Light emitting device and planar light source

Abstract

To provide a light emitting device capable of efficiently spreading light from a light emitting element in a lateral direction.SOLUTION: The light-emitting device includes a support having a wall portion, a light-emitting element mounted on the support and surrounded by the wall portion in a plan view, a first light-transmissive member having a first outer surface and a second outer surface located above the first outer surface and inward of the first outer surface in a plan view and covering the light-emitting element and the wall portion, and a light-shielding member covering the first light-transmissive member. In a cross-sectional view, the upper surface of the wall portion has an inclined surface inclined downward toward the outside, and the first outer surface and the second outer surface are exposed from the light-shielding member.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a light emitting device and a surface light source. [Background technology]

[0002] Patent Document 1 discloses a light emitting device in which a reflective resin is provided on the upper surface of a transparent resin that seals a light emitting element, and light from the light emitting element is emitted to the outside from the side surface of the transparent resin. Such a light emitting device easily spreads light laterally, and can be used, for example, as a light source for a backlight. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-115280 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for a light emitting device that can more efficiently spread light from a light emitting element in the lateral direction. According to an embodiment of the present invention, a light emitting device that can efficiently spread light from a light emitting element in the lateral direction is provided. [Means for solving the problem]

[0005] In one embodiment, the light emitting device has a support having a wall portion, a light emitting element placed on the support and surrounded by the wall portion in a planar view, a first outer surface, and a second outer surface located above the first outer surface and located inside the first outer surface in a planar view, and is equipped with a first translucent member covering the light emitting element and the wall portion, and a light-shielding member covering the first translucent member, wherein the first outer surface and the second outer surface are exposed from the light-shielding member, and the surface roughness of the first outer surface is coarser than the surface roughness of the second outer surface. [Effects of the Invention]

[0006] According to the light emitting device of one embodiment of the present invention, light from the light emitting element can be efficiently spread in the lateral direction. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic plan view illustrating a light-emitting device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along line II-II shown in FIG. [Figure 3] 2 is a schematic plan view of the light emitting device shown in FIG. 1, from which a first light-transmissive member, a second light-transmissive member, and a light-blocking member are omitted. [Figure 4A] FIG. 2 is a schematic plan view showing a first lead and a second lead according to the embodiment. [Figure 4B] FIG. 2 is a schematic bottom view showing a first lead and a second lead according to the embodiment. [Figure 5] FIG. 10 is a schematic plan view of a modified example of the light emitting device according to the present embodiment, in which the first light-transmissive member, the second light-transmissive member, and the light-blocking member are omitted. [Figure 6] 5A to 5C are schematic cross-sectional views illustrating a method for manufacturing the light emitting device according to the embodiment. [Figure 7A] FIG. 10 is a schematic cross-sectional view of another modified example of the light emitting device according to the embodiment. [Figure 7B] FIG. 10 is a schematic cross-sectional view of yet another modified example of the light emitting device according to the embodiment. [Figure 7C] FIG. 10 is a schematic cross-sectional view of yet another modified example of the light emitting device according to the embodiment. [Figure 8] 7D is a schematic cross-sectional view showing an exemplary method for manufacturing the light emitting device shown in FIG. 7C. [Figure 9] FIG. 10 is a schematic plan view showing yet another modified example of the light emitting device according to the embodiment. [Figure 10] FIG. 10 is a schematic cross-sectional view taken along line XX shown in FIG. [Figure 11] 10 is a schematic plan view of the light emitting device shown in FIG. 9, from which the first light-transmissive member, the second light-transmissive member, and the light-blocking member are omitted. [Figure 12A]10 is a schematic plan view showing a first lead and a second lead of the light emitting device shown in FIG. [Figure 12B] 10 is a schematic bottom view showing a first lead and a second lead of the light emitting device shown in FIG. 9. FIG. [Figure 13A] FIG. 10 is a schematic cross-sectional view of yet another modified example of the light emitting device according to the embodiment. [Figure 13B] FIG. 10 is a schematic cross-sectional view of yet another modified example of the light emitting device according to the embodiment. [Figure 14] FIG. 10 is a schematic cross-sectional view showing yet another modified example of the light emitting device according to the embodiment. [Figure 15] 15 is a schematic plan view of the light emitting device shown in FIG. 14, from which the first light-transmissive member, the second light-transmissive member, and the light-blocking member are omitted. FIG. [Figure 16] 15 is a schematic plan view showing a first lead and a second lead of the light emitting device shown in FIG. 14. FIG. [Figure 17] FIG. 10 is a schematic plan view showing yet another modified example of the light emitting device according to the embodiment. [Figure 18] FIG. 18 is a schematic cross-sectional view taken along line XVIII-XVIII shown in FIG. [Figure 19] 18 is a schematic plan view of the light emitting device shown in FIG. 17, from which the first light-transmissive member, the second light-transmissive member, and the light-blocking member are omitted. [Figure 20] 18 is a schematic plan view showing a first lead and a second lead of the light emitting device shown in FIG. 17. FIG. [Figure 21] FIG. 1 is a schematic plan view of a surface light source according to an embodiment of the present invention. [Figure 22] FIG. 22 is a schematic cross-sectional view taken along line XXII-XXII shown in FIG. 21. [Figure 23] FIG. 10 is a schematic cross-sectional view showing a modified example of the surface light source according to the embodiment. [Figure 24] FIG. 10 is a schematic cross-sectional view showing another modified example of the surface light source according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each drawing is a schematic representation of an embodiment of the present invention. Therefore, the scale, spacing, and positional relationship of each component may be exaggerated, and some components may not be shown. Also, in the following, end views may be shown as cross-sectional views. Note that the same reference symbols are used for the same components in each drawing.

[0009] In the following description, components having substantially the same functions are denoted by common reference symbols, and their descriptions may be omitted. In addition, terms indicating specific directions or positions (e.g., "upper," "lower," and other terms including these terms) may be used below. However, these terms are used merely to facilitate understanding of relative directions or positions in the referenced drawings. As long as the relative direction or position relationship indicated by terms such as "upper" and "lower" in the referenced drawings is the same, the arrangement in drawings other than those disclosed herein, actual products, etc., may not be the same as in the referenced drawings. Unless otherwise specified, "parallel" in this specification includes not only cases where two lines, sides, surfaces, etc. do not intersect even when extended, but also cases where the angle between the two lines, sides, surfaces, etc. is within a range of 5°. In this specification, the positional relationship expressed as "upper" includes both cases where the two lines, sides, surfaces, etc. are in contact with each other and cases where the two lines, sides, surfaces, etc. are not in contact with each other but are located above each other.

[0010] <Embodiment> The light emitting device 100 according to this embodiment will be described with reference to Fig. 1 to Fig. 8. For reference, arrows indicating the mutually orthogonal X, Y, and Z directions are depicted in Fig. 1 to Fig. 8. In the schematic cross-sectional view shown in Fig. 2, the horizontal direction is the X and / or Y direction, and the vertical direction is the Z direction.

[0011] The light emitting device 100 includes a support 10, a light emitting element 20, a first light-transmissive member 30, and a light-blocking member 40. The light emitting device 100 may further include a second light-transmissive member 50 and a wire 60. The support 10 has a wall portion 12. The light emitting element 20 is placed on the support 10. In a plan view, the light emitting element 20 is surrounded by the wall portion 12. The first light-transmissive member 30 covers the light emitting element 20 and the wall portion 12. The first light-transmissive member 30 has a first outer surface 31 and a second outer surface 32. The second outer surface 32 is located above the first outer surface 31. In a plan view, the second outer surface 32 is located inside the first outer surface 31. The light-blocking member 40 covers the first light-transmissive member 30. The first outer surface 31 is exposed from the light-blocking member 40. The second outer surface 32 is exposed from the light-shielding member 40. The surface roughness of the first outer surface 31 is greater than the surface roughness of the second outer surface 32.

[0012] The first outer surface 31 is located below the second outer surface 32 and is located outside the second outer surface 32 in a plan view. Therefore, the first outer surface 31 is more likely to be hit by light emitted from the light-emitting element 20 and having a large horizontal (X and / or Y) component than the second outer surface 32. In this specification, light having a large horizontal (X and / or Y) component means that when light emitted from the light-emitting element is divided into a component traveling in the vertical (Z) direction and a component traveling in the horizontal (X and / or Y) direction, the proportion of the component traveling in the horizontal (X and / or Y) direction is higher than the component traveling in the vertical (Z) direction. In addition, the second outer surface 32 is more likely to be hit by light emitted from the light-emitting element and having a large vertical (Z) component than the first outer surface 31. In addition, the light emitted from the light-emitting element also includes light reflected by the outer surface of the first light-transmissive member 30, etc.

[0013] Because the surface of the first outer surface 31 is rougher than the surface of the second outer surface 32, the surface area of ​​the first outer surface 31 can be made larger than if the surface of the first outer surface 31 were not rough. This makes it easier to extract light from the light emitting element 20 to the outside of the light emitting device 100 from the first outer surface 31. The first outer surface 31, which is likely to be hit by light emitted from the light emitting element 20 and has a large lateral component, makes it easier to extract light from the light emitting element 20 to the outside of the light emitting device, so the light emitting device 100 can efficiently spread the light from the light emitting element 20 in the lateral direction.

