Light emitting device, display unit, photoelectric conversion device, and electronic equipment

Abstract

To provide technique that is advantageous in improving extraction efficiency of light in an oblique direction.SOLUTION: A light emitting device has a substrate, a light emission part which has a reflection layer, an organic layer and a conductive layer, and a lens which is arranged overlapping with at least a part of the light emission part in plan view of the substrate, and the lens has positive power, and is convex in the opposite direction from the substrate, wherein the vertex of the lens is not in the center of the light emission part in the plan view, and the reflection layer is inclined to a principal surface in cross section. A straight line passing the vertex of the lens and perpendicular to a straight line passing both ends of the lens and a normal of the reflection layer at a first position of the inclined part cross each other at one point, the first position being the point at the largest distance from the vertex of the lens in a direction parallel with the principal surface in the inclined part of the reflection layer. Here, the one point is located at the vertex of the lens, or more on a light extraction side than the vertex.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a light-emitting device, a display device, a photoelectric conversion device, and an electronic device. [Background technology]

[0002] To improve the performance of a light-emitting device, it may be necessary to increase the light extraction efficiency not only in the front direction but also in oblique directions. In particular, when a light-emitting display is used as a display device such as a head-mounted display, it may be used in combination with an optical system such as a pancake lens. In this case, light emitted in an oblique direction is mainly used in the peripheral part of the display area, and it may be necessary to increase the light extraction efficiency in the oblique direction to improve the display quality in the peripheral part of the display area.

[0003] Furthermore, when a light-emitting device is used as an exposure device for a photosensitive body, it may be used in combination with an optical system such as a SELFOC (registered trademark) lens. When multiple light-emitting units are arranged in a staggered pattern, for example, and the light-emitting units and the center of the optical system are displaced from each other, it may be necessary to improve the light extraction efficiency in the diagonal direction from the light-emitting units toward the center of the optical system in order to improve light utilization efficiency.

[0004] In order to improve the efficiency of extracting light in an oblique direction in an organic light-emitting device, Patent Document 1 discloses that in a light-emitting element having an on-chip microlens that diverges light from an organic layer, the on-chip microlens and the light-emitting section are formed so as to be offset from each other. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2019-133816 Summary of the Invention [Problem to be solved by the invention]

[0006] By extracting the light emitted from the light-emitting portion more efficiently in an oblique direction, the performance of the light-emitting device can be further improved.

[0007] One aspect of the present invention provides a technique that is advantageous for improving light extraction efficiency in oblique directions. [Means for solving the problem]

[0008] a substrate; a first light-emitting section having a reflective layer disposed on a main surface of the substrate, an organic layer disposed on the reflective layer, and a conductive layer disposed on the organic layer; and a first lens disposed so as to overlap at least a part of the first light-emitting section in a plan view from a direction perpendicular to the main surface of the substrate, wherein the first lens has positive power and has a convex shape in a direction opposite to the substrate, and in a cross section passing through an apex of the convex shape of the first lens and perpendicular to the main surface, the apex of the first lens is located at the center of the first light-emitting section, and The light-emitting device is a light-emitting device that is a first distance away from the center, and in the cross section, the reflective layer has an inclined portion inclined with respect to the main surface, and the first position is a point on the inclined portion of the reflective layer that is farthest from the vertex of the first lens in a direction parallel to the main surface, and a second line that extends in a direction perpendicular to a first line passing through both ends of the first lens and passes through the vertex of the first lens intersects with a normal to the reflective layer at the first position of the inclined portion at one point, and the one point coincides with the vertex of the first lens or is located closer to the light extraction side than the vertex of the first lens. [Effects of the Invention]

[0009] According to one aspect of the present disclosure, it is possible to provide a technique that is advantageous for improving the light extraction efficiency in oblique directions. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a diagram showing a configuration example of a light emitting device according to an embodiment of the present invention; [Figure 2]FIG. 10 is a diagram showing a configuration example of a light emitting device of a comparative example. [Figure 3] 6 is a graph for explaining the present embodiment and a comparative example. [Figure 4] FIG. 10 is a diagram showing a configuration example of a light emitting device of a comparative example. [Figure 5] 1 is a diagram showing a configuration example of a light emitting device according to an embodiment of the present invention; [Figure 6] 1 is a diagram showing a configuration example of a light emitting device according to an embodiment of the present invention; [Figure 7] 1 is a diagram showing a configuration example of a light emitting device according to an embodiment of the present invention; [Figure 8] 3A and 3B are diagrams showing examples of the configuration of a reflective layer of the light emitting device of the present embodiment. [Figure 9] 3A and 3B are diagrams showing examples of arrangement of light emitting elements in the light emitting device of the present embodiment. [Figure 10] 1A and 1B are diagrams illustrating an example of a display device using the light-emitting device of this embodiment. [Figure 11] FIG. 1 is a diagram showing an example of a photoelectric conversion device using the light emitting device of this embodiment. [Figure 12] 1A to 1C are diagrams illustrating examples of electronic devices using the light-emitting device of this embodiment. [Figure 13] 1A and 1B are diagrams illustrating an example of a display device using the light-emitting device of this embodiment. [Figure 14] 1 is a diagram showing an example of a lighting device using the light-emitting device of this embodiment. [Figure 15] 1A and 1B are diagrams showing an example of a moving object using the light emitting device of the present embodiment. [Figure 16] FIG. 1 is a diagram showing an example of a wearable device using the light-emitting device of the present embodiment. [Figure 17] 1 illustrates an image forming apparatus according to the present embodiment. [Figure 18] 8(a) is a schematic diagram showing the planar shape in the configuration example of Fig. 8(d), and Figs. 8(b) to 8(d) are schematic diagrams showing the planar shapes of the reflective layer, the light-emitting portion, and the inclined portion in another configuration example of the light-emitting device of this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0012] Light emitting devices according to embodiments of the present disclosure will be described with reference to Figures 1 to 9. Figure 1 is a cross-sectional view showing an example of the configuration of the light emitting device according to the present embodiment. Figures 2 and 4 are cross-sectional views showing example configurations of light emitting devices of comparative examples.

[0013] The light-emitting device includes a substrate 8, a lens 17 disposed on the main surface of the substrate 8, and a light-emitting section 32 disposed between the main surface of the substrate 8 and the lens 17. A protective layer 13 and a color filter layer 15 may be disposed between the light-emitting section 32 and the lens 17. Either one of these layers, or a combination of two of these layers, may be considered a medium layer. The light-emitting section 32 includes, in this order from the substrate 8 side, a reflective layer 9, an organic layer 20, and a conductive layer 11.

[0014] The reflective layer 9 and the conductive layer 11 may be the first electrode and the second electrode of the light-emitting element, respectively. In the configuration example of Fig. 1, the reflective layer 9 has an inclined portion 21 that is inclined with respect to the main surface of the substrate. In the example of Fig. 1, the end of the inclined portion 21 and the end of the light-emitting portion 32 are aligned. The inclined portion 21 can be considered to have a positive inclination angle θ in the direction toward the vertex of the first lens.

[0015] The reflective layer 9 has a shape symmetrical about the center C1 of the light-emitting section 32, and can also be considered to have a cone-like shape. In the example of Fig. 1, in the cross-sectional view, the reflective layer 9 is linear from the center C1 to the end P1 of the inclined section 21. In other words, the reflective layer 9 has the same inclination angle θ1 from the center C1 to the end P1 of the inclined section 21.

[0016] In the comparative example of FIG. 2, the reflective layer 9 is formed in the shape of a flat plate parallel to the main surface of the substrate. That is, the comparative example of FIG. 2 does not have an inclined portion. In the embodiment of FIG. 1 and the comparative example of FIG. 2, the organic layer 20 and the conductive layer 11 are formed along the shape of the reflective layer 9. That is, in the example of FIG. 1, the organic layer 20 and the conductive layer 11 can also be considered to have inclined portions with an inclination angle θ. Similarly, the light-emitting portion 32 can also be considered to have an inclined portion with an inclination angle θ.

[0017] The surface of the protective layer 13 on the substrate 8 side is formed to follow the inclined portion, and the surface on the lens 17 side is formed parallel to the main surface of the substrate. In order to explain the shapes of the reflective layer 9 and the lens 17 in detail, components other than those described above are omitted in Figures 1 and 2, but the detailed configuration of the light-emitting device will be described later.

[0018] In a plan view perpendicular to the main surface S1 of the substrate 8, the light-emitting section 32 and the lens 17 are arranged so that they partially overlap. Also, as shown in FIG. 1, in the same plan view, the center of the light-emitting section 32 and the vertex 41 of the lens 17 do not overlap, but are arranged so that they have a distance B1 between them. The distance B1 is set appropriately depending on the light extraction angle required for the light-emitting device. Here, "position (member) A and position (member) B are arranged so that they have a distance X between them" does not include the case where the distance X is zero.

[0019] The center of the light-emitting section 32 can be defined as the position of the geometric center of gravity of the light-emitting section 32 in orthogonal projection onto the main surface S1 of the substrate 8. For example, the center of the light-emitting section 32 can be the midpoint of a line segment connecting one end of the light-emitting section to the other end in a cross section that passes through the vertex 41 of the lens 17 and is perpendicular to the main surface of the substrate 8.

[0020] The lens 17 may also be referred to as a microlens, etc. The upper surface of the lens 17 has a curved surface 40 that is convex in a direction away from the main surface P1 of the substrate 8. Light emitted obliquely from the light-emitting unit 32 in an outward direction (a direction away from the center of the light-emitting unit in a plan view perpendicular to the main surface P1 of the substrate 8) is converted into parallel light (collimated light) by refraction at the curved surface 40 of the lens 17, and can be extracted in the front direction. In other words, the lens 17 can function as a collimator. The lens 17 may have a light-collecting property. The lens 17 may have a positive power that converts the light emitted from the light-emitting unit 32 into parallel light or convergent light.

[0021] In this embodiment, the curved surface 40 may be a part of a sphere, or a part of an aspherical surface such as a paraboloid or a hyperboloid. Figures 1(a) and 2 show an example of the curved surface 40 being a part of a sphere, and Figure 1(b) shows an example of the curved surface 40 being an aspherical surface.

[0022] The convex curved surface 40 includes an end (second position, one end) 42, an end (other end 43), and a vertex 41 in a cross section perpendicular to the major surface of the substrate 8. The end 42 and end 43 of the curved surface 40 in the cross section may be the vertices of a portion of the curved surface 40 constituting the upper surface of the lens 17, which has a convex shape toward the substrate 8 in the peripheral portion of the lens 17. In this case, the vertex may be a point in the cross section where the slope of the approximation curve of the curved surface 40 is zero, or may be the vertex of a portion that points downward. In FIGS. 1(a) and 2, the end 42 and end 43 may be a set of points where the distance from the major surface P1 of the substrate 8 is minimal. Alternatively, they may be a set of points where the angle (lens surface angle α) formed by the tangent to the curved surface 40 of the lens 17 and the major surface S1 of the substrate 8 is maximized.

[0023] The vertex 41 of the curved surface 40 can be defined as the center of gravity of the surface on the curved surface 40 surrounded by the edge 42. In the example of FIGS. 1 and 2, the vertex 41 can also be considered to be the part of the curved surface 40 that constitutes the upper surface of the lens 17 that is farthest from the main surface P1 of the substrate 8. On the other hand, in the example of FIG. 4, the vertex 41 is not the part of the curved surface 40 that constitutes the upper surface of the lens 17 that is farthest from the main surface P1 of the substrate 8. FIGS. 1, 2, and 4 show a cross section that passes through the vertex 41 of the curved surface 40 that constitutes the upper surface of the lens 17 and is perpendicular to the main surface S1 of the substrate 8.

[0024] In the examples of Figures 1, 2, and 4, straight line L1 (first straight line) is a straight line that passes through both ends (ends 42 and 43) of lens 17, and straight line L2 (second straight line) is a straight line that extends in a direction perpendicular to straight line L1 and passes through vertex 41 of lens 17.

[0025] 1(a), 2, and 4 show examples in which the curved surface 40 of the lens 17 is part of a spherical surface and is symmetrical in cross section with respect to an axis of symmetry passing through the vertex 41. The symmetrical shape here allows for variations on the order of manufacturing errors. On the other hand, in FIG. 1(b), the curved surface 40 of the lens 17 is part of an aspherical surface and is not symmetrical with respect to a line passing through the vertex.

