Light emitting device

Abstract

To provide a light emitting device with excellent heat dissipation.SOLUTION: A light emitting device in accordance with one embodiment of the present disclosure comprises a substrate, a light source arranged on the substrate, a lens arranged above the light source, and a spacer arranged between the substrate and the lens and containing a metal, and in the top view, the outer edge of the spacer is located outside the outer edge of the lens.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a light emitting device. [Background technology]

[0002] Conventionally, light emitting devices having light emitting elements such as LEDs (Light Emitting Diodes) are known. For example, Patent Document 1 discloses a light emitting device including a substrate, a light source, and a lens disposed above the substrate and facing the light source. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2019-523964 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a light emitting device with excellent heat dissipation properties. [Means for solving the problem]

[0005] An embodiment of a light emitting device according to the present disclosure comprises a substrate, a light source disposed on the substrate, a lens disposed above the light source, and a spacer containing a metal disposed between the substrate and the lens, wherein, in a top view, an outer edge of the spacer is positioned outside the outer edge of the lens. Effect of the Invention

[0006] According to an embodiment of the present disclosure, a light emitting device with excellent heat dissipation properties can be provided. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a schematic top view showing a lens and a spacer in the light emitting device according to the embodiment. [Diagram 2] 1 is a schematic cross-sectional view of a light emitting device according to an embodiment. [Diagram 3] 5A and 5B are schematic diagrams for explaining an example of a heat dissipation effect in a spacer of the light emitting device according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, the light-emitting device according to the embodiment of the present disclosure will be described in detail with reference to the drawings. However, the following embodiments are merely illustrative of the light-emitting device for embodying the technical ideas of the embodiments, and are not limited to the following. Furthermore, the dimensions, materials, shapes, and relative arrangements of the components described in the embodiments are merely illustrative examples, and are not intended to limit the scope of the present disclosure, unless otherwise specified. The size, positional relationship, etc. of the components shown in each drawing may be exaggerated to clarify the explanation. In the following explanation, the same names and symbols indicate the same or homogeneous components, and detailed explanations will be omitted as appropriate. An end view showing only a cut surface may be used as a cross-sectional view.

[0009] In the figures shown below, directions may be indicated by the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis are mutually orthogonal directions. The direction in which the arrow points in the X-axis direction is indicated as the +X direction, and the opposite direction of the +X direction is indicated as the -X direction. The direction in which the arrow points in the Y-axis direction is indicated as the +Y direction, and the opposite direction of the +Y direction is indicated as the -Y direction. The direction in which the arrow points in the Z-axis direction is indicated as the +Z direction, and the opposite direction of the +Z direction is indicated as the -Z direction. In addition, the term "top view" in the embodiments refers to viewing the object from the +Z direction. However, these do not limit the orientation of the light-emitting device when used, and the orientation of the light-emitting device is arbitrary. In addition, in the embodiments, the surface on the +Z direction side (i.e., the surface of the object when viewed from the +Z direction) is referred to as the "top surface," and the surface on the -Z direction side (i.e., the surface of the object when viewed from the -Z direction) is referred to as the "bottom surface." In the embodiments shown below, "along the X-axis, Y-axis, and Z-axis" includes the object having an inclination within a range of ±10° with respect to these axes. In addition, in the embodiment, the orthogonal angle may have an error of within ±10° with respect to 90°.

[0010] Furthermore, in this disclosure, unless otherwise specified, polygons such as rectangles are referred to as polygons, including shapes in which the corners of the polygons have been processed, such as by rounding, chamfering, removing the corners, or rounding off. Shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle parts of the sides are also referred to as polygons. In other words, shapes in which partial processing has been applied while leaving the polygon as the base are included in the interpretation of "polygon" described in this disclosure.

[0011] The same applies not only to polygons, but also to terms expressing specific shapes such as trapezoids, circles, and irregular shapes. The same also applies to terms relating to the sides that form the shapes. In other words, even if the corners or middle part of a side are processed, the interpretation of "side" includes the processed parts.