[0014] In the light emitting device 100, the light-blocking member 40 covers the upper surface of the light emitting element 20 via the first light-transmissive member 30. Therefore, part of the light traveling upward from the light emitting element 20 is blocked by the light-blocking member 40. As a result, the light emitted from the light emitting device 100 tends to have a large lateral component (X direction and / or Y direction).

[0015] Each element constituting the light emitting device 100 will be described in detail below.

[0016] (Support 10) The support 10 is a member on which the light-emitting element 20 is placed. As shown in FIG. 3, the support 10 has a base 11 and a wall 12. The base 11 has a mounting surface 11A on which the light-emitting element 20 is placed. The mounting surface 11A is located on the upper surface of the base 11. In a plan view, the wall 12 surrounds the mounting surface 11A. Also, in a plan view, the wall 12 surrounds the light-emitting element 20. The wall 12 is located above the base 11. The wall 12 shown in FIG. 3 has a first wall 12A, a second wall 12B, a third wall 12C, and a fourth wall 12D. The first wall 12A extends in the X direction. The second wall 12B extends in the X direction opposite the first wall 12A. The third wall portion 12C is located between the first wall portion 12A and the second wall portion 12B and extends in the Y direction. The fourth wall portion 12D is located between the first wall portion 12A and the second wall portion 12B and extends in the Y direction opposite the third wall portion 12C.

[0017] As shown in FIGS. 2 and 3, the support 10 may include a resin member 13, a first lead 14A, and a second lead 14B. The resin member 13 is a member located between the first lead 14A and the second lead 14B and holding the first lead 14A and the second lead 14B. The wall portion 12 may be formed from the resin member 13. When the wall portion 12 is formed from the resin member 13, it can be said that the wall portion 12 is a portion of the resin member 13 located above the upper surfaces of the first lead 14A and the second lead 14B. The base 11 may be formed from a part of the resin member 13, the first lead 14A, and the second lead 14B. The support 10 may include three or more leads.

[0018] Known materials such as thermosetting resins and thermoplastic resins can be used as the material for the resin member 13. Examples of thermoplastic resins that can be used include polyphthalamide resin, polybutylene terephthalate (PBT), and unsaturated polyester. Examples of thermosetting resins that can be used include epoxy resin, modified epoxy resin, silicone resin, and modified silicone resin. It is preferable to use a thermosetting resin such as epoxy resin or silicone resin, which has excellent heat resistance and light resistance, as the material for the resin member 13.

[0019] The material of the resin member 13 preferably contains a light-reflecting substance. As the light-reflecting substance, it is preferable to use a material that does not easily absorb light from the light-emitting element 20 and has a large difference in refractive index from the resin material. Examples of such light-reflecting substances include titanium oxide, zinc oxide, silicon oxide, zirconium oxide, aluminum oxide, and aluminum nitride. The light-reflecting substance can be contained in an amount of, for example, 10% by weight to 90% by weight of the resin material.

[0020] The first lead 14A and the second lead 14B are each electrically connected to either the negative or positive electrode of the pair of electrodes of the light-emitting element 20 to energize the light-emitting element 20. The first lead 14A and the second lead 14B can be formed into a predetermined shape using metals such as copper, aluminum, gold, silver, iron, nickel, or alloys thereof, phosphor bronze, or iron-bearing copper, by rolling, punching, extrusion, wet or dry etching, or a combination of these processes. They may be single-layer or have a multilayer structure. Copper, which is inexpensive and has high heat dissipation properties, is particularly preferred for the first lead 14A and the second lead 14B. To improve reflectivity, the first lead 14A and the second lead 14B may be partially or entirely plated with a metal such as silver, aluminum, copper, or gold in a single layer or multilayer structure. When a silver-containing metal layer is formed on the outermost surface of the first lead 14A and the second lead 14B, a protective layer such as silicon oxide is preferably provided on the surface of the silver-containing metal layer. This makes it possible to prevent the silver-containing metal layer from being discolored by sulfur components in the atmosphere, etc. Examples of methods for forming the protective layer include known methods such as vacuum processes such as sputtering.

[0021] 2, it is preferable that the first lead 14A and the second lead 14B are exposed from the resin member 13 on the lower surface of the light emitting device 100. In this way, heat from the light emitting device 100 is more easily transferred to the mounting board on which the light emitting device 100 is mounted via the first lead 14A and the second lead 14B. This makes it possible to improve the heat dissipation properties of the light emitting device 100.

[0022] As shown in FIG. 4A, a first groove 15 (shown by hatching) is preferably provided on the upper surface of the first lead 14A and / or the second lead 14B. The first groove 15 is recessed downward from the upper surface of the first lead 14A and / or the second lead 14B. The first groove 15 can be formed by etching, pressing, or the like. The first groove 15 is disposed around the mounting surface 11A in a plan view. A part of the resin member 13 is disposed within the first groove 15. This improves adhesion between the resin member 13 and the first lead 14A and / or the second lead 14B.

[0023] As shown in FIG. 4B, a second groove 16 (shown by hatching) is preferably provided on the lower surface of the first lead 14A and / or the second lead 14B. The second groove 16 is recessed upward from the lower surface of the first lead 14A and / or the second lead 14B. The second groove 16 can be formed by etching, pressing, or the like. The second groove 16 is disposed along the outer edge of the first lead 14A and / or the second lead 14B. Another part of the resin member 13 is disposed within the second groove 16. This improves adhesion between the resin member 13 and the first lead 14A and / or the second lead 14B.

[0024] (Light emitting element 20) The light emitting element 20 is a semiconductor element that emits light by itself when a voltage is applied, and known semiconductor elements made of nitride semiconductors or the like can be used for the light emitting element 20. An example of the light emitting element 20 is an LED chip. The light emitting element 20 includes a semiconductor laminate. The semiconductor laminate includes an n-type semiconductor layer, a p-type semiconductor layer, and a light emitting layer sandwiched between them. The light emitting layer may have a structure such as a double heterojunction or a single quantum well (SQW), or may have a structure with a group of active layers such as a multiple quantum well (MQW). The semiconductor laminate is configured to be able to emit visible light or ultraviolet light. A semiconductor laminate including such a light emitting layer can be formed using, for example, In x Al y Ga 1-x-y N (0≦x, 0≦y, x+y≦1).

[0025] The semiconductor laminate may have a structure including one or more light-emitting layers between an n-type semiconductor layer and a p-type semiconductor layer, or may have a structure in which a structure including an n-type semiconductor layer, a light-emitting layer, and a p-type semiconductor layer in that order is repeated multiple times. When the semiconductor laminate includes multiple light-emitting layers, the multiple light-emitting layers may include light-emitting layers with different emission peak wavelengths or light-emitting layers with the same emission peak wavelength. Incidentally, "same emission peak wavelength" also includes cases where the emission peak wavelengths vary within ±10 nm. The combination of emission peak wavelengths between the multiple light-emitting layers can be appropriately selected. For example, when the semiconductor laminate includes two light-emitting layers, the light-emitting layers can be selected from combinations such as blue light and blue light, green light and green light, red light and red light, ultraviolet light and ultraviolet light, blue light and green light, blue light and red light, or green light and red light. Each light-emitting layer may include multiple active layers with different emission peak wavelengths or multiple active layers with the same emission peak wavelength.

[0026] A single light-emitting element 20 may be mounted in one light-emitting device, or multiple light-emitting elements may be mounted. When a single light-emitting device includes multiple light-emitting elements 20, multiple light-emitting elements with the same peak emission wavelength may be combined to improve the luminous intensity of the entire light-emitting device. Furthermore, color reproducibility may be improved by combining multiple light-emitting elements with different peak emission wavelengths, for example, to correspond to red, green, and blue. When a light-emitting device includes multiple light-emitting elements, all of the light-emitting elements may be connected in series, in parallel, or in a combination of series and parallel connections. The light-emitting elements 20 may be mounted face-up, with the surface on which the electrodes are formed facing up, or may be mounted flip-chip, with the surface on which the electrodes are formed facing down. The light-emitting elements 20 of the light-emitting device 100 are mounted face-up, and electrical connection is achieved via wires 60.

[0027] One side of the rectangular shape of the light-emitting element 20 in plan view may be parallel to the X direction or the Y direction, or the light-emitting element 20 may be mounted on the mounting surface 11A with one side of the rectangular shape tilted with respect to the X direction and the Y direction as shown in Fig. 3. By mounting the light-emitting element 20 on the mounting surface 11A with one side of the rectangular shape of the light-emitting element 20 tilted with respect to the X direction and the Y direction in plan view, the light distribution characteristics of the light-emitting device 100 can be changed compared to when one side of the rectangular shape is parallel to the X direction or the Y direction. For example, one side of the rectangular shape of the light-emitting element 20 in plan view may be tilted at an angle of 35° to 60° with respect to the X direction.