[0026] 1(a), 1(b), and 2, in the cross section, the tangent to vertex 41 of curved surface 40 is parallel to main surface S1 of the substrate. Also, straight line L2 is approximately perpendicular to the main surface of substrate 8. On the other hand, in the example of FIG. 3, in the cross section, the tangent to vertex 41 of curved surface 40 is not parallel to main surface S1 of the substrate. Also, straight line L2 is not perpendicular to the main surface of substrate 8, but has an inclination angle.

[0027] The effects of this embodiment will be described with reference to Figures 1, 2, 3, and 4. The angle between the ray of light emitted from light-emitting unit 32 and the perpendicular to the emission surface of light-emitting unit 32 is defined as the emission angle. The angle between the ray of light emitted from lens 17 and the perpendicular to the main surface of substrate 8 is defined as the extraction angle β.

[0028] 3 shows the position of curved surface 40 of lens 17 and the ray angle Φ of light passing therethrough when the extraction angle β is 0 degrees (when light emitted forward is extracted) and when the extraction angle β is 40 degrees (when light with an extraction angle β of 40 degrees shown in FIGS. 1 and 2 is extracted). In FIG. 3, the horizontal axis represents the X coordinate of curved surface 40 of lens 17, and the vertical axis represents the ray angle Φ. Here, in FIGS. 1 to 4, the coordinate in the direction parallel to the main surface of substrate 8 is defined as the X coordinate.

[0029] The output intensity of light emitted from the light-emitting unit 32 varies depending on the ray angle Φ. For example, as will be described later, in an organic light-emitting element having an optical resonator structure, the interference conditions change depending on the output angle from the light-emitting unit, so light with a large output angle may have a low output intensity. That is, as the output angle β increases, the proportion of light with a large output angle, i.e., light with a low output intensity, that is output increases accordingly, so the intensity of the output light may decrease. Therefore, the output intensity is highest when the ray angle Φ is 0 degrees (frontal output), and the intensity of the output light may decrease as the ray angle Φ increases (extraction in an oblique direction). The light-emitting device shown in FIG. 3 has such characteristics.

[0030] 3, when the extraction angle β is 0 degrees, the light ray angle Φ is 0 degrees at the position where the X coordinate is 0, and the light with the highest brightness is extracted from the light-emitting unit 32. As the X coordinate of the position of the curved surface 40 of the lens 11 moves away from 0, the light ray angle Φ also moves away from 0 degrees. In other words, the light emission intensity decreases.

[0031] When the take-off angle β is 40 degrees, the value of the ray angle Φ is approximately 19 degrees even at a position where the X coordinate is 0, and it is expected that the light output intensity will be smaller than when the take-off angle β is 0 degrees. For portions of the curved surface 40 of the lens 17 where the X coordinate is negative, the value of the ray angle Φ is 20 degrees or more, and is the same as or greater than the position on the X axis where the output intensity is largest when the take-off angle β is 0 degrees, which is expected to be the lowest. In other words, it can be seen that the output intensity will be smaller when the take-off angle β is greater than 0 (the light will be emitted at an angle).

[0032] Here, by tilting the reflective layer 9 toward the vertex 41 of the lens 17, the output angle can be reduced while maintaining the value of the output angle β. When light is emitted from the light-emitting unit 32, it is already tilted by the tilt angle θ, so the output angle required to achieve the light ray angle Φ can be reduced by the tilt angle θ. In this case, in the graph shown in FIG. 3, the line corresponding to the 40-degree output angle moves toward the line corresponding to the 0-degree output angle. Therefore, the output angle can be reduced for the portion with a large output angle where light is emitted from the position on the surface 40 of the lens 17 corresponding to the position on the X coordinate with a large negative value in FIG. 3.

[0033] Therefore, compared to the comparative example configuration shown in Figure 2 in which the reflective layer is not inclined with respect to the main surface of the substrate 8, the configuration shown in Figure 1 in which the reflective layer 9 has an inclined portion with an inclination angle θ has a higher emission intensity of light emitted from the lens 17.

[0034] That is, when the reflective layer 9 has an inclined portion that forms a positive inclination angle θ in the direction toward the vertex of the lens as shown in Fig. 1, the output angle of light that is refracted and extracted in the region to the left of the vertex 41 of the lens 17 can be made smaller when light is extracted at the same extraction angle β, compared to when the reflective layer 9 does not have an inclined portion as shown in Fig. 2. As a result, by configuring the reflective layer 9 to have an inclined portion, it is possible to improve the light extraction efficiency in oblique directions.

[0035] Note that when component (surface, line) A has an inclination angle with respect to component (surface, line) B, this refers to the case where component (surface, line) A is inclined and has an angle with respect to component (surface, line) B, and does not include the case where there is no angle (0 degrees) between component (surface, line) A and component (surface, line) B.

[0036] Furthermore, since light with a large emission angle may have lower color purity than light with a small emission angle, the above-mentioned effect of configuring the reflective layer 9 to have an inclined portion can improve the color purity of light extracted in an oblique direction.

[0037] A preferred range of the tilt angle θ1 will be described with reference to Figures 1, 2, 4, and 5. For simplicity, a case where the refractive index is uniform from the conductive layer 11 to the lens 17 will be described here, but even if the refractive indexes are different, the same consideration can be given, taking into account the refraction of light at the interface between each layer.

[0038] The tilt angle θ1 can be appropriately set according to the extraction angle required for the light-emitting device. A larger tilt angle θ1 is preferable because it increases the light extraction efficiency at wider angles. On the other hand, increasing the tilt angle θ1 may make it difficult to control the film thickness of the organic layer 20 and the conductive layer 11 formed along the tilt angle θ1. Furthermore, while increasing the tilt angle θ1 improves the light extraction efficiency in oblique directions, it may decrease the light extraction efficiency in the front direction. Therefore, from the viewpoint of simplifying the formation process of the organic layer 20 and the conductive layer 11, a smaller tilt angle θ1 is preferable.

[0039] Furthermore, as described above, when the light-emitting device is used as a display device such as a head-mounted display, it may be preferable to increase the light extraction efficiency in the oblique direction in the peripheral area of ​​the area (display area) where multiple light-emitting elements are arranged. On the other hand, it may be preferable to increase the light extraction efficiency in the front direction in the central area of ​​the display area. Therefore, as will be described later, in a configuration in which the reflective layer 9 has the same shape over the entire display area, it is preferable to reduce the inclination angle θ1 from the viewpoint of suppressing a decrease in the light extraction efficiency in the front direction in the central area of ​​the display area.

[0040] As explained above, the inclination angle θ1 needs to be set within an appropriate range. Consider the case where the intensity of light emitted from the light-emitting portion 32 is improved after being refracted at the vertex 41 of the lens 17 at an angle β. As shown in Figure 1, when the refraction of a light ray is traced from the light extraction side, the light ray reaches the inclined portion 21.

[0041] In this case, if the ray angle inside the lens is ray angle Φ, the exit angle is |Φ-θ1|. Therefore, when the tilt angle θ1 and the ray angle Φ are equal, the exit angle becomes 0, and the intensity of the light refracted at the vertex 41 of the lens 17 and extracted at an angle β can be maximized.

[0042] Here, if the inclination angle θ1 is greater than the ray angle Φ, the angle of emission will increase for the light that is refracted in the region to the right of the vertex 41 of the lens 17 (negative X coordinate) in Figure 1 and extracted at angle β. Therefore, the extraction efficiency of the entire light extracted at angle β will be lower than when the inclination angle θ1 and the ray angle Φ are the same.

[0043] Furthermore, as described above, a small tilt angle θ1 may be preferable in some cases from the viewpoint of simplifying the process of forming the organic layer 20 and the conductive layer 11. Therefore, it is preferable to set the tilt angle θ1 within a range not exceeding the light ray angle Φ = tilt angle θ1 at which the extraction efficiency in the oblique direction is maximized, that is, it is preferable to set the tilt angle θ1 within the range of tilt angle θ1≦light ray angle Φ.

[0044] In the cross-sectional view, the point on the surface of the inclined portion facing the lens 17 that is farthest from the vertex 41 of the lens 17 in a direction parallel to the main surface of the substrate 8 is defined as the first position P1. In this case, if the distance between the vertex 41 and the first position P1 in the parallel direction is defined as distance H1 and the distance in the vertical direction is defined as distance V1, then in order to satisfy the relation of inclination angle θ1≦light ray angle Φ, tan θ1

[0045] Therefore, as explained above, tanθ1

[0046] From another perspective, the condition of incident angle θ1≦light ray angle Φ can be satisfied by the following configuration. In the example of Fig. 1, it is preferable that the intersection point P0 between a line L2 that is perpendicular to a line L1 that passes through both ends (ends 42 and 43) of the lens and passes through the vertex 41 and a normal line at point P1 of the inclined portion 21 coincides with the vertex 41 of the lens, or is located closer to the light extraction side than the vertex 41. Here, point P1 is the point on the inclined portion 21 that is farthest from the vertex 41 of the lens 17 in a direction parallel to the main surface of the substrate 8.

[0047] Furthermore, in the cross section, it is preferable that the intersection of a line L2 that is perpendicular to a line L1 passing through both ends (ends 42 and 43) of the lens and passing through the vertex 41 and a normal to a certain point on the inclined portion 21 coincides with the vertex 41 of the lens, or is located closer to the light extraction side than the vertex 41. By setting the intersection P0 of the normal to point P1 (first position) and the symmetry axis L2 of the lens to coincide with the vertex 41 of the lens, or to be located closer to the light extraction side than the vertex 41, it is possible to improve the light extraction efficiency in oblique directions. Furthermore, θ1 can be set for a desired extraction angle β at any position on the inclined portion 21 based on the concept described above.

[0048] ​​Even when the inclined portion 21 is a curved surface as will be described later, the inclination angle of the inclined portion 21 is maximized by tan θ1

[0049] In the comparative example shown in Figure 4, line L2, which passes through vertex 41 of lens 17 and extends in a direction perpendicular to the line passing through both ends, is not perpendicular to the main surface of the substrate, and line L2 is parallel to the normal to inclined portion 21. In this configuration example, high-intensity light emitted from inclined portion 21 at an emission angle of zero is not refracted at vertex 41 of lens 17 and is extracted at the same angle, resulting in an insufficient effect of strengthening light in oblique directions. In the example of this embodiment shown in Figure 1, light emitted from inclined portion 21 at an emission angle of zero can be refracted at vertex 41 of lens 17 at a wider angle, thereby achieving the effect of strengthening light in oblique directions.

[0050] More specifically, a case will be described in which the reflective layer 9 has the same tilt angle θ1 in the example of this embodiment shown in Fig. 1 and the comparative example shown in Fig. 4. In the comparative example of Fig. 4, light that is emitted from the tilted portion at an emission angle of zero and passes through the vertex of the lens is extracted directly into the air at an extraction angle β = tilt angle θ1 because the tangent to the curved surface of the lens at the vertex is perpendicular to the light ray and is not refracted.

[0051] On the other hand, in the example of this embodiment shown in FIG. 1, if the refractive index of the lens and the medium layer is n2, the light emitted from the inclined portion at an emission angle of zero will have an extraction angle β=sin -1 The light is refracted at an angle of (n2·sinθ1) and can be extracted to the wider angle side. Similarly, the configuration shown in FIG. 1 has the effect of refracting light to the wider angle side at points other than the vertex of the curved surface of the lens. Therefore, compared to the example in FIG. 4, the configuration shown in FIG. 1 can improve the extraction efficiency in the oblique direction when the inclination angle θ1 is the same.​

[0052] The preferable relationship between the tilt angle θ1 and the refractive index n1 of the medium layer will now be explained. First, consider light refracted at the vertex 41 of lens 17. To consider the condition under which light with a ray angle Φ0 inside the lens can be extracted without total reflection, sinΦ0<1 / n2 holds, where n2 is the refractive index of lens 17. In other words, light with an angle equal to or greater than Φ0 inside the lens is totally reflected in the region to the right of the vertex 41 of lens 17, and is therefore not extracted to the outside.