[0012] [Embodiment] <Example of Overall Configuration of Light-Emitting Device 1> The overall configuration of a light emitting device 1 according to an embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic top view showing a lens 30 and a spacer 40 in the light emitting device 1 according to the embodiment. Fig. 2 is a schematic cross-sectional view of the light emitting device 1 according to the embodiment.

[0013] As an example, the light emitting device 1 is a light emitting device for a flash in an imaging device provided in a smartphone. Examples of the imaging device include a camera that captures still images and a video camera that captures moving images. The light emitting device 1 is accommodated in the housing of the smartphone together with the imaging device.

[0014] The light emitting device 1 includes a substrate 10, a light source 20 disposed on the substrate 10, a lens 30 disposed above the light source 20, and a spacer 40 containing a metal disposed between the substrate 10 and the lens 30. In a top view, the outer edge of the spacer 40 is located outside the outer edge of the lens 30. The light emitting device 1 may further include a support member 50 that supports the lens 30 and the spacer 40 on the outer periphery of the substrate 10. The light emitting device 1 may also include other components such as electronic components mounted on the substrate 10 and a cover lens 60 that covers the lens 30, in addition to the light source 20. Examples of electronic components mounted on the substrate 10 include a photosensor, a Zener diode, a thermistor, and a capacitor. When the light emitting device 1 is a light emitting device for a flash in an imaging device, the light source 20 emits light in response to the imaging operation of the imaging device. The light emitting device 1 mounted on a smartphone can also be used as a torch light.

[0015] <Substrate 10> The structure of the substrate 10 will be described. The substrate 10 is a plate-like member having a substantially circular outer shape when viewed from above. However, the substrate 10 may have other outer shapes, such as a substantially elliptical, substantially rectangular, or substantially polygonal, when viewed from above.

[0016] 2, the substrate 10 has an upper surface 10a, a lower surface 10b, and one or more side surfaces 10c connecting the outer edges of the upper surface 10a and the lower surface 10b. The substrate 10 has a base 11, upper surface wiring 12, lower surface wiring 13, and inner layer wiring 14.

[0017] The base 11 corresponds to the base material of the substrate 10 and is a plate-like member having a substantially circular outer shape in top view. However, the base 11 may have other outer shapes such as a substantially elliptical, substantially rectangular, or substantially polygonal shape in top view. The base 11 supports the upper surface wiring 12, the lower surface wiring 13 (13a, 13b), and the inner layer wiring 14 (14a, 14b). The base 11 is preferably made of ceramics with excellent heat dissipation properties such as aluminum nitride, aluminum oxide, silicon carbide, silicon nitride, or resin with excellent heat dissipation properties such as glass epoxy. However, the material constituting the base 11 is not limited to these.

[0018] The upper surface wiring 12 is exposed from the base 11 and disposed on the upper surface 10a side of the substrate 10. The upper surface wiring 12 shown in FIG. 2 is disposed on the base 11. The lower surface wiring 13 (13a, 13b) is disposed on the lower surface 10b side of the substrate 10. The inner layer wiring 14 (14a, 14b) is a wiring that penetrates the base 11 and electrically connects the upper surface wiring 12 and the lower surface wiring 13. The upper surface wiring 12, the lower surface wiring 13 (13a, 13b), and the inner layer wiring 14 (14a, 14b) can be made of a metal material, and for example, a single metal such as gold (Au), silver (Ag), aluminum (Al), nickel (Ni), rhodium (Rh), copper (Cu), titanium (Ti), platinum (Pt), palladium (Pd), molybdenum (Mo), chromium (Cr), tungsten (W), or an alloy containing these metals can be suitably used. However, the materials constituting the upper surface wiring 12, the lower surface wiring 13, and the inner layer wiring 14 are not limited to these.

[0019] The upper surface wiring 12 includes connection parts 121a, 121b and a heat dissipation part 122, which are respectively disposed at different positions on the upper surface 10a of the substrate 10. On the upper surface 10a of the substrate 10, the connection parts 121a, 121b and the heat dissipation part 122 are disposed separately from each other. It is preferable that the connection parts 121a, 121b and the heat dissipation part 122 are not electrically connected. Since the heat dissipation part 122 is disposed in contact with the spacer 40 containing metal, when the heat dissipation part 122 is electrically connected to the connection parts 121a, 121b, electricity flows through the spacer 40, and electricity may flow unintentionally to components in the housing via the spacer 40.

