Light emitting device, image forming apparatus, display, photoelectric conversion device, and electronic apparatus

Abstract

To provide a technique advantageous for improving light take-out efficiency.SOLUTION: A light emitting device has a plurality of luminous elements arranged on a principal surface of a substrate. The plurality of luminous elements each include a light emitting part and a lens. A surface of the lens has convex swellings extending continuously in a direction along the principal surface, and includes convex parts having a positive power and concave parts each surrounded by the convex parts.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a light-emitting device, an image forming device, a display device, a photoelectric conversion device, and an electronic device.

Background Art

[0002] Patent Document 1 shows that in order to improve the light extraction efficiency in a light-emitting device, a lens is disposed on the light-emitting portion, and the shape of the lens and the distance between the lens and the light-emitting portion are adjusted.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In order to improve the performance of the light-emitting device, it is necessary to extract the light emitted from the light-emitting portion more efficiently.

[0005] An object of the present invention is to provide a technique advantageous for improving the light extraction efficiency.

Means for Solving the Problems

[0006] In view of the above problems, a light-emitting device according to an embodiment of the present invention is a light-emitting device in which a plurality of light-emitting elements are arranged on a main surface of a substrate, each of the plurality of light-emitting elements including a light-emitting portion and a lens, and a surface of the lens having a convex bulge continuously extending in a direction along the main surface, and including a convex portion having a positive power and a concave portion surrounded by the convex portion.

Effects of the Invention

[0007] According to the present invention, it is possible to provide a technique advantageous for improving the light extraction efficiency.

Brief Description of the Drawings

[0008]

Figure 1

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Figure 18

Modes for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] With reference to FIGS. 1 to 10, a light-emitting device according to an embodiment of the present disclosure will be described. FIG. 1 is a cross-sectional view showing a configuration example of a lens 117 arranged in the light-emitting device 100 of the present embodiment. FIG. 2 is a cross-sectional view showing a configuration example of a lens 117' arranged in a light-emitting device 100' of a comparative example. In the light-emitting device 100, a plurality of light-emitting elements 101 are arranged on the main surface 152 of the substrate 108. Each of the plurality of light-emitting elements 101 includes a light-emitting portion 132 and a lens 117. In the example shown in FIG. 1, as the light-emitting portion 132, an organic light-emitting element including an electrode 109 (which may also be called a lower electrode or the like), an organic layer 120 including a light-emitting layer, and an electrode 111 (which may also be called an upper electrode or the like) is shown. However, the present invention is not limited thereto. For example, as the light-emitting portion 132, a light-emitting element including an inorganic light-emitting material or quantum dots may be used, or a light-emitting diode or the like may be used. For example, a so-called micro LED may be used as the light-emitting portion 132. Details of the light-emitting element 101 and the insulating layer 112, protective layer 113, planarization layer 114, color filter 115, planarization layer 116, etc. included in the light-emitting element 101 will be described later.

[0011] The lens 117 may also be called a microlens or the like. The surface 151 of the lens 117 (which may also be called the upper surface or the like) has a convex portion 140 with a convex shape in a direction away from the main surface 152 of the substrate 108. The convex portion 140 is a portion where a convex bulge continuously extends in a direction along the main surface 152 of the substrate 108 on the surface 151 of the lens 117. The light radiated in the outer direction (the direction away from the center of the light emitting portion 132 in the orthographic projection onto the main surface 152 of the substrate 108) from the light emitting portion 132 is converted into parallel light (collimated light) by refraction at the convex portion 140 of the lens 117 and can be extracted in a direction perpendicular to the main surface 152 of the substrate 108 (the front direction). That is, the lens 117 can function as a collimator. The convex portion 140 of the lens 117 may have a condensing property. The convex portion 140 of the lens 117 may have a positive power to convert the light radiated from the light emitting portion 132 into parallel light or converging light.

[0012] The convex portion 140 includes a top portion 141. The top portion 141 of the convex portion 140 may be the portion of the surface 151 of the lens 117 that is farthest from the main surface 152 of the substrate 108. Also, the top portion 141 may be a set of points where the distance from the main surface 152 of the substrate 108 is maximized. Further, for example, the top portion 141 may also be a portion of the convex portion 140 where its tangent is parallel to the main surface 152 of the substrate 108. FIGS. 1 and 2 show a cross section passing through the top portion 141 of the convex portion 140 constituting the surface 151 of the lens 117 and parallel to the normal line of the main surface 152 of the substrate 108.

[0013] In the present embodiment, in the orthographic projection onto the main surface 152 of the substrate 108, the top portion 141 forms a closed loop. In the configuration example shown in FIG. 1, the top portion 141 forms, for example, a circle. In the orthographic projection onto the main surface 152 of the substrate 108, the top portion 141 is not limited to being circular and may be, for example, square, rectangular, hexagonal, or the like. On the other hand, in the comparative example of FIG. 2, the top portion 141 does not form a closed loop and is a single point.

[0014] When the outer edges 145 of the lenses 117 are formed independently of each other for the lenses 117 arranged for the light-emitting elements 101 adjacent to each other, they are the outermost peripheral portions of the lenses 117. Also, when the lenses 117 arranged for the light-emitting elements 101 adjacent to each other are formed continuously, between the light-emitting elements 101 adjacent to each other, the outer edge 145 of the lens is a portion where the tangent line of the surface 151 of the lens 117 is parallel to the main surface 152 of the substrate 108. For example, the outer edge 145 of the lens 117 may be a set of points where the distance from the main surface 152 of the substrate 108 to the surface 151 of the lens 117 is minimized.

[0015] There may be a convex-shaped region on the side opposite to the top 141 around the outer edge 145 of the lens 117. In the example shown in FIG. 1, a recess 144 is arranged around the outer edge 145 of the lens 117. The outer edge 145 of the lens 117 may be the portion closest to the main surface 152 of the substrate 108 among the recesses 144. The boundary between the convex portion 140 and the recess 144 may be a set of inflection points where the surface 151 of the lens 117 changes from a convex shape to a concave shape. Also, for example, the boundary between the convex portion 140 and the recess 144 may be a set of positions (points) where the angle (tilt angle θ) of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 is maximized between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117. Here, from the top 141 of the convex portion 140 to the boundary between the convex portion 140 and the recess 144, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 may increase continuously or stepwise. Also, for example, from the outer edge 145 of the lens 117 to the boundary between the convex portion 140 and the recess 144, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 may increase continuously or stepwise. The recess 144 exists at the boundary portion with the adjacent light-emitting element and surrounds the top 141.

[0016] In the configuration of the present embodiment shown in FIG. 1, the surface 151 of the lens 117 disposed for each of the light-emitting elements 101 includes a concave portion 143 surrounded by the convex portion 140 in the orthographic projection onto the main surface 152 of the substrate 108. Let the portion closest to the main surface 152 of the substrate 108 among the concave portions 143 be the portion 142. Also, for example, the portion 142 may be a portion of the concave portion 143 whose tangent line is parallel to the main surface 152 of the substrate 108. The boundary between the convex portion 140 and the concave portion 143 may be a set of inflection points where the surface 151 of the lens 117 changes from a convex shape to a concave shape. Also, for example, the boundary between the convex portion 140 and the concave portion 143 may be a set of positions (points) where the angle (inclination angle θ) of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 is maximized between the top portion 141 of the convex portion 140 and the portion 142 of the concave portion 143. Here, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 may increase continuously or stepwise from the top portion 141 of the convex portion 140 to the boundary between the convex portion 140 and the concave portion 143. Also, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 may increase continuously or stepwise from the portion 142 of the concave portion 143 to the boundary between the convex portion 140 and the concave portion 143.

[0017] Thus, the surface 151 of the lens 117 of the present embodiment has a ring shape including the convex portion 140 and the concave portion 143 surrounded by the convex portion 140. On the other hand, in the surface 151 of the lens 117' of the comparative example shown in FIG. 2, a concave portion 144' is disposed around the outer edge 145 of the lens 117 so as to surround the top portion 141, but there is no concave portion surrounded by the top portion 141. In the configuration of the present embodiment shown in FIG. 1, the concave portion 143 is disposed so as to overlap the center of the electrode 109. The portion 142 closest to the main surface 152 of the substrate 108 among the concave portions 143 may be disposed so as to overlap the center of the electrode 109. The center of the electrode 109 may be the geometric centroid position of the planar shape of the electrode 109 in the orthographic projection onto the main surface 152 of the substrate 108. Therefore, the concave portion 143 can also be regarded as being disposed at the center of the light-emitting element 101 in the orthographic projection onto the main surface 152 of the substrate 108.

[0018] The effects of the present embodiment will be described below. Here, the inclination angle at the boundary between the convex portion 140 and the concave portion 143, more specifically, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 between the top portion 141 of the convex portion 140 and the portion 142 of the concave portion 143 at the position where the angle is maximized is defined as the inclination angle θ1. Similarly, the inclination angle at the boundary between the convex portion 140 and the concave portion 144, more specifically, the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 between the top portion 141 of the convex portion 140 and the outer edge 145 of the lens 117 at the position where the angle is maximized is defined as the inclination angle θ2.