[0028] As shown in FIG. 3, the light emitting device 100 may include two or more rectangular light emitting elements 20. The two light emitting elements 20 may be referred to as a first light emitting element 20A and a second light emitting element 20B. The short side of the first light emitting element 20A and the short side of the second light emitting element 20B may face each other, or as shown in FIG. 3, the long side of the first light emitting element 20A and the long side of the second light emitting element 20B may face each other. It is preferable that one side of the first light emitting element 20A and one side of the second light emitting element 20B facing each other are parallel. This makes it easier to miniaturize the light emitting device 100 in the X direction and / or Y direction.

[0029] As shown in FIG. 5, the light emitting elements 20 may overlap the resin member 13 in a planar view, or as shown in FIG. 3, the light emitting elements 20 may not overlap the resin member 13 in a planar view. As shown in FIG. 3, it is preferable that all of the light emitting elements 20 overlap the first lead 14A in a planar view. The first lead 14A generally conducts heat more easily than the resin member 13. Therefore, by having all of the light emitting elements 20 overlap the first lead 14A in a planar view, heat from the light emitting elements 20 is more easily conducted to the first lead 14A, thereby improving the heat dissipation of the light emitting device 100. It is also preferable that all of the light emitting elements 20 overlap the second lead 14B in a planar view instead of the first lead 14A, as this improves the heat dissipation of the light emitting device 100. Furthermore, when the light emitting device 100 has one light emitting element 20, the entire light emitting element 20 may overlap the first lead 14A or the second lead 14B in a planar view, or the light emitting element 20 may partially overlap the first lead 14A and / or the second lead 14B in a planar view.

[0030] (First translucent member 30) The first light-transmissive member 30 is a member that is translucent to light from the light-emitting element 20. The first light-transmissive member 30 covers the light-emitting element 20 and the wall portion 12 of the support 10. This allows light from the light-emitting element 20 to be extracted to the outside of the light-emitting device 100 through the first light-transmissive member 30. As shown in FIG. 2, the first light-transmissive member 30 covers the upper surface 20S of the light-emitting element 20 and the upper surface 12S of the wall portion 12. The first light-transmissive member 30 may cover the upper surface 20S of the light-emitting element 20 via the second light-transmissive member 50, or may cover the light-emitting element 20 by contacting the upper surface 20S of the light-emitting element 20. In this specification, having light transmissivity means that the transmittance at the peak wavelength of the light-emitting element is 50% or more. When the light-emitting device includes multiple light-emitting elements, it is sufficient that the transmittance at the peak wavelength of at least one light-emitting element is 50% or more.

[0031] The first light-transmissive member 30 has a first outer surface 31 and a second outer surface 32. The second outer surface 32 is located above the first outer surface 31 and is located more inward than the first outer surface in a planar view. In other words, the first outer surface 31 is located below the second outer surface 32 and is located more outward than the second outer surface in a planar view. Because the first outer surface 31 is located below the second outer surface 32 and more outward than the first outer surface in a planar view, the first outer surface 31 is more likely to be hit by light emitted from the light-emitting element 20 and having a large lateral component than the second outer surface 32. Furthermore, the surface roughness of the first outer surface 31 is greater than that of the second outer surface 32. Therefore, the first outer surface 31 is more likely to extract light from the light-emitting element 20 to the outside of the light-emitting device 100 than the second outer surface 32. This makes it easier to extract light from the light-emitting element 20 to the outside from the first outer surface 31, which is more likely to be hit by light with a large lateral component, and therefore the light-emitting device 100 can efficiently spread the light from the light-emitting element 20 in the lateral direction. In a plan view, the first outer surface 31 and the second outer surface 32 preferably surround the light-emitting element 20. This makes it possible to more efficiently spread the light from the light-emitting element 20 in the lateral direction. Furthermore, the second outer surface 32 is smoother than the first outer surface 31, and therefore it is more difficult for light from the light-emitting element 20 to be extracted from the second outer surface 32 than from the first outer surface 31. Therefore, by changing the shape of the second outer surface 32, it becomes easier to control the light distribution characteristics of the light-emitting device 100.

[0032] In this specification, the surface roughness of the first outer surface 31 and the surface roughness of the second outer surface 32 refer to the arithmetic mean roughness Ra defined in JIS standard B0601:2013. The arithmetic mean roughness Ra can be measured using a laser microscope or a contact surface roughness measuring instrument. The value of the arithmetic mean roughness Ra described in this specification is a value obtained by measurement using, for example, a laser microscope VK-X3000 (lens magnification 50x) manufactured by Keyence Corporation.

[0033] Although the specific value of the arithmetic mean roughness of the first outer surface 31 is not particularly limited, it is preferably 1.2 to 5.0 times the arithmetic mean roughness of the second outer surface 32. When the arithmetic mean roughness of the first outer surface 31 is 1.2 times or more the arithmetic mean roughness of the second outer surface 32, light from the light-emitting element 20 can be easily extracted to the outside from the first outer surface 31. When the arithmetic mean roughness of the first outer surface 31 is 5.0 times or less the arithmetic mean roughness of the second outer surface 32, chipping of a portion of the first outer surface 31 can be easily prevented. The arithmetic mean roughness of the first outer surface 31 is preferably 100 nm to 500 nm. When the arithmetic mean roughness of the first outer surface 31 is 100 nm or more, light from the light-emitting element 20 can be easily extracted to the outside from the first outer surface 31. When the arithmetic mean roughness of the first outer surface 31 is 500 nm or less, chipping of a portion of the first outer surface 31 can be easily prevented. The arithmetic mean roughness of the second outer surface 32 is preferably 50 nm or more and 200 nm or less. When the arithmetic mean roughness of the second outer surface 32 is 50 nm or more, light from the light emitting element 20 can be easily extracted to the outside from the second outer surface 32. When the arithmetic mean roughness of the second outer surface 32 is 200 nm or less, chipping of part of the second outer surface 32 can be easily prevented. Furthermore, when the arithmetic mean roughness of the second outer surface 32 is 200 nm or less, the light distribution characteristics of the light emitting device 100 can be easily controlled by the shape of the second outer surface 32.

[0034] As shown in FIG. 2, in a cross-sectional view, the first angle θ1 formed between the first outer surface 31 and the lower surface 10B of the support 10 is preferably smaller than the second angle θ2 formed between the second outer surface 32 and the lower surface 10B of the support 10. As a result, the upwardly traveling component of the light emitted from the light-emitting element 20 is less likely to hit the first outer surface 31, so the lateral component of the light extracted from the first outer surface 31 to the outside of the light-emitting device 100 tends to be larger. Note that in this specification, the first angle θ1 is the angle formed between a plane including the first outer surface 31 and a plane including the lower surface 10B of the support 10. As shown in FIG. 2, the first angle θ1 is an angle defined at the point where the plane including the first outer surface 31 intersects with the plane including the lower surface 10B of the support 10, and refers to an angle located above the lower surface 10B of the support 10 and located farther from the center of the light-emitting device. Similarly, in this specification, the second angle θ2 is the angle formed between a plane including the second outer surface 32 and a plane including the lower surface 10B of the support 10. As shown in FIG. 2, the second angle θ2 is an angle defined at the point where the plane including the second outer surface 32 and the plane including the lower surface 10B of the support 10 intersect, and refers to an angle located above the lower surface 10B of the support 10 that is farther from the center of the light-emitting device. Note that the second outer surface 32 inclines in a direction away from the center of the light-emitting device as it approaches the lower surface 10B of the support 10. Furthermore, the lower surface 10B of the support 10 shown in FIG. 2 extends in the horizontal direction (X direction).

[0035] Although the first light-transmissive member 30 shown in Fig. 2 has four-fold rotational symmetry with respect to the Z direction, this is not limiting. For example, the first light-transmissive member 30 may or may not be symmetric with respect to the YZ plane passing through the center of the light-emitting device. Furthermore, in the cross-sectional view shown in Fig. 2, the magnitude of the second angle formed between the second outer surface 32 located on the left side of the center (YZ plane) of the light-emitting device and the lower surface 10B of the support body 10 may be different from the magnitude of the second angle formed between the second outer surface 32 located on the right side of the center (YZ plane) of the light-emitting device and the lower surface 10B of the support body 10.

[0036] The specific value of the first angle θ1 is not particularly limited, but is preferably 85° or more and 95° or less. When the first angle θ1 is 85° or more and 95° or less, the upward component of the light emitted from the light-emitting element 20 is less likely to hit the first outer surface 31. As a result, the light emitted from the light-emitting device 100 is more likely to have a large lateral component. The specific value of the second angle θ2 is not particularly limited, but is preferably 100° or more and 150° or less. When the second angle θ2 is 100° or more, the light from the light-emitting element 20 is more likely to hit the second outer surface 32. As a result, the light extraction efficiency of the light-emitting device 100 is improved. When the second angle θ2 is 150° or less, the light emitted from the light-emitting element 20 with a large lateral component is more likely to hit the second outer surface 32. As a result, the light emitted from the light-emitting device 100 is more likely to have a large lateral component.