[0020] The connection portions 121a and 121b are electrically connected to the light source 20. Specifically, as shown in Fig. 2, an upper surface of the connection portion 121a is joined to a lower surface of a first electrode 211 of the light emitting element 21 included in the light source 20. An upper surface of the connection portion 121b is joined to a lower surface of a second electrode 212 of the light emitting element 21 included in the light source 20. The upper surface of the connection portion 121a and the lower surface of the first electrode 211, and the upper surface of the connection portion 121b and the lower surface of the second electrode 212 can be joined via a conductive joining member.

[0021] The upper surface of the heat dissipation section 122 is joined to the lower surface 40b of the spacer 40. For example, heat generated during the light emission operation of the light source 20 is transferred to the substrate 10 and then dissipated from the spacer 40 through the heat dissipation section 122. The heat dissipation section 122 has an annular shape and is provided continuously along the outer edge of the substrate 10. However, the heat dissipation section 122 may have a shape other than annular as long as it is joined to the spacer 40.

[0022] The bottom surface wirings 13a and 13b are conductor patterns arranged on the substrate 10 at a position opposite to the position at which the top surface wiring 12 is provided.

[0023] The bottom wiring 13a, 13b is connected to an external power source. The bottom wiring 13a, 13b serve as external connection terminals in the light emitting device 1. The bottom wiring 13a is preferably disposed at a position overlapping the connection portion 121a when viewed from above. The bottom wiring 13b is preferably disposed at a position overlapping the connection portion 121b when viewed from above. This ensures a heat dissipation path directly below the light source 20 via the bottom wiring 13a, 13b.

[0024] The inner layer wirings 14a and 14b are, for example, conductor portions provided in vias or the like that penetrate the base 11 in the Z direction.

[0025] It is preferable that the inner layer wiring 14a overlaps with the connection portion 121a and the bottom wiring 13a in a top view. The inner layer wiring 14a is electrically connected to the connection portion 121a and the bottom wiring 13a. As a result, the first electrode 211 of the light emitting element 21 is electrically connected to an external power source through the connection portion 121a, the inner layer wiring 14a, and the bottom wiring 13a.

[0026] It is preferable that the inner layer wiring 14b overlaps with the connection portion 121b and the bottom wiring 13b in a top view. The inner layer wiring 14b is electrically connected to the connection portion 121b and the bottom wiring 13b. As a result, the second electrode 212 of the light emitting element 21 is electrically connected to an external power source through the connection portion 121b, the inner layer wiring 14b, and the bottom wiring 13b.

[0027] <Light source 20> Next, the configuration of the light source 20 will be described. The light source 20 is disposed on the substrate 10. The light source 20 is disposed in the center of the substrate 10 so that the center of the light source 20 intersects with the optical axis of the lens 30 when viewed from above. The light source 20 has a substantially rectangular outer shape when viewed from above. However, the light source 20 may have other outer shapes, such as a substantially circular shape, a substantially elliptical shape, or a substantially polygonal shape, when viewed from above.

[0028] 2, the light source 20 includes a light emitting element 21 and a wavelength conversion member 22. The light source 20 may further include other components such as a light blocking member surrounding at least the side surface of the light emitting element 21. The light source 20 emits white light. However, the light emitted by the light source 20 is not limited to white light, and may be light having a specific wavelength such as blue. In addition, the wavelength and chromaticity of the light emitted by the light source 20 may be appropriately selected depending on the use of the light emitting device 1.

[0029] The light emitting element 21 is a semiconductor light emitting element such as an LED or an LD (Laser Diode). The light emitting element 21 has a rectangular outer shape when viewed from above. However, the light emitting element 21 may have other outer shapes such as a substantially circular, substantially elliptical, or substantially polygonal shape.

