JP2003109747A - Organic surface electroluminescent emitting device and liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic surface electroluminescent emitting device body which realizes a high light output efficiency in a simple structure. SOLUTION: A positive electrode 2, an organic light emitting layer 3 and a negative electrode 4 are fitted in that order on one face of a transparent substrate. Then, a light-diffusion part 5 with haze of 80% or more is fitted to the face opposite to the positive electrode of the transparent substrate. Total reflection of the light at the interface with air is lessened to a great degree by light scattering effect of the light diffusion part 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence surface light emitter used for a liquid crystal backlight, a lighting fixture, and the like, and a liquid crystal display device using the organic electroluminescence surface light emitter as a backlight. .

[0002]

2. Description of the Related Art Research on electroluminescent elements using organic materials has been attracting attention for a long time and various studies have been conducted, but since the luminous efficiency is very poor, it was not possible to carry out full-scale practical studies. . However, in 1987, Kodak C.I. W. Tang et al. Proposed organic electroluminescence having a function-separated layered structure in which an organic material is divided into two layers, a hole transport layer and a light emitting layer.
It was revealed that a high emission luminance of 000 cd / m ² or more can be obtained. Since then, attention has been paid to organic electroluminescence devices, and active research has been conducted.

As a result of such research and development, the organic electroluminescence device is capable of high-luminance surface emission of about 100 to 100,000 cd / m ² at a low voltage of about 10 V, and the type of fluorescent substance is selected. This made it possible to emit light from blue to red.

Under such a trend, as practical use approaches, further improvement in luminous efficiency is desired. That is, the organic electroluminescence element is formed as an organic electroluminescence surface light emitter by providing an anode, an organic light emitting layer, and a cathode in this order on the surface of one side of the transparent substrate. The light emitted from the organic light emitting layer by applying a voltage between the anode and the cathode is extracted through the transparent substrate. In this way, when the light is taken out from the transparent substrate to the outside, it is unavoidable that total internal reflection occurs at the interface between the surface of the transparent substrate and the external air, and when a glass plate is used as the transparent substrate in the organic electroluminescent surface light emitter, At present, the light extraction efficiency is as low as about 20%.

[0005]

As a technique for improving the light extraction efficiency from a transparent substrate, a method of introducing a micro-resonant structure by processing a dielectric reflecting mirror on the transparent substrate,
There are methods such as arranging microlenses on the transparent substrate and inserting a high refractive index layer at the interface between the transparent substrate and the element. However, all of these require strict optical design, Considering the technology, it lacked practicality.

As a simpler technique, Japanese Patent Laid-Open No. 2000-2000
Japanese Patent Laid-Open No. 323272 discloses a method of disposing a diffusing plate having concavities and convexities on a substrate through a medium made of optical oil such as silicone oil. However, in this case, the medium material is a liquid, which makes it difficult to handle, and thus has a problem in practical use.

The present invention has been made in view of the above points, and it is an object of the present invention to provide an organic electroluminescent surface light-emitting device having a simple structure and capable of obtaining high light extraction efficiency. Another object of the present invention is to provide a liquid crystal display device in which the organic electroluminescence surface light-emitting body is used as a backlight to improve the light utilization efficiency.

[0008]

The organic electroluminescent surface light emitting device according to claim 1 of the present invention comprises a transparent substrate 1
The anode 2, the organic light emitting layer 3, and the cathode 4 are provided in this order on one surface of the transparent substrate 1, and the haze of 80 is provided on the surface of the transparent substrate 1 opposite to the anode 2.
% Or more of the light diffusion portion 5 is provided.

According to a second aspect of the present invention, in the first aspect, the light diffusing portion 5 is formed by scattering the scattering material 7 having a refractive index different from that of the mother layer 6 in the transparent mother layer 6. It is characterized by.