[0053] According to Snell's law, the condition for the angle Φ1 of the light ray in the medium layer for extraction without total reflection is sinΦ2<1 / n1, where n1 is the refractive index of the medium layer. The inclination angle θ1 can be set to increase the desired extraction angle, but since the condition for light emitted from the inclined portion with inclination angle θ1 at an output angle of 0 to be extracted without total reflection at the vertex 41 of the lens 17 is θ1<Φ2, it is preferable to set sinθ1<1 / n1 from the perspective of improving the light extraction efficiency.

[0054] The medium layer may be composed of multiple layers and may have multiple functions, such as a protective layer, a color filter layer, a planarization layer, etc. When the medium layer is composed of multiple layers, the refractive index n1 of the medium layer may be substituted with the refractive index of the layer in contact with the second electrode 11.

[0055] A preferred range of the distance H1 in the direction parallel to the main surface between the lens vertex 41 and the substrate 8 at the first position P1 will be described below. Considering the light that is emitted from the first position P1 and extracted by being refracted at the lens vertex 41, a larger distance H1 is preferred from the viewpoint of improving the extraction efficiency in oblique directions, since the extraction angle β can be increased by refraction.

[0056] On the other hand, if the refractive index of the lens 17 is n2, the distance H1 is V1 / (n2 2 -1) 1 / 2 If the angle is greater than 0.05, the light that leaves the first position P1 and reaches the vertex 41 of the lens will be totally reflected. 2 -1) 1 / 2 ​It is preferable to set the distance in the range of a to improve the extraction efficiency in the oblique direction. 2 -1) 1 / 2 It is more preferable to set it in the range of

[0057] A preferred shape of the curved surface 40 of the lens 17 in this embodiment will be described. As described above, when the range of emission angles of the extracted light at the light-emitting unit is wide, the deviation in the interference condition becomes large, which may result in a decrease in the emission intensity and a decrease in the extraction efficiency. That is, in this embodiment, in order to increase the extraction efficiency at the desired extraction angle β, it is preferable that the range of emission angles at the light-emitting unit of the light that is refracted by the curved surface 40 of the lens 17 and extracted at angle β is narrow.

[0058] When considering light refracted by the curved surface 40 of the lens 17 from a direction perpendicular to the main surface of the substrate on the light extraction side (front direction), and considering the position where the light is collected as the focal point, narrowing the range of the emission angle can be rephrased as increasing the distance from the focal point to the lens 17. Therefore, it is preferable to set the focal point at a position farther from the light extraction side, and in particular, it is preferable to set the focal point at a position farther from the light extraction side than the first position P1. By setting the focal point at a position farther from the light extraction side than the first position P1, the range of the emission angle can be narrowed, and the extraction efficiency can be improved.

[0059] The focal position can be defined as the position where two light rays that pass through the vertex 41 and end 42 of the lens and are emitted in the front direction of the light extraction side intersect when the light rays are incident from the light extraction side to the vertex 41 and end 42. At end 42 of curved surface 40, the angle between the tangent to lens 17 and the main surface of the substrate (lens surface angle α) can be the largest among curved surface 40.

[0060] ​Let the horizontal distance from the vertex 41 of the lens to the end 42 be H2, and the vertical distance from the first position P1 to the end 42 be V2. Also, when tracing the light ray that passes through the end 42 and exits in the direction perpendicular to the main surface of the substrate in the direction from the second position towards the light emitting part, when moving a distance V2 in the direction perpendicular to the main surface of the substrate from the end 42, let the distance traveled in the horizontal direction on the main surface of the substrate be the distance A. That is, in the light ray that passes through the second position and exits in the direction perpendicular to the main surface of the substrate 8, the distance from the second position in the direction parallel to the main surface at a position that is a distance V2 away from the second position in the direction perpendicular to the main surface is A.

[0061] In this case, by satisfying the relationship A < H2, the focal position can be set at a position farther from the light extraction side than the first position P1. Therefore, by satisfying the relationship A < H2, the extraction efficiency in the oblique direction can be improved, which is preferable.

[0062] An explanation will be given on how to obtain the distance A when the medium layer is composed of a plurality of layers with different refractive indices. The distance A can be approximately obtained by calculating the angles of the light rays in each layer in consideration of the refraction at the interfaces of each layer. Specifically, if the lens surface angle at the end 42 is α, the incident angle of the light in the front direction to the end 42 is α. Also, for the refraction angle γ, using the refractive index n0 of the layer (here air) that contacts the lens 17 on the light extraction side and the refractive index n2 of the lens 17, from Snell's law, there is a relationship of n2·sinγ = n0·sinα.

[0063] Using this refraction angle γ, the angle β1 with respect to the front direction inside the lens 17 is obtained as β1 = |α - γ|. When there are N layers including the layer of the lens 17, taking the layer of the lens 17 as the first layer, and setting the refractive index of the i-th layer from there towards the substrate 8 as ni, the light ray angle βi in the i-th layer is obtained by the following formula.

[0064] ni·sinβi = n1·sinβ1 The distance Ai that the light travels in a direction parallel to the main surface S1 of the substrate 8 in each layer is obtained by Ai = Ti·tanβi using the light ray angle βi in each layer and the distance (thickness) Ti in the direction perpendicular to the main surface of the substrate in each layer. Since the distance A is obtained by adding up the distances Ai of each layer from i = 1 to i = N, the distance A is approximately expressed by the following formula.

[0065] A = T1·tanβ1 + T2·tanβ2 + ··· + T N ·tanβ N That is, when the medium layer is composed of a plurality of layers with different refractive indices, by using A obtained by the above formula and satisfying the relationship of A < H2, the light extraction efficiency in the oblique direction is improved.

[0066] Also, the extraction angle β of the light ray refracted and extracted at a point on the curved surface with the lens surface angle α is limited to the range of β ≦ 90 - α. Therefore, a point with a large lens surface angle α cannot contribute to wide-angle extraction. Thus, setting the lens surface angle α to α < 90° at the end 42 of the lens is preferable in terms of increasing the proportion that can contribute to light extraction to the wide-angle side in the lens 17, and it is more preferable that α < 70°.

[0067] Referring to FIGS. 5(a) to 5(c), a configuration example in the case of arranging a plurality of light-emitting elements will be described. FIG. 5(a) is a plan schematic view of the light-emitting device of this embodiment in which a plurality of light-emitting elements are arranged, viewed from a direction perpendicular to the main surface of the substrate, and FIG. 5(b) is a cross-sectional schematic view of the broken-line part in FIG. 5(a) in one example of this embodiment. FIG. 5(c) is a cross-sectional schematic view of the broken-line part in FIG. 5(a) in another example of this embodiment.

[0068] As described above, when a light-emitting device is combined with an optical system and used as a display device, light extracted in a front direction of the substrate may be used near the center of the display region 200 where multiple light-emitting elements are arranged, while light extracted in a direction oblique to the substrate may be used in the peripheral portion of the display region. In such a case, as shown in Figures 5(a) to 5(c), the centers of the light-emitting units and the vertices of the corresponding lenses may be arranged so as to overlap in a plan view at the center of the display region 200. Furthermore, the distance between the centers of the light-emitting units and the vertices of the corresponding lenses in a direction parallel to the main surface of the substrate 8 may be increased depending on the distance from the center of the display region.

[0069] In this case, in a plan view, the direction from the center of the light-emitting section toward the vertex of the corresponding lens roughly coincides with the direction from the center of the display area 200 toward the center of the light-emitting section. Similarly, in a plan view, the direction from the center of the light-emitting section toward the vertex of the corresponding lens roughly coincides with the direction from the center of the display area 200 toward the vertex of the lens. The reflective layer 9 may have the same shape throughout the display area 200, or may have a different shape depending on the position within the display area 200 where the light-emitting element is arranged.

[0070] 5(b), the reflective layer 9 may be cone-shaped and have the same inclination angle throughout the display area 200. Having the same shape and inclination angle throughout the display area 200 facilitates the process of forming the reflective layer 9 and also improves the uniformity of the film thickness between the light-emitting elements of the organic layer 20 and the conductive layer 11 that are formed on the reflective layer 9, which is preferable from the viewpoint of simplifying the formation process.

[0071] From another perspective, the set of the first light-emitting unit and the first lens arranged on the periphery of the display region 200 is referred to as the first set, and the set of the second light-emitting unit and the second lens arranged near the center of the display region 200 is referred to as the second set. In this case, in a plan view, the distances from the vertices of the respective lenses to the first points of the farthest inclined portions in a direction parallel to the main surface of the substrate 8 are defined as distances H1 and H2, the distances in the vertical direction are defined as distances V1 and V2, and the inclination angles are defined as θ1 and θ2.

[0072] In this case, in the example shown in Figure 5(b), the relationships are H1 > H2, V1 = V2, and θ1 = θ2. Therefore, the relationship V2 tan θ2 / H2 > V1 tan θ1 / H1 is satisfied. This configuration is preferable because it maintains uniformity in the film thickness of the organic layer 20 and the conductive layer 11 between each light-emitting element, while effectively utilizing refraction at the lens toward the periphery of the display area 200 to increase the extraction efficiency toward the wide-angle side.

[0073] As another example, as shown in Fig. 5(c), a configuration may be adopted in which the shape of the reflective layer 9 changes depending on the position in the display region 200 where the light-emitting elements are formed. In the example shown in Fig. 5(c), the reflective layer 9 is flat, and the inclination angle θ is small near the center of the display region 200, and the inclination angle θ increases as the distance from the center of the display region 200 increases. A configuration may be adopted in which there is no inclined portion in the center of the display region 200.

[0074] This configuration is preferable because it increases the extraction efficiency in the radiation angle direction required for each light-emitting element. In this example, when the distances H1, H2, V1, and V2, and the tilt angles θ1 and θ2 are defined in the same manner as in the above example, the relationships H1>H2, V1=V2, and θ1>θ2 are satisfied. In this case, the relationship V2·tanθ2 / H2≦V1·tanθ1 / H1 may be satisfied, and satisfying this relationship is preferable because it optimizes the extraction efficiency in the radiation angle direction required for each light-emitting element.

[0075] The display region 200 may also have multiple regions with different tilt angles θ. In this case, the reflective layer 9 in a second region farther from the center of the display region 200 than the first region may have a tilt angle greater than the tilt angle of the reflective layer 9 in the first region. This configuration is preferable because it can effectively utilize refraction at the lens toward the periphery of the display region 200 to increase the extraction efficiency toward the wide-angle side while maintaining uniformity in the film thickness of the organic layer 20 and the conductive layer 11 between the light-emitting elements.

[0076] The preferred refractive index range of the medium layer in the case where a medium layer having a refractive index different from that of the lens 17 is provided between the light emitting portion 32 and the lens 17 will be described with reference to FIGS. 6 and 7. FIGS. 6 and 7 are diagrams showing a configuration example in the case where medium layers 35a and 35b having different refractive indexes are provided between the light emitting portion 32 and the lens 17. Here, it is assumed that the refractive index of the lens 17 is n2, the refractive index of the medium layer 35a is n3, and the refractive index of the medium layer 35b is n4. For example, the medium layer 35a may be a color filter. Also, for example, the medium layer 35b may be a protective layer.

[0077] In the configuration shown in FIG. 6, the magnitude relationship of the refractive indexes is n3 < n2 < n4. Considering the refraction of the light rays emitted obliquely from the light emitting portion 32, according to the magnitude relationship of the refractive indexes, the magnitude relationship of the angles a, b, and c is a < c < b. Here, since c < b, the light rays are bent in a direction closer to the front at the interface between the medium layer 35a and the lens 17.

[0078] Therefore, as shown in FIG. 6, the light emitted from the light emitting portion 32 may be emitted from the lens 17 of the adjacent light emitting element in a direction closer to the front. Therefore, crosstalk between the light emitting elements may occur, and the image quality may deteriorate. Also, since the radiation angle from the light emitting portion 32 is large and light with poor color purity is likely to be visually recognized, the color purity may decrease.

[0079] On the other hand, in the configuration shown in FIG. 7, the magnitude relationship of the refractive indexes is n2 < n3 < n4. Therefore, the magnitude relationship of the angles a, b, and c is a < b < c, and the light emitted obliquely from the light emitting portion 32 is refracted toward the wider angle side at the interface between the medium layer 35a and the lens 17 and is less likely to be emitted in the front direction. Therefore, a decrease in color purity can be suppressed.