[0030] The light emitting element 21 includes a first electrode 211, a second electrode 212, and a light emitting portion 213. The first electrode 211 and the second electrode 212 are disposed at different positions on the lower surface side of the light emitting element 21. When the light source 20 performs a light emitting operation, power from an external power source is supplied to the light emitting portion 213 via the first electrode 211 and the second electrode 212.

[0031] The light emitting section 213 includes an n-type semiconductor layer, an active layer, and a p-type semiconductor layer, which are stacked in this order in the Z direction. The light emitting section 213 emits, for example, blue light. Each of the n-type semiconductor layer, the active layer, and the p-type semiconductor layer in the light emitting section 213 is made of, for example, In X Al Y Ga 1-X-Y It is composed of nitride semiconductors such as N (0≦X, 0≦Y, X+Y≦1).

[0032] The emission peak wavelength of the light emitting section 213 is preferably 400 nm or more and 530 nm or less, more preferably 420 nm or more and 490 nm or less, and even more preferably 450 nm or more and 475 nm or less, from the viewpoint of the excitation efficiency of the wavelength conversion member 22. However, the emission peak wavelength of the light emitting section 213 is not limited thereto.

[0033] The wavelength conversion member 22 is disposed on the light emitting element 21. The wavelength conversion member 22 is a plate-like member having a rectangular outer shape in a top view. However, the wavelength conversion member 22 may have other outer shapes such as a substantially circular shape, a substantially elliptical shape, or a substantially polygonal shape.

[0034] The wavelength conversion member 22 includes a wavelength conversion layer that converts the wavelength of light emitted by the light emitting element 21, and a light diffusion layer disposed on the wavelength conversion layer. The upper surface of the light diffusion layer corresponds to the upper surface of the light source 20. In other words, the upper surface of the light diffusion layer corresponds to the light extraction surface of the light source 20.

[0035] The wavelength conversion layer of the wavelength conversion member 22 includes a base material containing a light-transmitting material, and the wavelength conversion material contained in the base material. Here, "light-transmitting" means that 60% or more of the light emitted by the light-emitting element 21 is transmitted. Examples of the light-transmitting material include resin, ceramics, and glass. Examples of the resin include silicone resin, silicone-modified resin, epoxy resin, epoxy-modified resin, and phenol resin. In particular, silicone resin or modified resin thereof, which has excellent light resistance and heat resistance, is preferable. However, the light-transmitting material is not limited to these.

[0036] The wavelength conversion material contained in the wavelength conversion layer can be, for example, phosphor particles. The phosphor can be an yttrium-aluminum-garnet phosphor (e.g., (Y,Gd) 3 (Al,Ga) 5 O 12 :Ce), lutetium aluminum garnet phosphors (e.g., Lu 3 (Al,Ga) 5 O 12:Ce), terbium-aluminum-garnet-based phosphor (e.g., Tb 3 (Al,Ga) 5 O 12 :Ce), CCA-based phosphor (e.g., Ca 10 (PO 4 ) 6 Cl 2 :Eu), SAE-based phosphor (e.g., Sr 4 Al 14 O 25 :Eu), chlorosilicate-based phosphor (e.g., Ca 8 MgSi 4 O 16 Cl 2 :Eu), silicate-based phosphor (e.g., (Ba,Sr,Ca,Mg) 2 SiO 4 :Eu), β-sialon-based phosphor (e.g., (Si,Al) 3 (O,N) 4 :Eu) or α-sialon-based phosphor (e.g., Ca(Si,Al) 12 (O,N) 16 :Eu) and other oxynitride-based phosphors, LSN-based phosphor (e.g., (La,Y) 3 Si 6 N 11 :Ce), BSESN-based phosphor (e.g., (Ba,Sr) 2 Si 5 N 8 :Eu), SLA-based phosphor (e.g., SrLiAl 3 N 4 :Eu), CASN-based phosphor (e.g., CaAlSiN 3 :Eu) or SCASN-based phosphor (e.g., (Sr,Ca)AlSiN 3 :Eu) and other nitride-based phosphors, KSF-based phosphor (e.g., K 2 SiF 6 :Mn), KSAF-based phosphor (e.g., K 2 (Si 1-x Al x )F 6-x :Mn Here, x satisfies 0 < x < 1.) or MGF-based phosphor (e.g., 3.5MgO·0.5MgF 2 ·GeO 2Fluoride-based phosphors such as (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I) and quantum dots with perovskite structures such as (Cs,FA,MA)(Pb,Sn)(F,Cl,Br,I) 3 Here, FA and MA represent formamidinium and methylammonium, respectively.), II-VI group quantum dots (e.g., CdSe), III-V group quantum dots (e.g., InP), or quantum dots having a chalcopyrite structure (e.g., (Ag,Cu)(In,Ga)(S,Se) 2 ) etc. can be used.