Further, the invention of claim 3 is the method according to claim 1 or 2, wherein a sheet 8 having a scattering material 7 having a refractive index different from that of the mother layer 6 in the transparent mother layer 6 is attached to the surface of the transparent substrate 1. As a result, the sheet 8 is provided with the light diffusion portion 5 on the surface of the transparent substrate 1 opposite to the anode 2.

Further, the invention of claim 4 is characterized in that, in any one of claims 1 to 3, a light condensing portion 9 for condensing light is provided on a surface of the light diffusing portion 5 opposite to the transparent substrate 1. It is characterized by.

An organic electroluminescent surface light emitting device according to a fifth aspect of the present invention is characterized in that an anode 2, an organic light emitting layer 3 and a cathode 4 are provided in this order on a transparent substrate 1 having a haze of 80% or more. To do.

According to a sixth aspect of the present invention, in the fifth aspect, the transparent substrate 1 is formed by scattering the scattering material 7 having a refractive index different from that of the mother layer 6 in the transparent mother layer 6. It is a feature.

In the liquid crystal display device according to claim 7 of the present invention, the liquid crystal element 10 is arranged outside the transparent substrate 1 of the organic electroluminescent surface light emitting device according to any one of claims 1 to 6. It is characterized by being provided

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 shows an example of an embodiment of the present invention. An anode 2, an organic light emitting layer 3 and a cathode 4 made of a transparent conductive film are laminated in this order on one surface of a transparent substrate 1, and further, A light diffusion portion 5 is provided on the surface of the transparent substrate 1 opposite to the anode 2. As the transparent substrate 1, a transparent glass plate such as soda lime glass or non-alkali glass, or a transparent plastic plate can be used. The transparent substrate 1 need only be light-transmissive, and in addition to being colorless and transparent, it may be slightly colored or frosted glass-like.

As the anode 2, cathode 4 and organic light emitting layer 3, those conventionally used in organic electroluminescence devices can be used as they are. The organic light emitting layer 3 is formed in a multilayer structure in which a hole transport layer is laminated on the anode 2 side and an electron transport layer is laminated on the cathode 4 side. A positive voltage is applied to the anode 2 and a negative voltage is applied to the cathode 4. When applied, the electrons injected through the electron transport layer and the holes injected through the hole transport layer are combined in the organic light emitting layer 3 to emit light. Thus, the light emitted from the organic light emitting layer 3 passes through the anode 2 made of a transparent conductive film and the transparent substrate 1 and is extracted from the surface of the light diffusing section 5.

Here, as the light diffusing section 5, one having a haze (cloudiness value) of 80% or more is used, and the light transmitted through the light diffusing section 5 is caused by the light scattering effect.
The total reflection at the interface between the surface and the air is extremely reduced, and the light is efficiently extracted from the light diffusion portion 5. If the haze of the light diffusing section 5 is less than 80%, a sufficient light scattering effect cannot be obtained, and a clear improvement in the light extraction rate cannot be obtained. In the present invention, the upper limit value of the haze of the light diffusing portion 5 is not particularly limited, but if the haze becomes too high, the front luminance may decrease, so it is preferably 95% or less.

The light diffusing portion 5 can be formed by dispersing and scattering the light scattering material 7 having a refractive index different from that of the mother layer 6 in the mother layer 6. Due to the difference in the refractive index of the scattering material 7, the light can be diffused as a whole by the reflection and refraction of the light at the interface between the mother layer 6 and the light scattering material 7. The mother layer 6 has a refractive index equivalent to that of the transparent substrate 1 or a refractive index larger than that of the transparent substrate 1 so that the mother layer 6 is transparent to visible light, and total reflection does not easily occur at the interface with the transparent substrate 1. It is preferable to use a resin having a specific ratio, and the material is not particularly limited as long as it maintains a fixed shape. For example, acrylic resin, PET, epoxy resin, silicon resin, cycloolefin polymer, nylon, polycarbonate resin, fluorine resin One or more transparent resins selected from the above can be appropriately selected and used. The thickness of the mother layer 6 that forms the diffusion portion 5 is not particularly limited as long as it is a thickness that can ensure transparency with respect to visible light. The scattering material 7 may be any material that does not absorb light and has a refractive index different from that of the base layer 6, and the material and shape are not particularly limited. For example, silica, titania, barium sulfate, calcium carbonate, etc. are used. You can Mother layer 6
The amount of the light scattering material 7 added to the
It is appropriately set according to the value of haze.