[0080] As described above, crosstalk between light-emitting elements and a decrease in color purity can be suppressed by not disposing any layer between light-emitting section 32 and lens 17 whose refractive index is smaller than the refractive index n1 of lens 17. For example, in the configuration shown in FIG. 7, the refractive index n2 of lens 17 and the refractive index n3 of medium layer 35a may satisfy the relationship n2≦n3. Furthermore, the refractive index n4 of medium layer 35b disposed between medium layer 35a and light-emitting section 32 may satisfy the relationship n2≦n4. Furthermore, the refractive index n4 of medium layer 35b may satisfy the relationship n3≦n4.

[0081] An example of the shape of the reflective layer 9 in this embodiment will be described with reference to FIG. 8. FIG. 8(a) is a schematic diagram of the reflective layer 9 and related parts in the configuration example of FIG. 1. FIGS. 8(b) to 8(e) are schematic diagrams showing the reflective layer 9 and related parts in another configuration example of this embodiment. The examples shown in FIGS. 8(a) to 8(e) show the inclined portion 21, first position P1, and inclination angle θ1 when the apex of the lens is shifted leftward relative to the center of the light-emitting section. As described above, the reflective layer 9 has an inclined portion in the direction facing the apex of the lens. This inclination can reduce the output angle from the light-emitting section, improving the light extraction efficiency as described above and enabling light with high color purity to be extracted. Hereinafter, as shown in FIG. 8, the inclination angle θ1 of the tangent of the reflective surface at the first position P1 relative to the main surface P1 of the substrate 8 is defined as a positive value (0°<θ1<90°) in the direction facing the apex of the lens.

[0082] The reflective layer 9 only needs to have a reflective surface on the light extraction side that is inclined in the direction of the lens vertex relative to the main surface P1 of the substrate 8, and may have an inclination in opposite directions with the center of the light-emitting section as a boundary, as in the examples of Figures 8(a) and 8(c). Alternatively, as in the example of Figure 8(b), the inclination angle θ1 may vary continuously or may be zero at the center of the light-emitting section. Alternatively, as in the example of Figure 8(e), the inclination angle θ1 may be constant. Alternatively, as in the example of Figure 8(d), the reflective layer 9 may have a non-inclined region.

[0083] An example of the planar shapes of the reflective layer 9, the light-emitting portion 32, and the inclined portion 21 in this embodiment when orthogonally projected onto the main surface of the substrate will be described with reference to Fig. 18. Fig. 18(a) is a schematic diagram showing the planar shapes in the configuration example of Fig. 8(d). Fig. 8(d) is a cross-sectional view taken along line D-D' in Fig. 18(a). Figs. 18(b) to (d) are schematic diagrams extracting the planar shapes of the reflective layer 9, the light-emitting portion 32, and the inclined portion 21 in another configuration example of this embodiment.

[0084] 18(a) to 18(d), the planar shape of the reflective layer 9 is hexagonal, but is not limited thereto and may be a polygon such as a rectangle, or a circle or an ellipse. For the purpose of simplifying the design, the planar shape of the reflective layer 9 may be a polygon similar to the shape of the sub-pixels corresponding to the pixel arrangement described below so that the distance between adjacent reflective layers is constant. For example, when the pixel arrangement is a delta arrangement, the planar shape of the reflective layer 9 may be hexagonal.

[0085] The exposed portion of the first electrode (reflective layer 9) of the light-emitting element that is not covered by the insulating layer 12 is the light-emitting section 32. The planar shape of the light-emitting section 32 is circular in the examples shown in FIGS. 18(a) to 18(d), but is not limited thereto and may be a polygon such as a rectangle or a hexagon, or an ellipse. It may also be a shape such as a ring surrounded by two shapes. The two shapes may be circles, polygons, or ellipses, and may be similar shapes or different dissimilar shapes. From the viewpoint of enhancing the symmetry of the radiation angle characteristics, the more symmetric the planar shape of the light-emitting section 32, the better. From this viewpoint, a regular polygon is preferable, and a circle is more preferable.

[0086] 18(a) to (d) show areas that can function as inclined portion 21. The reflective layer 9 is inclined with respect to the main surface of the substrate, and the area that overlaps with light-emitting portion 32 in orthogonal projection onto the main surface of the substrate can function as inclined portion 21. The reflective layer 9 may be parallel to the main surface of the substrate except for the area of ​​light-emitting portion 32 that can function as inclined portion 21. The outer edge of the area that can function as inclined portion 21 and the outer edge of light-emitting portion 32 do not coincide in the example shown in FIG. 18(a), but coincide in the example shown in FIG. 18(b).

[0087] Since a large proportion of the light extracted in oblique directions is emitted from the region close to the outer edge of the light-emitting section 32, the effect of improving the light extraction efficiency in oblique directions is greater by providing the inclined section 21 in the region close to the outer edge. Therefore, from the perspective of improving the light extraction efficiency in oblique directions, it is preferable that the outer edge of the light-emitting section 32 coincides with the outer edge of the region other than the region that can function as the inclined section 21.

[0088] In the examples shown in Figures 18(c) and (d), the planar shape of the area that can function as inclined portion 21 is a circle. Figure 18(c) shows an example in which the outer edge of the area that can function as inclined portion 21 does not coincide with the outer edge of light-emitting portion 32. Figure 18(d) shows an example in which the outer edge of the area that can function as inclined portion 21 coincides with the outer edge of light-emitting portion 32.

[0089] Fig. 18(d) corresponds to the example shown in Figs. 8(a) to (c) and 8(e). The planar shape of the region that can function as inclined portion 21 is not limited to a ring or a circle, but may be a polygon or an ellipse, or a shape surrounded by two polygons or ellipses. From the viewpoint of improving the symmetry of the radiation angle characteristics, it is preferable that the planar shape of the region that can function as inclined portion 21 is similar to the planar shape of light-emitting portion 32, or a shape surrounded by two figures that are similar to the planar shape of light-emitting portion 32. Therefore, when light-emitting portion 32 is circular, it is preferable that the planar shape of the region that can function as inclined portion 21 is a circle or annulus.

[0090] The area ratio of the light-emitting section 32 occupied by the region that can function as the inclined section 21 may be set appropriately in the range of more than 0% and less than 100% in consideration of the balance between the light extraction efficiency in the front direction and the oblique direction, but is preferably 50% or more in consideration of improving the light extraction efficiency in the oblique direction. Furthermore, when multiple sub-pixels that emit different colors are arranged, the area ratio of the light-emitting section 32 occupied by the inclined section may be made different for each sub-pixel in order to reduce the difference in chromaticity between the front direction and the oblique direction.

[0091] As a method for forming the inclined portion of the reflective layer 9, a shape having an inclined portion can be formed by forming a reflective layer on the flat substrate 8 or on an insulating layer having a flat upper surface disposed on the substrate, and then combining photolithography and etching. Alternatively, the inclined portion of the reflective layer 9 can be formed by first forming an inclined portion in an insulating film laminated on the substrate 8 using photolithography and etching, and then forming a reflective layer along that shape.

[0092] More specifically, the sloped portion can be formed by forming resist layers of different thicknesses on a reflective layer 9 having an upper surface parallel to the main surface of the substrate, followed by etching back. Resist layers of different thicknesses can be formed by exposure using an area gradation mask. Alternatively, an insulating film having a sloped portion can be formed by forming resist layers of different thicknesses on an insulating film stacked on a substrate 8, followed by etching back. Figures 8(a), 8(c), and 8(d) show examples of a configuration using a reflective layer 9 having an upper surface parallel to the main surface of the substrate, while Figures 8(b) and 8(e) show examples of a configuration in which a sloped portion is formed in advance in the insulating film on the substrate. A more specific example of the configuration of the light-emitting device will be described. The light-emitting device may include a substrate 8, a reflective layer (first electrode) 9, an organic layer 20, a conductive layer (second electrode) 11, an insulating layer 12, a protective layer 13, a planarization layer, a color filter 15, a planarization layer, and a lens 17. In this example, the reflective layer 9 and the conductive layer 11 function as the first electrode and the second electrode, respectively. A reflective layer 9 serving as a first electrode is disposed on the substrate 8. The reflective layer 9 serving as a first electrode may also be called a lower electrode.

[0093] The organic layer 20 includes a light-emitting layer containing a light-emitting material. A portion of the organic layer 20 (light-emitting layer) functions as the light-emitting section 32 described above. The organic layer 20 is disposed between the substrate 8 and the lens 17 so as to cover the reflective layer 9 serving as a first electrode. The conductive layer 11 serving as a second electrode is disposed on the organic layer 20. The conductive layer 11 serving as the second electrode may also be referred to as an upper electrode. The organic layer 20 (light-emitting layer) emits light due to the potential difference between the first electrode (reflective layer 9) and the second electrode (conductive layer 11).

[0094] The insulating layers 12 are disposed between adjacent first electrodes (reflective layers 9) so that the adjacent first electrodes (reflective layers 9) are insulated from each other. The insulating layers 12 may also be called banks. The insulating layers 12 are disposed on the outer edges of the first electrodes (reflective layers 9). The exposed portions of the first electrodes (reflective layers 9) that are not covered by the insulating layers 12 are in contact with the organic layer 20. The portions of the organic layer 20 that are in contact with the first electrodes (reflective layers 9) can serve as the light-emitting sections 32 described above. Therefore, the light-emitting device can be provided with a plurality of light-emitting sections 32 that respectively correspond to a plurality of first electrodes (reflective layers 9).

[0095] The protective layer 13 is disposed on the second electrode (conductive layer 11), and the planarization layer is disposed on the protective layer 13. The color filters 15 can be disposed on the planarization layer so as to correspond to the plurality of light-emitting sections 32, respectively. The planarization layer is disposed on the color filters 15. The lenses 17 are disposed on the planarization layer. The lenses 17 are disposed so as to correspond to the plurality of light-emitting sections 32, respectively.

[0096] The material used for the substrate 8 is not particularly limited as long as it can support each component of the light-emitting device, such as the first electrode (reflective layer 9), the organic layer 20, and the second electrode (conductive layer 11). For example, glass, plastic, silicon, etc. may be used as the material for the substrate 8. A switching element such as a transistor, a wiring pattern, an interlayer insulating film, etc. may be provided on the substrate 8.

[0097] The first electrode (reflective layer 9) may be transparent or opaque. When the first electrode (reflective layer 9) is opaque, the material of the first electrode (reflective layer 9) may be a metal material having a reflectance of 70% or more at the wavelength of light emitted from the light-emitting section 32. For example, the material of the first electrode (reflective layer 9) may be a metal such as Al or Ag, or an alloy of Al or Ag with Si, Cu, Ni, Nd, or the like. The first electrode may also be a transparent electrode such as ITO, IZO, AZO, or IGZO, in which case the first electrode and the reflective layer 9 may be stacked.

[0098] When the transparent first electrode and the reflective layer 9 are formed by laminating them as separate layers, the first electrode is formed along the reflective layer 9, and the top surface of the first electrode and the top surface of the reflective layer 9 may be parallel to each other, or they may not be parallel to each other. In order to make the optical distance (described later) uniform within the light-emitting section 32, it is preferable that the top surface of the first electrode and the top surface of the reflective layer 9 are parallel to each other. The first electrode and the reflective layer 9 may or may not be electrically connected to each other.

[0099] When the first electrode and the reflective layer 9 are not electrically connected, a transparent insulating layer may be disposed between the first electrode and the reflective layer 9. The transparent insulating layer may be formed of an inorganic material such as silicon oxide or silicon nitride. Even when the first electrode and the reflective layer 9 are electrically connected, a transparent insulating layer may be disposed between the first electrode and the reflective layer 9 in the region of the light-emitting section 32 when orthogonally projected onto the main surface of the substrate, and the first electrode and the reflective layer 9 may be electrically connected in the region outside the light-emitting section 32.

[0100] When the first electrode and the reflective layer 9 are electrically connected, the first electrode and the reflective layer 9 may be in direct contact with each other, may be connected via another conductive layer, or may be connected via an element such as a transistor.