[0037] The light diffusion layer of the wavelength conversion member 22 is disposed on the wavelength conversion layer. The light diffusion layer includes a base material containing a light-transmitting material, and a light diffusion material dispersed in the base material. The light-transmitting material constituting the base material of the light diffusion layer may be the same type of material as the light-transmitting material constituting the base material of the wavelength conversion layer, or may be a different type of material. For example, the light-transmitting material constituting the base material of the light diffusion layer includes a silicone resin. However, the light-transmitting material is not limited to this.

[0038] The light diffusing material of the light diffusing layer diffuses the light emitted from the wavelength conversion layer. Examples of the light diffusing material include titanium oxide, barium titanate, aluminum oxide, and silicon oxide. However, the light diffusing material is not limited to these.

[0039] Furthermore, the wavelength conversion member 22 may have a molded body of a light-transmitting material such as resin, ceramics, glass, etc. as a support for supporting the wavelength conversion layer and / or the light diffusion layer.

[0040] <Lens 30> The lens 30 is disposed above the light source 20 and is an optical member that transmits light from the light source 20. The lens 30 has a substantially circular outer shape when viewed from above. However, the lens 30 may have other outer shapes, such as a substantially rectangular, substantially elliptical, or substantially polygonal shape, when viewed from above.

[0041] Examples of materials constituting the lens 30 include light-transmitting resins and optical glasses. Examples of light-transmitting resins include thermoplastic resins such as polycarbonate, acrylic, cyclic polyolefin, polyethylene terephthalate, and polyester, and thermosetting resins such as phenol resin, urea resin, melamine resin, epoxy resin, silicone resin, and polyurethane.

[0042] 2, the lens 30 includes a lens portion 31 and a lens holding portion 32 that is disposed outside the lens portion 31 and holds the lens portion 31. The lens holding portion 32 is continuous with the outer edge of the lens portion 31 and is formed integrally with the lens portion 31.

[0043] The lens portion 31 is, for example, a biconvex lens. However, the lens portion 31 may be a lens having another form, such as a plano-convex lens, a convex meniscus lens, a biconcave lens, a plano-concave lens, a concave meniscus lens, or a Fresnel lens.

[0044] The lens portion 31 having a biconvex lens shape has a first convex surface 311 that protrudes in a direction toward the light source 20 (-Z direction), and a second convex surface 312 that protrudes in a direction opposite to the direction toward the light source 20 (+Z direction). Light emitted from the light source 20 enters the first convex surface 311, passes through the lens portion 31, and exits from the second convex surface 312. The curvature of the first convex surface 311 and the curvature of the second convex surface 312 may be the same as or different from each other. When viewed from above, the second convex surface 312 preferably has a size that includes the light source 20.

[0045] 2, the lower surface of the outer periphery 321 of the lens holding part 32 is provided with a protrusion 322 that is convex in the direction toward the spacer 40 (the -Z direction side). In top view, the protrusion 322 has an annular shape that follows the outer periphery of the lens part 31. However, the protrusion 322 may have another outer shape.

[0046] The protrusion 322 is accommodated in a step portion 41 recessed downward from the upper surface of the spacer 40. This allows the lens 30 to be supported by the step portion 41. The lower surface of the outer periphery 321 of the lens holding part 32 corresponds to the lowermost planar area of ​​the lens 30. Therefore, the lower surface of the outer periphery 321 of the lens holding part 32 will be referred to as the "lower surface of the lens 30" hereinafter.

