JP5560359B2 - Organic light emitting diode and light source device using the same - Google Patents

Description

  The present invention relates to an organic light emitting diode and a light source device using the same.

  As a conventional example, Patent Document 1 discloses the following technique. An object of the prior art is to provide an organic electroluminescence device that efficiently extracts lost light confined as guided light inside the device and is excellent in external extraction efficiency. In the prior art, a pair of electrodes consisting of at least one organic layer including a light emitting layer and a reflective electrode and a transparent electrode sandwiching the organic layer is a front luminance value of emitted light emitted from the light extraction surface to the observer side. And the luminance value in the direction of 50 to 70 degrees satisfy the relationship of the front luminance value <the luminance value in the direction of 50 to 70 degrees, the emitted light is transmitted from the light emitting layer to the transparent electrode. The present invention relates to an organic electroluminescence element characterized in that a region in which the reflection / refraction angle of light is disturbed before being emitted to the observer side via a light source is provided.

JP 2004-296423 A

  There is a problem that light extraction efficiency is low because total reflection occurs at the interface of each layer constituting the organic light emitting diode. An object of the present invention is to improve light extraction efficiency in an organic light emitting diode and a light source device using the same.

  The features of the present invention for solving the above-described problems are as follows.

  An electrode, an organic layer having a light emitting point, a transparent electrode, a first transparent resin layer, a first conical transparent resin formed in the first transparent resin layer, an emission side substrate, a first Two conical transparent resins, and in the light extraction direction from the organic layer, the electrodes, the organic layer, the transparent electrode, the first transparent resin layer, the first conical transparent Resin, the emission-side substrate, and the second cone-shaped transparent resin are arranged in this order, and the bottom surfaces of the first cone-shaped transparent resin and the second cone-shaped transparent resin are bonded to the emission-side substrate, and the first One conical transparent resin has a spread from the first transparent resin layer to the output side substrate in the normal direction of the output side glass substrate, and the refractive index of the second conical transparent resin is The refractive index of the exit side substrate is the same, and the second conical transparent resin is the exit side. In the normal direction of the plate, the organic light emitting diode to the light extraction direction from the organic layer, characterized by having a spread towards the opposite direction.

  According to the present invention, an organic light emitting diode with improved light extraction efficiency and a light source device using the same can be provided. Problems, configurations, and effects other than those described above will be clarified by the following description of embodiments.

The perspective view which shows the structure of one Embodiment of this invention. Sectional drawing which shows the structure in one Embodiment of this invention. Sectional drawing for demonstrating the interference effect of an organic light emitting diode. The graph which shows the effect in one Embodiment of this invention. Sectional drawing which shows the principle in one Embodiment of this invention. Sectional drawing in one Embodiment of this invention, and the top view of a light-scattering layer. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The perspective view which shows the structure in one Embodiment of this invention. Sectional drawing which shows the principle in one Embodiment of this invention. Sectional drawing which shows the principle in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The top view which shows the structure in one Embodiment of this invention. The perspective view which shows the structure in one Embodiment of this invention. The perspective view which shows the structure in one Embodiment of this invention. The perspective view which shows the structure in one Embodiment of this invention. Sectional drawing which shows the structure in one Embodiment of this invention. Sectional drawing which shows the principle in one Embodiment of this invention. The graph which shows the effect in one Embodiment of this invention. The perspective view which shows the structure in one Embodiment of this invention. Sectional drawing which shows the structure in one Embodiment of this invention. Sectional drawing which shows the principle in one Embodiment of this invention. Conventional organic light emitting diode structure. Conventional organic light emitting diode structure.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The structure of the organic light emitting diode shown in FIG. 37 is as follows. An organic layer made of organic molecules is formed on the reflective electrode formed on the reflective substrate. On the organic layer, ITO (indium oxide with a small amount of tin added) or IZO (indium oxide with a small amount of zinc added) is formed as a transparent electrode. Further, a transparent resin layer is disposed on the transparent electrode, and an emission side substrate is disposed on the transparent resin. Such a configuration is generally called a top emission type. On the other hand, the structure of the organic light emitting diode shown in FIG. 38 is as follows. A transparent electrode is disposed on the emission side substrate. An organic layer is formed on the transparent electrode. A reflective electrode is formed on the organic layer. A sealing glass as a reflection side substrate is disposed on the reflective electrode through a layer filled with vacuum or an inert gas. Such a configuration is generally called a bottom emission type. Both the top emission type and the bottom emission type illuminate the outside by emitting light emitted from the organic layer from the emission side substrate.

  Aluminum is used for the reflective electrode. For example, when the reflective electrode is used as a cathode, a layer called an electron transport layer is formed on the reflective electrode, and a hole transport layer is formed on the transparent electrode side. A layer called a light-emitting layer is formed between the electron transport layer and the hole transport layer, and electrons and holes are generated in an area of about 10 nm near the interface between the light-emitting layer and the electron transport layer or near the interface between the light-emitting layer and the hole transport layer. Recombination occurs and the organic layer emits light. Whether the light emission mainly occurs at the interface between the hole transport layer side and the electron transport layer side of the light emitting layer is arbitrarily designed according to the mobility of the material. In the present invention, the interface where main light emission occurs as described above is called a light emission point.

  The refractive index of the organic layer is usually about 1.8, the refractive index of the transparent electrode is about 2.0, the refractive index of the transparent resin layer is about 1.5, and the refractive index of the emission side substrate is about 1.5. .

  Light emitted from the light emission point passes through the transparent electrode, the transparent resin layer, and the emission side substrate, and is emitted to the outside. However, in the case of the top emission type, reflection occurs at the interface between the transparent electrode and the transparent resin layer, the interface between the transparent resin layer and the emission side substrate, and the interface between the emission side substrate and the air. Is very low. In the case of the bottom emission type, reflection occurs at the interface between the transparent electrode and the emission side substrate and the interface between the emission side substrate and the air, so that the amount of light extracted to the outside is very low.

  Light that cannot be extracted to the output side substrate due to the influence of total reflection is called a thin film waveguide mode. The light emitted at the light emitting point is divided into light traveling toward the transparent electrode and light traveling once toward the transparent electrode after being reflected by the reflective electrode. In this case, if the interference condition between the two lights is not properly controlled, the thin film waveguide mode is increased.