[0019] In this embodiment, the light-emitting element 101 includes a lens 117 having a concave portion 143 surrounded by a top portion 141 (convex portion 140). As a result, the top portion 141 becomes a point, and the inclination angles θ1 and θ2 can be made smaller compared to the lens 117' of the comparative example shown in FIG. 2 that does not include the concave portion 143. More specifically, in the configurations shown in FIGS. 1 and 2, for example, the shape of the convex portion 140 of the lens is a spherical surface (circle), and the radius of curvature in the cross-sectional view is made substantially the same. In that case, the inclination angles θ1 and θ2 at the respective boundaries between the convex portion 140 and the concave portion 143 and between the convex portion 140 and the concave portion 144 in this embodiment are smaller than the inclination angle θ2 at the boundary between the convex portion 140 and the concave portion 144 in the comparative example. That is, the relationships θ1 < θ2' and θ2 < θ2' are established. Considering the light refracted by the convex portion 140 and extracted in the front direction, the smaller the angle between the tangent of the convex portion 140 and the main surface 152 of the substrate 108, the more the light emitted from the light-emitting portion 132 in a direction closer to the front can be extracted in the front direction. As will be described later, when the optical distance between the electrodes 109 and 111 that function as reflection layers is optimized with respect to the front direction, the radiation intensity from the light-emitting portion 132 is the strongest in the front direction, and may become weaker as the emission angle increases. In that case, compared to the lens 117' of the comparative example shown in FIG. 2, the lens 117 of this embodiment shown in FIG. 1 can extract light with a smaller emission angle, that is, light with a relatively strong radiation intensity, in the front direction, and the radiation intensity in the front direction can be improved. In addition, the light emitted from the light-emitting portion 132 may have a worse color purity as the emission angle increases. Therefore, by the lens 117 having the configuration of this embodiment, light with a higher color purity can be extracted.

[0020] Furthermore, the concave portions 144 and 144' formed around the outer edge 145 of the convex portion 140 may be formed as a downwardly convex curved surface (concave surface, concave lens) for manufacturing reasons or the like. The downwardly convex curved surface has no light condensing property and acts in a direction to diffuse the light radiated from the light emitting portion 132, so it may not contribute to the extraction of light in the front direction. Therefore, when the ratio of the area occupied by the region (concave portion 144) which is a downwardly convex curved surface increases in the orthographic projection onto the main surface 152 of the substrate 108, the light extraction efficiency in the front direction may decrease. As described above, when the lens 117 of the present embodiment is compared with the lens 117' of the comparative example, θ2 < θ2' can be achieved. As a result, at the outer edge 145 of the lens 117, the curved surfaces intersect at a gentler angle with the adjacent lens 117. Therefore, in the lens 117 of the present embodiment, the width of the concave portion 144 can be reduced in a cross-sectional view. That is, the ratio occupied by the concave portion 144 can be reduced, and the front extraction efficiency can be improved. Also, in the configuration of the present embodiment shown in FIG. 1, a downwardly convex curved surface (concave surface, concave lens) may be formed in the concave portion 143 as well. However, the concave portion 143 exists as a dot-like region surrounded by the top portion 141. Therefore, the area occupied by the downwardly convex curved surface in the concave portion 143 can be made smaller than that of the concave portions 144 and 144' surrounding the top portion 141. Therefore, the influence on the decrease in the front extraction efficiency in the concave portion 143 is small. From another perspective, since the tilt angles θ1 and θ2 can be made small, the total area occupied by the downwardly convex curved surfaces in the concave portion 143 and the concave portion 144 of the lens 117 of the present embodiment can be made smaller than the area occupied by the downwardly convex curved surface in the concave portion 144 of the lens 117' of the comparative example. Therefore, the lens 117 of the present embodiment can improve the light front extraction efficiency.

[0021] As shown in FIG. 1, in the orthographic projection onto the main surface 152 of the substrate 108, the light-emitting portion 132 and at least a part of the convex portion 140 can be arranged so as to overlap. Further, for example, in the orthographic projection onto the main surface 152 of the substrate 108, the light-emitting portion 132 and the top portion 141 of the convex portion 140 may be arranged so as to overlap. Since the tangent line of the convex portion 140 at the top portion 141 is parallel to the main surface 152 of the substrate 108, by arranging the light-emitting portion 132 and the top portion 141 so as to overlap, the light radiated in the front direction from the light-emitting portion 132 toward the top portion 141 can be taken out in the front direction as it is. Therefore, the front extraction efficiency can be improved as compared with the case where the light-emitting portion 132 is arranged so as not to overlap the top portion 141.

[0022] Also, as shown in FIG. 1, in the orthographic projection onto the main surface 152 of the substrate 108, each of the plurality of light-emitting elements 101 may include a non-light-emitting portion 133 surrounded by the light-emitting portion 132. Thereby, in the orthographic projection onto the main surface 152 of the substrate 108, the light-emitting portion 132 and the concave portion 143 may be arranged so that the light-emitting portion 132 and the concave portion 143 do not overlap. In other words, in the orthographic projection onto the main surface 152 of the substrate 108, the non-light-emitting portion 133 and the concave portion 143 may be arranged so that the non-light-emitting portion 133 and the concave portion 143 overlap. Further, in the orthographic projection onto the main surface 152 of the substrate 108, the light-emitting portion 132 and the concave portion 144 may be arranged so that the light-emitting portion 132 and the concave portion 144 do not overlap. As described above, in the concave portions 143 and 144, a downwardly convex curved surface may be formed, and it may act in a direction to diffuse the light from the light-emitting portion 132. Therefore, even if the light-emitting portion 132 is arranged so as to overlap the concave portions 143 and 144, it may not contribute to the extraction of light in the front direction. Therefore, by arranging the light-emitting portion 132 so as not to overlap the concave portions 143 and 144, the front extraction efficiency of light can be improved.

[0023] In the configuration shown in FIG. 1, it has been described that the light emitting portion 132 does not overlap with the concave portion 143 and the concave portion 144. However, it is not limited thereto, and in the orthographic projection onto the main surface 152 of the substrate 108, the light emitting portion 132 may be arranged to overlap with the concave portion 143 and the concave portion 144. In such a configuration, the viewing angle characteristics can be improved.

[0024] In the configuration shown in FIG. 1, the shape of the outer edge of the light emitting portion 132 in the orthographic projection onto the main surface 152 of the substrate 108 can be a circle, and the shape of the outer edge of the non-light emitting portion 133 arranged to overlap with the concave portion 143 can also be a circle. That is, in the orthographic projection onto the main surface 152 of the substrate 108, it can be said that the shape of the light emitting portion 132 is ring-shaped. As described above, the concave portion 143 (portion 142) is arranged to overlap with the center of the electrode 109. Therefore, in the orthographic projection onto the main surface 152 of the substrate 108, the length between the center of the light emitting portion 132 and the top 141 of the convex portion 140 is longer than the length between the center of the light emitting portion 132 and the portion 142 closest to the main surface 152 of the substrate 108 among the concave portion 143. The center of the light emitting portion 132 is, for example, the geometric center of gravity position of the ring-shaped light emitting portion 132 in the orthographic projection onto the main surface 152 of the substrate 108. Here, the planar shape of the light emitting portion 132 in the present embodiment is not limited to a ring shape, and may be a circle, a polygon such as a square, a rectangle, or a hexagon, or a shape in which the inside thereof is cut out by a circle or a polygon. Further, it may be a shape in which a plurality of these figures are combined.

[0025] Next, when a medium layer having a refractive index different from that of the lens 117 is provided between the light emitting unit 132 and the lens 117, the refractive index range of the medium layer will be described with reference to FIGS. 3 and 4. The medium layer refers to the protective layer 113, the planarization layer 114, the color filter 115, and the planarization layer 116 disposed between the light emitting unit 132 and the lens 117 in the configuration shown in FIG. 1. FIGS. 3 and 4 are diagrams showing a configuration example in which medium layers 135a and 135b having different refractive indexes are provided between the light emitting unit 132 and the lens 117. Let the refractive index of the lens 117 be n1, the refractive index of the medium layer 135a be n2, and the refractive index of the medium layer 135b be n3. For example, the medium layer 135a may be the color filter 115. Also, for example, the medium layer 135b may be the protective layer 113.

[0026] In the configuration shown in FIG. 3, the magnitude relationship of the refractive indexes is n2 < n1 < n3. Considering the refraction of the light rays emitted obliquely from the light emitting unit 132, 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 135a and the lens 117. Therefore, as shown in FIG. 3, the light emitted from the light emitting unit 132 may be emitted from the lens 117 of the adjacent light emitting element 101 in a direction closer to the front. Therefore, crosstalk may occur between the light emitting elements 101, and the image quality may deteriorate. Also, since the emission angle from the light emitting unit 132 is large and light with poor color purity is likely to be visually recognized, the color purity may decrease.

[0027] On the other hand, in the configuration shown in FIG. 4, the magnitude relationship of the refractive indexes is n1 < n < n3. Therefore, the magnitude relationship of the angles a, b, and c is a < b < c, and the light emitted obliquely from the light emitting unit 132 is refracted toward the wider angle side at the interface between the medium layer 135a and the lens 117 and is less likely to be emitted in the front direction. Therefore, a decrease in color purity can be suppressed.

[0028] As described above, by adopting a configuration in which no layer with a refractive index smaller than the refractive index n1 of the lens 117 is disposed between the light-emitting portion 132 and the lens 117, crosstalk between the light-emitting elements 101 and a decrease in color purity can be suppressed. That is, the refractive indices of the medium layers 135a and 135b disposed between the light-emitting portion 132 and the lens 117 may be equal to or higher than the refractive index of the lens 117. For example, in the configuration shown in FIG. 4, the refractive index n1 of the lens 117 and the refractive index n2 of the medium layer 135a may satisfy the relationship n1 ≦ n2. Also, the refractive index n3 of the medium layer 135b disposed between the medium layer 135a and the light-emitting portion 132 may satisfy the relationship n1 ≦ n3. Further, the refractive index n3 of the medium layer 135b may satisfy the relationship n2 ≦ n3. The medium layer may have a laminated structure of three or more layers, and in that case as well, a configuration is adopted in which no layer with a refractive index smaller than the refractive index n1 of the lens 117 is disposed. Also, in adjacent medium layers, the refractive index of the medium layer farther from the light-emitting portion 132 may be equal to or higher than the refractive index of the medium layer closer to the light-emitting portion 132. Thereby, crosstalk between the light-emitting elements 101 and a decrease in color purity can be suppressed.