[0047] <Spacer 40> Next, a configuration of the spacer 40 will be described. As shown in Fig. 2, the spacer 40 is disposed between the substrate 10 and the lens 30. By disposing the spacer 40 between the substrate 10 and the lens 30, a hollow space S1 for accommodating the light source 20 is formed.

[0048] The spacer 40 includes a metal. The metal included in the spacer 40 is preferably copper or aluminum, which have excellent heat dissipation properties. However, the metal included in the spacer 40 is not limited to these. When the spacer 40 disposed between the substrate 10 and the lens 30 includes a metal with excellent heat dissipation properties, heat generated during the light emission operation of the light source 20 can be efficiently dissipated to the external space via the substrate 10 and the spacer 40.

[0049] The spacer 40 has an annular shape surrounding the light source 20 in a top view. Specifically, the spacer 40 has an upper surface 40a, a lower surface 40b, an inner surface 40c connecting the inner edges of the upper surface 40a and the lower surface 40b, and an outer surface 40d connecting the outer edges of the upper surface 40a and the lower surface 40b. By making the spacer 40 an annular member surrounding the light source 20 in a top view, heat in the hollow space S1 that houses the light source 20 can be dissipated to the external space through the spacer 40. However, the spacer 40 may have a shape other than annular in a top view. The spacer 40 may be disposed between the substrate 10 and the lens 30 and may have a shape that forms the hollow space S1 that houses the light source 20. In addition, the spacer 40 is not limited to a series of members that have an annular shape in a top view. For example, the spacer 40 may be a combination of two or more plate-like members that are disposed so as to sandwich the light source 20 in a top view.

[0050] In top view, the outer edge of the spacer 40 is located outside the outer edge of the lens 30. Specifically, in top view, the outer side surface 40d of the spacer 40 is located outside the outer edge of the lens holding portion 32 of the lens 30. Therefore, of the upper surface 40a of the spacer 40, a region outside the outer edge of the lens 30 is exposed to the external space. As a result, each of the outer side surface 40d of the spacer 40 and the outer region of the upper surface 40a can be brought into contact with the external space, thereby improving the heat dissipation efficiency of the spacer 40.

[0051] The lower surface 40b of the spacer 40 and the upper surface 10a of the substrate 10 may be connected via a bonding member, or may be directly bonded without a bonding member. In particular, direct bonding is preferable from the viewpoint of heat dissipation. Here, "direct bonding" refers to a state in which objects are bonded to each other without a bonding member such as an adhesive, for example, by using a surface activated bonding method, an atomic diffusion bonding method, or the like. Specifically, the lower surface 40b of the spacer 40 and the upper surface of the heat dissipation section 122 arranged on the upper surface 10a of the substrate 10 are directly bonded. By directly bonding the lower surface 40b of the spacer 40 and the upper surface of the heat dissipation section 122, the heat of the light source 20 generated during the light emission operation can be dissipated to the external space through the substrate 10 and the spacer 40 without a decrease in heat dissipation efficiency at the boundary between the spacer 40 and the heat dissipation section 122. Therefore, the heat dissipation efficiency of the spacer 40 can be further improved. Furthermore, by directly bonding the lower surface 40b of the spacer 40 to the upper surface of the heat dissipation portion 122, the bonding strength between the spacer 40 and the substrate 10 can be increased.

[0052] The lower surface 40b of the spacer 40 may include a metal film of the same type as the heat dissipation portion 122. For example, the metal film of the lower surface 40b of the spacer 40 may be directly bonded to the upper surface of the heat dissipation portion 122. By directly bonding the same type of metal films to each other, the bonding strength between the spacer 40 and the substrate 10 can be further increased without decreasing the heat dissipation efficiency.

[0053] The upper surface 40a of the spacer 40 and the lower surface of the lens 30 may be connected via a bonding member, or may be directly bonded without a bonding member. The spacer 40 and the lens 30 may be bonded by fitting the protrusion 322 of the lens 30 and the step portion 41 of the spacer 40 together.