  On the other hand, light that is totally reflected at the interface between the emission side substrate and air and cannot be extracted into the air is called a thick film waveguide mode. The light extracted into the air is referred to as an external extraction mode.

If the light emitted from the organic layer is 100%,
Thin film waveguide mode (%) = 100−Ejection efficiency to the emission side substrate Thick film waveguide mode (%) = Ejection efficiency to the emission side substrate−Ejection efficiency to air External extraction mode (%) = Extraction to air Efficiency = light extraction efficiency
Light extraction efficiency (%) = 100− (thin film waveguide mode + thick film waveguide mode)
There is a relationship.

  In order to increase the light extraction efficiency, it is necessary to reduce both the thin film waveguide mode and the thick film waveguide mode and increase the external extraction mode. The following examples have been made in view of the above problems, and in an organic light-emitting diode, a technique capable of obtaining high light extraction efficiency by reducing both the thin film waveguide mode and the thick film waveguide mode. Is to provide.

  The present invention will be described in more detail with reference to specific examples. The following examples show specific examples of the contents of the present invention, and the present invention is not limited to these examples, but by those skilled in the art within the scope of the technical idea disclosed in this specification. Various changes and modifications are possible. Further, in all the drawings for explaining the embodiments, the same reference numerals are given to those having the same function, and repeated explanation thereof is omitted.

  FIG. 1 is an exploded perspective view of the organic light emitting diode of the present embodiment. Moreover, FIG. 2 is a figure which shows the cross-sectional structure of the organic light emitting diode of this embodiment. The organic light emitting diode of this embodiment includes a reflective substrate 101, an aluminum reflective electrode 102, an organic layer 103, a transparent electrode 105 made of ITO or IZO, a first transparent resin layer 106, an output substrate 108, and a light scattering layer. 109. The direction in which light travels from the reflection side substrate 101 to the emission side substrate 108 is defined as a light extraction direction from the organic layer 103. Examples of the reflection side substrate 101 and the emission side substrate 108 include glass and plastic substrate materials (polychloropyrene, polyethylene terephthalate, etc.). From the viewpoint of preventing contamination of the organic layer, it is desirable that the reflection side substrate 101 and the emission side substrate 108 be made of glass. A reflective electrode 102 is formed on the reflective substrate 101. An organic layer 103 made of organic molecules is formed on the reflective electrode 102. The refractive index of the organic layer 103 is about 1.8, specifically 1.7 or more and 1.9 or less. The organic layer 103 includes a light emitting point 104. Blue light emission having a peak wavelength of 460 nm occurs from the light emission point 104. A transparent electrode 105 is formed on the organic layer 103. The refractive index of the transparent electrode 105 is about 2.0, specifically 1.95 or more and 2.05 or less. Further, the first transparent resin layer 106 is disposed on the transparent electrode 105. The reflective electrode 102 reflects the light emitted from the organic layer 103. Instead of the reflective electrode 102, a reflective plate having reflectivity and the transparent electrode 105 may be used. In this case, a reflection plate is formed on the reflection side substrate 101, and the transparent electrode 105 is formed on the reflection plate. An Ag substrate or the like can be considered as the reflecting plate.

  The first transparent resin layer 106 joins the transparent electrode 105 and the emission side substrate 108. The first transparent resin layer 106 uses an acrylic resin. The refractive index of the first transparent resin layer 106 can be controlled by dispersing the titanium oxide fine particles 110 using an acrylic resin as a base material. The refractive index of the first transparent resin layer 106 can be arbitrarily set from 1.5 to 2.2. Examples of the base material of the first transparent resin layer 106 include transparent resins having adhesive properties such as PET (polyethylene terephthalate), silicone-based, acrylic-based, polyimide, and epoxy. An emission side substrate 108 is disposed on the first transparent resin layer 106. The refractive index of the emission side substrate 108 is about 1.5, specifically, 1.50 or more and 1.56 or less. A light scattering layer 109 is disposed on the emission side substrate 108. As shown in FIG. 1, the light scattering layer 109 may not be formed on the entire surface of the emission side substrate 108. For example, productivity can be improved by making the area of the light scattering layer 109 smaller than the area of the emission side substrate 108 in the in-plane direction of the emission side substrate 108. In the light scattering layer 109, fine particles 110 of zircon oxide are dispersed using an acrylic resin as a base material. It is desirable that the substrate is transparent and has adhesiveness. Further, the refractive index of the base material of the light scattering layer 109 is preferably close to the refractive index of glass, and more preferably the same. “The same refractive index” means the same degree that the effect of the present embodiment can be achieved, and does not require strict coincidence. Specifically, the refractive index difference between the two may be within 0.1, and is preferably within 0.05. As a base material of the light scattering layer 109, epoxy resin, PET, or the like can be used in addition to acrylic resin. As the material of the fine particles 110, barium titanate, aluminum oxide, or the like can be used in addition to zircon oxide. One kind of the above materials may be included as the fine particles 110, or two or more kinds may be included. The refractive index of the acrylic resin is about 1.5, which is the same as the refractive index of the emission side substrate 108. The refractive index of each layer is measured at room temperature by, for example, an optical thin film measurement system FilmTek 3000 (manufactured by Yarman Co., Ltd.). The organic light emitting diode shown in FIG. 1 is provided with a drive device for driving the organic light emitting diode, thereby providing a light source device.

  In the configuration shown in FIG. 1, the refractive index of the transparent electrode 105 is larger than the refractive index of the first transparent resin layer 106. The refractive index of the first transparent resin layer 106 is the same as the refractive index of the emission side substrate 108. The refractive index of the emission side substrate 108 is higher than the refractive index of air. The refractive index of the fine particles 110 included in the light scattering layer 109 is higher than the refractive index of the base material included in the scattering layer and the emission side substrate 108.

  In addition, since the refractive index of the first transparent resin layer 106 is substantially equal to the refractive index of the emission side substrate 108, it is substantially the same as that having no optical interface between the first transparent resin layer 106 and the emission side substrate 108. . That is, the configuration shown in FIG. 1 is equivalent to a configuration in which the first transparent resin layer 106 is not provided and the transparent electrode 105 and the emission side substrate 108 are directly bonded.