[0029] Next, with reference to FIG. 5, the positional relationship between the light-emitting portion 132 and the lens 117 will be described. FIG. 5 is a schematic diagram for explaining an example of a light ray taken out in the front direction in a part of the cross section of the light-emitting device 100 shown in FIG. 1. Hereinafter, consider a path in which light emitted from the light-emitting portion 132 is refracted at the interface between the lens 117 with a refractive index n1 and air with a refractive index 1 and taken out in the front direction. Here, as shown in FIG. 5, consider the path of the light 160 that is refracted at the position P2 where the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 is maximum between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117 and taken out in the front direction. In that case, let the length of the light 160 traveling in a direction parallel to the main surface 152 of the substrate 108 from the position P2 to the surface of the light-emitting portion 132 be the distance L. As shown in FIG. 5, when the light-emitting element 101 is an organic light-emitting element including the organic layer 120 containing the light-emitting layer, the surface of the light-emitting portion 132 may be considered as, for example, the surface of the electrode 111.

[0030] If the inclination angle of surface 151 of lens 117 at position P2 is θ2, then inside lens 117, angle β1 between light 160 and the normal to substrate 108 satisfies the relationship between the following equations (1) and (2) according to Snell's law. n1·sinα1=sinθ2· (1) β1=|θ2−α1| (2) Here, α1 can also be considered as the angle of incidence of the light 160 onto the convex portion 140.

[0031] If the thickness of lens 117 at position P2 (the distance perpendicular to main surface 152 of substrate 108) is H1, then the distance L1 that light 160 travels within lens 117 in a direction parallel to main surface 152 of substrate 108 is H1·tanβ1.

[0032] Next, for light 160 heading toward position P2 at angle β1, consider the distance traveled in a direction parallel to the main surface 152 of substrate 108 within each layer constituting the medium layer. The angle within each layer can be determined by taking into account refraction at each interface. Specifically, if there are N layers including the layer of lens 117, the layer of lens 117 is the first layer, and the refractive index of the ith layer from lens 117 to substrate 108 is defined as n i Then, the ray angle β in the i-th layer i is calculated using the following equation (3). n i sinβ i =n1 sinβ1 (3) From this, the distance L that the light ray travels in each layer in a direction parallel to the main surface 152 of the substrate 108 is i is the ray angle β in each layer. i Using this, it can be calculated using the following equation (4). L i =H i tanβ i (4) The distance L from the position P2 to the electrode 111 in the direction parallel to the main surface 152 of the substrate 108 is the horizontal distance L i can be calculated by adding up from i=1 to i=N, so the distance L is expressed by the following equation (5). L = H1·tanβ1 + H2·tanβ2 + ··· + H N ·tanβ N ··· (5)

[0033] As shown in FIG. 5, in the orthographic projection onto the main surface 152 of the substrate 108, the length from the position P2 to the outer edge of the light-emitting portion 132 closest to the position P2 is defined as the distance A. Further, among the light-emitting portions 132, the position P3 that emits light taken out in the direction perpendicular to the main surface 152 of the substrate 108 through the position P2 is, as described above, at a position at a distance L from the position P2 in the orthographic projection onto the main surface 152 of the substrate 108. In that case, the condition for the light 160 radiated from the light-emitting portion 132 to be refracted at the position P2 and taken out in the front direction may satisfy the relationship L > A. In other words, in the orthographic projection onto the main surface 152 of the substrate 108, the length (distance L) between the position P2 and the position P3 is longer than the length (distance A) between the position P2 and the outer edge of the light-emitting portion 132. By satisfying the relationship L > A, there is light 160 that is refracted at the position P2 and taken out in the front direction, and the front extraction efficiency can be improved as compared with the case where the relationship L > A is not satisfied.

[0034] Now, returning to FIG. 1, a more specific configuration example of the light-emitting device 100 will be described. As shown in FIG. 1, the light-emitting device 100 may include a substrate 108, an electrode 109, an organic layer 120, an electrode 111, an insulating layer 112, a protective layer 113, a planarization layer 114, a color filter 115, a planarization layer 116, and a lens 117. In the present embodiment, the electrodes 109 and 111 function as reflection layers that reflect light, as will be described later.

[0035] The electrode 109 is disposed on the main surface 152 of the substrate 108. The electrode 109 may also be referred to as a lower electrode. The organic layer 120 includes a light-emitting layer containing a light-emitting material. A part of the organic layer 120 (light-emitting layer) functions as the above-described light-emitting portion 132. The organic layer 120 is disposed between the substrate 108 and the lens 117 so as to cover the electrode 109. The electrode 111 is disposed on the organic layer 120. The electrode 111 may also be referred to as an upper electrode. The organic layer 120 (light-emitting layer) emits light due to the potential difference between the electrode 109 and the electrode 111.

[0036] The insulating layer 112 is disposed between adjacent electrodes 109 so that the adjacent electrodes 109 are insulated from each other. Further, the insulating layer 112 may be independently disposed on one electrode 109 so as to overlap with the concave portion 143. The insulating layer 112 may also be referred to as a bank. The insulating layer 112 is disposed, for example, at the outer edge of the electrode 109 on the electrode 109. The exposed portion of the electrode 109 that is not covered by the insulating layer 112 is in contact with the organic layer 120. The portion of the organic layer 120 that is in contact with the electrode 109 may become the above-described light-emitting portion 132. Therefore, as shown in FIG. 1, a plurality of light-emitting portions 132 corresponding to the plurality of electrodes 109 may be disposed in the light-emitting device 100.

[0037] The protective layer 113 is disposed on the electrode 111, and the planarization layer 114 is disposed on the protective layer 113. The color filter 115 may be disposed on the planarization layer 114 so as to correspond to each of the plurality of electrodes 109. The planarization layer 116 is disposed on the color filter 115. The lens 117 is disposed on the planarization layer 116. The lens 117 is disposed so as to correspond to each of the electrodes 109.

[0038] The material used for the substrate 108 is not particularly limited as long as it can support each component of the light-emitting device 100 such as the electrode 109, the organic layer 120, and the electrode 111. For example, glass, plastic, silicon, or the like may be used as the material of the substrate 108. Switching elements such as transistors, wiring patterns, interlayer insulating films, and the like may be provided on the main surface 152 of the substrate 108.

[0039] The electrode 109 can be arranged corresponding to each light-emitting element 101. The electrode 109 may be transparent or opaque to the light emitted from the light-emitting part 132. When the electrode 109 is opaque, the material of the electrode 109 may be a metal material with a reflectivity of 70% or more for the wavelength of the light emitted from the light-emitting part 132. For example, as the material of the electrode 109, metals such as aluminum (Al) and silver (Ag), or alloys obtained by adding silicon (Si), copper (Cu), nickel (Ni), neodymium (Nd), etc. to Al or Ag may be used. Further, the electrode 109 may be a transparent electrode such as ITO, IZO, AZO, IGZO, etc. In that case, an opaque reflective layer and the electrode 109 may be laminated with respect to the light emitted from the light-emitting part 132. If the required reflectivity can be obtained, the electrode 109 may be a laminated electrode with a barrier electrode such as a metal or its alloy like titanium (Ti), tungsten (W), molybdenum (Mo), gold (Au), etc., or may be a laminated electrode with a transparent oxide film electrode such as ITO or IZO. For the optimization of the optical distance described later, the electrode 109 may adopt a configuration in which an insulating film is provided between the reflective layer and the transparent conductive film.

[0040] The electrode 111 may be a semi-transmissive electrode having the property of transmitting a part of the light reaching the electrode 111 and reflecting the other part (i.e., semi-transmissive and reflective property). As the material of the electrode 111, for example, a transparent material such as a transparent conductive oxide may be used. Also, as the material of the electrode 111, a semi-transmissive material composed of a single metal (such as Al, Ag, Au), an alkali metal (such as lithium (Li), cesium (Cs)), an alkaline earth metal (such as magnesium (Mg), calcium (Ca), barium (Ba)), an alloy material containing these metal materials, etc. may be used. When a semi-transmissive material is used as the material of the electrode 111, an alloy mainly composed of Mg or Ag may be used as the semi-transmissive material. If the electrode 111 has an appropriate transmittance, the electrode 111 may have a laminated structure of a plurality of layers composed of the above-described materials. In the configuration shown in FIG. 1, a common electrode 111 is provided between the plurality of light-emitting portions 132. However, the present invention is not limited thereto, and a plurality of electrodes 111 corresponding to the plurality of light-emitting portions 132 may be arranged respectively.

[0041] One of the electrode 109 and the electrode 111 functions as an anode, and the other functions as a cathode. For example, the electrode 109 may function as an anode and the electrode 111 may function as a cathode. Also, for example, the electrode 109 may function as a cathode and the electrode 111 may function as an anode.

[0042] The organic layer 120 can be formed by known techniques such as vapor deposition method and spin coating method. The organic layer 120 may be composed of a plurality of layers. When the organic layer 120 is an organic compound layer, the organic layer 120 may be configured to include 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 the light-emitting layer.

[0043] The light-emitting layer emits light when holes injected from the anode and electrons injected from the cathode recombine within the light-emitting layer. The light-emitting layer may be a single layer or multiple layers. For example, when combining 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, the light (red light, green light, blue light) from each light-emitting layer mixes together to obtain white light. Two types of light-emitting layers whose emission 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 be combined. In the light-emitting device 100 shown in FIG. 1, each light-emitting unit 132 emits white light and is configured to be colored by the color filter 115. However, it is not limited to this. The material contained in the light-emitting layer and the configuration of the light-emitting layer may be made different for each light-emitting unit 132 so that each light-emitting unit 132 emits light of a different color. In that case, the light-emitting layer may be patterned for each light-emitting unit 132.

[0044] Also, in the organic layer 120, a so-called tandem structure having a plurality of light-emitting layers and charge generation layers provided between the plurality of light-emitting layers may be used. By adopting a tandem structure, the plurality of light-emitting layers emit light simultaneously, and the light-emitting efficiency can be improved.