In the embodiment shown in FIG. 1, the light diffusing portion 5 is formed by applying a resin liquid, which is a mixture of a resin to be the mother layer 6 and the light scattering material 7, onto the surface of the transparent substrate 1 and curing or solidifying the same. The light diffusing portion 5 is integrally provided on the transparent substrate 1 by forming the light diffusing portion 5, but in the embodiment of FIG. 2, the light diffusing portion 5 is formed by the sheet 8 which is separate from the transparent substrate 1. Sheet 8
By adhering to the transparent substrate 1 with the adhesive 12,
A light diffusing portion 5 is provided on the surface of the transparent substrate 1 opposite to the anode 2. Other configurations are the same as those in FIG. The sheet 8 can be formed by scattering the light scattering material 7 having a refractive index different from that of the mother layer 6 in the mother layer 6 formed of a transparent resin or the like, as described above. A commercially available diffusion film for a liquid crystal backlight film can be used. Here, as the adhesive 12 for adhering the light diffusion portion 5 made of the sheet 8 to the transparent substrate 1, a material having a function similar to that of the mother layer 6 is preferable.

FIG. 3 shows another example of the embodiment of the present invention, in which a light converging portion 9 is provided on the surface of the light diffusing portion 5 opposite to the transparent substrate 1. Other configurations are the same as those in FIGS. 1 and 2. Since the light extracted from the light diffusing section 5 is in a scattered state, in the case of FIG. 3, the light exiting from the light diffusing section 5 is condensed by the condensing section 9 so as to increase the front luminance of the surface light emitter. I am doing it. The condensing part 9 can be formed by a lens having a shape designed to collect the light emitted from the light diffusing part 5.

In the embodiment shown in FIG. 4, the transparent substrate 1 itself is formed of a material having a light diffusing property of haze of 80% or more. Other configurations are the same as those described above. If the haze of the transparent substrate 1 is 80% or more (the upper limit is preferably 95% as described above), the light transmitted through the transparent substrate 1 is totally reflected at the interface with the air due to the light scattering effect. Therefore, the light can be extracted efficiently from the transparent substrate 1. Therefore, in this case, it is not necessary to provide the light diffusion section 5. The transparent substrate 1 having a haze of 80% or more should be formed by dispersing and scattering the light scattering material 7 having a refractive index different from that of the mother layer 6 in the mother layer 6, as in the case of the light diffusion portion 5. You can

As described above, in the surface light emitter of the present invention,
Since the light is taken out in a diffused state, even if at least a part of the anode 2 or the cathode 4 is patterned and there is a non-light emitting portion, the surface emitting light is uniformly emitted by the light diffusion effect. You can get a body.

Next, a liquid crystal display device using the organic electroluminescent surface light emitting device A formed as described above as a backlight will be described. FIG. 5 shows an example of the embodiment, and the outside of the light diffusion portion 5 of the organic electroluminescence surface light emitting device A (the transparent substrate 1 is formed to have a haze of 80% or more and the light diffusion portion 5 is not provided). In this case, the liquid crystal display device is formed by disposing the liquid crystal element 10 on the outer side of the transparent substrate 1).