  In FIG. 1, the light scattering layer 109 is disposed on the side opposite to the side where the transparent electrode 105 exists with respect to the emission side substrate 108, but the light scattering layer 109 is disposed between the emission side substrate 108 and the transparent electrode 105. You may arrange in. By disposing the light scattering layer 109 between the emission side substrate 108 and the transparent electrode 105, the light scattering layer 109 can be protected by the emission side substrate 108 which is resistant to deterioration.

  On the other hand, when the light scattering layer 109 is formed, irregularities may be formed on the surface of the light scattering layer 109. Therefore, by arranging the light scattering layer 109 on the side opposite to the side where the transparent electrode 105 exists with respect to the emission side substrate 108, the surface of the light scattering layer 109 where the unevenness is present becomes the emission side glass substrate 108. Productivity improves because it does not touch. In any case, the light scattering layer 109 is in contact with the emission side substrate 108.

  In the case of the bottom emission type, since the first transparent resin layer 106 shown in FIG. 1 is basically unnecessary, the number of members can be reduced. On the other hand, in the case of the top emission type, since the first transparent resin layer 106 is disposed between the emission side substrate 108 and the transparent electrode 105, a first conical transparent resin 107 to be described later can be provided, and a thinner film can be provided. The waveguide mode can be reduced. Even in the top emission type, when the emission side substrate 108 and the transparent electrode 105 are joined by the light scattering layer 109, the first transparent resin layer 106 is unnecessary. Further, the first transparent resin layer 106 may be provided even in a bottom emission type.

  As shown in FIG. 2, the distance from the interface between the reflective electrode 102 and the organic layer 103 to the center of the light emission point 104 is determined using a value 0 <a <1 and the film thickness d (nm) of the organic layer 103. Expressed with xd. That is, a = 0 at the interface between the reflective electrode 102 and the organic layer 103, and a = 1 at the interface between the organic layer 103 and the transparent electrode 105.

  Here, the interference condition will be described. FIG. 3 is a diagram for explaining the interference condition. The center of the light emitting point 104 is an arbitrary number of 0 <a <1, and occurs at a height a × d from the interface between the reflective electrode 102 and the organic layer 103. The point where the light emitting point 104 is located is a point light source. Assume that The arrows in the figure indicate the light propagation direction.

  The light emitted from the light source is directly directed to the transparent electrode 105 like the light indicated by A in FIG. 3, and the light directed to the transparent electrode 105 after being reflected by the reflective electrode 102 once as indicated by B. There is. The light distribution angle θ (°) at which the phase difference between the A light and the B light is an integer multiple of 2π due to the interference effect is the angle at which the light intensity is most enhanced. The light distribution angle is an angle representing the direction of light with the normal direction of the interface of each layer as an angle reference (0 °).

The most intense light distribution angle is expressed as θ cof (°).
θcof (°) = cos ⁻¹ ((2 × b−φm / 180) × λ / (4 × n × a × d)) × 180
/ Π (Formula 1)
It becomes. Here, b is an integer of 1 or more, λ is the wavelength of light (nm), n is the refractive index of the organic layer 103, d is the film thickness (nm) of the organic layer 103, a is a value of 0 <a <1, π is the circumference, and φm is a phase change due to reflection at the reflective electrode 102, and varies depending on the wavelength of light, the incident angle, the polarization direction, and the material of the reflective electrode 102. When the organic layer 103 is formed by stacking a light emitting layer, a hole transport layer, an electron transport layer, and the like, the average value of the refractive indexes of the layers constituting the organic layer 103 is set to n. When aluminum is used for the reflective electrode 102, the value of φm is about 140 ° to 160 ° until the incident angle is about 0 ° to 50 °. In this embodiment, for simplicity, φm is set to 155 ° as a representative value. From Equation 1, θ cof varies with a. That is, θ cof is controlled by the distance from the interface between the reflective electrode 102 and the organic layer 103 to the light emission point 104.

  Note that the light emission point 104 is a position where electrons and holes recombine in the organic layer 103 to emit light, and has a relatively high degree of freedom by setting the film thickness of a highly mobile organic material such as a hole transport layer. The setting in the state is possible. As a material for the hole transport layer, N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′diamine (TPD), 4,4 ′ -Bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) and the like. When the organic layer 103 includes a red light emitting layer, a green light emitting layer, and a blue light emitting layer, the thin film waveguide mode can be reduced if at least one light emitting point 104 satisfies Equation 1. However, the thin film waveguide mode can be further reduced by satisfying Equation 1 at all the light emitting points 104. Note that the film thickness can be reduced if it is not necessary to satisfy Equation 1 at all the light emission points 104.

  The amount of light extracted to the first transparent resin layer 106 can be controlled depending on which direction the light distribution angle is set to θcof. As described above, the setting of θ cof is called an interference condition setting.

  FIG. 4 is a graph showing the relationship between θcof (°) and extraction efficiency to the emission side substrate 108 and external extraction efficiency in the configuration of FIG. By setting θ cof to be not less than 35 ° and not more than 50 °, the extraction efficiency to the emission side substrate 108 can be improved. That is, it can be seen that the thin film waveguide mode can be reduced. Preferably, the thin film waveguide mode can be further reduced by setting θ cof to 41 ° or more and 46 ° or less. As described above, the thin film waveguide mode can be reduced by appropriately setting the interference condition. However, when θ cof is set to about 35 ° or more and 50 ° or less, the thin film waveguide mode can be reduced, but the thick film waveguide mode is increased and the external extraction efficiency is not improved. Therefore, in addition to reducing the thin film waveguide mode by setting θcof, it is necessary to reduce the thick film waveguide mode. The thick film waveguide mode reducing means in this embodiment will be described below.

  FIG. 5 is a diagram illustrating the principle of reducing the thick film waveguide mode by the light scattering layer 109. When there is no light scattering layer 109, as shown by the light path a in FIG. 5, light having an incident angle larger than the total reflection critical angle defined by the refractive index of the emission side substrate 108 and the refractive index of air. Is totally reflected at the interface between the emission-side substrate 108 and air. As a result, the thick film waveguide mode is large.