[0045] Here, the electrode 109 will be described on the assumption that it reflects the light emitted by the light-emitting unit 132. In that case, in order to optimize the optical distance between the first reflection surface which is the surface of the electrode 109 and the light-emitting region (light-emitting position) of the organic layer 120 including the light-emitting layer, the following formula (6) may be satisfied. In formula (6), L r is the optical path length (optical distance) from the first reflection surface which is the surface of the electrode 109 to the light-emitting position of the organic layer 120, and Φ r is the phase shift when light of wavelength λ is reflected by the first reflection surface, and m is an integer of 0 or more. The film thickness between the electrode 109 and the organic layer 120, the film thickness of each layer of the organic layer 120, etc. may be designed so as to satisfy formula (6). L r =(2×m-(Φ r / π))×(λ / 4) ··· (6)

[0046] Also, the optical distance L from the light-emitting position to the second reflecting surface, which is the lower surface of the electrode 111 s is such that when light with a wavelength λ is reflected from the second reflecting surface, the phase shift is Φ s Let m2 be an integer of 0 or more. Then, it suffices to satisfy the following formula (7). L s =(2×m2 - (Φ s / π))×(λ / 4) ··· (7)

[0047] Therefore, the total layer interference L suffices to satisfy the following formula (8). In formula (8), Φ is the sum of the phase shift Φ r and the phase shift Φ s and m3 is an integer of 0 or more. L = L r + L s =(2×m3 - Φ / π)×(λ / 4) ··· (8)

[0048] Here, in the above formulas (6) to (8), the allowable range is about λ / 8 or about 20 nm. Since it may be difficult to specify the light-emitting position of the organic layer 120, in the above example, the light-emitting position is substituted with the interface on the first reflecting surface side or the second reflecting surface side of the light-emitting layer in the organic layer 120. Considering the above allowable range, even in such a substitution case, the effect of enhancing light can be obtained.

[0049] The protective layer 113, the planarization layer 114, the color filter 115, and the planarization layer 116 constitute the above-described medium layer 135. The protective layer 113 is a dielectric layer. Also, the protective layer 113 has light-transmitting properties that allow the light emitted by the light-emitting portion 132 to pass through. Further, the protective layer 113 may contain an inorganic material with low permeability to oxygen and moisture from the outside of the light-emitting device 100. For example, the protective layer 113 may be silicon nitride (SiN), silicon oxynitride (SiON), silicon oxide (SiO x) It may be formed using inorganic materials such as aluminum oxide (Al2O3) and titanium oxide (TiO2). In terms of protection performance, the protective layer 113 may be composed of inorganic materials such as SiN, SiON, and Al2O3. For the formation of the protective layer 113, chemical vapor deposition (CVD) method, atomic layer deposition (ALD) method, sputtering method, etc. may be used.

[0050] If the protective layer 113 has sufficient moisture barrier performance, it may have a single-layer structure using the above materials, or a laminated structure combining the above materials. For example, the protective layer 113 may have a laminated structure of a SiN layer formed by the CVD method and another layer with high density (e.g., Al2O3) formed by the ALD method. Furthermore, if the protective layer 113 has moisture barrier performance, it may contain an organic layer. For the organic layer, for example, polyacrylate, polyimide, polyester, epoxy, etc. may be used. Furthermore, in the configuration shown in FIG. 1, a common protective layer 113 is provided between the plurality of light-emitting portions 132, but a plurality of protective layers 113 corresponding to the plurality of light-emitting portions 132 may be arranged.

[0051] The lens 117 can be formed by an exposure process and a development process. Specifically, a material film of the lens 117 (e.g., a photoresist film) is formed, and the photoresist film is exposed and developed using a mask having a continuous gradation change. As the mask used for the formation of the lens 117, a gray mask can be used. By changing the density distribution of the dots of the light-shielding film below the resolution of the exposure apparatus, an area gradation mask that enables light irradiation having a continuous gradation change on the imaging surface can also be used as the mask for the formation of the lens 117. Also, by performing etch-back on the lens 117 formed by the exposure process and the development process, it is possible to adjust the lens shape. As described above, the surface 151 of the lens 117 has a convex portion 140 with a convex shape in a direction away from the main surface 152 of the substrate 108, and a part of the convex portion 140 may be a part of a spherical surface (circle) or aspherical.

[0052] The light-emitting element 101 is configured by combining the light-emitting part 132, the convex part 140 of the lens 117, the concave part 143, and the like. When a plurality of light-emitting elements 101 are provided, the planar arrangement of the plurality of light-emitting elements 101 (the arrangement when viewed from the normal direction of the main surface 152 of the substrate 108) may be any arrangement such as a stripe arrangement, a square arrangement, a delta arrangement, a pentile arrangement, a Bayer arrangement, or the like. FIGS. 6 to 8 are plan views of the light-emitting device 100 viewed from the side of the lens 117, and show an example of the planar arrangement of the plurality of light-emitting elements 101. FIG. 6 shows an example of a delta arrangement. FIG. 7 shows an example of a stripe arrangement. FIG. 8 shows an example of a Bayer arrangement. Here, consider a case where the light-emitting device 100 is used as a display panel, and one pixel (main pixel) includes a plurality of sub-pixels (for example, a sub-pixel for performing red display, a sub-pixel for performing green display, and a sub-pixel for performing blue display) whose corresponding color components are different from each other. In this case, as shown in FIG. 7, a plurality of light-emitting elements 101 may constitute one sub-pixel. The size, shape, and the like of the convex part 140 of the lens 117 may be appropriately set according to the method of the planar arrangement of the plurality of light-emitting elements 101. For example, when a delta arrangement is adopted, the area occupied by the convex part 140 on the surface 151 of the lens 117 with respect to the sub-pixel can be set large, and the light extraction efficiency can be increased.

[0053] In the configuration shown in FIGS. 6 to 8, the planar shape of the light-emitting part 132 (the shape when viewed from the normal direction of the main surface 152 of the substrate 108) is a ring shape, but the planar shape of the light-emitting part 132 is not limited to this. The planar shape of the light-emitting part 132 may be, for example, a polygon such as a quadrilateral or a hexagon, or a shape in which the inside thereof is further cut out in a circular or polygonal shape.

[0054] Further, the lens 117 may be formed such that the outer edge 145 of the convex part 140 constituting the surface 151 of the lens 117 has a thickness (a part of the lenses 117 adjacent to each other overlaps). In this case, as described above, the outer edge 145 of the lens 117 may be a set of portions where the tangent line of the surface 151 of the lens 117 is parallel to the main surface 152 of the substrate 108 (the inclination angle is 0°) between the lenses 117 adjacent to each other.

[0055] As described above, a configuration may be adopted in which light of different colors is transmitted by the lens 117. Thereby, full-color display becomes possible in the light-emitting device 100. As a method for realizing full-color display, a method using a light-emitting layer that emits white light and a color filter 115 may be adopted. Since the light-emitting layer can be shared among the plurality of light-emitting portions 132, the manufacturing process of the light-emitting layer becomes easier than the case where the light-emitting layer is patterned to emit different colors for each light-emitting portion 132. However, the light-emitting layer may be patterned so that the plurality of light-emitting portions 132 emit light of different colors from each other. Also, the optical path length L (optical path length L r , L s ) between the first reflective layer and the second reflective layer described above may be made different for each light-emitting portion 132 that emits light of a different color.

[0056] In the orthographic projection onto the main surface of the substrate, the center of the concave portion 143 of the convex portion 140 can be arranged at the center of the electrode 109 as described above. Also, the top portion 141 forms a circle, and the center of the circle can overlap with the centers of the electrode 109 and the light-emitting portion 132 in the orthographic projection onto the main surface 152 of the substrate 108. On the other hand, for the purpose of increasing the light extraction efficiency in a specific direction, the center of the light-emitting portion 132 and the center of the concave portion 143 may be arranged offset from each other. In the light-emitting element 101 arranged in the light-emitting device 100, they may be arranged offset in the same direction throughout, or in the vicinity of the center of the element region where the plurality of light-emitting elements 101 of the light-emitting device 100 are arranged, the center of the light-emitting portion 132 and the center of the concave portion 143 are arranged to overlap, and towards the outside of the element region, the offset between the center of the light-emitting portion 132 and the center of the concave portion 143 may be arranged to increase. In this case, the center of the concave portion 143 may be offset in the direction towards the outer peripheral portion of the light-emitting device 100 with respect to the center of the light-emitting portion 132.

[0057] In this embodiment, the color filter 115 is provided on the planarization layer 114. However, the present invention is not limited thereto, and the color filter 115 may be provided on the protective layer 113. For example, the planarization layer 114 may not be provided, and the color filter 115 and the protective layer 113 may be continuously arranged. Further, for example, the color filter 115 and the protective layer 113 may be integrated. The color filter 115 of the light-emitting device 100 may be formed by forming the color filter 115 on a support substrate different from the substrate 108 and bonding the color filter 115 to face the protective layer 113.

[0058] The planarization layer 114 is provided to planarize the unevenness on the surface of the protective layer 113. By arranging the planarization layer 114, the color filter 115 can be accurately aligned with respect to each light-emitting portion 132 and formed using a photolithography process. Further, as described above, by omitting the planarization layer 114 and integrating the color filter 115 and the protective layer 113, the color filter 115 can be accurately aligned with respect to the light-emitting portion 132 and formed using a photolithography process.

[0059] In the configuration shown in FIG. 1, the color filters 115r, 115g, and 115b may be color filters that transmit light of different colors. For example, the color filter 115r may transmit red light, the color filter 115g may transmit green light, and the color filter 115b may transmit blue light. Some or all of the plurality of color filters 115 may be omitted, and the light-emitting device 100 may be a device that emits a single emission color. Further, by separately forming the light-emitting layer in the organic layer 120 for each light-emitting element 101 and making the color of the light emitted by the light-emitting portion 132 different colors, the light-emitting device 100 may be a device capable of full-color display.