[0054] The upper surface 40a of the spacer 40 may be provided with a metal film, similar to the lower surface 40b. The lower surface of the lens 30 may be provided with the same type of metal film as the metal film provided on the upper surface 40a of the spacer 40. Furthermore, the metal film provided on the upper surface 40a of the spacer 40 and the metal film provided on the lower surface of the lens 30 may be directly bonded to each other. By directly bonding the same type of metal films to each other, the bonding strength between the spacer 40 and the lens 30 can be further increased without decreasing the heat dissipation efficiency.

[0055] The inner side surface 40c of the spacer 40 has a tapered cross-sectional shape in which the width of the opening defined by the inner side surface 40c narrows as it approaches the substrate 10. That is, the inner side surface 40c is inclined so that the normal line of the inner side surface 40c intersects with the lens portion 31. In addition, the inner side surface 40c is preferably provided with a reflective film 45. The reflective film 45 reflects, toward the lens 30, light emitted by the light source 20 and directed toward the outside of the lens 30. This can increase the amount of light incident from the light source 20 to the lens portion 31. That is, the light extraction efficiency of the light emitting device 1 can be increased. The inner side surface 40c of the spacer 40 is not limited to the above shape. For example, the inner side surface 40c of the spacer 40 may have a cross-sectional shape that is approximately perpendicular to the upper surface of the substrate 10.

[0056] The reflective film 45 may be provided on a part of the inner surface 40c, but is preferably provided over the entire inner surface 40c. By providing the reflective film 45 over the entire inner surface 40c, the side surface of the light source 20 can be surrounded by the reflective film 45. As a result, more light can be reflected toward the lens 30.

[0057] Examples of the reflective film 45 include a metal film such as an aluminum film, and a dielectric multilayer film such as a DBR (Distributed Bragg Reflector). However, the configuration of the reflective film 45 is not limited to these. The reflective film 45 may be another optical thin film having a light reflecting function.

[0058] A plurality of fins 47 are provided on the outer side surface 40d of the spacer 40. By providing a plurality of fins 47 on the outer side surface 40d of the spacer 40, the surface area of ​​the outer side surface 40d in contact with the external space can be increased. As a result, the heat dissipation efficiency of the spacer 40 can be further improved.

[0059] 2, the spacer 40 may further include a step portion 41 continuing to each of the inner side surface 40c and the upper surface 40a. As an example, the step portion 41 has a first surface 411 extending horizontally from the upper end (the end on the +Z direction side) of the inner side surface 40c, and a second surface 412 perpendicular to the outer edge of the first surface 411 and reaching the upper surface 40a.

[0060] When the lens 30 is fixed to the spacer 40, the protrusion 322 provided on the lower surface of the lens 30 is accommodated in a recess formed by the step portion 41. At this time, it is preferable that each of the first surface 411 and the second surface 412 of the step portion 41 contacts the protrusion 322. This reduces the movement of the lens 30 by the step portion 41. As a result, the positional deviation of the lens 30 can be reduced via the step portion 41. This makes it easier to align the optical axis of the lens 30 with the optical axis of the light source 20.

[0061] <Support member 50> Next, the configuration of the support member 50 will be described. The light emitting device 1 may include a support member 50 arranged on the outer periphery of the substrate 10. As shown in FIG. 2, the support member 50 is arranged directly below the spacer 40. The support member 50 has an annular shape surrounding the substrate 10 in a top view. The space inside the annular support member 50 corresponds to the arrangement space of the substrate 10. When the substrate 10 is arranged in the space inside the support member 50, the side surface 10c of the substrate 10 and the inner surface of the support member 50 are joined. The support member 50 may have a shape other than annular.

[0062] The support member 50 is preferably made of a material with excellent heat dissipation properties, such as copper, aluminum, etc. However, the material constituting the support member 50 is not limited to these. By making the annular support member 50 surrounding the substrate 10 a material with excellent heat dissipation properties, heat generated during the light emission operation of the light source 20 can be dissipated to the external space via the substrate 10 and the support member 50.