  Therefore, the fine particles 110 are dispersed in the light scattering layer 109. When light is incident on the fine particles 110, the light is separated and divided in various directions by scattering as indicated by the light path b. Therefore, since light having an incident angle smaller than the total reflection critical angle at the interface between the emission side substrate 108 and air is generated, the light can be extracted to the outside and the thick film waveguide mode can be reduced.

  In order to efficiently extract light to the outside by light scattering by the light scattering layer 109, it is necessary to select a suitable particle size of the fine particles 110 (diameter of the fine particles 110) and arrangement density of the fine particles 110. Therefore, as shown in FIG. 6, when the organic layer 103 has a thickness of 150 nm, the emission point 104 has a height of 98 nm from the reflective electrode 102, and the refractive index of the first transparent resin layer 106 is 1.5, the particle size of the fine particles 110 is small. The relationship between the average particle pitch and the thick film waveguide mode was simulated. Here, the fine particle pitch is a distance in the surface direction between adjacent fine particles 110 as shown in FIG. The fine particle average pitch is an average value of the fine particle pitch of all the fine particles 110 within 20 μm square where the light scattering layer 109 is provided. The height 98 nm of the light emitting point 104 from the reflective electrode 102 is a value when θ cof is set to 42 °. When the light scattering layer 109 includes particles having different particle diameters, the particle diameter of the fine particles 110 may be considered as the average particle diameter.

  7 and 8 show simulation results when the refractive index of the fine particles 110 is 2.4 and 1.8. In addition, the thick film waveguide mode in the case where the light scattering layer 109 is not shown is shown with an average fine particle pitch of 0 μm for convenience. Further, the amount of light of an organic light-emitting diode produced by using as the fine particles 110 of the light scattering layer 109, fine particles 110 of zircon oxide having a refractive index of 2.4, a particle size of 0.57 μm and a particle size of 1.0 μm and a refractive index of 2.4 The thick film waveguide mode estimated from the measurement is also shown in the figure.

  As shown in FIG. 7, when the refractive index of the fine particles is 2.4, the thick film waveguide has a fine particle diameter in the range of 0.5 μm to 6.0 μm and the average fine particle pitch is in the range of 0.5 μm to 12 μm. The mode has been reduced. More preferably, the thick film waveguide mode is further reduced in the range where the particle size is 0.5 μm or more and 4.0 μm or less and the average particle pitch is 0.5 μm or more and 7.0 μm or less.

  More specifically, there is a fine particle average pitch suitable for each particle size.

  When the particle size of the fine particles 110 is 0.5 μm, the fine particle average pitch is preferably 0.5 μm or more and 3.0 μm or less, and the optimum value of the fine particle average pitch is 1.0 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 6.0 times the particle size of the fine particles 110, and particularly preferably 2.0 times. .

  When the particle size of the fine particles 110 is 1 μm, the fine particle average pitch is preferably 1.0 μm or more and 3.5 μm or less, and the optimum value of the fine particle average pitch is 3.0 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 3.5 times the particle size of the fine particles 110, and particularly preferably 3.0 times. .

  When the particle diameter of the fine particles 110 is 2 μm, the fine particle average pitch is preferably 2.0 μm or more and 4.75 μm or less, and the optimum value of the fine particle average pitch is 4.0 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 2.4 times the particle size of the fine particles 110, and particularly preferably 2.0 times. .

  When the particle size of the fine particles 110 is 4 μm, the fine particle average pitch is preferably 4.0 μm or more and 7.0 μm or less, and the optimum value of the fine particle average pitch is 6 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 1.8 times the particle size of the fine particles 110, and particularly preferably 1.50 times. .

  As shown in FIG. 8, when the refractive index of the fine particles 110 is 1.8, the thick film is introduced in the range where the fine particle diameter is 0.5 μm or more and 6.0 μm or less and the average fine particle pitch is 0.5 μm or more and 12 μm or less. Wave mode has been reduced. More preferably, the thick film waveguide mode is further reduced when the particle size is 0.5 μm or more and 2.0 μm or less and the average particle pitch is 0.5 μm or more and 4.0 μm or less.

  More specifically, there is a fine particle average pitch suitable for each particle size.

  When the particle diameter of the fine particles 110 is 0.5 μm, the fine particle average pitch is preferably 0.5 μm or more and 2.75 μm or less, and the optimum value of the fine particle average pitch is 1.50 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 5.5 times the particle size of the fine particles 110, and particularly preferably 3.0 times. .

  When the particle size of the fine particles 110 is 1 μm, the fine particle average pitch is preferably 1.0 μm or more and 3.25 μm or less, and the optimum value of the fine particle average pitch is 1.5 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 3.3 times the particle size of the fine particles 110, and particularly preferably 1.5 times. .

  When the particle size of the fine particles 110 is 2 μm, the fine particle average pitch is preferably 2.0 μm or more and 4.0 μm or less, and the optimum value of the fine particle average pitch is 2.0 μm. Regarding the relationship between the particle size of the fine particles 110 and the fine particle average pitch, the fine particle average pitch is preferably 1.0 to 2.0 times the particle size of the fine particles 110, and particularly preferably 1.0 times. .

  As described above, when the fine particles 110 having a particle size of 0.5 μm or more and 6.0 μm or less are used as the specific fine particles, if the average fine particle pitch of the specific fine particles is 1.0 to 6.0 times the particle size of the specific fine particles. The thick film waveguide mode can be reduced. Further, when the average fine particle pitch of the specific fine particles is not less than the particle size of the specific fine particles and not more than 12 μm, the thick film waveguide mode can be reduced.

  More preferably, when the fine particles 110 having a particle size of 0.5 μm or more and 2.0 μm or less are used as special fine particles, the average fine particle pitch of the special fine particles may be 1.0 to 3.0 times the particle size of the special fine particles. Thus, the thick film waveguide mode can be further reduced. Further, if the average fine particle pitch of the special fine particles is not less than the particle size of the special fine particles and not more than 4.0 μm, the thick film waveguide mode can be further reduced.