In this liquid crystal display device, when the surroundings are dark, the organic electroluminescent surface light emitter A functions as a backlight, and the liquid crystal element 10 emits light of the organic electroluminescence surface light emitter A as indicated by an arrow.
By transmitting the light from the back side, the liquid crystal display can be performed by efficiently utilizing the light emission. When the surroundings are bright, external light from the surroundings passes through the liquid crystal element 10 and reaches the light diffusing portion 5 (or the transparent substrate 1 having a haze of 80% or more) of the organic electroluminescent surface light emitting device A, and the arrow mark As described above, a part of this light is reflected by the light diffusing portion 5 (or the transparent substrate 1) and transmitted through the liquid crystal element 10 from the back side, whereby liquid crystal display can be performed. The light transmitted through (or the transparent substrate 1) is reflected by the cathode 4 as a reflective electrode,
The liquid crystal display can be performed by transmitting the liquid crystal element 10 from the back side as shown by the arrow C.

In this way, when the surroundings are dark, the organic electroluminescent surface light-emitting body A can be used as a backlight to emit light for liquid crystal display, and when the surroundings are bright, ambient light from the surroundings can be emitted. By reflecting the light on the light diffusing portion 5 (or the transparent substrate 1 having a haze of 80% or more) of the organic electroluminescent surface light emitter A, liquid crystal display can be performed without the need to cause the organic electroluminescent surface light emitter A to emit light. Therefore, a liquid crystal display device having high light utilization efficiency can be obtained. An example in which an organic electroluminescence element is applied as a liquid crystal backlight is disclosed in Japanese Patent Laid-Open No. 10-125461. In this example, the organic electroluminescence element has a light diffusing portion 5 (or a haze of 80). % Of the transparent substrate 1), which has a general structure without a transparent substrate 1), is simply combined with a liquid crystal element. On the other hand, the organic electroluminescence surface light-emitting body A of the present invention has the light diffusion portion 5
By providing (or the transparent substrate 1 having a haze of 80% or more), it is possible to obtain a liquid crystal display device having excellent light extraction efficiency as described above and having extremely high efficiency as a backlight. It is a thing.

Here, the liquid crystal element 10 used in the present invention is not particularly limited, but it is formed by providing a half mirror for controlling reflection / transmission in the liquid crystal element 10 and when the surroundings are bright. Can use a semi-transmissive liquid crystal that does not require a light source, or a transmissive liquid crystal that does not have a reflection function inside the liquid crystal element 10 and always needs a light source when performing liquid crystal display. The backlight composed of the organic electroluminescence surface light emitting device A according to the present invention can reflect ambient light by the light diffusing portion 5 (or the transparent substrate 1 having a haze of 80% or more) to display a liquid crystal. Therefore, it is more preferable to combine with a transmissive liquid crystal element. When the backlight composed of the organic electroluminescent surface light emitting device A of the present invention is combined with a transmissive liquid crystal element, it can be used like a semi-transmissive liquid crystal. In the case of transmissive liquid crystal, the transmittance of the liquid crystal element is higher than that of semi-transmissive liquid crystal, so
The light from the organic electroluminescence surface light-emitting body A can be efficiently transmitted to the liquid crystal element, and the light can be efficiently used for liquid crystal display.

The backlight made of the organic electroluminescence surface light-emitting body A and the liquid crystal element may be separated independently, but it is preferable to use the two in close contact with each other because the utilization efficiency of light is excellent. .

[0029]

EXAMPLES Next, the present invention will be specifically described with reference to examples.

Example 1 ITO (indium-tin oxide) was sputtered on the surface of a transparent substrate 1 made of a glass plate having a thickness of 0.7 mm to form an anode 2 having a sheet resistance of 7Ω / □. First, using ITO glass manufactured by Vacuum Co., Ltd., this was subjected to ultrasonic cleaning with acetone, pure water and isopropyl alcohol for 15 minutes, then dried, and further subjected to UV ozone cleaning.

Next, a UV curable transparent resin ("KZ9752" manufactured by JSR Co., Ltd .: refractive index 1.53) and silica particles ("High Presica UFN3N" manufactured by Ube Nitto Kasei Co., Ltd .: refractive index 1) at a ratio of 20% by volume. .35 to 1.45, average particle size 7.0 μm) was mixed and prepared to a thickness of 300 μm on the surface of the transparent substrate 1 on the side opposite to where the anode 2 was formed, and UV irradiation was performed. By curing
The light diffusion portion 5 having a haze of 88% was formed.