[0037] As shown in FIG. 2, it is preferable that the first outer surface 31 and the outer surface of the wall portion 12 are flush. This makes it easier to miniaturize the light-emitting device in the lateral direction. The first outer surface 31 and the outer surface of the wall portion 12 (see FIG. 2) may be formed by cutting the structure shown in FIG. 6 along dashed lines C1 and C2 in FIG. 6. This makes it easy to make the first outer surface 31 and the outer surface of the wall portion 12 flush. Known methods can be used for cutting. For example, cutting may be done using a blade or laser light.

[0038] The assembly of light emitting devices may be separated into individual light emitting devices by cutting along dashed lines C1 and C2 as shown in Fig. 6. In this specification, the assembly of light emitting devices refers to a structure in which the light emitting devices before separation are connected by the support 10 and the first light-transmissive member 30.

[0039] The first outer surface 31 may be formed by cutting, and the second outer surface 32 may be formed using a mold. In this way, the surface roughness of the first outer surface 31 can be easily made rougher than the surface roughness of the second outer surface 32. Alternatively, the first outer surface 31 and the second outer surface 32 may be formed by the same method, and then the surface roughness of the first outer surface 31 may be made rough. For example, after the first outer surface 31 and the second outer surface 32 are formed using a mold, the surface of the first outer surface 31 may be roughened by blasting.

[0040] The base material of the first light-transmissive member 30 can be, for example, a resin material. A thermosetting resin is preferable as the resin used for the base material of the first light-transmissive member 30. Examples of thermosetting resins include epoxy resin, modified epoxy resin, silicone resin, modified silicone resin, acrylate resin, urethane resin, and fluorine-based resin. Among them, silicone resin and modified silicone resin are preferable because of their excellent heat resistance and light resistance. A phenyl silicone resin or a dimethyl silicone resin can be used as the base material of the first light-transmissive member 30, for example.

[0041] The first light-transmissive member 30 may contain a light-reflecting material. This makes it easier to adjust the light distribution characteristics of the light-emitting device 100. As the light-reflecting material, it is preferable to use a material that is less likely to absorb light from the light-emitting element 20 and has a large refractive index difference with respect to the base material. Examples of such light-reflecting materials include titanium oxide, zinc oxide, silicon oxide, zirconium oxide, aluminum oxide, and aluminum nitride. The first light-transmissive member 30 may also contain a wavelength converting material. This makes it easier to adjust the color of the light from the light-emitting device 100. The wavelength converting material contained in the first light-transmissive member 30 may be one type or multiple types. The phosphor contained in the first light-transmissive member 30 may be dispersed or unevenly distributed. A known phosphor can be used for the wavelength converting material. As the phosphor, an yttrium-aluminum-garnet phosphor (e.g., Y3(Al,Ga)5O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu3(Al,Ga)5O 12:Ce), terbium aluminum garnet phosphors (e.g., Tb3(Al,Ga)5O 12 :Ce), CCA-based phosphors (e.g., Ca 10 (PO4)6Cl2:Eu), SAE-based phosphors (e.g., Sr4Al 14 O 25 :Eu), chlorosilicate phosphors (e.g., Ca8MgSiO 16 Cl2:Eu), β-sialon phosphors (e.g., (Si,Al)3(O,N)4:Eu), α-sialon phosphors (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu), SLA-based phosphors (e.g., SrLiAlN:Eu), CASN-based phosphors (e.g., CaAlSiN:Eu), or SCASN-based phosphors (e.g., (Sr,Ca)AlSiN:Eu); fluoride-based phosphors such as KSF-based phosphors (e.g., KSiF:Mn), KSAF-based phosphors (e.g., K(Si,Al)F:Mn), or MGF-based phosphors (e.g., 3.5MgO·0.5MgF·GeO:Mn); phosphors having a perovskite structure (e.g., CsPb(F,Cl,Br,I)); or quantum dot phosphors (e.g., CdSe, InP, AgInS, or AgInSe).

[0042] (Light-blocking member 40) The light-shielding member 40 is a member that blocks light from the light-emitting element 20. The light-shielding member 40 has a lower transmittance at the peak wavelength of the light-emitting element 20 than the first light-transmissive member 30. The light-shielding member 40 has, for example, a transmittance of 40% or less at the peak wavelength of the light-emitting element 20. The light-shielding member 40 covers the upper surface 20S of the light-emitting element 20 via the first light-transmissive member 30. As a result, light traveling upward from the light-emitting element 20 is blocked by the light-shielding member 40, so that the light emitted from the light-emitting device 100 tends to have a large lateral component (X direction and / or Y direction). In a planar view, at least a portion of the light-emitting element 20 overlaps with the light-shielding member 40. It is preferable that the entirety of each light-emitting element 20 included in the light-emitting device 100 overlaps with the light-shielding member 40 in a planar view. This makes it easier to block light traveling upward from the light-emitting element 20. As a result, the light emitted from the light emitting device 100 tends to have a large lateral component. The light-blocking member 40 may reflect or absorb the light from the light emitting element 20. It is preferable that the light-blocking member 40 has reflectivity. In this way, the light from the light emitting element 20 is less likely to be absorbed by the light-blocking member 40, thereby improving the light extraction efficiency of the light emitting device 100.

[0043] As in the light-emitting device 100A shown in FIG. 7A, the upper surface of the first light-transmissive member 30 may be flat. Alternatively, as in the light-emitting device 100 shown in FIG. 2, the upper surface of the first light-transmissive member 30 may define a recess 35. When the upper surface of the first light-transmissive member 30 defines a recess 35 as shown in FIG. 2, it is preferable that the light-blocking member 40 be disposed within the recess 35. By doing so, when the vertical size of the light-emitting device 100 is the same, the vertical size (which may also be called thickness) of the light-blocking member 40 can be increased. Increasing the vertical size of the light-blocking member 40 improves the light-blocking properties of the light-blocking member 40. This makes it easier for the light-blocking member 40 to block light traveling upward from the light-emitting element 20. As shown in FIG. 2, in a cross-sectional view, the light-blocking member 40 preferably has a first side 41 that slopes outward toward the upper side. Light traveling upward from the light-emitting element 20 is reflected at the first side 41 and converted into light traveling laterally. This allows the light emitting device 100 to efficiently spread the light from the light emitting element 20 in the lateral direction.

[0044] As shown in FIGS. 2 and 7B , the first light-transmissive member 30 may have a third outer surface 33 connecting the recess 35 and the second outer surface 32. As shown in FIG. 2 , the third outer surface 33 may be exposed from the light-shielding member 40. This can improve the light extraction efficiency of the light-emitting device 100 compared to when the third outer surface 33 is covered by the light-shielding member 40. Alternatively, as in the light-emitting device 100B shown in FIG. 7B , the third outer surface 33 may be covered by the light-shielding member 40. This reduces the amount of light emitted upward, and the light-emitting device 100B can emit light with a larger lateral component compared to when the third outer surface 33 is exposed from the light-shielding member 40. In a plan view, the third outer surface 33 may surround the light-emitting element 20.

[0045] As in the light-emitting device 100 shown in FIG. 2, the first outer surface 31 and the second outer surface 32 may be connected. As shown in FIG. 2, the first outer surface 31 and the second outer surface 32 are connected, which facilitates the formation of the first light-transmissive member 30. The first light-transmissive member 30 may further include a fourth outer surface 34 connecting the first outer surface 31 and the second outer surface 32, as in the light-emitting device 100C shown in FIG. 7C. When the first light-transmissive member 30 includes the fourth outer surface 34, as in the light-emitting device 100C shown in FIG. 7C, it is preferable that the fourth outer surface 34 and the lower surface 10B of the support 10 are parallel to each other in a cross-sectional view. This configuration makes it easier to suppress variations in the length of the first outer surface 31 in the vertical direction (Z direction). For example, when the first outer surface 31 is formed by cutting the first light-transmissive member 30 along the dashed lines C3 and C4 shown in Fig. 8, even if the cutting position is shifted laterally, the fourth outer surface 34 extends parallel to the lower surface 10B of the support 10 in a cross-sectional view, which makes it easier to suppress variation in the length of the first outer surface 31 in the vertical direction (Z direction). By suppressing variation in the length of the first outer surface 31 in the vertical direction (Z direction), it is easier to suppress variation in the light distribution characteristics of the light-emitting device. In a plan view, the fourth outer surface 34 may surround the light-emitting element 20.

[0046] 2, in a cross-sectional view, the light-blocking member 40 may have a second side 42 facing the light-emitting element 20 and a third side 43 located on the opposite side of the second side 42. The second side 42 is preferably parallel to the horizontal direction (X direction and / or Y direction). In this way, even if the position at which the light-emitting element 20 is placed varies in the horizontal direction, the second side 42 being parallel to the horizontal direction can suppress variation in the light distribution of the light-emitting device.