[0060] In addition, in the present embodiment, the lens 117 is provided on the planarization layer 116. The planarization layer 116 is provided to planarize the unevenness on the surface of the color filter 115. However, the lens 117 may be provided on the color filter 115. In that case, the planarization layer 116 may not be provided. Also, the lens 117 and the color filter 115 may be integrated.

[0061] Furthermore, the lens 117 may be provided on the protective layer 113 without the color filter 115, the planarization layers 114 and 116 being provided. For example, the lens 117 and the protective layer 113 may be integrated. When the lens 117 and the protective layer 113 are integrated, the distance from the lens 117 to the light emitting portion 132 can be made shorter than the case where the lens 117 is formed on another substrate and bonded to face the protective layer 113. As a result, the solid angle of the light incident from the light emitting portion 132 to the lens 117 can be widened, and the light extraction efficiency is improved. By integrating the lens 117 and the protective layer 113, the convex portion 140 of the lens 117 can be accurately aligned and formed with respect to the light emitting portion 132. Also, for example, by integrating the color filter 115, the lens 117, and the protective layer 113, the mutual alignment of the light emitting portion 132, the color filter 115, and the lens 117 can be performed with high precision.

[0062] The stacking order of the color filter 115 and the lens 117 can be appropriately selected. In the configuration shown in FIG. 1, the color filter 115 is provided on the side of the light emitting portion 132 with respect to the lens 117. In this configuration, the light emitted from the light emitting portion 132 passes through the color filter 115 before entering the lens 117. Thereby, light (light having a large emission angle from the light emitting portion) that causes a decrease in color purity passes through the color filter 115 over a relatively long distance. Therefore, a decrease in color purity when the light emitting device 100 is observed from an oblique direction can be further suppressed.

[0063] Further, the color filter 115 and the lens 117 may be formed on a support substrate different from the substrate 108, and bonded to face the substrate 108 having the light-emitting portion 132 to fabricate the light-emitting device 100. By forming the color filter 115 and the lens 117 separately from the organic layer 120 (light-emitting layer), the degree of freedom in the processing method (e.g., temperature, etc.) when forming the color filter 115 and the lens 117 is improved, and the degree of freedom in the design of the color filter 115 and the lens 117 can be increased. The color filter 115 and the lens 117 may be continuously formed on one support substrate, or the color filter 115 and the lens 117 may be formed on separate support substrates. The lens 117 and the color filter 115 can be bonded to the substrate 108 using a bonding member such as an adhesive. The bonding member may be disposed on the planarization layer 114, or may be disposed on the protective layer 113 when the planarization layer 114 is not provided.

[0064] The lens 117 may be formed on a support substrate different from the substrate 108 and bonded to face the substrate 108 having the light-emitting portion 132. In this case, the lens 117 may be fixed to the substrate 108 by a bonding member such as an adhesive at the end of the light-emitting device 100 so that a space is provided between the lens 117 and the protective layer 113 (or the color filter 115). In that case, the space may be filled with resin. The refractive index of the resin may be smaller than the refractive index n1 of the lens 117.

[0065] Hereinafter, examples of the light-emitting device 100 will be described in comparison with the light-emitting device 100' of the comparative example. In the examples described below, the light-emitting device 100 of Example 1 and the light-emitting device 100' of the comparative example have the same configuration except that the shapes of the light-emitting portion 132 and the lenses 117, 117' are different.

[0066] Example 1 First, aluminum was formed on the substrate 108, and a plurality of electrodes 109 corresponding to the respective light-emitting elements 101 were formed. Next, silicon oxide with a film thickness of 65 nm was formed as a material film of the insulating layer 112 so as to cover each of the plurality of electrodes 109. The insulating layer 112 was formed by forming openings in the central portions of the plurality of electrodes 109 in the formed material film to expose the electrodes 109. In the light-emitting device 100 of the present embodiment, the shape of the opening for exposing the electrode 109 is a circular shape with an outer diameter of 2.4 μm, and a circular insulating layer 112 with a radius of 1.0 μm remains inside. On the other hand, in the comparative example, the shape of the opening was a circular shape with a radius of 2.2 μm so that the area of the opening was substantially equal to that of the light-emitting device 100 of the present embodiment. As described above, finally, the opening provided in the insulating layer 112 corresponds to the light-emitting portion 132. That is, in the orthographic projection onto the main surface 152 of the substrate 108, the size and shape of the opening can coincide with the size and shape of the light-emitting portion 132.

[0067] After forming the insulating layer 112, an organic layer 120 was formed on the plurality of electrodes 109 and the insulating layer 112. Specifically, as a hole injection layer, Compound 1 shown below was formed to a thickness of 3 nm. On the hole injection layer, as a hole transport layer, Compound 2 was formed to a thickness of 15 nm. On the hole transport layer, as an electron blocking layer, Compound 3 was formed to a thickness of 10 nm. Next, the first light-emitting layer was formed to a thickness of 10 nm such that Compound 4 as a host material was 97% by weight and Compound 5 as a light-emitting dopant was 3% by weight. Next, the second light-emitting layer was formed to a thickness of 10 nm such that Compound 4 as a host material was 98% by weight and Compounds 6 and 7 as light-emitting dopants were each 1% by weight. Next, on the second light-emitting layer, as an electron transport layer, Compound 8 was formed to a thickness of 110 nm. Next, on the electron transport layer, as an electron injection layer, lithium fluoride was formed to a thickness of 1 nm.

[0068] [Chemical formula]

[0069] After the formation of the organic layer 120, an MgAg alloy was formed as the electrode 111 on the organic layer 120 with a thickness of 10 nm. The ratio of Mg to Ag was 1:1. Then, as the protective layer 113 on the electrode 111, SiN with a refractive index of 1.97 was formed with a thickness of 2.0 μm using the CVD method. Next, a planarization layer 114 with a refractive index of 1.55 was formed with a thickness of 0.2 μm on the protective layer 113 using the spin coating method.

[0070] Next, a color filter 115 with a refractive index of 1.65 was formed with a thickness of 1.6 μm on the planarization layer 114. The color filter 115r was a color filter that transmits red light, the color filter 115g was a color filter that transmits green light, and the color filter 115b was a color filter that transmits blue light. After the formation of the color filter 115, a planarization layer 116 with a refractive index of 1.55 was formed with a thickness of 0.2 μm on the color filter 115 using the spin coating method.

[0071] Next, a lens 117 with a refractive index of 1.52 was formed on the planarization layer 116 using an exposure process and a development process. The convex portion 140 of the lens 117 was made such that its cross-sectional shape was approximately a part of a spherical surface (circle). In the light-emitting device 100 of this embodiment, the distance h, which is the height difference between the top portion 141 of the convex portion 140 and the portion 142 of the concave portion 143 in the normal direction of the main surface 152 of the substrate 108, was set to 0.9 μm. Also, in the orthographic projection onto the main surface 152 of the substrate 108, the distance r1 between the top portion 141 of the convex portion 140 and the portion 142 of the concave portion 143, and the distance r2 between the top portion 141 of the convex portion 140 and the outer edge 145 of the lens 117 were both set to 1.65 μm. Therefore, the top portion 141 draws a circle with a radius of 1.65 μm in the orthographic projection onto the main surface 152 of the substrate 108. In this embodiment, the distance (pixel pitch P) between the centers of adjacent light-emitting elements 101 was 6.6 μm, and there was a relationship of r1 = 0.25P. At this time, the inclination angles θ1 and θ2 at the positions where the angles of the surface 151 of the lens 117 near the concave portion 143 and near the concave portion 144 with respect to the main surface 152 of the substrate 108 were maximum were both about 55°.

[0072] In the light-emitting device 100' of the comparative example, the height difference (the height of the lens 117') between the top 141 and the outer edge 145 of the convex portion 140 in the normal direction of the main surface of the substrate 108 was set to 2.5 μm. Also, in the orthographic projection onto the main surface 152 of the substrate 108, the distance (the bottom radius of the lens 117') between the top 141 of the convex portion 140 of the lens 117' and the outer edge 145 of the lens 117' was set to 3.3 μm. At this time, the inclination angle θ2' at the position where the angle of the surface 151 of the lens 117' with respect to the main surface 152 of the substrate 108 was maximized was about 70°.

[0073] When comparing the light-emitting device 100 of this example with the light-emitting device 100' of the comparative example, while the sizes of the light-emitting portions 132 are substantially equal, the maximum inclination angles θ1 and θ2 of the main surface 152 of the substrate 108 near the concave portions 143 and 144 in the light-emitting device 100 of this example are smaller than the inclination angle θ2' of the light-emitting device 100' of the comparative example. As described above, in the light-emitting device 100 of this example, since the maximum inclination angle of the surface 151 of the lens 117 can be reduced, light with a small emission angle from the light-emitting portion 132 can be extracted forward. Further, in the orthographic projection onto the main surface 152 of the substrate 108, the light-emitting device 100 of this example can make the area occupied by the concave portions 143 and 144 in the light-emitting element 101 smaller than the area occupied by the concave portion 144' in the light-emitting element 101 of the light-emitting device 100' of the comparative example. As a result, the light-emitting device 100 of this example can increase the amount of light extracted forward and can extract light with high color purity.

[0074] Example 2 Next, the light-emitting device 100 of Example 2 will be described with reference to FIG. 9. FIG. 9 is a schematic cross-sectional view of the light-emitting device 100 of this example.

[0075] In this example, two independent light-emitting portions 132 are arranged as the light-emitting portion 132 in one light-emitting element 101. Specifically, one light-emitting portion 132 has a ring shape with an outer diameter of 2.6 μm and an inner diameter of 1.6 μm. The other light-emitting portion 132 has a circular shape with a radius of 0.8 μm. In that case, the shape is such that the centers of gravity of the two light-emitting portions 132 coincide.