Next, this substrate is set in a vacuum vapor deposition apparatus,
Under reduced pressure of 1 × 10 ⁻⁶ Torr (1.33 × 10 ⁻⁴ Pa), 4,4′-bis [N- (naphthyl) -N-phenyl-amino] biphenyl (manufactured by Dojindo Laboratories Ltd.) To
A hole transport layer is formed on the anode 2 by vapor deposition at a vapor deposition rate of 1 to 2 Å / s to a thickness of 400 Å, and then tris (8-hydroxyquinolinato) aluminum complex (manufactured by Dojindo Laboratories Ltd.) Was vapor-deposited at a vapor deposition rate of 1 to 2 Å / s to a thickness of 400 Å to form a layer serving as both a light emitting layer and an electron transporting layer on the hole transporting layer, and an organic light emitting layer 3 was provided.

Then, LiF is vapor-deposited at a vapor deposition rate of 0.5 to 1.0 Å to a thickness of 5 Å, and then Al is vaporized at 10 Å /
By depositing a thickness of 1500Å at a deposition rate of s,
A cathode 4 was formed on the organic light emitting layer 3 to produce an organic electroluminescent surface light emitter having a structure shown in FIG.

(Example 2) Diffusion film ("Opalus BS-04" manufactured by Keiwa Co., Ltd .: haze 89.5%, thickness 1)
2) in the same manner as in Example 1 except that 40 μm) was attached to the surface of the transparent substrate 1 opposite to the side where the anode 2 was formed with an epoxy adhesive 12 to provide the light diffusing portion 5. The organic electroluminescent surface light-emitting body of was produced.

(Example 3) Silica particles ("High-Presica UFN3N" manufactured by Ube Nitto Kasei Co., Ltd .: refractive index 1.35 to 1.45, average particle size 7.0 [mu] m) in PET resin at a ratio of 15% by volume. Thickness of composite resin prepared by mixing
A transparent substrate 1 having a haze of 88% was produced by forming a film having a thickness of 50 μm. ITO (Indium-Tin Oxide) is sputtered on the surface of the transparent substrate 1 to form a sheet resistance 30.
An Ω / □ anode 2 was formed, and thereafter, in the same manner as in Example 1, an organic electroluminescent surface light emitting device having the structure shown in FIG. 4 was produced.

(Comparative Example 1) An organic electroluminescence surface light-emitting body was produced in the same manner as in Example 1 except that the light diffusion portion 5 was not formed.

(Comparative Example 2) By setting the addition amount of silica particles to 1% by volume, the haze of the light diffusing portion 5 is set to 30.
An organic electroluminescent surface light emitting device having the structure shown in FIG. 1 was produced in the same manner as in Example 1 except that the percentage was set to%.

The organic electroluminescent surface light-emitting devices produced in Examples 1 to 3 and Comparative Examples 1 and 2 were connected to a power source (KEYTHLEY236 model), and the front luminance when a voltage of 7 V was applied was measured by a luminance meter (Minolta Co., Ltd.). "LS-11
0 "). Then, relative brightness is shown in Table 1 when the brightness obtained in Comparative Example 1 is 1.0.

[0039]

[Table 1]

As can be seen from Table 1, the brightness of each example is improved, and it is confirmed that the light extraction efficiency can be increased.