[0047] The light-shielding member 40 may be made of a metal or a resin material containing a light-reflecting substance. When a resin material is used as the base material of the light-shielding member 40, the same resin material as that of the first light-transmissive member 30 can be used. Furthermore, as with the first light-transmissive member, titanium oxide, zinc oxide, silicon oxide, zirconium oxide, aluminum oxide, aluminum nitride, and the like can be used as the light-reflecting substance. The light-reflecting substance can be contained in a proportion of, for example, 10% by weight to 90% by weight of the resin material. The difference between the linear expansion coefficient of the base material of the first light-transmissive member 30 and the linear expansion coefficient of the base material of the light-shielding member 40 is not particularly limited, but is preferably within 30 ppm / °C. This prevents the light-shielding member 40 from peeling off from the first light-transmissive member 30. For example, when a phenyl silicone resin is used as the base material of the first light-transmissive member 30, the phenyl silicone resin may also be used as the base material of the light-shielding member 40. The first light-transmitting member 30 and the light-blocking member 40 may be in contact with each other, and a known adhesive member may be positioned between the first light-transmitting member 30 and the light-blocking member 40.

[0048] (Second translucent member 50) As shown in FIG. 2 , the light emitting device 100 may include a second light-transmissive member 50. The second light-transmissive member 50 is a member that is translucent to light from the light emitting element 20. The second light-transmissive member 50 is surrounded by a wall portion 12 and covers the light emitting element 20. The second light-transmissive member 50 and the light emitting element 20 may be in contact with each other, or may be separated from each other. In a plan view, at least a portion of the second light-transmissive member 50 overlaps with the light-blocking member 40. In a plan view, it is preferable that the entire second light-transmissive member 50 overlaps with the light-blocking member 40. This makes it easier to block light traveling upward from the light emitting element 20.

[0049] As shown in FIG. 2 , in a cross-sectional view, it is preferable that the length L1 of the second light-transmissive member 50 in the horizontal direction is greater than the length L2 of the second side 42 of the light-blocking member 40 in the horizontal direction and is smaller than the length L3 of the third side 43 of the light-blocking member 40 in the horizontal direction. Note that the length of the second light-transmissive member 50 in the horizontal direction is the maximum length of the second light-transmissive member 50 in the horizontal direction. Because the length L1 of the second light-transmissive member 50 in the horizontal direction is greater than the length L2 of the second side 42 of the light-blocking member 40 in the horizontal direction, light emitted from the second light-transmissive member 50 is less likely to be blocked by the light-blocking member 40. This improves the light extraction efficiency of the light emitting device 100. Because the length L1 of the second light-transmissive member 50 in the horizontal direction is smaller than the length L3 of the third side 43 of the light-blocking member 40, light emitted from the second light-transmissive member 50 and traveling upward is more likely to be blocked by the light-blocking member 40. As a result, the light emitted from the light emitting device 100 tends to have a large lateral component.

[0050] The second light-transmissive member 50 may contain a wavelength conversion member, similar to the first light-transmissive member 30. Including a wavelength conversion member in the second light-transmissive member 50 facilitates color adjustment of light from the light-emitting device 100. The second light-transmissive member 50 may contain one or more types of wavelength conversion members. The wavelength conversion members contained in the second light-transmissive member 50 may be dispersed or unevenly distributed. It is preferable that the wavelength conversion members contained in the second light-transmissive member 50 be unevenly distributed toward the light-emitting element 20. That is, it is preferable that the concentration of the wavelength conversion member is higher in the lower portion of the second light-transmissive member 50 than in the upper portion. This makes it easier to maintain a substantially uniform thickness in the portion of the second light-transmissive member 50 where the concentration of the wavelength conversion member is high, thereby making it easier to suppress color unevenness in the light from the light-emitting device. For example, during the manufacturing process, the wavelength conversion member can be unevenly distributed toward the light-emitting element 20 by settling the wavelength conversion member within the second light-transmissive member 50. When the first light-transmissive member 30 contains a wavelength conversion member, the concentration of the wavelength conversion member contained in the second light-transmissive member 50 is preferably higher than the concentration of the wavelength conversion member contained in the first light-transmissive member 30. Since the second light-transmissive member 50 is located closer to the light-emitting element 20 than the first light-transmissive member 30, a high concentration of the second light-transmissive member 50 allows light from the light-emitting element 20 to be efficiently applied to the wavelength conversion member. Furthermore, when the light-emitting device 100 includes the second light-transmissive member 50, the first light-transmissive member 30 does not need to contain a wavelength conversion member. When the first light-transmissive member 30 does not contain a wavelength conversion member, it becomes easier to extract light from the light-emitting element 20 from the first light-transmissive member 30 to the outside of the light-emitting device 100.

[0051] The base material of the second light-transmissive member 50 may be, for example, a resin material. The same resin material as that of the first light-transmissive member 50 may also be used as the base material of the second light-transmissive member 50. The difference in refractive index between the base material of the first light-transmissive member 30 and the base material of the second light-transmissive member 50 is preferably within 0.05. This prevents light from the light-emitting element 20 from being reflected or refracted at the interface between the first light-transmissive member 30 and the second light-transmissive member 50. This facilitates introduction of light from the light-emitting element 20 from the second light-transmissive member 50 into the first light-transmissive member 30, thereby improving the light extraction efficiency of the light-emitting device 100. Furthermore, the difference between the linear expansion coefficient of the base material of the first light-transmissive member 30 and the linear expansion coefficient of the base material of the second light-transmissive member 50 is not particularly limited, but is preferably within 30 ppm / °C. This prevents the first light-transmissive member 30 from peeling off from the second light-transmissive member 50. For example, when a phenyl silicone resin is used as the base material of the first light-transmissive member 30, a phenyl silicone resin may also be used as the base material of the second light-transmissive member 50.

[0052] As shown in FIG. 10 , in a cross-sectional view of the light-emitting device 100D, the upper surface 12S of the wall portion 12 preferably has an inclined surface 12S1 that slopes downward toward the outside. This configuration reduces the vertical (Z-direction) length S1 of the wall portion 12 at the outer edge of the light-emitting device 100D in a plan view. This facilitates increasing the vertical length S2 of the first light-transmissive member 30 at the outer edge of the light-emitting device 100D in a plan view, thereby improving the light extraction efficiency of the light-emitting device 100D. As shown in FIG. 9 , the first outer surface 31 of the first light-transmissive member 30 is located at the outer edge of the light-emitting device 100D in a plan view, making it easier to extract light with a large lateral component emitted from the light-emitting element 20 from the first outer surface 31 of the first light-transmissive member 30 to the outside of the light-emitting device 100D.

[0053] The length of the first outer surface 31 in the Z direction is not particularly limited. Preferably, the length of the first outer surface 31 in the Z direction is, for example, 0.7 to 1.3 times the length of the second outer surface 32 in the Z direction. When the length of the first outer surface 31 in the Z direction is 0.7 or more times the length of the second outer surface 32 in the Z direction, the area of ​​the first outer surface 31 can be increased. This makes it easier to extract light from the light-emitting element 20 to the outside through the first outer surface 31. When the length of the first outer surface 31 in the Z direction is 1.3 or less times the length of the second outer surface 32 in the Z direction, the area of ​​the second outer surface 32 can be increased. This makes it easier to control the light distribution characteristics of the light-emitting device by the second outer surface 32.

[0054] 11, it is preferable that the light emitting element 20 is surrounded by the inclined surface 12S1 in plan view, which makes it easier to extract light from the light emitting element 20.

[0055] 10, in a cross-sectional view, the maximum length L4 of the light-shielding member 40 in the horizontal direction is preferably greater than the shortest distance L5 between the pair of inclined surfaces 12S1 in the horizontal direction. This makes it easier for the light-shielding member 40 to block light traveling upward from the second light-transmissive member 50. As a result, the light emitted from the light-emitting device 100D tends to have a large horizontal component.

[0056] 12A, a first groove 15 (shown by hatching) is preferably provided on the upper surface of the first lead 14A so as to surround the mounting surface 11A on which the light emitting element 20 is mounted. The reflective resin member 13 disposed in the first groove 15 improves the light extraction efficiency of the light emitting device 100D. As shown in FIG. 12B, a second groove 16 (shown by hatching) is preferably provided on the lower surface of the first lead 14A and / or the second lead 14B.

[0057] 13A, the first light-transmissive member 30 may have a fourth outer surface 34 and a fifth outer surface 36 connecting the first outer surface 31 and the second outer surface 32 in a cross-sectional view. When the fourth outer surface 34 is provided as in the light-emitting device 100E shown in FIG. 13A, it is preferable that the fourth outer surface 34 and the lower surface 10B of the support body 10 are parallel to each other in a cross-sectional view. This makes it easier to suppress variations in the length of the first outer surface 31 in the up-down direction (Z direction).

[0058] In a cross-sectional view, the third angle θ3 formed between the fifth outer surface 36 and the lower surface 10B of the support 10 is preferably equal to or greater than the first angle θ1. This allows the first light-transmissive member 30 having the fifth outer surface 36 to be easily removed from a mold when the fifth outer surface 36 is formed using a mold. In this specification, the third angle θ3 is the angle formed between a plane including the fifth outer surface 36 and a plane including the lower surface 10B of the support 10. As shown in FIG. 13A , the third angle θ3 is an angle defined at the point where the plane including the fifth outer surface 36 intersects with the plane including the lower surface 10B of the support 10, and refers to an angle located above the lower surface 10B of the support and located farther from the center of the light-emitting device. The fifth outer surface 36 is, for example, inclined in a direction away from the center of the light-emitting device as it approaches the lower surface 10B of the support 10.