[0076] Furthermore, in this embodiment, the shape of the lens 117 is different from that of the lens 117 in the first embodiment. As shown in FIG. 9, the lens 117 of this embodiment further includes a convex portion 146 that is surrounded by the concave portion 143 and protrudes in a direction away from the main surface 152 of the substrate 108, in addition to the convex portion 140 that surrounds the concave portion 143. The convex portion 146 includes a vertex 147 whose tangent line is parallel to the main surface 152 of the substrate 108.

[0077] Here, in the orthographic projection onto the main surface 152 of the substrate 108, the top 141 of the convex portion 140 is circular as in the first embodiment and surrounds the concave portion 143. In the orthographic projection onto the main surface 152 of the substrate 108, the concave portion 143 is also circular. On the other hand, in the orthographic projection onto the main surface 152 of the substrate 108, the vertex 147 of the convex portion 146 is a "point".

[0078] In this embodiment, the distance h, which is the height difference between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143 in the normal direction of the main surface 152 of the substrate 108, was set to 0.4 μm. Also, in the orthographic projection onto the main surface 152 of the substrate 108, the distance r3 between the vertex 147 of the convex portion 146 and the portion 142 of the concave portion 143, the distance r4 between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143, and the distance r5 between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117 were each set to 1.1 μm. At this time, the inclination angles θ1 and θ2 at the positions where the angles of the surface 151 of the lens 117 near the concave portion 143 and near the concave portion 144 with respect to the main surface 152 of the substrate 108 are maximized were both about 38°. Other configurations are the same as those of the light-emitting device 100 in the first embodiment.

[0079] As in this embodiment, even when the concave portion 143 is circular in the orthographic projection onto the main surface 152 of the substrate 108, the maximum inclination angles θ1 and θ2 of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 can be made smaller than those of the light-emitting device 100' of the comparative example. As a result, the amount of light extracted in the front direction can be increased, and light with high color purity can be extracted.

[0080] In this embodiment, the case where the recess 143 is a single circle in the orthographic projection onto the main surface 152 of the substrate 108 has been described, but the present invention is not limited thereto. Even if the recess 143 has a configuration of a plurality of concentric circles or a configuration of drawing a single or a plurality of polygons, the maximum inclination angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 can be reduced. That is, the effects of the present disclosure described above can be obtained.

[0081] Example 3 Next, the light-emitting device 100 of Example 3 will be described with reference to FIG. 10. FIG. 10 is a schematic cross-sectional view of the light-emitting device 100 of this embodiment.

[0082] In this embodiment, the shape of the light-emitting portion 132 is a circular shape with an outer diameter of 2.75 μm, and an insulating layer 112 having a circular shape with a radius of 1.65 μm remains inside.

[0083] Furthermore, in this embodiment, the shape of the lens 117 is different from that of the lens 117 in Embodiments 1 and 2. In the orthographic projection of the lens 117 in this embodiment onto the main surface 152 of the substrate 108, the distance r1 between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143 is 2.2 μm, and the distance r2 between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117 is 1.1 μm. Also, the distance h, which is the height difference between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143 in the normal direction of the main surface 152 of the substrate 108, is 1.5 μm. At this time, the inclination angle θ1 at the position where the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 is maximum in the vicinity of the concave portion 143 was about 65°. Also, the inclination angle θ2 at the position where the angle of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 is maximum in the vicinity of the concave portion 144 was about 27°. That is, the maximum angle (inclination angle θ2) of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117 is smaller than the maximum angle (inclination angle θ1) of the surface 151 of the lens 117 with respect to the main surface 152 of the substrate 108 between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143 closest to the main surface 152 of the substrate 108. Also, in the normal direction of the main surface 152 of the substrate 108, the length between the outer edge 145 of the lens 117 and the main surface 152 of the substrate 108 is longer than the length between the portion 142 of the concave portion 143 and the main surface 152 of the substrate 108. Other configurations are the same as those of the light-emitting device 100 in Embodiment 1.

[0084] In the orthographic projection onto the main surface 152 of the substrate 108, when the width of the region that is a downwardly convex curved surface is the same, the area of the region near the concave portion 144, which is the peripheral portion of one light-emitting element 101, is larger than the area of the region near the concave portion 143 at the center of the light-emitting element 101. Therefore, the influence on the light extraction efficiency can be greater in the region near the concave portion 144. Thus, as in this embodiment, the maximum inclination angle θ2 of the surface 151 of the lens 117 between the top 141 and the outer edge 145 with respect to the main surface 152 of the substrate 108 is made smaller than the maximum inclination angle θ1 of the surface 151 of the lens 117 between the top 141 and the portion 142. Thereby, the amount of light extracted in the front direction is improved.

[0085] In this embodiment, by setting the relationship of r1 > r2, the relationship of θ1 > θ2 was realized. However, it is not limited to this. For example, by making the curvature of the surface 151 of the lens 117 different between the top 141 of the convex portion 140 and the portion 142 of the concave portion 143, and between the top 141 of the convex portion 140 and the outer edge 145 of the lens 117, the relationship of θ1 > θ2 may be realized.

[0086] Here, application examples in which the light-emitting device 100 of the present embodiment is applied to an image forming device, a display device, a photoelectric conversion device, an electronic device, a lighting device, a moving body, and a wearable device will be described with reference to FIGS. 11(a) to 11(c) and FIGS. 18(a) and 18(b).

[0087] FIGS. 11(a) to 11(c) are schematic views showing an example of an image forming device using the light-emitting device 100 of the present embodiment. The image forming device 926 shown in FIG. 11(a) includes a photoreceptor 927, an exposure light source 928, a developing unit 931, a charging unit 930, a transferrer 932, a conveying unit 933 (in the configuration of FIG. 11(a), a conveying roller), and a fixing unit 935.

[0088] Light 929 is irradiated from the exposure light source 928, and an electrostatic latent image is formed on the surface of the photoreceptor 927. The light-emitting device 100 can be applied to this exposure light source 928. The developing unit 931 includes toner or the like as a developer and can function as a developing device that applies the developer to the exposed photoreceptor 927. The charging unit 930 charges the photoreceptor 927. The transferrer 932 transfers the developed image to the recording medium 934. The conveying unit 933 conveys the recording medium 934. The recording medium 934 can be, for example, paper or film. The fixing unit 935 fixes the image formed on the recording medium.

[0089] FIG. 11(b) and FIG. 11(c) are schematic diagrams showing a state in which a plurality of light emitting portions 936 are arranged along the longitudinal direction on a long substrate in an exposure light source 928. The light emitting device 100 can be applied to the light emitting portion 936. That is, a plurality of pixels are arranged along the longitudinal direction of the substrate. The direction 937 is a direction parallel to the axis of the photoreceptor 927. This column direction is the same as the direction of the axis when the photoreceptor 927 rotates. This direction 937 can also be called the major axis direction of the photoreceptor 927.

[0090] FIG. 11(b) shows a form in which the light emitting portion 936 is arranged along the major axis direction of the photoreceptor 927. FIG. 11(c) is a modification of the arrangement of the light emitting portion 936 shown in FIG. 11(b), and is a form in which the light emitting portions 936 are alternately arranged in the column direction in each of the first column and the second column. In the first column and the second column, the light emitting portions 936 are arranged at different positions in the row direction. In the first column, a plurality of light emitting portions 936 are arranged at intervals, and in the second column, the light emitting portions 936 are arranged at positions corresponding to the gaps between the light emitting portions 936 in the first column. Also, in the row direction, a plurality of light emitting portions 936 are arranged at intervals. The arrangement of the light emitting portions 936 shown in FIG. 11(c) can also be described as, for example, a state of being arranged in a grid pattern, a state of being arranged in a staggered grid, or a checkerboard pattern.

[0091] FIG. 12 is a schematic diagram showing an example of a display device using the light emitting device 100 of the present 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 FPC1002 and 1004. Active elements such as transistors are arranged on the circuit board 1007. The battery 1008 may not be provided if the display device 1000 is not a portable device, or even if it is a portable device, it is not necessary to be provided at this position. The light emitting device 100 can be applied to the display panel 1005. The pixels arranged in the light emitting device 100 functioning as the display panel 1005 are connected to and operate with active elements such as transistors arranged on the circuit board 1007.

[0092] The display device 1000 shown in FIG. 12 may be used in the display unit of a photoelectric conversion device (which may also be called an imaging device) having an optical unit with a plurality of lenses and an imaging element that receives the light that has passed through the optical unit and performs photoelectric conversion into an electrical signal. The photoelectric conversion device may have a display unit that displays the information acquired by the imaging element. Further, the display unit may be a display unit exposed to the outside of the photoelectric conversion device or a display unit disposed within the viewfinder. The photoelectric conversion device may be a digital camera or a digital video camera.

[0093] FIG. 13 is a schematic diagram showing an example of a photoelectric conversion device using the light-emitting device 100 of the present embodiment. The photoelectric conversion device 1100 may have 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 100 of the present embodiment can be applied to the viewfinder 1101 and the rear display 1102 which are display units. In this case, the light-emitting device 100 may display not only the 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 moves, the possibility that the subject is blocked by an obstacle, and the like.

[0094] Since the timing suitable for imaging is often a very short time, it is better to display the information as soon as possible. Therefore, the light-emitting device 100 including pixels in which light-emitting elements using organic light-emitting materials such as organic EL elements are arranged may be used for the viewfinder 1101 and the rear display 1102. This is because the response speed of the organic light-emitting material is fast. The light-emitting device 100 using an organic light-emitting material is more suitable for these devices, which require a high display speed, than a liquid crystal display device.

[0095] The photoelectric conversion device 1100 has an optical unit (not shown). The optical unit has a plurality of lenses and forms an image on a photoelectric conversion element (not shown) housed within the housing 1104 that receives the light that has passed through the optical unit. The plurality of lenses can adjust the focus by adjusting their relative positions. This operation can also be performed automatically.