[0101] The first electrode (reflective layer 9) may be a laminated electrode with a barrier electrode made of a metal such as Ti, W, Mo, or Au or an alloy thereof, or may be a laminated electrode with a transparent oxide film electrode made of ITO or IZO, as long as the required reflectivity is obtained. To optimize the optical path length, which will be described later, the reflective layer 9 as the first electrode may have a configuration in which an insulating film is provided between the reflective layer and a transparent conductive film.

[0102] The second electrode (conductive layer 11) may be a semi-transparent electrode that transmits part of the light that reaches the conductive layer 11 and reflects the other part (i.e., semi-transparent and reflective). The second electrode (conductive layer 11) may be made of a transparent material such as a transparent conductive oxide. The second electrode (conductive layer 11) may also be made of a semi-transparent material such as an elemental metal (Al, Ag, Au, etc.), an alkali metal (Li, Cs, etc.), or an alkaline earth metal (Mg, Ca, Ba, etc.). The second electrode (conductive layer 11) may also be made of a semi-transparent material such as an alloy containing these metal materials.

[0103] When a semi-transparent material is used as the material for the second electrode (conductive layer 11), an alloy containing Mg or Ag as a main component may be used as the semi-transparent material. As long as the second electrode (conductive layer 11) has an appropriate transmittance, the second electrode (conductive layer 11) may have a laminated structure of multiple layers made of the materials described above. In the configuration shown in FIG. 1, a second electrode (conductive layer 11) is provided that is common to multiple light-emitting sections 32. However, this is not limited to this, and multiple second electrodes (conductive layers 11) may be provided corresponding to multiple light-emitting sections 32, respectively.

[0104] One of the first electrode (reflective layer 9) and the second electrode (conductive layer 11) functions as an anode, and the other of the first electrode (reflective layer 9) and the second electrode (conductive layer 11) functions as a cathode. For example, the first electrode may function as an anode and the second electrode may function as a cathode. Alternatively, the first electrode may function as a cathode and the second electrode may function as an anode.

[0105] The organic layer 20 can be formed by known techniques such as vapor deposition and spin coating. The organic layer 20 may be composed of multiple layers. When the organic layer 20 is an organic compound layer, the organic layer 20 may be composed of at least one of a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., in addition to an emitting layer.

[0106] The light-emitting layer emits light by recombining holes injected from the anode and electrons injected from the cathode within the light-emitting layer. The light-emitting layer may be a single layer or multiple layers. For example, when a light-emitting layer containing a red light-emitting material, a light-emitting layer containing a green light-emitting material, and a light-emitting layer containing a blue light-emitting material are combined, the light from each light-emitting layer (red light, green light, blue light) mixes to produce white light. Two types of light-emitting layers whose emitted colors are complementary to each other (for example, a light-emitting layer containing a blue light-emitting material and a light-emitting layer containing a yellow light-emitting material) may also be combined.

[0107] 1 shows a configuration in which each light-emitting section 32 emits white light and is colored by the color filter 15. However, this is not limited to this. The material contained in the light-emitting layer or the configuration of the light-emitting layer may be different for each light-emitting section 32 so that the light-emitting layer emits light of a different color for each light-emitting section 32. In this case, the light-emitting layer may be patterned for each light-emitting section 32.

[0108] Alternatively, the organic layer 20 may have a so-called tandem structure, in which a plurality of light-emitting layers and a charge generating layer provided between the plurality of light-emitting layers are included. By adopting a tandem structure, the plurality of light-emitting layers can emit light simultaneously, thereby improving the luminous efficiency.

[0109] The light emitting device includes a reflective layer 9 arranged between an organic layer 20 including a light emitting layer and a main surface P1 of a substrate 8, and a conductive layer 11 arranged between the organic layer 20 including a light emitting layer and a lens 17. The reflective layer 9 may be a first electrode, or may be a metal layer or the like arranged between the first electrode and the substrate 8. The conductive layer 11 may be a second electrode, or may be a semi-transmissive reflective layer arranged between the second electrode and the lens 17 and having the property of transmitting part of the light that reaches the conductive layer 11 and reflecting the other part (i.e., semi-transmissive reflectivity).

[0110] In order to optimize the optical distance between the first reflective surface, which is the upper surface of the reflective layer 9, and the light-emitting region (light-emitting position) of the organic layer 20 including the light-emitting layer, it is sufficient to satisfy the following formula (8). In formula (8), the optical distance Lr is the optical path length (optical distance) from the first reflective surface, which is the upper surface of the reflective layer 9, to the light-emitting position of the organic layer 20, the phase shift Φr is the phase shift when light of wavelength λ is reflected by the first reflective surface, and m is an integer equal to or greater than 0. The film thickness between the reflective layer 9 and the organic layer, the film thickness of each layer of the organic layer, etc. may be optimized so as to satisfy formula (8).

[0111] Lr=(2×m-(Φr / π))×(λ / 4)···(8) Furthermore, the optical distance Ls from the light-emitting position to the second reflecting surface, which is the lower surface of the conductive layer 11, should satisfy the following equation (9), where Φs is the phase shift when light of wavelength λ is reflected by the second reflecting surface, and m' is an integer greater than or equal to 0.

[0112] Ls=(2×m'-(Φs / π))×(λ / 4)...(9) Therefore, the total layer interference L from the first reflecting surface to the second reflecting surface should satisfy the following formula (10), where m is an integer greater than or equal to 0. In formula (10), Φ is the sum of the phase shift Φr and the phase shift Φs.

[0113] L=Lr+L=(2×m-Φ / π)×(λ / 4) (10) Here, in the above formulas (8) to (10), the allowable range is about λ / 8 or about 20 nm. Since it may be difficult to identify the light-emitting position of the organic layer 20, in the above example, the light-emitting position is substituted with the interface on the first reflecting surface side or the interface on the second reflecting surface side of the light-emitting layer. Considering the allowable range, even when substituted in this way, the effect of intensifying light can be obtained.

[0114] The protective layer 13, the planarization layer, the color filter 15, and the planarization layer constitute the above-mentioned medium layer. The protective layer 13 is a dielectric layer. The protective layer 13 is also light-transmitting. Furthermore, the protective layer 13 may contain an inorganic material that has low permeability to oxygen and moisture from outside the light-emitting device. For example, the protective layer 13 may be made of silicon nitride (SiN), silicon oxynitride (SiON), silicon oxide (SiO x The protective layer 13 may be formed using an inorganic material such as silicon dioxide (SiO2), aluminum oxide (Al2O3), or titanium oxide (TiO2). In terms of protective performance, the protective layer 13 may be formed using an inorganic material such as silicon nitride (SiN), silicon dioxide (SiO2), or Al2O3. The protective layer 13 may be formed using a chemical vapor deposition (CVD) method, an atomic layer deposition (ALD) method, a sputtering method, or the like.

[0115] The protective layer 13 may have a single layer structure using the above-mentioned materials, or a laminate structure combining the above-mentioned materials, as long as it has sufficient moisture-blocking properties. For example, the protective layer 13 may have a laminate structure of a silicon nitride layer formed using a CVD method and another high-density layer (e.g., Al2O3) formed using an ALD method. Furthermore, the protective layer 13 may include an organic layer as long as it has moisture-blocking properties. Examples of the organic layer include polyacrylate, polyimide, polyester, and epoxy. Furthermore, although the configuration shown in FIG. 1 provides a common protective layer 13 among the multiple light-emitting sections 32, multiple protective layers 13 may be provided corresponding to the multiple light-emitting sections 32, respectively.

[0116] The lens 17 can be formed by an exposure process and a development process. Specifically, a material film (e.g., a photoresist film) for the lens 17 is formed, and the photoresist film is exposed and developed using a mask with a continuous gradation change. A gray mask can be used as the mask used to form the lens 17. An area gradation mask, which changes the density distribution of dots in a light-shielding film below the resolution of the exposure device and enables light irradiation with a continuous gradation change on the imaging plane, can also be used as the mask used to form the lens 17.

[0117] Furthermore, the lens shape can be adjusted by etching back the lens 17 formed by the exposure process and development process. As described above, the upper surface of the lens 17 only needs to have a curved surface 40 that has light-collecting properties, and the curved surface 40 may be a part of a spherical surface or may be an aspherical surface.

[0118] The layer in contact with the lens 17 on the light extraction side may be a gas such as air, or may be a resin, etc. It is preferable that the layer has a lower refractive index than the lens 17, and may be a resin with hollow particles dispersed therein, etc.

[0119] A light-emitting element is formed by combining light-emitting portions 32, curved surface 40 of lens 17, etc. When multiple light-emitting elements are provided, the planar arrangement of the multiple light-emitting elements (the arrangement when viewed from the normal direction of the main surface of substrate 8) may be any of a stripe arrangement, a square arrangement, a delta arrangement, a pentile arrangement, a Bayer arrangement, etc. Figures 9A to 9C are plan views of the light-emitting device viewed from the lens 17 side, showing an example of a planar arrangement of multiple light-emitting elements.

[0120] FIG. 9A shows an example of a delta arrangement. FIG. 9B shows an example of a stripe arrangement. FIG. 9C shows an example of a Bayer arrangement. Here, consider a case where a light-emitting device is used as a display panel, and one pixel (main pixel) is configured to include multiple sub-pixels that correspond to different color components (for example, a sub-pixel that displays red, a sub-pixel that displays green, and a sub-pixel that displays blue). In this case, as shown in FIG. 9B, multiple light-emitting elements may be arranged in one sub-pixel.

[0121] The size and shape of the curved surface 40 of the lens 17 may be set appropriately depending on the planar arrangement of the plurality of light-emitting elements. For example, when a delta arrangement is adopted, the area occupied by the curved surface 40 of the lens 17 can be set larger relative to the subpixel, thereby improving the light extraction efficiency.

[0122] In the configurations shown in FIGS. 9A to 9C, the planar shape of the light-emitting section 32 (the shape when viewed from the normal direction to the main surface of the substrate 8) is circular, but the planar shape of the light-emitting section 32 is not limited to this. The planar shape of the light-emitting section 32 may be polygonal, such as a square or a hexagon. However, if the planar shape of the light-emitting section 32 is circular, the relationship of the inclination angle from the end of the light-emitting section 32 to the end 42 of the curved surface 40 of the lens 17 will be the same in all cross sections obtained by the plane in the normal direction to the main surface of the substrate 8 that passes through the vertex 41 of the curved surface 40. This may facilitate the design of the light-emitting device.

[0123] 1, the lenses 17 may be formed so that the end portions 42 of the curved surface 40 constituting the upper surface of the lenses 17 have a thickness (so that adjacent lenses 17 partially overlap). In this case, the end portions 42 and 43 of the curved surface 40 may be a collection of portions where the inclination between adjacent lenses 17 is 0° (parallel to the main surface of the substrate 8).

[0124] As described above, a configuration may be adopted in which light of different colors is transmitted by the lens 17. A full-color display is possible in the light-emitting device. A method of realizing a full-color display may be a method using a light-emitting layer that emits white light and a color filter 15. Because the light-emitting layer can be shared among multiple light-emitting sections 32, the manufacturing process of the light-emitting layer is easier than when the light-emitting layer is patterned to emit light of different colors for each light-emitting section 32.

[0125] The light-emitting layer may be patterned so that the plurality of light-emitting sections 32 emit light of different colors. The optical path length L (optical path lengths Lr, Ls) between the reflective layer and the conductive layer may be different for each of the light-emitting sections 32 that emit light of different colors.

[0126] As described above, the center of the light-emitting section 32 and the center of the lens 17 may be arranged to be offset from each other in order to increase the light extraction efficiency in oblique directions. They may be arranged to be offset in the same direction throughout the entire light-emitting device, or they may be arranged so that the center of the light-emitting section 32 and the center of the lens 17 overlap near the center of the light-emitting device and the offset between the center of the light-emitting section 32 and the center of the lens 17 becomes greater toward the outside of the light-emitting device. On the other hand, the center of the light-emitting section 32 and the center of the lens 17 may be arranged so that they overlap near the center of the light-emitting region.

[0127] In this embodiment, the color filter 15 is provided on the planarization layer, but the color filter 15 may be provided on the protective layer 13. For example, the planarization layer may not be provided, and the color filter 15 and the protective layer 13 may be continuous. Alternatively, for example, the color filter 15 and the protective layer 13 may be integrated. The color filter 15 of the light-emitting device may be formed on a support substrate separate from the substrate 8, and then attached to face the protective layer 13.

