geometric thickness of 36 nm to 42 nm, and a refractive index at a wavelength of 550 nm. A third dielectric layer having a geometric thickness of 27 nm to 33 nm and a fourth dielectric layer made of silicon oxide having a geometric thickness of 8 nm to 13 nm are stacked in this order. The organic electroluminescence display device according to claim 1, wherein the organic electroluminescence display device is provided. The optical interference layer is composed of five layers in which two types of transparent dielectric layers having different refractive indexes are alternately stacked, and the dielectric layer has a refractive index of 2.0 to 2 at a wavelength of 550 nm from the transparent substrate side. 4. A first dielectric layer having a geometric thickness of 10 nm to 14 nm, a second dielectric layer made of silicon oxide having a geometric thickness of 44 nm to 50 nm, and a refractive index at a wavelength of 550 nm A third dielectric layer having a geometric film thickness of 30 nm to 38 nm and a fourth dielectric layer made of silicon oxide having a geometric film thickness of 18 nm to 24 nm; a wavelength; 2. The organic electroluminescence according to claim 1, wherein a fifth dielectric layer having a refractive index at 550 nm of 2.0 to 2.4 and a geometric thickness of 39 nm to 47 nm is laminated in this order. Sense display device. 6. The organic electroluminescence according to claim 1, wherein a layer made of silicon oxide having a geometric film thickness of 10 nm to 50 nm is inserted between the transparent substrate and the optical interference layer. Display device. The organic electro layer according to claim 1, wherein the anode electrode layer is a transparent conductive layer having a geometric film thickness of 80 nm to 110 nm including an indium tin oxide film or an indium zinc oxide film. Luminescence display device.

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