(Example 4) In the same manner as in Example 1, a light diffusing portion 5 was formed on an ITO glass manufactured by Sanyo Vacuum Co., Ltd. Next, the ITO glass having the light diffusing portion 5 formed thereon was set in a vacuum vapor deposition apparatus, and 1 × 10 ⁻⁶ Torr (1.33 × 10 ⁻⁴ P
Under reduced pressure of a), 4,4'-bis [N- (naphthyl) -N
-Phenyl-amino] biphenyl (hereinafter abbreviated as α-NPD) (manufactured by Dojindo Laboratories Co., Ltd.) was vapor-deposited to a thickness of 300 Å at an evaporation rate of 1 to 2 Å / s to form a hole transport layer on the anode 2. Was formed. Next, on the hole-transporting layer, a layer of α-NPD doped with rubrene (manufactured by ACROSS Co., Ltd.) in an amount of 1% by mass was used as a yellow light emitting layer with a thickness of 100 Å, and as a blue light emitting layer, a distyryl biphenyl derivative (“DPVB manufactured by Idemitsu Kosan Co., Ltd.”) was used.
The organic light emitting layer 3 was provided by laminating a layer in which 12% by mass of a DSA derivative having a carbazolyl group at the end (“BCzVBi” manufactured by Idemitsu Kosan Co., Ltd.) was added to i ″) at a thickness of 500 Å.

Next, on the organic light emitting layer 3, bathophenanthroline (manufactured by Dojindo Laboratories Co., Ltd.) and Cs were co-deposited at a molar ratio of 1: 1 to a thickness of 200Å to form an electron transport layer.
Subsequently, Al is deposited on this at a deposition rate of 10Å / s to a thickness of 1
The cathode 4 was formed by vapor deposition of 500 Å to prepare a white organic electroluminescent surface light-emitting body having the structure shown in FIG.

By disposing the transmissive TFT liquid crystal element 10 outside the light diffusing portion 5 of the thus obtained white organic electroluminescent surface light-emitting device A, a liquid crystal display device having a structure as shown in FIG. 5 is obtained. It was

In this liquid crystal display device, when a voltage of 4.5 V was applied to the white organic electroluminescent surface light-emitting body A, a brightness of 1000 cd / m ² was obtained, and the liquid crystal display portion of the transmissive TFT liquid crystal element 10 was operated. The brightness was 100 cd / m ² . If the surroundings are bright,
The liquid crystal display of the transmissive TFT liquid crystal element 10 can be sufficiently recognized even when the white organic electroluminescence surface light-emitting body A is not made to emit light.

(Comparative Example 3) A white organic electroluminescent surface luminescent material A was prepared in the same manner as in Example 4 except that the light diffusing portion 5 was not formed, and a liquid crystal display was prepared in the same manner as in Example 4. I got the device.

In this liquid crystal display device, when a voltage of 4.5 V was applied to the white organic electroluminescent surface light-emitting body A, a brightness of 650 cd / m ² was obtained, and the liquid crystal display portion of the transmissive TFT liquid crystal element 10 was operated. The brightness was 65 cd / m ² . Further, if the white organic electroluminescent surface light-emitting body A is not made to emit light when the surroundings are bright, the liquid crystal display of the transmissive TFT liquid crystal element 10 cannot be sufficiently recognized.

[0047]

As described above, in the organic electroluminescent surface light emitting device according to claim 1 of the present invention, the anode, the organic light emitting layer and the cathode are provided in this order on one surface of the transparent substrate, and the side opposite to the anode of the transparent substrate is provided. Since a light diffusing portion having a haze of 80% or more is provided on the surface of the, the total scattering of light at the interface with the air can be extremely reduced by the light scattering effect of the light diffusing portion. The light can be efficiently extracted from the diffusion portion, and the light extraction efficiency can be obtained with a simple structure.

According to the invention of claim 2, the light diffusing portion is formed by scattering the scattering material having a refractive index different from that of the mother layer in the transparent mother layer. The light diffusing portion can be formed with such a structure.

According to a third aspect of the present invention, a sheet in which a scattering material having a refractive index different from that of the mother layer is scattered is attached to the surface of the transparent substrate, so that the transparent substrate is provided on the side opposite to the anode of the transparent substrate. Since the light diffusing portion is provided on the surface, the light diffusing portion can be formed as an independent member separate from the transparent substrate,
This increases the degree of freedom in design.