[0128] The planarizing layer is provided to flatten the unevenness of the upper surface of the protective layer 13. By providing the planarizing layer, the color filters 15 can be formed by a photolithography process in a manner that is precisely aligned with the light-emitting sections 32. Furthermore, as described above, by omitting the planarizing layer and integrating the color filters 15 and the protective layer 13, the color filters 15 can be formed by a photolithography process in a manner that is precisely aligned with the light-emitting sections 32.

[0129] 1, color filters 15r, 15g, and 15b may transmit light of different colors. For example, color filter 15r may transmit red light, color filter 15g may transmit green light, and color filter 15b may transmit blue light. Some or all of the color filters 15 may be omitted. In this case, a different light-emitting layer in organic layer 20 may be formed for each light-emitting element, and the color of light emitted by light-emitting unit 32 may be different, thereby enabling full-color display.

[0130] In this embodiment, the lens 17 is provided on a planarization layer. The planarization layer is provided to flatten the unevenness on the upper surface of the color filter 15. However, the lens 17 may be provided on the color filter 15. In that case, the planarization layer does not have to be provided. Furthermore, the lens 17 and the color filter 15 may be integrated.

[0131] Furthermore, the lens 17 may be provided on the protective layer 13 without the color filter 15 or the planarizing layer being disposed. For example, the lens 17 and the protective layer 13 may be integrated together. When the lens 17 and the protective layer 13 are integrated together, the distance from the lens 17 to the light-emitting section 32 can be made shorter than when the lens 17 is formed on a separate substrate and attached to the protective layer 13 so as to face the substrate. As a result, the solid angle of light incident on the lens 17 from the light-emitting section 32 can be widened, improving the light extraction efficiency.

[0132] By integrating the lens 17 and the protective layer 13, the curved surface 40 of the lens 17 can be aligned with high precision with respect to the light-emitting section 32. Furthermore, for example, by integrating the color filter 15, the lens 17, and the protective layer 13, the light-emitting section 32, the color filter 15, and the lens 17 can be aligned with each other with high precision.

[0133] The stacking order of color filter 15 and lens 17 can be selected as appropriate. In the configuration shown in FIG. 1, color filter 15 is provided on the light-emitting section 32 side of lens 17. In this configuration, light emitted from light-emitting section 32 passes through color filter 15 before entering lens 17. As a result, light that causes a decrease in color purity (light that is emitted from the light-emitting section at a large angle) passes through color filter 15 over a relatively long distance. This makes it possible to further suppress a decrease in color purity when the light-emitting device is observed from an oblique direction.

[0134] Alternatively, a light-emitting device may be fabricated by forming color filter 15 and lens 17 on a support substrate separate from substrate 8 and attaching them to substrate 8 having light-emitting section 32 so that they face each other. Forming color filter 15 and lens 17 separately from organic layer 20 (light-emitting layer) increases the degree of freedom in the processing method (for example, temperature) used to form color filter 15 and lens 17, and also increases the degree of freedom in the design of color filter 15 and lens 17.

[0135] The color filters 15 and the lenses 17 may be formed continuously on one support substrate, or the color filters 15 and the lenses 17 may be formed on separate support substrates. The lenses 17 and the color filters 15 may be bonded to the substrate 8 using a bonding member such as an adhesive. The bonding member may be disposed on the planarizing layer, or may be disposed on the protective layer 13 if no planarizing layer is disposed.

[0136] The lens 17 may be formed on a support substrate separate from the substrate 8 and attached to the substrate 8 having the light-emitting portion 32 so as to face the substrate 8. In this case, the lens 17 may be fixed to the substrate 8 at the end of the light-emitting device with a bonding member such as an adhesive so as to provide a space between the lens 17 and the protective layer 13 (or the color filter 15). In this case, the space may be filled with a resin. The refractive index of the resin may be smaller than the refractive index n of the lens 17.

[0137] Here, application examples in which the light-emitting device of this embodiment is applied to a display device, a photoelectric conversion device, an electronic device, a lighting device, a mobile object, a wearable device, and an exposure light source of an electrophotographic image forming apparatus will be described with reference to Figures 10 to 17.

[0138] FIG. 10 is a schematic diagram illustrating an example of a display device using the light-emitting device of this embodiment. The display device 1000 may include a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. The touch panel 1003 and the display panel 1005 are connected to flexible printed circuits FPCs 1002 and 1004. An active element such as a transistor is disposed on the circuit board 1007. The battery 1008 may not be disposed if the display device 1000 is not a portable device, and even if it is a portable device, it does not need to be disposed in this position. A light-emitting device can be applied to the display panel 1005. The light-emitting device functioning as the display panel 1005 is connected to and operates with active elements such as transistors disposed on the circuit board 1007.

[0139] The display device 1000 shown in Fig. 10 may be used as a display unit of a photoelectric conversion device (image capture device) having an optical unit with multiple lenses and an image capture element that receives light that has passed through the optical unit and photoelectrically converts it into an electrical signal. The photoelectric conversion device may have a display unit that displays information acquired by the image capture element. The display unit may be a display unit exposed to the outside of the photoelectric conversion device or a display unit located within a viewfinder. The photoelectric conversion device may be a digital camera or a digital video camera.

[0140] FIG. 11 is a schematic diagram illustrating an example of a photoelectric conversion device using the light-emitting device of this embodiment. The photoelectric conversion device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The photoelectric conversion device 1100 may also be called an imaging device. The light-emitting device of this embodiment can be applied to the viewfinder 1101 or the rear display 1102, which are display units. In this case, the light-emitting device may display not only an image to be captured, but also environmental information, imaging instructions, and the like. The environmental information may include the intensity of external light, the direction of external light, the speed at which the subject is moving, the possibility that the subject will be blocked by an obstruction, and the like.

[0141] Since the timing suitable for capturing an image is often very short, it is better to display information as soon as possible. Therefore, a light-emitting device equipped with organic light-emitting elements using organic light-emitting materials such as organic EL elements may be used for the viewfinder 1101 and the rear display 1102. This is because organic light-emitting materials have a fast response speed. Light-emitting devices using organic light-emitting materials are more suitable than liquid crystal display devices for these devices, which require high display speed.

[0142] The photoelectric conversion device 1100 has an optical section (not shown). The optical section has multiple lenses, which form an image on a photoelectric conversion element (not shown) housed in a housing 1104 that receives light that has passed through the optical section. The focus of the multiple lenses can be adjusted by adjusting their relative positions. This operation can also be performed automatically.

[0143] The light-emitting device may be applied to a display unit of an electronic device. In this case, the light-emitting device may have both a display function and an operation function. Examples of the portable terminal include a mobile phone such as a smartphone, a tablet, and a head-mounted display.

[0144] FIG. 12 is a schematic diagram showing an example of an electronic device using the light-emitting device of this embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The housing 1203 may be provided with a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type reaction unit. The operation unit 1202 may be a biometric recognition unit that recognizes a fingerprint to perform operations such as unlocking. A portable device having a communication unit can also be called a communication device. The light-emitting device of this embodiment can be applied to the display unit 1201.

[0145] 13(a) and 13(b) are schematic diagrams illustrating an example of a display device using the light-emitting device of this embodiment. FIG. 13(a) illustrates a display device such as a television monitor or a PC monitor. The display device 1300 has a frame 1301 and a display unit 1302. The light-emitting device of this embodiment can be applied to the display unit 1302. The display device 1300 may have a base 1303 that supports the frame 1301 and the display unit 1302. The base 1303 is not limited to the form shown in FIG. 13(a). For example, the bottom edge of the frame 1301 may also serve as the base 1303. The frame 1301 and the display unit 1302 may be curved. The radius of curvature may be 5000 mm or more and 6000 mm or less.

[0146] FIG. 13(b) is a schematic diagram illustrating another example of a display device using the light-emitting device of this embodiment. The display device 1310 of FIG. 13(b) is configured to be bendable and is a so-called foldable display device. The display device 1310 has a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. The light-emitting device of this embodiment can be applied to the first display unit 1311 and the second display unit 1312. The first display unit 1311 and the second display unit 1312 may be a single display unit without any joints. The first display unit 1311 and the second display unit 1312 can be separated by the bending point. The first display unit 1311 and the second display unit 1312 may display different images, or the first display unit and the second display unit may display a single image.

[0147] FIG. 14 is a schematic diagram illustrating an example of a lighting device using the light-emitting device of this embodiment. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusion unit 1405. The light-emitting device of this embodiment can be applied to the light source 1402. The optical film 1404 may be a filter that improves the color rendering of the light source. The light diffusion unit 1405 can effectively diffuse light from the light source, such as for lighting up, and deliver the light over a wide area. If necessary, a cover may be provided on the outermost part. The lighting device 1400 may include both the optical film 1404 and the light diffusion unit 1405, or only one of them.

[0148] The lighting device 1400 is, for example, a device that illuminates a room. The lighting device 1400 may emit white, daylight white, or any other color from blue to red. It may have a dimming circuit that adjusts the light intensity. The lighting device 1400 may have a power supply circuit connected to a light-emitting device that functions as the light source 1402. The power supply circuit is a circuit that converts AC voltage into DC voltage. White has a color temperature of 4200K, and daylight white has a color temperature of 5000K. The lighting device 1400 may also have a color filter. The lighting device 1400 may also have a heat sink. The heat sink dissipates heat from within the device to the outside, and examples of the heat sink include metal with a high specific heat, liquid silicon, etc.

[0149] FIG. 15 is a schematic diagram of an automobile having a tail lamp, which is an example of a vehicle lamp using the light-emitting device of this embodiment. The automobile 1500 may have a tail lamp 1501, and may be configured to turn on the tail lamp 1501 when braking or the like is performed. The light-emitting device of this embodiment may be used as a headlamp as a vehicle lamp. An automobile is an example of a mobile body, and the mobile body may be a ship, a drone, an aircraft, a railcar, an industrial robot, or the like. The mobile body may have a body and a lamp provided thereon. The lamp may indicate the current location of the body.

[0150] The light emitting device of this embodiment can be applied to a tail lamp 1501. The tail lamp 1501 may have a protective member that protects the light emitting device functioning as the tail lamp 1501. The protective member may be made of any material as long as it has a certain degree of strength and is transparent, but may be made of polycarbonate or the like. The protective member may also be made by mixing a furandicarboxylic acid derivative, an acrylonitrile derivative, or the like with polycarbonate.

[0151] The automobile 1500 may have a body 1503 and a window 1502 attached thereto. The window may be a window for checking the front and rear of the automobile, or may be a transparent display such as a head-up display. The light-emitting device of this embodiment may be used in the transparent display. In this case, the constituent materials of the electrodes and the like of the light-emitting device are made of transparent materials.

[0152] 16(a) and 16(b), a further application example of the light emitting device of this embodiment will be described. The light emitting device can be applied to systems that can be worn as wearable devices, such as smart glasses, head-mounted displays (HMDs), and smart contact lenses. An image capturing and displaying device used in such an application example has an image capturing device capable of photoelectrically converting visible light and a light emitting device capable of emitting visible light.

[0153] 16(a) illustrates glasses 1600 (smart glasses) according to one application example. An imaging device 1602 such as a CMOS sensor or SPAD is provided on the front side of a lens 1601 of the glasses 1600. In addition, a light-emitting device according to this embodiment is provided on the back side of the lens 1601.

[0154] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power source that supplies power to the image capture device 1602 and the light emitting device according to each embodiment. The control device 1603 also controls the operations of the image capture device 1602 and the light emitting device. The lens 1601 is formed with an optical system for focusing light onto the image capture device 1602.

[0155] FIG. 16(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 include a control device 1612, which is equipped with an imaging device equivalent to the imaging device 1602 and a light-emitting device. A lens 1611 includes an optical system for projecting light emitted from the imaging device and the light-emitting device within the control device 1612, and an image is projected onto the lens 1611. The control device 1612 functions as a power source for supplying power to the imaging device and the light-emitting device and controls the operation of the imaging device and the light-emitting device. The control device 1612 may also include a gaze detection unit for detecting the gaze of the wearer. Infrared light may be used for gaze detection. The infrared light-emitting unit emits infrared light toward the eyeball of a user gazing at a displayed image. An imaging unit with a light-receiving element detects the reflected light of the emitted infrared light from the eyeball, thereby obtaining an image of the eyeball. A reduction unit for reducing light from the infrared light-emitting unit to the display unit in a planar view reduces degradation of image quality.