[0096] The light-emitting device 100 may be applied to the display unit of an electronic device. In that case, it may have both a display function and an operation function. Examples of the portable terminal include mobile phones such as smartphones, tablets, and head-mounted displays.

[0097] FIG. 14 is a schematic diagram showing an example of an electronic device using the light-emitting device 100 of the present embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The housing 1203 may have 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 reaction unit of a touch panel method. The operation unit 1202 may be a biometric recognition unit that recognizes a fingerprint and performs unlocking or the like. A portable device having a communication unit can also be called a communication device. The light-emitting device 100 of the present embodiment can be applied to the display unit 1201.

[0098] FIGS. 15(a) and 15(b) are schematic diagrams showing an example of a display device using the light-emitting device 100 of the present embodiment. FIG. 15(a) is a display device such as a TV monitor or a PC monitor. The display device 1300 has a frame 1301 and a display unit 1302. The light-emitting device 100 of the present 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 of FIG. 15(a). For example, the lower side of the frame 1301 may also serve as the base 1303. Further, 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.

[0099] FIG. 15(b) is a schematic diagram showing another example of a display device using the light-emitting device 100 of the present embodiment. The display device 1310 in FIG. 15(b) is configured to be foldable and is a so-called foldable display device. The display device 1310 includes a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. The light-emitting device 100 of the present 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 seamless display device. The first display unit 1311 and the second display unit 1312 can be separated at the bending point. The first display unit 1311 and the second display unit 1312 may display different images, or may display one image together.

[0100] FIG. 16 is a schematic diagram showing an example of an illumination device using the light-emitting device 100 of the present embodiment. The illumination device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusing portion 1405. The light-emitting device 100 of the present embodiment can be applied to the light source 1402. The optical film 1404 may be a filter that improves the color rendering property of the light source. The light diffusing portion 1405 can effectively diffuse the light of the light source, such as lighting up, and deliver the light to a wide range. Optionally, a cover may be provided on the outermost side. The illumination device 1400 may have both the optical film 1404 and the light diffusing portion 1405, or may have only one of them.

[0101] The lighting device 1400 is, for example, a device for lighting an interior. The lighting device 1400 may emit any color from white, warm white, to other colors from blue to red. It may have a dimming circuit for dimming them. The lighting device 1400 may have a power supply circuit connected to the light-emitting device 100 that functions as a light source 1402. The power supply circuit is a circuit that converts an AC voltage into a DC voltage. Also, white has a color temperature of 4200K and warm white has a color temperature of 5000K. Further, the lighting device 1400 may have a color filter. Also, the lighting device 1400 may have a heat dissipation part. The heat dissipation part releases the heat inside the device to the outside of the device, and examples include metals with high specific heat and liquid silicone.

[0102] FIG. 17 is a schematic diagram of an automobile having a tail lamp, which is an example of a vehicle lamp using the light-emitting device 100 of the present embodiment. The automobile 1500 has a tail lamp 1501, and when a brake operation or the like is performed, the tail lamp 1501 may be lit. The light-emitting device 100 of the present embodiment may be used as a head lamp as a vehicle lamp. An automobile is an example of a moving body, and the moving body may be a ship, a drone, an aircraft, a railway vehicle, an industrial robot, or the like. The moving body may have a body and a lamp provided thereon. The lamp may notify the current position of the body.

[0103] The light-emitting device 100 of the present embodiment can be applied to the tail lamp 1501. The tail lamp 1501 may have a protection member that protects the light-emitting device 100 that functions as the tail lamp 1501. The protection member has a certain degree of strength, and the material may be any as long as it is transparent, and it may be made of polycarbonate or the like. Also, the protection member may be mixed with a phthalic acid derivative, an acrylonitrile derivative, or the like in polycarbonate.

[0104] Automobile 1500 may have a vehicle 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 100 of the present embodiment may be used for the transparent display. In this case, constituent materials such as electrodes included in the light-emitting device 100 are formed of transparent members.

[0105] Referring to FIGS. 18(a) and 18(b), a further application example of the light-emitting device 100 of the present embodiment will be described. The light-emitting device 100 can be applied to, for example, a system wearable as a wearable device such as smart glasses, a head-mounted display (HMD), or smart contact. The imaging display device used in such an application example includes an imaging device capable of photoelectrically converting visible light and a light-emitting device capable of emitting visible light.

[0106] FIG. 18(a) illustrates glasses 1600 (smart glasses) according to one application example. An imaging device 1602 such as a CMOS sensor or a SPAD is provided on the front surface side of the lens 1601 of the glasses 1600. Further, the light-emitting device 100 of the present embodiment is provided on the back surface side of the lens 1601.

[0107] The glasses 1600 further include a control device 1603. The control device 1603 functions as a power supply that supplies power to the imaging device 1602 and the light-emitting device 100 according to each embodiment. Further, the control device 1603 controls the operations of the imaging device 1602 and the light-emitting device 100. An optical system for condensing light onto the imaging device 1602 is formed in the lens 1601.

[0108] FIG. 18(b) illustrates glasses 1610 (smart glasses) according to one application example. The glasses 1610 have a control device 1612, and the control device 1612 is equipped with an imaging device corresponding to the imaging device 1602 and a light emitting device 100. In the lens 1611, an optical system for projecting the light emitted from the imaging device in the control device 1612 and the light emitting device 100 is formed, 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 100, and controls the operations of the imaging device and the light emitting device 100. The control device 1612 may have a line-of-sight detection unit for detecting the wearer's line of sight. Infrared rays may be used for line-of-sight detection. The infrared light emitting unit emits infrared light to the eyeball of the user who is gazing at the display image. An imaging image of the eyeball is obtained by detecting the reflected light of the emitted infrared light from the eyeball by an imaging unit having a light receiving element. By having a reducing means for reducing the light from the infrared light emitting unit to the display unit in a plan view, a decrease in image quality is reduced.

[0109] The user's line of sight with respect to the display image is detected from the imaging image of the eyeball obtained by imaging infrared light. Any known method can be applied to the line-of-sight detection using the imaging image of the eyeball. As an example, a line-of-sight detection method based on the Purkinje image by the reflection of the irradiation light on the cornea can be used.

[0110] More specifically, a line-of-sight detection process based on the pupil corneal reflection method is performed. Using the pupil corneal reflection method, a line-of-sight vector representing the orientation (rotation angle) of the eyeball is calculated based on the image of the pupil and the Purkinje image included in the imaging image of the eyeball, whereby the user's line of sight is detected.

[0111] The light emitting device 100 according to the embodiment of the present disclosure may have an imaging device having a light receiving element, and may control a display image based on the user's line-of-sight information from the imaging device.

[0112] Specifically, the light-emitting device 100 determines a first visual field region that the user gazes at and a second visual field region other than the first visual field region based on the line-of-sight information. The first visual field region and the second visual field region may be determined by the control device of the light-emitting device 100, or may be received as determined by an external control device. In the display region of the light-emitting device 100, the display resolution of the first visual field region may be controlled to be higher than that of the second visual field region. That is, the resolution of the second visual field region may be made lower than that of the first visual field region.

[0113] Further, the display region has a first display region and a second display region different from the first display region, and based on the line-of-sight information, a region with a higher priority is determined from the first display region and the second display region. The first display region and the second display region may be determined by the control device of the light-emitting device 100, or may be received as determined by an external control device. The resolution of the region with a higher priority may be controlled to be higher than that of the region other than the region with a higher priority. That is, the resolution of the region with a relatively lower priority may be made lower.

[0114] Note that AI may be used to determine the first visual field region or the region with a higher priority. AI may be a model configured to estimate the angle of the line of sight and the distance to the target at the tip of the line of sight from the eye image using the eye image and the direction in which the eye in the image is actually looking as teacher data. The AI program may be possessed by the light-emitting device 100, the imaging device, or an external device. When it is possessed by an external device, it is transmitted to the light-emitting device 100 via communication.

[0115] When performing display control based on visual recognition detection, it can be applied to smart glasses that further include an imaging device for imaging the outside. The smart glasses can display the imaged external information in real time.

[0116] The disclosure of this specification includes the following light-emitting devices, image forming devices, display devices, photoelectric conversion devices, and electronic devices.

[0117] (Item 1) A light-emitting device in which a plurality of light-emitting elements are arranged on the main surface of a substrate, Each of the plurality of light-emitting elements includes a light-emitting portion and a lens. The surface of the lens is characterized in that a convex bulge continuously extends along the direction along the main surface, and includes a convex portion having a positive power and a concave portion surrounded by the convex portion. The light-emitting device is characterized by this.

[0118] (Item 2) The light-emitting device according to Item 1, wherein in a orthographic projection onto the main surface, the light-emitting portion and at least a part of the convex portion overlap each other.

[0119] (Item 3) The light-emitting device according to Item 1 or 2, wherein in a orthographic projection onto the main surface, the light-emitting portion and a portion of the convex portion whose tangent line is parallel to the main surface overlap each other.

[0120] (Item 4) The light-emitting device according to any one of Items 1 to 3, wherein the length between the outer edge of the lens and the main surface is longer than the length between the portion of the concave portion closest to the main surface and the main surface.

[0121] (Item 5) The light-emitting device according to Item 4, wherein the maximum angle of the surface with respect to the main surface between the portion of the convex portion whose tangent line is parallel to the main surface and the outer edge of the lens is smaller than the maximum angle of the surface with respect to the main surface between the parallel portion and the portion of the concave portion closest to the main surface.

[0122] (Item 6) The light-emitting device according to any one of Items 1 to 5, wherein in a orthographic projection onto the main surface, each of the plurality of light-emitting elements further includes a non-light-emitting portion surrounded by the light-emitting portion.

[0123] (Item 7) The light-emitting device according to item 6, wherein in the orthographic projection onto the main surface, the light-emitting portion and the portion of the concave portion closest to the main surface do not overlap.