Further, according to the invention of claim 4, a light condensing portion for condensing light is provided on the surface of the light diffusing portion opposite to the transparent substrate. Therefore, the light diffused by the light diffusing portion is condensed. Therefore, the brightness can be increased.

In the organic electroluminescent surface light emitting device according to the fifth aspect of the present invention, since the anode, the organic light emitting layer and the cathode are provided in this order on the transparent substrate having a haze of 80% or more,
The total scattering of light at the interface between the surface of the transparent substrate and the air is extremely reduced by the light scattering effect, and the light can be extracted with high efficiency. Therefore, it is necessary to use a member for light diffusion. It is a simple structure with no light and can obtain high light extraction efficiency.

Further, according to the invention of claim 6, the transparent substrate is formed by interspersing a scattering material having a refractive index different from that of the mother layer in a transparent mother layer. The structure can form the light diffusing portion.

Further, a liquid crystal display device according to a seventh aspect of the present invention is characterized in that, on the outer side of the transparent substrate of the organic electroluminescent surface light emitting device according to any one of the first to sixth aspects,
Since the liquid crystal element is arranged and provided, when the surroundings are dark, it is possible to perform liquid crystal display by emitting light from the organic electroluminescent surface light emitting body as a backlight, and when the surroundings are bright, the By reflecting external light on the light diffusing portion of the organic electroluminescence surface light emitter or the transparent substrate having a haze of 80% or more, liquid crystal display can be performed without the need to cause the organic electroluminescence surface light emitter to emit light. Therefore, it is possible to obtain a liquid crystal display device having high light utilization efficiency.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an example of an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view showing another example of the embodiment of the present invention.

FIG. 4 is a schematic cross-sectional view showing another example of the embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view showing an example of an embodiment of a liquid crystal display device according to the present invention.

[Explanation of symbols]

1 transparent substrate 2 anode 3 Organic light emitting layer 4 cathode 5 Light diffuser 6 mothers 7 Scatterer 8 seats 9 Light collecting section 10 Liquid crystal element

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhisa Kishigami             1048, Kadoma, Kadoma-shi, Osaka Matsushita Electric Works Co., Ltd.             Inside the company F-term (reference) 2H091 FA26X FA41Z LA18                 3K007 AB02 AB03 BB06 CA01 CB01                       DA01 DB03 EA01 EB00 FA01                 5G435 AA03 BB12 BB15 EE26 FF06                       FF07 FF12 GG25 HH04 KK07

Claims (7)

[Claims] 1. An anode, an organic light emitting layer, and
Provide the cathode in this order, on the surface of the transparent substrate opposite to the anode,
An organic electroluminescent surface light-emitting device, characterized by comprising a light diffusing portion having a haze of 80% or more. 2. The organic electroluminescence surface emitting device according to claim 1, wherein the light diffusing portion is formed by scattering a scattering material having a refractive index different from that of the mother layer in a transparent mother layer. body. 3. A sheet in which a scattering material having a refractive index different from that of the mother layer is scattered in a transparent mother layer is attached to the surface of the transparent substrate, so that the surface of the transparent substrate opposite to the anode is exposed to light by this sheet. The diffusion part is provided, The claim 1 or 2 characterized by the above-mentioned.
The organic electroluminescent surface light-emitting device according to. 4. The surface of the light diffusing section opposite to the transparent substrate,
4. The organic electroluminescent surface light emitting device according to claim 1, further comprising a light condensing unit that condenses light. 5. An organic electroluminescent surface light emitter comprising a transparent substrate having a haze of 80% or more, and an anode, an organic light emitting layer and a cathode provided in this order. 6. The organic electroluminescent surface light emitting device according to claim 5, wherein the transparent substrate is formed by scattering a scattering material having a refractive index different from that of the mother layer in a transparent mother layer. . 7. A liquid crystal display device, comprising a liquid crystal element disposed outside a transparent substrate of the organic electroluminescence surface light emitting device according to claim 1.