[0059] In a cross-sectional view, the third angle θ3 is preferably smaller than the second angle θ2. This makes it difficult for upwardly traveling light emitted from the light-emitting element 20 to hit the fifth outer surface 36. This makes it easier to extract light with a large lateral component from the fifth outer surface 36 to the outside of the light-emitting device 100E. The third angle θ3 is not particularly limited, but is preferably greater than 90° and equal to or less than 97°. When the third angle θ3 is greater than 90°, if the fifth outer surface 36 is formed using a mold, the first light-transmissive member 30 having the fifth outer surface 36 can be easily removed from the mold. When the third angle θ3 is equal to or less than 97°, it makes it easier to extract light with a large lateral component from the fifth outer surface 36 to the outside of the light-emitting device 100E.

[0060] As in the light-emitting device 100F shown in FIG. 13B , the light-shielding member 40 may have, in a cross-sectional view, a first side (interface) 41 that slopes outward toward the upper side and a fourth side (interface) 44 that connects a third side (interface) 43 located on the opposite side of a second side (interface) 42 that faces the light-emitting element 20. In a cross-sectional view, the fourth angle θ4 formed between the first side 41 and the second side 42 is preferably larger than the fifth angle θ5 formed between the fourth side 44 and the second side 42. This makes it easier for light traveling upward from the light-emitting element 20 to be reflected at the position of the first side 41. Furthermore, since the fifth angle θ5 formed between the fourth side 44 and the second side 42 is smaller than the fourth angle θ4 formed between the first side 41 and the second side 42, it is easier to suppress variation in the length of the light-shielding member 40 in the lateral direction (X direction and / or Y direction). In this specification, the fourth angle θ4 is the angle formed between a plane including the first side (interface) 41 and a plane including the second side (interface) 42. As shown in FIG. 13B, the fourth angle θ4 refers to an angle (i.e., an interior angle) inside the recess 35 and located above the second side (interface) 42. The fifth angle θ5 is the angle formed between a plane including the fourth side (interface) 44 and a plane including the second side (interface) 42. As shown in FIG. 13B, the fifth angle θ5 is an angle defined at the point where the plane including the fourth side (interface) 44 intersects with the plane including the second side (interface) 42, and refers to the angle located above the fourth side (interface) 44 that is closer to the center of the light-emitting device. The fourth side (interface) 44 inclines toward the center of the light-emitting device as it approaches the lower surface 10B of the support 10. A second side (interface) 42 of the light blocking member 40 shown in FIG. 13B extends in the horizontal direction (X direction).

[0061] When the light-shielding member 40 is a resin member containing a light-reflecting substance, the light-reflecting substance may be dispersed or unevenly distributed within the resin member. The light-reflecting substance contained in the light-shielding member 40 is preferably unevenly distributed on the bottom side of the recess 35. In other words, it is preferable that the concentration of the light-reflecting substance is higher in the lower portion of the light-shielding member 40 than in the upper portion. In this way, the light-shielding member 40 has a portion with a high concentration of the light-reflecting substance, which makes it easier for the light-shielding member 40 to block a portion of the light traveling upward from the light-emitting element 20.

[0062] As in the light-emitting device 100G shown in FIG. 14 , the lower surface of the first light-transmissive member 30, which faces the upper surface 20S of the light-emitting element 20, preferably has a convex portion 37. This makes it easier to increase the contact area between the first light-transmissive member 30 and the second light-transmissive member 50. This improves adhesion between the first light-transmissive member 30 and the second light-transmissive member 50. When the first light-transmissive member 30 and the second light-transmissive member 50 have different refractive indices, the convex portion 37 of the first light-transmissive member 30 makes it easier to control the light distribution characteristics of the light-emitting device 100G. When the first light-transmissive member 30 and the second light-transmissive member 50 have different refractive indices, light from the light-emitting element 20 is refracted at the interface between the first light-transmissive member 30 and the second light-transmissive member 50, changing its direction. By providing the first light-transmissive member 30 with the convex portions 37, the direction in which light from the light-emitting element 20 travels can be controlled by the convex portions 37 at the interface between the first light-transmissive member 30 and the second light-transmissive member 50. This makes it easier to control the light distribution characteristics of the light-emitting device 100G. Note that the lower surface of the first light-transmissive member 30 facing the upper surface 20S of the light-emitting element 20 may be provided with concave portions. This improves adhesion between the first light-transmissive member 30 and the second light-transmissive member 50. When the refractive indexes of the first light-transmissive member 30 and the second light-transmissive member 50 are different, the concave portions of the first light-transmissive member 30 make it easier to control the light distribution characteristics of the light-emitting device.

[0063] 15 , in a plan view, the first groove 15 does not have to be provided in a portion of the upper surface of the first lead 14A that is located between the first light-emitting element 20A and the second light-emitting element 20B. That is, the portion of the upper surface of the first lead 14A that is located between the first light-emitting element 20A and the second light-emitting element 20B may be exposed from the resin member 13. For example, when the reflectance of the first lead 14A for the peak wavelength of light of the first light-emitting element 20A and / or the second light-emitting element 20B is higher than that of the resin member 13, the portion of the upper surface of the first lead 14A that is located between the first light-emitting element 20A and the second light-emitting element 20B is exposed from the resin member 13, thereby improving the light extraction efficiency of the light-emitting device.

[0064] 16, a first groove 15 (shown by hatching) is preferably provided on the upper surface of the first lead 14A so as to surround the mounting surface 11A on which the first light-emitting element 20A and the second light-emitting element 20B are mounted. This improves adhesion between the resin member 13 and the first lead 14A. Since the resin member 13 is disposed within the first groove 15, providing the first groove 15 on the upper surface of the first lead 14A makes it possible to reduce the area of ​​the first lead 14A exposed from the resin member 13. This makes it possible to suppress sulfuration of the first lead 14A.

[0065] As in light-emitting device 100H shown in Fig. 17, one side of the rectangular outer edge of light-emitting element 20 may be parallel to the X direction or the Y direction in a plan view. In the example shown in Figs. 18 and 19, first light-emitting element 20A is mounted on first lead 14A, and second light-emitting element 20B is mounted on second lead 14B. In this case, as shown in Fig. 20, first groove 15 may be provided in the upper surface of first lead 14A so as to surround mounting surface 11A on which first light-emitting element 20A is mounted, and first groove 15 may be provided in the upper surface of second lead 14B so as to surround mounting surface 11A on which second light-emitting element 20B is mounted.

[0066] The surface light source 1000 shown in FIGS. 21 and 22 includes a plurality of light emitting devices 100D, a substrate 200, and at least one partitioning member 300. The plurality of light emitting devices 100D are disposed on the substrate 200. The at least one partitioning member 300 is disposed on the substrate 200. "Disposed on the substrate" includes both cases where a partitioning member or the like is disposed directly on the upper surface of the substrate, and cases where it is disposed indirectly via an adhesive member or the like. The light emitting device included in the surface light source 1000 is not limited to the light emitting device 100D. The surface light source 1000 can include any of the light emitting devices described above, such as the light emitting device 100.

[0067] (Substrate 200) The substrate 200 is a member on which a plurality of light emitting devices are placed. The substrate 200 includes a base material 200A and conductor wiring 200B disposed on the upper surface of the base material 200A. The conductor wiring 200B is electrically connected to the light emitting device 100D and supplies power to the light emitting device 100D. A portion of the conductor wiring 200B that is not electrically connected to the light emitting device 100D is preferably covered with a covering member 210.

[0068] The material of the substrate 200A may be any material that can insulate and separate at least one pair of conductor wirings 200B, and examples thereof include ceramics, resins, composite materials, etc. Examples of resins include phenolic resin, epoxy resin, polyimide resin, BT resin, polyphthalamide (PPA), polyethylene terephthalate (PET), etc. Examples of composite materials include the above-mentioned resins mixed with inorganic fillers such as glass fiber, silicon oxide, titanium oxide, and aluminum oxide, glass fiber reinforced resin (glass epoxy), and metal substrates in which a metal member is coated with an insulating layer.

[0069] The thickness of the substrate 200A can be selected appropriately. The substrate 200A may be either a rigid substrate or a flexible substrate that can be manufactured by a roll-to-roll method. The rigid substrate may be a thin, bendable rigid substrate. The material of the conductor wiring 200B is not particularly limited as long as it is a conductive member, and materials that are normally used for wiring layers of circuit boards and the like can be used.

[0070] The covering member 210 is preferably made of an insulating material. Examples of materials for the covering member 210 include the same materials as those exemplified as materials for the base material 200A. By using the above-mentioned resin containing a white light-reflective filler or a large number of bubbles as the covering member 210, the light emitted from the light-emitting device 100D is reflected, thereby improving the light extraction efficiency of the surface light source 1000.