  As long as the effect of the present embodiment can be achieved, the fine particles 110 may include the fine particles 110 having a particle size smaller than 0.5 μm, or the fine particles 110 having a particle size larger than 6.0 μm. It may be.

  As described above, the thin film waveguide mode can be reduced by appropriately setting the light emission point 104. In addition, the thick film waveguide mode can be reduced by appropriately setting the particle size and arrangement density of the fine particles 110 of the light scattering layer 109. As described above, high light extraction efficiency can be obtained.

  Further, the thin film waveguide mode can be further reduced by adopting the following configuration. A configuration capable of reducing the thin film waveguide mode is shown in an exploded perspective view of FIG. 9 and a cross-sectional view of FIG. A first conical transparent resin 107 having a bottom surface bonded to the surface of the emission side substrate 108 is embedded in the first transparent resin layer 106. The refractive index of the first conical transparent resin 107 can be arbitrarily set from 1.4 to 1.8. In the normal direction of the emission side substrate 108, the first conical transparent resin 107 has a spread from the first transparent resin layer 106 toward the emission side substrate 108. In this embodiment, the spread angle of the first conical transparent resin 107 in the direction of the emission side substrate 108 is expressed as θ pri as shown in FIG. The refractive index of the first conical transparent resin 107 is expressed as npri, and the refractive index of the transparent resin is expressed as nLPL.

  FIG. 11 is a principle diagram for reducing the thin film waveguide mode in the present embodiment. By disposing the first conical transparent resin 107 in the first transparent resin layer 106, the thin film waveguide mode can be reduced. The refractive index of the first conical transparent resin 107 is smaller than the refractive index of the first transparent resin layer 106 and is equal to or higher than the refractive index of the emission side substrate 108. In the case where there is no conical first conical transparent resin 107 as in the light path indicated by a in FIG. 11, total reflection was performed at the interface between the first transparent resin layer 106 and the emission side substrate 108. Therefore, by inserting the first conical transparent resin 107, a light beam path indicated by b in FIG. 11 is formed. That is, since the incident angle from the first transparent resin layer 106 to the first conical transparent resin 107 is smaller than the incident angle from the first transparent resin layer 106 to the emission side substrate 108 indicated by a, total reflection is performed. Without being emitted to the emission-side substrate 108. Thereby, a thin film waveguide mode can be reduced. In addition, the light path b in FIG. 11 shows an example in which the refractive index of the first conical transparent resin 107 and the refractive index of the emission side substrate 108 are the same. However, there is a case where the light traveling in the normal direction is totally reflected at the interface between the conical first conical transparent resin 107 and the first transparent resin layer 106 like a light beam indicated by c in FIG. is there. Further, when the refractive index of the first conical transparent resin 107 is higher than the refractive index of the emission side substrate 108, it is totally reflected at the interface between the conical first cone shape transparent resin 107 and the emission side substrate 108. May end up. Therefore, it is necessary to optimize the following parameters in order to minimize the thin film waveguide mode.

Parameters that need to be optimized nLPL
・ Npri
・ Θpri
・ Θcof
The parameter optimization is described below.

  FIG. 12 shows various wavelengths with a wavelength of 460 nm, a film thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.6, and a refractive index of the conical first conical transparent resin 107 of 1.5. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions. The thin film waveguide mode in the case of θpri = 90 ° corresponds to a value when the first conical transparent resin 107 is not used, and a region having a value lower than this is due to the first conical transparent resin 107. It is effective in reducing the thin film waveguide mode.

  The relative value of the thin film waveguide mode shows strong dependence on θcof and θpri, and θcof is a low value when it is about 36 ° to 48 °, and θpri is about 80 ° to 87 °. θcof = 42 ° and θpri = 85 ° are the lowest values.

  Note that the distance a × d to the center of the light emission point 104 corresponding to θ cof from 36 ° to 48 ° from Equation 1 is (2-155 / 180) λ / 4 / n / cos 36 ° ≦ a × d ≦ ( 2-155 / 180) λ / 4 / n / cos of 48 °, which is not less than 90 nm and not more than 109 nm.

  FIG. 13 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.7, and a refractive index of the first conical transparent resin 107 of 1.5. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 75 ° or more and 85 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 82 °.

  FIG. 14 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.7, and a refractive index of the first conical transparent resin 107 of 1.6. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 71 °.

  FIG. 15 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.8, and a refractive index of the first conical transparent resin 107 of 1.5. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 75 ° or more and 85 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 82 °.

  FIG. 16 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.8, and a refractive index of the first conical transparent resin 107 of 1.6. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 74 °.

  FIG. 17 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.8, and a refractive index of the first conical transparent resin 107 of 1.7. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 62 ° or more and 80 ° or less, and is preferably the lowest value when θ cof = 42 ° and θ pri = 71 °.

  FIG. 18 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.9, and a refractive index of the first conical transparent resin 107 of 1.5. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 75 ° or more and 85 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 83 °.

  FIG. 19 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.9, and a refractive index of the first conical transparent resin 107 of 1.6. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 76 °.

  FIG. 20 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 1.9, and a refractive index of the first conical transparent resin 107 of 1.7. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 63 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 74 °.

  FIG. 21 shows the light wavelength of 460 nm, the thickness of the organic layer 103 of 150 nm, the refractive index of the first transparent resin layer 106 of 1.9, and the refractive index of the first conical transparent resin 107 of 1.8. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 57 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 74 °.

  FIG. 22 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 2.0, and a refractive index of the first conical transparent resin 107 of 1.5. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 75 ° or more and 85 ° or less, and is preferably the lowest value when θ cof = 42 and θ pri = 82 °.

  FIG. 23 shows a light wavelength of 460 nm, a film thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 2.0, and a refractive index of the first conical transparent resin 107 of 1.6. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 80 ° or less, and preferably has the lowest value when θ cof = 48 ° and θ pri = 75 °.

  In FIG. 24, the wavelength of light is 460 nm, the film thickness of the organic layer 103 is 150 nm, the refractive index of the first transparent resin layer 106 is 2.0, and the refractive index of the first conical transparent resin 107 is 1.7. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 85 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 78 °.