[0156] The gaze of the user relative to the displayed image is detected from an image of the eyeball obtained by capturing infrared light. Any known method can be used for gaze detection using the image of the eyeball. As an example, a gaze detection method based on the Purkinje image formed by reflection of irradiated light on the cornea can be used.

[0157] More specifically, gaze detection processing is performed based on the pupil-corneal reflex method, which calculates a gaze vector representing the direction (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the captured image of the eyeball, thereby detecting the user's gaze.

[0158] A light emitting device according to an embodiment of the present disclosure may include an imaging device having a light receiving element, and may control a display image based on user line of sight information from the imaging device.

[0159] Specifically, the light-emitting device determines a first field of view area where the user gazes and a second field of view area other than the first field of view area based on the line-of-sight information. The first field of view area and the second field of view area may be determined by a control device of the light-emitting device, or may be determined by an external control device and received. In the display area of ​​the light-emitting device, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area may be lower than that of the first field of view area.

[0160] The display area includes a first display area and a second display area different from the first display area, and a high-priority area is determined from the first display area and the second display area based on line-of-sight information. The first display area and the second display area may be determined by a control device of the light-emitting device, or may be determined by an external control device and received. The resolution of the high-priority area may be controlled to be higher than the resolution of areas other than the high-priority area. In other words, the resolution of an area with a relatively low priority may be lowered.

[0161] Note that AI may be used to determine the first field of view area and areas with high priority. The AI ​​may be a model configured to estimate the angle of gaze and the distance to an object in the line of sight from the image of the eyeball, using as training data an image of the eyeball and the direction in which the eyeball in the image was actually looking. The AI ​​program may be included in the light-emitting device, the imaging device, or an external device. If included in an external device, it is transmitted to the light-emitting device via communication.

[0162] When display control is performed based on visual recognition detection, the smart glasses can be preferably applied to smart glasses that further include an imaging device for capturing images of the outside world. The smart glasses can display captured external information in real time.

[0163] Fig. 17 shows an image forming apparatus according to one embodiment of the present invention. Fig. 17(a) is a schematic diagram of an image forming apparatus 48 according to one embodiment of the present invention. The image forming apparatus has a photoconductor, an exposure light source, a developing unit, a charging unit, a transfer unit, a transport roller, and a fixing unit.

[0164] Light 51 is irradiated from an exposure light source 50, and an electrostatic latent image is formed on the surface of the photosensitive member 49. This exposure light source has an organic light-emitting element according to the present invention. A developing unit 53 has toner and the like. A charging unit 52 charges the photosensitive member. A transfer device 54 transfers the developed image to a recording medium 56. A transport unit 55 transports the recording medium 56. The recording medium 56 is, for example, paper. A fixing unit 57 fixes the image formed on the recording medium.

[0165] 17(b) and 17(c) are schematic diagrams showing an exposure light source 58 in which a plurality of light-emitting units 59 are arranged on a long substrate. 61 is a direction parallel to the axis of the photoconductor, and represents the column direction in which the organic light-emitting elements are arranged. This column direction is the same as the axis direction about which the photoconductor 60 rotates. This direction can also be called the long axis direction of the photoconductor.

[0166] Figure 17(b) shows a configuration in which the light-emitting units are arranged along the longitudinal axis of the photoconductor. Figure 17(c) shows a different configuration from (b), in which the light-emitting units are arranged alternately in the column direction in the first and second columns. The first and second columns are arranged at different positions in the row direction.

[0167] The first column has a plurality of light-emitting units arranged at intervals. The second column has light-emitting units at positions corresponding to the intervals between the light-emitting units in the first column. That is, the plurality of light-emitting units are also arranged at intervals in the row direction.

[0168] The arrangement in FIG. 17(c) can also be described as a grid arrangement, a houndstooth arrangement, or a checkerboard pattern.

[0169] As described above, by using a device using the organic light-emitting element according to this embodiment, it is possible to provide a stable display with good image quality even over a long period of time.

[0170] An embodiment of the light emitting device will be described below.

[0171] (First Example) First, aluminum was formed on the substrate 8 and then patterned into a cone shape using photolithography and etching to form a plurality of reflective layers 9 as first electrodes. Next, silicon oxide was formed to a thickness of 65 nm as a material film for the insulating layer 12 so as to cover each of the plurality of reflective layers 9. An opening was formed in the center of each of the plurality of reflective layers 9 in the material film to expose the reflective layer 9, thereby forming the insulating layer 12. The openings exposing the reflective layer 9 were circular in shape with a radius of 2.0 μm.

[0172] As described above, the openings formed in the insulating layer 12 ultimately correspond to the light-emitting sections 32. That is, in orthogonal projection onto the main surface P1 of the substrate 8, the size and shape of the openings can match the size and shape of the light-emitting sections 32. The inclination angle of the reflective layer 9 at the edge of the opening with respect to the main surface P1 of the substrate 8 was set to 10 degrees. The shape of the reflective layer 9 was set to be the same throughout the display area within the range of manufacturing tolerance.

[0173] After forming the insulating layer 12, an organic layer 20 was formed on the multiple reflective layers 9 and the insulating layer 12. Specifically, compound 1 (details will be described later; the same applies to other compounds) was formed to a thickness of 3 nm as a hole injection layer. Compound 2 was formed to a thickness of 15 nm as a hole transport layer on the hole injection layer. Compound 3 was formed to a thickness of 10 nm as an electron blocking layer on the hole transport layer. Next, a first light-emitting layer was formed to a thickness of 10 nm so that compound 4 as a host material was 97% by weight and compound 5 as a light-emitting dopant was 3% by weight.

[0174] Next, a second light-emitting layer was formed to a thickness of 10 nm, with Compound 4 as the host material at a weight ratio of 98% and Compounds 6 and 7 as the light-emitting dopants at a weight ratio of 1% each. Next, Compound 8 was formed to a thickness of 110 nm as an electron-transporting layer on the second light-emitting layer. Next, lithium fluoride was formed to a thickness of 1 nm as an electron-injecting layer on the electron-transporting layer.

[0175] [ka]

[0176] After forming the organic layer 20, a 10-nm-thick MgAg alloy was formed on the organic layer 20 as the conductive layer 11 serving as the second electrode. The ratio of Mg to Ag was 1:1. Then, a 2.0-μm-thick SiN film with a refractive index of 1.97 was formed on the conductive layer 11 serving as the second electrode using a CVD method as the protective layer 13. Next, a 0.2-μm-thick planarization layer with a refractive index of 1.55 was formed on the protective layer 13 using a spin coating method at a position overlapping the first position.

[0177] Next, color filters 15 with a refractive index of 1.65 were formed on the planarization layer to a thickness of 1.6 μm. Color filters 15r transmit red light, color filters 15g transmit green light, and color filters 15b transmit blue light. After the color filters 15 were formed, a planarization layer with a refractive index of 1.55 was formed on the color filters 15 to a thickness of 0.2 μm using a spin coating method.

[0178] Next, a lens 17 with a refractive index of 1.52 was formed on the planarization layer using an exposure process and a development process. The curved surface 40 of the lens 17 was a part of a spherical surface. The distance h, which is the difference in height between the vertex 41 and the end 42 of the curved surface 40 in the normal direction to the main surface of the substrate 8, was 2.3 μm, and the distance r, between the vertex 41 and the end of the curved surface 40 in the orthogonal projection onto the main surface of the substrate 8, was 3.4 μm. The lens 17 was arranged so that the vertex 41 and the center of the light-emitting portion 31 overlapped at the center of the light-emitting region, and so that the vertex 41 and the center of the light-emitting portion 31 were offset by 1.5 μm at the outermost periphery of the light-emitting region.

[0179] In the light-emitting element located on the periphery of the light-emitting region of the light-emitting device described above, the tilt angle θ1 at the first position P1 is 10 degrees, the distance V1 between the first position of the tilted portion and the apex of the lens in the direction parallel to the main surface of the substrate is 2.5 μm, and the distance V1 in the vertical direction is approximately 6.3 μm. Therefore, the relationship tan θ1≦H1 / V1 is satisfied, and the line passing through the apex of the lens and perpendicular to the line connecting both ends of the lens intersects with the normal to the reflective layer at the first position closer to the light extraction side than the apex of the lens.

[0180] As a result, the fabricated light emitting device was able to increase the amount of extracted light in a direction tilted 35 degrees from the normal to the substrate in the light emitting elements on the periphery of the light emitting region.

[0181] (Example 2) (Example of changing the orientation of the reflective electrode within the plane) Next, a light emitting device of Example 2 will be described. In Example 1, the reflective layer 9 serving as the first electrode had the same shape throughout the entire light emitting region, but in this example, the reflective layer 9 serving as the first electrode had different shapes depending on the position within the light emitting region. Specifically, the light emitting element at the center of the light emitting region did not have an inclined portion, while the light emitting element at the outermost periphery of the light emitting region had a flat plate-like shape with an inclination angle of 10 degrees. The rest of the configuration was the same as in Example 1.

[0182] As in Example 1, the fabricated light-emitting device satisfies the relationship tanθ1≦H1 / V1, and a line passing through the vertex of the lens and perpendicular to a line passing through both ends of the lens intersects with the normal to the reflective layer at the first position closer to the light extraction side than the vertex of the lens.

[0183] As a result, the fabricated light-emitting device was able to increase the amount of extracted light in a direction tilted 35 degrees from the normal to the substrate in the light-emitting elements on the periphery of the light-emitting region, and also increased the amount of extracted light in the front direction in the pixel at the center of the light-emitting region.

[0184] The present disclosure includes, for example, the following configurations.

[0185] (Configuration 1) A substrate; a first light-emitting unit including a reflective layer disposed on a main surface of the substrate, an organic layer disposed on the reflective layer, and a conductive layer disposed on the organic layer; a first lens arranged to overlap at least a portion of the first light-emitting portion in a plan view from a direction perpendicular to the main surface of the substrate; the first lens has a positive power and a convex shape directed in a direction away from the substrate; In a cross section passing through the vertex of the convex shape of the first lens and perpendicular to the main surface, the midpoint of a line segment connecting one end and the other end of the first light-emitting section is defined as the center of the first light-emitting section, In the plan view, a vertex of the first lens is spaced a first distance from the center of the first light-emitting portion, In the cross section, the reflective layer has an inclined portion inclined with respect to the main surface, a first position is a point in the inclined portion of the reflective layer that is farthest from the vertex of the first lens in a direction parallel to the main surface; a second line extending in a direction perpendicular to a first line passing through both ends of the first lens and passing through the vertex of the first lens intersects at one point with a normal to the reflective layer at the first position of the inclined portion; The light emitting device wherein the one point coincides with the vertex of the first lens or is located closer to the light extraction side than the vertex of the first lens.

[0186] (Configuration 2) A light-emitting device of configuration 1, characterized in that in the cross section, the intersection of the normal and the second straight line at a position other than the first position in the inclined portion of the reflective layer coincides with the vertex of the first lens or is located on the light extraction side of the vertex of the first lens.

[0187] (Configuration 3) In the cross section, When the distance from the vertex of the first lens to the first position in a direction parallel to the principal surface is a distance H1 and the distance in a vertical direction is a distance V1, the inclination angle θ1 at the first position is tanθ1≦H1 / V1 The light-emitting device of Configuration 1 or 2, characterized by satisfying the following relationship.

[0188] (Configuration 4) A medium layer is disposed between the conductive layer and the first lens, in contact with the conductive layer. When the refractive index of the medium layer is n1, The inclination angle θ1 at the first position is sinθ1 < 1 / n1 The light-emitting device of any one of Configurations 1 to 3, characterized by satisfying the following relationship.

[0189] (Configuration 5) When the refractive index of the first lens is n2, At the first position, H1 < V1 / (n2 2 -1) 1 / 2 The light-emitting device of Configuration 3, characterized by satisfying the following relationship.