[0124] (Item 8) The light-emitting device according to item 6 or 7, wherein in the orthographic projection onto the main surface, the non-light-emitting portion and the portion of the concave portion closest to the main surface overlap.

[0125] (Item 9) The light-emitting device according to any one of items 1 to 8, wherein in the orthographic projection onto the main surface, the light-emitting portion and the outer edge of the lens do not overlap.

[0126] (Item 10) A medium layer is disposed between the light-emitting portion and the lens, The light-emitting device according to any one of items 1 to 9, wherein the refractive index of the medium layer is equal to or greater than the refractive index of the lens.

[0127] (Item 11) Taking the medium layer as the first medium layer, A second medium layer is disposed between the light-emitting portion and the first medium layer, The light-emitting device according to item 10, wherein the refractive index of the first medium layer is equal to or less than the refractive index of the second medium layer.

[0128] (Item 12) When the position where the angle of the surface with respect to the main surface is maximum between the portion of the convex portion whose tangent is parallel to the main surface and the outer edge of the lens is defined as the first position, and the position of the light-emitting portion that emits light transmitted through the first position and taken out in a direction perpendicular to the main surface is defined as the second position, The light-emitting device according to any one of items 1 to 11, wherein in the orthographic projection onto the main surface, the length between the first position and the second position is longer than the length between the first position and the outer edge of the light-emitting portion.

[0129] (Item 13) In the orthographic projection onto the main surface, the length between the center of the light-emitting portion and the portion of the convex portion where the tangent line thereof is parallel to the main surface is longer than the length between the center and the portion of the concave portion closest to the main surface. The light-emitting device according to any one of Items 1 to 12, characterized in that.

[0130] (Item 14) Taking the convex portion as the first convex portion, The surface further includes a second convex portion surrounded by the concave portion and protruding in a direction away from the main surface. The light-emitting device according to any one of Items 1 to 13, characterized in that the light-emitting portion and at least a part of the second convex portion are arranged to overlap.

[0131] (Item 15) When the position where the angle of the surface with respect to the main surface is maximum between the portion of the convex portion where the tangent line thereof is parallel to the main surface and the outer edge of the lens is defined as the first position, and the position where the angle of the surface with respect to the main surface is maximum between the parallel portion and the concave portion is defined as the third position, From the parallel portion to the first position, the angle of the surface with respect to the main surface increases continuously or stepwise. From the parallel portion to the third position, the angle of the surface with respect to the main surface increases continuously or stepwise. The light-emitting device according to any one of Items 1 to 14, characterized in that from the portion of the concave portion closest to the main surface to the third position, the angle of the surface with respect to the main surface increases continuously or stepwise.

[0132] (Item 16) A light-emitting device in which a plurality of light-emitting elements are arranged on the main surface of a substrate. Each of the plurality of light-emitting elements includes a light-emitting portion and a lens. The surface of the lens includes a convex bulge continuously extending in a direction along the main surface, a convex portion having positive power, and a first concave portion and a second concave portion adjacent to each other through the convex portion. The maximum angle of the surface with respect to the main surface between a portion of the convex portion whose tangent line is parallel to the main surface and a portion of the second concave portion closest to the main surface is smaller than the maximum angle of the surface with respect to the main surface between the parallel portion and a portion of the first concave portion closest to the main surface. A light-emitting device, wherein, in a orthographic projection onto the main surface, the first concave portion is arranged at a position closer to the center of the light-emitting portion than the second concave portion.

[0133] (Item 17) An image forming apparatus having a photoreceptor, an exposure light source for exposing the photoreceptor, a developing device for applying a developer to the exposed photoreceptor, and a transfer device for transferring an image developed by the developing device onto a recording medium. An image forming apparatus, wherein the exposure light source has the light-emitting device according to any one of Items 1 to 16.

[0134] (Item 18) A display device having the light-emitting device according to any one of Items 1 to 16 and an active element connected to the light-emitting device.

[0135] (Item 19) An optoelectronic conversion device having 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. The display unit displays an image captured by the image sensor and has the light-emitting device according to any one of Items 1 to 16.

[0136] (Item 20) An electronic device having a housing provided with a display unit and a communication unit provided in the housing for communicating with the outside. The display unit has the light-emitting device according to any one of Items 1 to 16.

[0137] The invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the invention. Accordingly, the claims are appended to disclose the scope of the invention.

Explanation of Symbols

[0138] 100: Light-emitting device, 101: Light-emitting element, 108: Substrate, 117: Lens, 132: Light-emitting section, 140: Protrusion, 143: Recess, 151: Surface, 152: Main surface

Claims

1. A light-emitting device in which a plurality of light-emitting elements are arranged on a main surface of a substrate, each of the plurality of light-emitting elements includes a light-emitting portion and a lens, wherein a surface of the lens includes a convex portion having a convex bulge continuously extending in a direction along the main surface and having a positive power, and a concave portion surrounded by the convex portion, and the light-emitting device is characterized by this.

2. The light-emitting device according to claim 1, wherein in a orthographic projection onto the main surface, the light-emitting portion and at least a part of the convex portion are arranged so as to overlap.

3. The light-emitting device according to claim 1, wherein in a orthographic projection onto the main surface, the light-emitting portion and a portion of the convex portion whose tangent line is parallel to the main surface are arranged so as to overlap.

4. The light-emitting device according to claim 1, wherein a length between an outer edge of the lens and the main surface is longer than a length between a portion of the concave portion closest to the main surface and the main surface.

5. The light-emitting device according to claim 4, wherein a maximum angle of the surface with respect to the main surface between a portion of the convex portion whose tangent line is parallel to the main surface and the outer edge of the lens is smaller than a maximum angle of the surface with respect to the main surface between the parallel portion and a portion of the concave portion closest to the main surface.

6. The light-emitting device according to claim 1, wherein in a orthographic projection onto the main surface, each of the plurality of light-emitting elements further includes a non-light-emitting portion surrounded by the light-emitting portion.

7. The light-emitting device according to claim 6, wherein in a orthographic projection onto the main surface, the light-emitting portion and a portion of the concave portion closest to the main surface do not overlap.

8. The light-emitting device according to claim 6, wherein in a orthographic projection onto the main surface, the non-light-emitting portion and a portion of the concave portion closest to the main surface overlap.

9. The light-emitting device according to claim 1, wherein in a orthographic projection onto the main surface, the light-emitting portion and the outer edge of the lens do not overlap.

10. A medium layer is arranged between the light-emitting portion and the lens, and the light-emitting device according to claim 1 is characterized in that a refractive index of the medium layer is equal to or higher than a refractive index of the lens.

11. Taking the medium layer as a first medium layer, a second medium layer is arranged between the light-emitting portion and the first medium layer, The light-emitting device according to claim 10, wherein the refractive index of the first medium layer is less than or equal to the refractive index of the second medium layer.

12. When a position where the angle of the surface with respect to the main surface between a portion of the convex portion whose tangent is parallel to the main surface and the outer edge of the lens is maximum is defined as a first position, and a position of the light-emitting portion that emits light transmitted through the first position and taken out in a direction perpendicular to the main surface is defined as a second position, In the orthographic projection onto the main surface, the length between the first position and the second position is longer than the length between the first position and the outer edge of the light-emitting portion, according to the light-emitting device of claim 1.

13. In the orthographic projection onto the main surface, the length between the center of the light-emitting portion and a portion of the convex portion whose tangent is parallel to the main surface is longer than the length between the center and the portion of the concave portion closest to the main surface, according to the light-emitting device of claim 1.

14. Regarding the convex portion as a first convex portion, The surface further includes a second convex portion surrounded by the concave portion and protruding in a direction away from the main surface, The light-emitting device according to claim 1, wherein the light-emitting portion and at least a part of the second convex portion are arranged to overlap.

15. When a position where the angle of the surface with respect to the main surface between a portion of the convex portion whose tangent is parallel to the main surface and the outer edge of the lens is maximum is defined as a first position, and a position where the angle of the surface with respect to the main surface between the parallel portion and the concave portion is maximum is defined as a third position, From the parallel portion to the first position, the angle of the surface with respect to the main surface increases continuously or stepwise, From the parallel portion to the third position, the angle of the surface with respect to the main surface increases continuously or stepwise, From the portion of the concave portion closest to the main surface to the third position, the angle of the surface with respect to the main surface increases continuously or stepwise, according to the light-emitting device of claim 1.

16. A light-emitting device in which a plurality of light-emitting elements are arranged on a main surface of a substrate, Each of the plurality of light-emitting elements includes a light-emitting portion and a lens, The surface of the lens includes a convex bulge continuously extending in a direction along the main surface, a convex portion having positive power, and a first concave portion and a second concave portion adjacent to each other through the convex portion. The maximum angle of the surface with respect to the main surface between a portion of the convex portion whose tangent line is parallel to the main surface and the portion of the second concave portion closest to the main surface is smaller than the maximum angle of the surface with respect to the main surface between the parallel portion and the portion of the first concave portion closest to the main surface. An illuminating device, wherein in a orthographic projection with respect to the main surface, the first concave portion is arranged at a position closer to the center of the light-emitting portion than the second concave portion.

17. A photoreceptor, an exposure light source for exposing the photoreceptor, a developing device for applying a developer to the exposed photoreceptor, and a transfer device for transferring an image developed by the developing device onto a recording medium. An image forming apparatus, wherein the exposure light source has the illuminating device according to any one of claims 1 to 16.

18. A display device, comprising the illuminating device according to any one of claims 1 to 16 and an active element connected to the illuminating device.

19. 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 unit displays an image captured by the image sensor and has the illuminating device according to any one of claims 1 to 16.

20. A housing provided with a display unit, and a communication unit provided in the housing for communicating with the outside. An electronic device, wherein the display unit has the illuminating device according to any one of claims 1 to 16.

Images