  FIG. 25 shows a light wavelength of 460 nm, a thickness of the organic layer 103 of 150 nm, a refractive index of the first transparent resin layer 106 of 2.0, and a refractive index of the first conical transparent resin 107 of 1.8. It is the result of having performed the simulation about the relationship between (theta) pri and the relative value of a thin film waveguide mode under interference conditions.

  The thin film waveguide mode has a low value when θ cof is 36 ° to 48 ° and θ pri is about 70 ° or more and 85 ° or less, and preferably has the lowest value when θ cof = 42 ° and θ pri = 78 °.

  The vertical axes of the graphs in FIGS. 12 to 25 are all in the same range.

  Next, the relationship of the refractive index that minimizes the thin film waveguide mode will be described.

  FIG. 26 shows each refractive index npri (1.4, 1.5, 1.5) of the first conical transparent resin 107 when θ cof and θ pri are optimized (the thin film waveguide mode is set to a minimum value). 1.6, 1.7, and 1.8) are parameters, the vertical axis represents the thin film waveguide mode, and the horizontal axis represents the refractive index nLPL of the first transparent resin layer 106.

  In order to further reduce the thin film waveguide mode, the refractive index nLPL of the first transparent resin layer 106 is preferably set to 1.7 or more and 2.0 or less. The refractive index of the first conical transparent resin 107 is preferably 1.5 or more and less than 1.7.

  The relationship between the refractive index and the thin film waveguide mode is related to the respective refractive index ratios of the first transparent resin layer 106, the first conical transparent resin 107, and the emission side substrate 108. For example, the higher the refractive index of the first cone-shaped transparent resin 107, the easier the light enters the first cone-shaped transparent resin 107 from the first transparent resin layer 106, but conversely the first cone-shaped transparent resin 107. It becomes difficult to enter the exit side substrate 108 from the top. Therefore, when the refractive index of the first transparent resin layer 106 is represented by nLPL and the refractive index of the output side substrate 108 is expressed by nglass, the refractive index ratio of the first transparent resin layer 106 to the refractive index of the output side substrate 108 nLPL / nglas. Is preferably 1.13 or more and 1.33 or less. The refractive index ratio npri / nglass of the first conical transparent resin 107 with respect to the refractive index of the emission side substrate 108 is preferably 1 or more and less than 1.13.

  Although the refractive index has been described discretely with a resolution of 0.1, the refractive index of the actual member is a continuous value. The value rounded to the nearest unit. Even if the refractive index is rounded off, there is almost no change in the preferable constituent elements such as the angle range of θpri for reducing the thin film waveguide mode described so far.

  As described above, by inserting the first conical transparent resin 107 and appropriately controlling the relationship between the refractive index of the first transparent resin layer 106 and the refractive index of the first conical transparent resin 107, Thin film waveguide mode can be reduced. Further, the thin film waveguide mode can be reduced by appropriately controlling the apex angle of the first conical transparent resin 107 and the position of the light emitting point 104 in the organic layer 103.

  FIG. 27 is a plan view of the surface on the emission side substrate 108 side of the first transparent resin layer 106. As shown in FIG. 27, the first conical transparent resin 107 was arranged in a finely packed manner. Thereby, the clearance gap between the 1st cone-shaped transparent resin 107 becomes small, and can reduce a thin film waveguide mode more.

  The first conical transparent resin 107 is not limited to the conical shape as shown in FIG. 9, but may be a quadrangular pyramid shape as shown in FIG. 28 or a hexagonal pyramid shape as shown in FIG. However, the shape of the first conical transparent resin 107 is preferably a conical shape. This is because the thin film waveguide mode can be reduced over all in-plane directions of the organic light emitting diode.

  As shown in this embodiment, the thick film waveguide mode can be reduced by appropriately setting the particle size and arrangement density of the fine particles 110 of the light scattering layer 109. In addition to the appropriate setting of the light emitting point 104 or the appropriate setting of the light emitting point 104, the refractive index setting of the first transparent resin layer 106, the refractive index setting of the first conical transparent resin 107, and the spread angle are set. The thin film waveguide mode can be reduced by appropriately performing the setting. As described above, the organic light emitting diode of this embodiment can obtain high light extraction efficiency. In addition, the above configuration promotes color mixing when light emitting layers having different colors are stacked.

  Another embodiment of the present invention will be described in detail.

  FIG. 30 is an exploded perspective view of the organic light emitting diode of the present embodiment. FIG. 31 is a diagram showing a cross-sectional configuration of the organic light emitting diode of the present embodiment. The organic light emitting diode of the present embodiment includes a reflective substrate 101, an aluminum reflective electrode 102, an organic layer 103, a transparent electrode 105, a first transparent resin layer 106, a first conical transparent resin 107, an output substrate 108, and a first substrate. Two conical transparent resins 111 are provided. 30 and 31 are explanatory diagrams of the top emission type, but a bottom emission type may also be used. An organic layer 103 made of organic molecules is formed on the aluminum reflective electrode 102 formed on the reflective substrate 101. The organic layer 103 includes a light emitting point 104. Blue light emission having a peak wavelength of 460 nm occurs from the light emission point 104. A transparent electrode 105 is formed on the organic layer 103. Further, the first transparent resin layer 106 is disposed on the transparent electrode 105. The first transparent resin layer 106 is embedded with a first conical transparent resin 107 having a bottom surface bonded to the surface of the emission side substrate 108. The refractive index of the conical first conical transparent resin 107 is about 1.5. An emission side substrate 108 is disposed on the first transparent resin layer 106. In the normal direction of the emission side substrate 108, the first conical transparent resin 107 has a spread from the first transparent resin layer 106 toward the emission side substrate 108. A second conical transparent resin 111 is provided on the emission side substrate 108. In FIG. 30, a plurality of conical resins are arranged on a rectangular parallelepiped resin to form the second conical transparent resin 111, but a rectangular parallelepiped resin is not necessarily required. However, by producing a flat resin such as a rectangular parallelepiped resin, the second conical transparent resin 111 can be molded by pressing a conical resin mold against the flat resin. The bottom surface of the second conical transparent resin 111 is bonded to the air side surface of the emission side substrate 108. The second conical transparent resin 111 is produced by molding an acrylic resin. The refractive index of the acrylic resin is about 1.5, which is the same as the refractive index of the emission side substrate 108. In the normal direction of the emission side substrate 108, the second conical transparent resin 111 spreads from air toward the emission side substrate 108 (the direction opposite to the light extraction direction from the organic layer 103). In the present specification, the spread angle of the second conical transparent resin 111 in the direction of the emission side substrate 108 is denoted as θpri2 as shown in FIG.