[0190] (Configuration 6) In the cross-section, The point where the inclination angle α of the lens formed by the curved surface of the first lens and the main surface is the maximum is defined as the second position. The distance from the vertex of the first lens to the second position in the direction parallel to the main surface of the substrate is r. The distance from the first position to the second position in the direction perpendicular to the main surface of the substrate is V2. When the distance from the center of the first light-emitting portion to the end of the first light-emitting portion in the direction parallel to the main surface of the substrate is H2, In the light ray that passes through the second position and exits in the direction perpendicular to the main surface of the substrate, when the distance from the second position in the direction parallel to the main surface of the substrate at a position V2 away from the second position in the direction perpendicular to the main surface of the substrate is A, A < H2 The light-emitting device of any one of Configurations 1 to 5, characterized by satisfying the following relationship.

[0191] (Configuration 7) In the cross section, when a point where the inclination angle α of the lens formed by the curved surface of the first lens and the main surface of the substrate is maximum is defined as a second position, 7. The light emitting device of any one of configurations 1 to 6, wherein the tilt angle α in the second position is smaller than 90°.

[0192] (Configuration 8) The refractive index of the medium layer is n1, When the refractive index of the first lens is n2, The light-emitting device according to configuration 4, wherein the relationship n2≦n1 is satisfied.

[0193] (Configuration 9) The light-emitting device of Structure 4 or 8, further comprising a color filter disposed between the medium layer and the first lens.

[0194] (Configuration 10) When the refractive index of the first lens is n2 and the refractive index of the color filter is n3, 10. The light emitting device of any one of configurations 4, 8, and 9, wherein the relationship n2≦n3 is satisfied.

[0195] (Configuration 11) 8. The light-emitting device of any one of structures 1 to 7, wherein when the refractive index of the first lens is n2, no layer having a refractive index smaller than n2 is disposed between the conductive layer and the first lens.

[0196] (Configuration 12) a second light-emitting unit including the substrate, a third reflective layer disposed on the main surface of the substrate, an organic layer disposed on the third reflective layer, and a fourth reflective layer disposed on the organic layer; and a second lens disposed so as to overlap with at least a portion of the second light-emitting unit in the planar view, the second lens has a positive power; In the plan view, the vertex of the second lens is spaced a second distance from the center of the second light-emitting portion, 12. The light emitting device of any one of configurations 1 to 11, wherein the second distance is smaller than the first distance.

[0197] (Configuration 13) 13. The light emitting device of configuration 12, wherein the distance between the center of the first light emitting portion and the edge of the substrate is smaller than the distance between the center of the second light emitting portion and the edge of the substrate.

[0198] (Configuration 14) a plurality of sets of a light emitting unit and a lens, including a set of the first lens and the first light emitting unit, and a set of the second lens and the second light emitting unit; In the plan view, The distance between the center of the area where the plurality of sets are arranged and the center of the first light-emitting unit is 14. The light emitting device of structure 12 or 13, wherein the distance is greater than the distance between the center of the area in which the plurality of sets are arranged and the center of the second light emitting section.

[0199] (Configuration 15) the third reflective layer has an inclined portion that forms a positive inclination angle with the main surface of the substrate in a direction toward the vertex of the second lens, a point on the inclined portion of the third reflective layer that is the longest distance from the vertex of the second lens in a direction parallel to the main surface is defined as a third position; When the distance from the vertex of the second lens to the third position in a direction parallel to the principal surface is H2 and the distance in a direction perpendicular to the principal surface is V2, the inclination angle θ2 at the third position is V2·tanθ2 / H2>V1·tanθ1 / H1 15. The light emitting device according to any one of configurations 12 to 14, wherein the following relationship is satisfied:

[0200] (Configuration 16) 16. The light-emitting device of any one of configurations 13 to 15, wherein the reflective layer and the third reflective layer have substantially the same shape.

[0201] (Configuration 17) the third reflective layer has an inclined portion that forms a positive inclination angle with the main surface of the substrate in a direction toward the vertex of the second lens, a point on the inclined portion of the third reflective layer that is the longest distance from the vertex of the second lens in a direction parallel to the main surface is defined as a third position; When the distance from the vertex of the second lens to the third position in the parallel direction is a distance L3 and the distance in the direction perpendicular to the main surface is a distance H2, the inclination angle θ2 at the third position is V2·tanθ2 / H2≦V1·tanθ1 / H1 17. The light emitting device according to any one of configurations 13 to 16, wherein the following relationship is satisfied:

[0202] (Configuration 18) 18. The light emitting device of any one of Structures 13 to 17, wherein at least a portion of the third reflective layer is parallel to the main surface of the substrate.

[0203] (Configuration 19) 19. A display device comprising: a light-emitting device according to any one of configurations 1 to 18; and an active element connected to the light-emitting device.

[0204] (Configuration 20) an optical unit having a plurality of lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays an image; 19. A photoelectric conversion device, wherein the display unit displays an image captured by the imaging element, and the photoelectric conversion device comprises a light-emitting device according to any one of configurations 1 to 18.

[0205] (Configuration 21) A display unit is provided in the housing, and a communication unit is provided in the housing and communicates with an external device. 19. An electronic device, wherein the display unit comprises the light-emitting device according to any one of configurations 1 to 18.

[0206] (Configuration 22) a photosensitive member and an exposure light source that exposes the photosensitive member; 19. An image forming apparatus, wherein the exposure light source comprises the light emitting device according to any one of the first to eighteenth aspects. [Explanation of symbols]

[0207] 8 PCB 9 Reflective layer 11 Conductive layer 17 Lenses 20 organic layer 32 Light-emitting part 40 curved surface 41 Vertex 42 End 43 End S1 main surface

Claims

1. A substrate; a first light-emitting unit including a reflective layer disposed on a main surface of the substrate, an organic layer disposed on the reflective layer, and a conductive layer disposed on the organic layer; a first lens arranged to overlap at least a portion of the first light-emitting portion in a plan view from a direction perpendicular to the main surface of the substrate; the first lens has a positive power and a convex shape facing away from the substrate; In a cross section passing through the vertex of the convex shape of the first lens and perpendicular to the main surface, the midpoint of a line segment connecting one end and the other end of the first light-emitting section is defined as the center of the first light-emitting section, In the plan view, a vertex of the first lens is spaced a first distance from the center of the first light-emitting portion, In the cross section, the reflective layer has an inclined portion inclined with respect to the main surface, a first position is a point in the inclined portion of the reflective layer that is farthest from the vertex of the first lens in a direction parallel to the main surface; a second line extending in a direction perpendicular to a first line passing through both ends of the first lens and passing through the vertex of the first lens intersects at one point with a normal to the reflective layer at the first position of the inclined portion; The light emitting device wherein the one point coincides with the vertex of the first lens or is located closer to the light extraction side than the vertex of the first lens.

2. 2. The light-emitting device according to claim 1, wherein, in the cross section, the intersection of the normal and the second straight line at a position other than the first position in the inclined portion of the reflective layer coincides with the vertex of the first lens or is located closer to the light extraction side than the vertex of the first lens.

3. In the cross section, The distance from the vertex of the first lens to the first position in a direction parallel to the principal surface is defined as a distance H １ , the vertical distance is the distance V １ When the tilt angle θ １ but tanθ １ ≦H １ / V １ 2. The light emitting device according to claim 1, wherein the following relationship is satisfied:

4. a medium layer is disposed in contact with the conductive layer between the conductive layer and the first lens; The refractive index of the medium layer is n １ When I said, The tilt angle θ at the first position １ but sinθ １ <1 / n １ 2. The light emitting device according to claim 1, wherein the following relationship is satisfied:

5. The refractive index of the first lens is n ２ When I said, In the first position, H １ <V １ / (n ２ ２ -1) １／２ 4. The light emitting device according to claim 3, wherein the following relationship is satisfied:

6. In the cross section, a point where the inclination angle α of the lens formed by the curved surface of the first lens and the main surface of the reflective layer is maximum is defined as a second position; a distance from the vertex of the first lens to the second position in a direction parallel to the main surface of the substrate is defined as r; The distance from the first position to the second position in the direction perpendicular to the main surface of the substrate is defined as V ２ year, The distance from the center of the first light-emitting portion to the edge of the first light-emitting portion in the direction parallel to the main surface of the substrate is H ２ In this case, In a light ray that passes through the second position and is emitted in a direction perpendicular to the main surface of the substrate, a distance V ２ When the distance from the second position to the distant position in a direction parallel to the main surface of the substrate is A, A<H ２ 2. The light emitting device according to claim 1, wherein the following relationship is satisfied:

7. In the cross section, when a point where an inclination angle α of the lens formed by the curved surface of the first lens and the main surface of the substrate is maximum is defined as a second position, 2. The light emitting device according to claim 1, wherein the tilt angle α at the second position is smaller than 90°.

8. The refractive index of the medium layer is n １ As, The refractive index of the first lens is n ２ When I said, n ２ ≦n １ 5. The light emitting device according to claim 4, wherein the following relationship is satisfied:

9. 5. The light emitting device according to claim 4, further comprising a color filter disposed between the medium layer and the first lens.

10. The refractive index of the first lens is n ２ and the refractive index of the color filter is n ３ When I said, n ２ ≦n ３ 10. The light emitting device according to claim 9, wherein the following relationship is satisfied:

11. The refractive index of the first lens is n ２ When the refractive index is n ２ 2. The light-emitting device according to claim 1, wherein no layer smaller than 100 nm is disposed.

12. a second light-emitting unit including the substrate, a third reflective layer disposed on the main surface of the substrate, an organic layer disposed on the third reflective layer, and a fourth reflective layer disposed on the organic layer; and a second lens disposed so as to overlap at least a portion of the second light-emitting unit in the planar view, the second lens has a positive power; In the plan view, a vertex of the second lens is spaced a second distance from a center of the second light-emitting portion, The light emitting device according to claim 1 , wherein the second distance is smaller than the first distance.

13. The light emitting device according to claim 12 , wherein a distance between a center of the first light emitting portion and an edge of the substrate is smaller than a distance between a center of the second light emitting portion and the edge of the substrate.

14. a plurality of sets of a light emitting unit and a lens, including a set of the first lens and the first light emitting unit, and a set of the second lens and the second light emitting unit; In the plan view, The distance between the center of the area in which the plurality of sets are arranged and the center of the first light-emitting unit is The light emitting device according to claim 12 , wherein the distance is greater than the distance between the center of the region in which the plurality of sets are arranged and the center of the second light emitting portion.

15. the third reflective layer has an inclined portion that forms a positive inclination angle with the main surface of the substrate in a direction toward the vertex of the second lens, a point on the inclined portion of the third reflective layer that is the longest distance from the vertex of the second lens in a direction parallel to the main surface is defined as a third position; The distance from the vertex of the second lens to the third position in a direction parallel to the principal surface is defined as H ２ , the distance in the direction perpendicular to the main surface is V ２ When the tilt angle θ ２ but V ２ ・tanθ ２ / H ２ >V １ ・tanθ １ / H １ 14. The light emitting device according to claim 13, wherein the following relationship is satisfied:

16. The light emitting device according to claim 13 , wherein the reflective layer and the third reflective layer have substantially the same shape.

17. the third reflective layer has an inclined portion that forms a positive inclination angle with the main surface of the substrate in a direction toward the vertex of the second lens, a point on the inclined portion of the third reflective layer that is the longest distance from the vertex of the second lens in a direction parallel to the main surface is defined as a third position; The distance from the vertex of the second lens to the third position in the parallel direction is a distance L3, and the distance in the direction perpendicular to the principal surface is a distance H ２ When the tilt angle θ ２ but V ２ ・tanθ ２ / H ２ ≦V １ ・tanθ １ / H １ 14. The light emitting device according to claim 13, wherein the following relationship is satisfied:

18. 14. The light emitting device according to claim 13, wherein at least a portion of the third reflective layer is parallel to the main surface of the substrate.

19. A display device comprising: a light-emitting device according to claim 1; and an active element connected to the light-emitting device.

20. an optical unit having a plurality of lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays an image; A photoelectric conversion device, wherein the display section displays an image captured by the imaging element, and the photoelectric conversion device comprises the light-emitting device according to claim 1 .

21. A display unit is provided in the housing, and a communication unit is provided in the housing and communicates with an external device.

19. An electronic device, wherein the display unit comprises the light-emitting device according to claim 1.

22. a photosensitive member and an exposure light source that exposes the photosensitive member; 19. An image forming apparatus, comprising: an exposure light source comprising the light emitting device according to claim 1.

Images