[0071] (compartment member 300) The partitioning member 300 is a member that defines partitioned regions 330, which will be described later. One partitioned region 330 can be used as, for example, a unit of local dimming drive. The partitioning member 300 has a plurality of first partition wall portions 310 and a plurality of second partition wall portions 320. The first partition wall portion 310 has a first ridge line 311 extending in a first direction, a first partition sidewall 311A, and a second partition sidewall 311B. In FIG. 21 , the first direction is the Y direction. The first partition sidewall 311A ​​and the second partition sidewall 311B are arranged on either side of the first ridge line 311 in a plan view. The upper end of the first partition sidewall 311A ​​and the upper end of the second partition sidewall 311B are continuous. As shown in FIG. 22 , there is a space between the first partition sidewall 311A ​​and the second partition sidewall 311B.

[0072] The first ridge line 311 is a line connecting the highest points of the first partition wall portion 310. The area near the first ridge line 311 may have a pointed shape or a rounded shape in a cross section taken in a direction perpendicular to the first ridge line 311. The area near the first ridge line 311 may also have a shape in which a very narrow flat portion extends linearly.

[0073] The second compartment wall portion 320 has a second ridge line 321 extending in a second direction intersecting the first direction, a third compartment side wall 321A, and a fourth compartment side wall 321B. In FIG. 21 , the second direction is the X direction. However, the first direction and the second direction do not have to be orthogonal. The third compartment side wall 321A and the fourth compartment side wall 321B are disposed on either side of the second ridge line 321 in a plan view. The upper end of the third compartment side wall 321A and the upper end of the fourth compartment side wall 321B are continuous. There is a space between the third compartment side wall 321A and the fourth compartment side wall 321B.

[0074] The second ridge line 321 is a line connecting the highest points of the second partition wall portion 320. The area near the second ridge line 321 may have a pointed shape or a rounded shape in a cross section taken in a direction perpendicular to the second ridge line 321. The area near the second ridge line 321 may also have a shape in which a very narrow flat portion extends linearly.

[0075] The partitioned region 330 is an area surrounded by the first ridge line 311 and the second ridge line 321 in a plan view. A plurality of partitioned regions 330 are arranged in the first direction and the second direction. In FIG. 21, the plurality of partitioned regions 330 are arranged in a matrix with the first direction (Y direction) as the row direction and the second direction (X direction) as the column direction. A plurality of light emitting devices 100D are arranged within each partitioned region 330. It is preferable that the light emitting devices 100D arranged within each partitioned region 330 can be driven independently. In this way, one partitioned region 330 can be used as a unit of local dimming drive.

[0076] The compartment member 300 may have multiple compartment bottoms 340. The outer edges of the compartment bottoms 340 are connected to the lower ends of the first compartment sidewall 311A, the second compartment sidewall 311B, the third compartment sidewall 321A, and the fourth compartment sidewall 321B. In other words, the first compartment sidewall 311A, the second compartment sidewall 311B, the third compartment sidewall 321A, and the fourth compartment sidewall 321B are arranged to surround the compartment bottom 340 in a plan view. The first compartment sidewall 311A, the second compartment sidewall 311B, the third compartment sidewall 321A, and the fourth compartment sidewall 321B are inclined with respect to the compartment bottom 340.

[0077] As shown in FIG. 21 , the compartment bottom 340 has an opening 340H. The opening 340H is an area in which a light emitting device can be placed. The opening 340H is disposed, for example, in the center of the compartment bottom 340 and does not reach the lower ends of the first compartment sidewall 311A, the second compartment sidewall 311B, the third compartment sidewall 321A, and the fourth compartment sidewall 321B. The opening 340H is, for example, circular in plan view. The opening 340H may also be polygonal, such as triangular, rectangular, hexagonal, or octagonal.

[0078] 22, the compartment member 300 can be fixed onto the substrate 200 using an adhesive member 400. The adhesive member 400 may be, for example, a double-sided tape with an acrylic resin adhesive applied to both sides of a PET substrate, a hot-melt adhesive sheet, or a resin adhesive such as a thermosetting resin or a thermoplastic resin. These adhesive members preferably have high flame retardancy.

[0079] The partition member 300 preferably has light reflectivity, so that light from the light emitting device 100D can be efficiently reflected upward by the first partition sidewall 311A, the second partition sidewall 311B, the third partition sidewall 321A, the fourth partition sidewall 321B, and the partition bottom 340.

[0080] The partitioning member 300 may be molded using a resin containing a light-reflecting material such as titanium oxide, aluminum oxide, or silicon oxide. Alternatively, the partitioning member 300 may be molded using a resin that does not contain a light-reflecting material, and then a light-reflecting material may be provided on the surface. Alternatively, a resin containing a plurality of fine bubbles may be used. In this case, light is reflected at the interface between the bubbles and the resin. Examples of resins used for the partitioning member 300 include thermoplastic resins such as acrylic resin, polycarbonate resin, cyclic polyolefin resin, polyethylene terephthalate, polyethylene naphthalate, and polyester, and thermosetting resins such as epoxy resin and silicone resin. The partitioning member 300 preferably has a reflectance of 70% or more at the peak wavelength of light from the light-emitting device 100D.

[0081] The compartment member 300 may be formed by molding using a mold, photolithography, or the like, or the compartment member 300 having the first compartment wall portions 310, the second compartment wall portions 320, and the compartment bottom portions 340 may be purchased. Molding methods using a mold include injection molding, extrusion molding, compression molding, vacuum molding, and press molding. For example, by vacuum molding a reflective sheet made of PET or the like, a compartment member 300 in which the first compartment wall portions 310, the second compartment wall portions 320, and the compartment bottom portions 340 are integrally molded can be obtained.

[0082] 21 , the plurality of light emitting devices 100D includes a first light emitting device 101D and a second light emitting device 102D. The plurality of light emitting devices 100D may further include a third light emitting device 103D and a fourth light emitting device 104D. The first light emitting device 101D and the second light emitting device 102D are arranged side by side in the second direction. The third light emitting device 103D and the fourth light emitting device 104D are arranged side by side in the second direction. The first light emitting device 101D and the third light emitting device 103D are arranged side by side in the first direction. The second light emitting device 102D and the fourth light emitting device 104D are arranged side by side in the first direction.

[0083] 21 , in a plan view, first partition wall 310 is located between first light emitting device 101D and second light emitting device 102D. In a plan view, first partition side wall 311A ​​of first partition wall 310 is located between first light emitting device 101D and first ridge line 311. In a plan view, second partition side wall 311B of first partition wall 310 is located between second light emitting device 102D and first ridge line 311.

[0084] As shown in FIG. 22, the first compartment sidewall 311A ​​is inclined at an inclination angle α (0°<α<90°) with respect to the lower surface of the substrate 200. When the length in the second direction from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D is W1 and the length of the first compartment wall 310 in a third direction (Z direction) perpendicular to the first and second directions is W2, the inclination angle α preferably satisfies 2×arctan (2×W2 / W1)<α<3×arctan (2×W2 / W1). When the inclination angle α is greater than 2×arctan (2×W2 / W1), the size of the first compartment sidewall 311A ​​in the second direction can be easily reduced. This facilitates design, such as shortening the length W1 from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D. When the inclination angle α is smaller than 3×arctan(2×W2 / W1), the light traveling laterally from the first light emitting device 101D is more likely to be reflected upward by the first section sidewall 311A, thereby improving the light extraction efficiency of the surface light source 1000.

[0085] 22, the inclination angle α of the first compartment sidewall 311A ​​refers to the angle formed by an imaginary line connecting a point located on the first ridgeline 311 and a point P1 located on the first compartment sidewall 311A ​​where the length of the first compartment wall portion 310 in the third direction is half, and the lower surface of the substrate 200. In this specification, the center of the light-emitting device refers to the geometric center of gravity of the light-emitting device.

[0086] The length W1 in the second direction from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D is preferably 8 mm or more and 18 mm or less. By making the length W1 in the second direction from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D 8 mm or more, the number of light-emitting devices included in the surface light source can be reduced. This reduces the cost of the surface light source. By making the length W1 in the second direction from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D 18 mm or less, the area of ​​the partitioned region 330 can be reduced. This allows local dimming to be performed in a small partitioned region.

[0087] It is preferable that the length W2 in the third direction of first partition wall 310 is 0.2 to 0.3 times the length W1 in the second direction from the center of first light emitting device 101D to the center of second light emitting device 102D. When the length W2 in the third direction of first partition wall 310 is 0.2 or more times the length W1 in the second direction from the center of first light emitting device 101D to the center of second light emitting device 102D, light from first light emitting device 101D is more easily reflected by first partition wall 310. This makes it easier to improve the contrast ratio between the partitioned region where first light emitting device 101D is located and the partitioned region where second light emitting device 102D is located when first light emitting device 101D is lit and second light emitting device 102D is not lit. Since the length W2 in the third direction of the first partition wall portion 310 is 0.3 times or less the length W1 in the second direction from the center of the first light-emitting device 101D to the center of the second light-emitting device 102D, it becomes easier to make the surface light source 1000 smaller in the third direction.