  The technique for reducing the thin film waveguide mode of this embodiment is the same as that shown in the first embodiment.

  FIG. 32 is a principle diagram of reduction of the thick film waveguide mode according to the present embodiment. When the second conical transparent resin 111 is not present, light having an incident angle larger than the total reflection critical angle at the interface between the emission side substrate 108 and air is emitted as shown by a light ray path a in FIG. Total reflection occurs at the interface between the side substrate 108 and air. As a result, the thick film waveguide mode is large. When light is incident on the second cone-shaped transparent resin 111, the incident angle is reduced due to the inclination of the second cone-shaped transparent resin 111 as shown by the light path b, so that the light can be extracted to the outside, and the thick film waveguide mode Can be reduced.

  FIG. 33 is a graph showing the effect of reducing the thick film waveguide mode according to this example. Assuming that θcof = 42 ° and the refractive index of the first conical transparent resin 107 is 1.5, the refractive index nLPL of the first transparent resin layer 106 and θpri1 of the first conical transparent resin 107 are used as parameters. 33, the vertical axis represents the thick film waveguide mode, and the horizontal axis represents θpri2 (°). The refractive index nLPL of the first transparent resin layer 106 is 1.6, 1.7, 1.8, 1.9, 2.0, and θpri1 of the first conical transparent resin 107 is 80 °, respectively. They are 80 °, 75 °, 79 °, and 76 °.

  The thin film waveguide mode in the case of θpri2 = 90 ° corresponds to a value when the second cone-shaped transparent resin 111 is not used, and a region having a value lower than this is due to the second cone-shaped transparent resin 111. It is effective in reducing the thin film waveguide mode. More preferably, it is understood that it is preferable that θpri2 is about 45 ° or more and 60 ° or less.

  The second conical transparent resin 111 may have a conical shape, a quadrangular pyramid shape, or a hexagonal pyramid shape. Moreover, the efficiency can be improved by densely packing the same as the reason described for the arrangement of the first transparent resin layer 106 in the first embodiment.

  Another embodiment of the present invention will be described in detail.

  FIG. 34 is an exploded perspective view of the organic light emitting diode of the present embodiment. FIG. 35 is a diagram showing a cross-sectional configuration of the organic light emitting diode of the present embodiment. The organic light emitting diode of this embodiment includes a reflective substrate 101, an aluminum reflective electrode 102, an organic layer 103, a transparent electrode 105, a first transparent resin layer 106, a diffuse reflective layer 112, a second transparent resin layer 113, and an emission side. A substrate 108 is included. 34 and 35 are explanatory diagrams of the top emission type, but a bottom emission type may also be used. An organic layer 103 made of organic molecules is formed on the aluminum reflective electrode 102 formed on the reflective substrate 101. The organic layer 103 includes a light emitting point 104. A transparent electrode 105 is formed on the organic layer 103. Further, the first transparent resin layer 106 is disposed on the transparent electrode 105. The diffuse reflection layer 112 is bonded by the first transparent resin layer 106.

  In the diffuse reflection layer 112, a region where the reflective electrode 102 and the transparent electrode 105 overlap is opened in the normal direction of the diffuse reflection layer 112. That is, if one of the reflective electrode 102 and the transparent electrode 105 is solid and the other is striped, the opening of the diffuse reflection layer 112 is striped. Moreover, when both the reflective electrode 102 and the transparent electrode 105 are stripe-shaped and the extending direction of both is orthogonal, the opening part of the diffuse reflection layer 112 becomes dot shape like FIG. The opening of the diffuse reflection layer 112 is preferably dot-shaped. Further, the opening of the diffuse reflection layer 112 is preferably larger than the region where the reflective electrode 102 and the transparent electrode 105 overlap. This is because light having a large light distribution angle can be incident on the emission-side substrate 108.

  The diffuse reflection layer 112 uses a white sheet having a high reflectance. As the white sheet, for example, a PET film containing many fine bubbles by firing can be used. Specifically, a foaming polyester film manufactured by Toray Industries, Inc., Lumirror E60L, E6SL, E60V, or the like can be used. The material of the white sheet is not limited to this. For example, a plasticizer such as dibutyl phthalate is added to an acrylic resin having 4 or more carbon atoms in the side chain, or an acrylic resin having 1 to 3 carbon atoms in the side chain. Examples of the additive include white resin / powder mixture containing white powder such as magnesium oxide, titanium oxide, barium titanate and the like. Further, a white rubber / powder mixture in which a white powder such as magnesium oxide, titanium oxide, or barium titanate is contained in chloroprene rubber, silicone rubber, or fluorine-based rubber may be used. Further, it may be a metal reflective film having fine irregularities on the surface as used as the diffuse reflection layer 112 of the reflective liquid crystal display device. In this case, the surface on the emission side substrate 108 side of the second transparent resin layer 113 may be formed into a concavo-convex shape, and a metal such as aluminum or silver having a high reflectance may be formed thereon by a sputtering method. The second transparent resin layer 113 covers the diffuse reflection layer 112, and the second transparent resin layer 113 is included in the opening of the diffuse reflection layer 112. The emission side substrate 108 is bonded by the second transparent resin layer 113. The second transparent resin layer 113 uses the same acrylic resin as the first transparent resin layer 106. The second transparent resin layer 113 may not be the same as the first transparent resin layer 106. However, by making the material of the second transparent resin layer 113 the same as the material of the first transparent resin layer 106, the refractive index of both becomes the same, and the first transparent resin layer 106 and the second transparent resin The interface of the layer 113 is optically continuous. That is, it is optically equivalent to the case where the interface between the first transparent resin layer 106 and the second transparent resin layer 113 does not exist.

  FIG. 36 is a principle diagram for reducing the thick film waveguide mode in this embodiment. The light totally reflected at the interface between the emission side substrate 108 and air is diffusely reflected by the diffuse reflection layer 112. Since the incident angle of the part of the light diffusely reflected by the diffuse reflection layer 112 at the emission side substrate 108 and the air interface is smaller than the total reflection critical angle, it is extracted to the air side. In the absence of the diffuse reflection layer 112, the light is repeatedly totally reflected at the same incident angle to some extent at the interface between the emission side substrate 108 and the air and the reflection electrode 102, so that it is difficult to extract the light to the air side.

  Reduction of the thin film waveguide mode in the present embodiment is performed by appropriately setting the interference condition. As shown in FIG. 4 of the first embodiment, the thin film waveguide mode can be reduced by setting θ cof to about 35 ° to 50 °.

  Further, as a more preferable configuration, the first conical transparent resin 107 shown in Example 1 may be embedded in the first transparent resin layer 106. In this case, the same configuration as that described in the first embodiment is applied to the refractive index of the first transparent resin layer 106 and the preferable relationship between θcof, θpri, and the refractive index of the first conical transparent resin 107. it can. However, in this embodiment, the bottom surface of the first conical transparent resin 107 is bonded to the second transparent resin layer 113 with the diffuse reflection layer 112.

  The thin film waveguide mode reduction method and the thick film waveguide mode reduction method described in this specification can be combined in various ways.

DESCRIPTION OF SYMBOLS 101 Reflective side substrate 102 Reflective electrode 103 Organic layer 104 Light emitting point 105 Transparent electrode 106 First transparent resin layer 107 First conical transparent resin 108 Outgoing side substrate 109 Light scattering layer 110 Fine particle 111 Second conical transparent resin 112 Diffuse reflection layer 113 Second transparent resin layer

Claims (12)

Electrodes,
An organic layer having a light emitting point;
A transparent electrode;
A first transparent resin layer;
A first conical transparent resin formed in the first transparent resin layer;
An emission side substrate;
A second conical transparent resin,
In the direction of light extraction from the organic layer, the electrode, the organic layer, the transparent electrode, the first transparent resin layer, the first conical transparent resin, the emission side substrate, and the second cone Arranged in the order of transparent resin,
The bottom surfaces of the first conical transparent resin and the second conical transparent resin are bonded to the emission side substrate,
The first conical transparent resin has a spread from the first transparent resin layer to the emission side substrate in the normal direction of the emission side glass substrate,
The transparent electrode has a refractive index of 1.95 or more and 2.05 or less,
The refractive index of the first transparent resin layer is 1.7 or more and 2.0 or less,
The refractive index of the first conical transparent resin is 1.5 or more and less than 1.7,
The exit side substrate has a refractive index of 1.50 or more and 1.56 or less,
The refractive index of the first conical transparent resin is higher than the refractive index of the emission side substrate,
The refractive index of the second conical transparent resin is the same as the refractive index of the emission side substrate,
The organic light-emitting diode, wherein the second conical transparent resin has a spread in a direction opposite to a light extraction direction from the organic layer in a normal direction of the emission side substrate. In Claim 1, The said light emission point light-emits by light emission peak wavelength (lambda) (nm),
When the height from the interface between the electrode and the organic layer to the light emitting point is a × d (where d (nm) is the thickness of the organic layer, 0 <a <1), (2m−155 / 180) λ / 4 / n / cos 35 ° ≦ a × d ≦ (2m-155 / 180) λ / 4 / n / cos50 ° (where n is the refractive index of the organic layer and m is an integer of 1 or more) An organic light emitting diode characterized by the above. In Claim 1, The said light emission point light-emits by light emission peak wavelength (lambda) (nm),
When the height from the interface between the electrode and the organic layer to the light emitting point is a × d (where d (nm) is the thickness of the organic layer, 0 <a <1), (2m−155 / 180) λ / 4 / n / cos 36 ° ≦ a × d ≦ (2m-155 / 180) λ / 4 / n / cos 48 ° (where n is the refractive index of the organic layer and m is an integer of 1 or more) An organic light emitting diode characterized by the above. In Claim 1, The said light emission point light-emits by light emission peak wavelength (lambda) (nm),
When the height from the interface between the electrode and the organic layer to the light emitting point is a × d (where d (nm) is the thickness of the organic layer, 0 <a <1), (2m−155 / 180) λ / 4 / n / cos 41 ° ≦ a × d ≦ (2m-155 / 180) λ / 4 / n / cos 46 ° (where n is the refractive index of the organic layer and m is an integer of 1 or more) An organic light emitting diode characterized by the above. In any one of Claims 1 thru | or 4,
An organic light emitting diode, wherein the organic layer has a refractive index of 1.7 to 1.9 . In any one of Claims 1 thru | or 5,
The refractive index of the first transparent resin layer / the refractive index of the emission side substrate is 1.13 or more and 1.33 or less,
The organic light emitting diode, wherein a refractive index of the first conical transparent resin / a refractive index of the emission side substrate is 1 or more and less than 1.13. In any one of Claims 1 thru | or 6.
The refractive index of the first conical transparent resin is 1.50 or more and 1.54 or less,
An organic light-emitting diode, wherein a spread angle of the first conical transparent resin is 75 ° to 85 °. In any one of Claims 1 thru | or 6.
The refractive index of the first conical transparent resin is 1.55 or more and 1.64 or less,
An organic light-emitting diode, wherein a spread angle of the first conical transparent resin is 70 ° or more and 80 ° or less. In any one of Claims 1 thru | or 8.
The organic light-emitting diode, characterized in that the first conical transparent resin is closely packed with respect to the emission-side substrate surface. In any one of Claims 1 thru | or 9,
An organic light emitting diode, wherein a spread angle in a direction opposite to a light extraction direction from the organic layer in the second conical transparent resin is 45 ° or more and 60 ° or less. In any one of Claims 1 thru | or 10.
2. The organic light emitting diode according to claim 1, wherein the second conical transparent resin is closely packed with respect to the emission side substrate surface. An organic light emitting diode according to any one of claims 1 to 11,
And a driving device for driving the organic light emitting diode.

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