[0088] As shown in Fig. 22, the surfaces of the first compartment side wall 311A ​​and / or the second compartment side wall 311B may be flat, or the surfaces of the first compartment side wall 311A ​​and / or the second compartment side wall 311B may be curved as in the planar light source 1001 shown in Fig. 23. Changing the shape of the first compartment side wall 311A ​​and / or the second compartment side wall 311B makes it easier to control the brightness unevenness of the planar light source.

[0089] It is preferable that the first compartment sidewall 311A ​​and the second compartment sidewall 311B are symmetrical with respect to a virtual line that passes through the first ridge line 311 and is parallel to the third direction (Z direction). This makes it easier to suppress uneven brightness in each compartment area. In this specification, it is assumed that symmetry is allowed to have a shape variation of ±3% or less.

[0090] The surface light source 1000 may include a third light-transmissive member that covers the first light-emitting device 101D and the substrate 200. By including the third light-transmissive member in the surface light source 1000, it becomes easier to control the light distribution characteristics of the first light-emitting device 101D, and therefore it is possible to suppress uneven brightness of the surface light source. The third light-transmissive member may cover the partition member 300. As a material for the third light-transmissive member, for example, the same material as that of the first light-transmissive member 30 can be used.

[0091] The surface light source 1002 shown in FIG. 24 includes a half mirror 501 disposed above the light-emitting device 100D. The half mirror 501 transmits a portion of the light from the light-emitting device 100D and reflects a portion of the light from the light-emitting device 100D toward the substrate 200. The reflectance of the half mirror 501 is preferably designed to be lower for oblique incidence than for perpendicular incidence. That is, the half mirror preferably has a high reflectance for light emitted from each light-emitting device parallel to the optical axis direction, and a characteristic in which the reflectance decreases as the radiation angle (the radiation angle parallel to the optical axis direction is considered to be 0 degrees) increases. This facilitates suppressing uneven brightness of the surface light source. For example, a dielectric multilayer film can be used for the half mirror. Using a dielectric multilayer film makes it possible to obtain a reflective film with low light absorption. The half mirror may have through-holes. The brightness of the surface light source can be easily controlled by the size, number, and position of the through-holes provided in the half mirror.

[0092] The surface light source 1002 shown in FIG. 24 includes a reflecting member 502 disposed above a half mirror 501. By disposing the reflecting member 502 in a location with high brightness, it becomes easier to suppress uneven brightness of the surface light source. In the surface light source 1002, the reflecting member 502 is disposed above each light-emitting device 100D and at a position overlapping each light-emitting device 100D in a planar view. The material of the reflecting member 502 can be, for example, a resin material containing a light-reflective substance. The resin material of the reflecting member 502 can be the same as that of the first light-transmissive member 30. The light-reflective substance of the reflecting member 502 can be the same as that of the first light-transmissive member 30.

[0093] The surface light source 1002 shown in FIG. 24 includes a light diffusion plate 503 disposed above a reflecting member 502. The light diffusion plate 503 diffuses incident light. The light diffusion plate 503 is made of a material that has low light absorption for visible light, such as polycarbonate resin, polystyrene resin, acrylic resin, or polyethylene resin. The light diffusion structure can be provided on the light diffusion plate 503 by, for example, providing an uneven surface on the light diffusion plate 503 or dispersing a material with a different refractive index in the light diffusion plate 503. A commercially available light diffusion plate known as a light diffusion sheet, diffuser film, or the like may be used as the light diffusion plate.

[0094] 24 includes a first prism sheet 504 and a second prism sheet 505 arranged above a light diffusion plate 503. The first prism sheet 504 and the second prism sheet 505 are components that change the traveling direction of light incident at an oblique angle to a vertical direction, thereby improving the brightness at the front. The first prism sheet 504 and the second prism sheet 505 can be made of polyethylene terephthalate or acrylic.

[0095] 24 includes a polarizing sheet 506 disposed above a second prism sheet 505. The polarizing sheet 506 is a member that aligns the polarization direction of the outgoing light by reflecting S-waves of the incident light and transmitting P-waves. In particular, when the surface light source 1002 is used as a backlight for a liquid crystal panel, it is preferable that the surface light source 1002 include the polarizing sheet 506.

[0096] The surface light source 1002 does not have to include all of the half mirror 501, the reflecting member 502, the light diffusion plate 503, the first prism sheet 504, the second prism sheet 505, and the polarizing sheet 506. In other words, the surface light source 1002 may include some of the half mirror 501, the reflecting member 502, the light diffusion plate 503, the first prism sheet 504, the second prism sheet 505, and the polarizing sheet 506. For example, the surface light source 1002 may not include the half mirror 501, but may include the reflecting member 502, the light diffusion plate 503, the first prism sheet 504, the second prism sheet 505, and the polarizing sheet 506.

[0097] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. All forms that can be implemented by a person skilled in the art through appropriate design modifications based on the above-described embodiments of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention. In addition, a person skilled in the art may conceive of various modifications and alterations within the scope of the concept of the present invention, and these modifications and alterations also fall within the scope of the present invention. [Industrial Applicability]

[0098] The light emitting device according to one embodiment of the present invention can be used as a variety of light sources, such as a light source for a liquid crystal backlight, a light source for illumination, a light source for an in-vehicle device, and a light source for a display. [Explanation of symbols]

[0099] 10 Support 11 Base 12 Wall 13 Resin parts 14A 1st Lead 14B 2nd lead 20 Light-emitting element 30 First translucent member 31 1st outer surface 32 Second outer surface 33 Third outer surface 40 Light-shielding member 50 Second translucent member 60 wire 100, 100A~100H Light-emitting device 200 boards 300 Compartment members 400 adhesive material 1000, 1001, 1002 Planar light source

Claims

1. a support having a wall; a light-emitting element placed on the support and surrounded by the wall portion in a plan view; a first light-transmissive member having a first outer surface and a second outer surface located above the first outer surface and located inside the first outer surface in a plan view, the first light-transmissive member covering the light-emitting element and the wall portion; a light-shielding member covering the first light-transmitting member; Equipped with In a cross-sectional view, the upper surface of the wall portion has an inclined surface that slopes downward toward the outside, The light emitting device, wherein the first outer surface and the second outer surface are exposed from the light-blocking member.

2. The light emitting device according to claim 1 , wherein a first angle formed between the first outer surface and the lower surface of the support is smaller than a second angle formed between the second outer surface and the lower surface of the support.

3. The light emitting device according to claim 1 , wherein the first outer surface and an outer surface of the wall portion are flush with each other.

4. an upper surface of the first light-transmissive member defining a recess; The light emitting device according to claim 1 , wherein the light blocking member is disposed within the recess.

5. The light emitting device according to claim 1 , wherein the light blocking member has a first side that slopes outwardly toward the upper side in a cross-sectional view.

6. a second light-transmitting member that is surrounded by the wall portion and covers the light-emitting element; In a cross-sectional view, the light-blocking member has a second side facing the light-emitting element and a third side located on the opposite side to the second side, 6. The light emitting device according to claim 1, wherein, in a cross-sectional view, the horizontal length of the second light-transmissive member is greater than the horizontal length of the second side and less than the horizontal length of the third side.

7. The light emitting device according to claim 6 , wherein the second light-transmissive member entirely overlaps the light-blocking member in a plan view.

8. The light emitting device according to claim 1 , wherein the light emitting element entirely overlaps the light blocking member in a plan view.

9. A plurality of light emitting devices according to any one of claims 1 to 8; a substrate on which the plurality of light emitting devices are disposed; At least one partition member disposed on the substrate; Equipped with The partition member is a plurality of first partition wall portions each having a first ridge line extending in a first direction; a plurality of second partition wall portions each having a second ridge line extending in a second direction intersecting the first direction; and In a plan view, a plurality of partitioned areas surrounded by the first ridge line and the second ridge line are arranged in the first direction and the second direction, The plurality of light emitting devices are each disposed within the partitioned area.

10. the plurality of light emitting devices include a first light emitting device and a second light emitting device arranged side by side in the second direction, the first partition wall portion has a first partition side wall and a second partition side wall disposed on either side of the first ridge line, the first compartment sidewall is located between the first light-emitting device and the first ridge line in a plan view; the first compartment sidewall is inclined at an inclination angle α greater than 0° and less than 90° with respect to the lower surface of the substrate; When a length in the second direction from the center of the first light-emitting device to the center of the second light-emitting device is defined as W1, and a length of the first partition wall portion in a third direction perpendicular to the first direction and the second direction is defined as W2, The surface light source according to claim 9, wherein the inclination angle α satisfies the relationship 2×arctan(2×W2 / W1)<α<3×arctan(2×W2 / W1).

11. The surface light source according to claim 10 , wherein a length in the second direction from a center of the first light emitting device to a center of the second light emitting device is 8 mm or more and 18 mm or less.

12. 12. The surface light source according to claim 10, wherein the length of the first partition wall portion in the third direction is 0.2 to 0.3 times the length in the second direction from the center of the first light-emitting device to the center of the second light-emitting device.

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