[0063] The outer surface of the support member 50 may be provided with a plurality of fins to increase the contact area with the external space, thereby further improving the heat dissipation efficiency of the support member 50. In addition, it is preferable that the upper surface of the support member 50 and the lower surface of the spacer 40 are directly bonded to each other.

[0064] When the light emitting device 1 has a support member 50 in contact with the spacer 40, the spacer 40 and the support member 50 can each be in contact with the external space, thereby further improving the heat dissipation efficiency of the spacer 40. In this way, by securing a heat dissipation path other than the outer region of the upper surface 40a of the spacer 40, it is possible to, for example, position the outer edge of the spacer 40 inside the outer edge of the lens 30, thereby making it possible to reduce the size of the light emitting device 1.

[0065] <Cover lens 60> The light emitting device 1 may include a cover lens 60 above the lens 30. The cover lens 60 is disposed above the lens 30 at a distance from the lens 30 by a lens support portion 61 that supports the cover lens 60. As with the lens 30, the material constituting the cover lens 60 may include a light-transmitting resin and optical glass. The cover lens 60 may have a Fresnel lens structure on the lower surface (the lens 30 side), which can reduce the visibility of the internal structure of the light source 20 from the outside. The cover lens 60 may also be a plate-shaped light-transmitting member such as flat glass that does not substantially have a lens function. The lens support portion 61 may be disposed on the spacer 40, for example. In this case, by using a material having excellent heat dissipation properties such as a metal as the material constituting the lens support portion 61, the number of heat dissipation paths via the spacer 40 can be further increased.

[0066] <Heat dissipation effect of spacer 40> Next, an example of the heat dissipation effect in the spacer 40 of the light emitting device 1 will be described with reference to Fig. 3. Fig. 3 is a schematic diagram for explaining an example of the heat dissipation effect in the spacer 40 of the light emitting device 1.

[0067] As described with reference to FIG. 2, the light emitting device 1 includes a spacer 40 bonded to the upper surface 10a of the substrate 10. The spacer 40 includes a metal with excellent heat dissipation properties, such as copper or aluminum. Therefore, after reaching the substrate 10, the heat generated during the light emission operation of the light source 20 is not only dissipated from the lower surface 10b of the substrate 10 to the external space as, for example, a heat flow TF1, but also is transferred from the upper surface 10a of the substrate 10 to the spacer 40 and dissipated to the external space. The heat flows TF2 and TF3 shown in FIG. 3 are examples of heat flows transferred from the upper surface 10a of the substrate 10 to the spacer 40. However, the path of the heat flow transferred from the upper surface 10a of the substrate 10 to the spacer 40 is not limited to the path of the heat flows TF2 and TF3.

[0068] According to the light emitting device 1, by providing the spacer 40, it is possible to increase the number of heat dissipation paths for the heat generated during the light emitting operation of the light source 20. This makes it possible to provide a light emitting device 1 with excellent heat dissipation properties. Accordingly, it becomes possible to increase the current input to the light source 20, and the brightness of the light emitted by the light source 20 can be improved.

[0069] 2, the light emitting device 1 may further include a support member 50 joined to the side surface 10c of the substrate 10. By using a metal material with excellent heat dissipation properties, such as copper or aluminum, for the support member 50, heat generated during the light emission operation of the light source 20 is transferred from the side surface 10c of the substrate 10 to the support member 50 and dissipated to the external space. The heat flows TF4 and TF5 shown in FIG. 3 are examples of heat flows transferred from the side surface 10c of the substrate 10 to the support member 50. However, the path of the heat flow transferred from the side surface 10c of the substrate 10 to the support member 50 is not limited to the path of the heat flows TF4 and TF5.

[0070] By providing the support member 50 joined to the substrate 10, it is possible to further improve the heat dissipation efficiency of the light emitting device 1. Accordingly, the temperature rise of the light source 20 is reduced, and it is possible to increase the current input to the light source 20, thereby further improving the brightness of the light emitted by the light source 20.

[0071] Although the preferred embodiments have been described above in detail, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims. For example, the configuration of the light emitting device 1 is not limited to one including the support member 50. The lens 30 and the spacer 40 may be supported by the substrate 10 or other members.

[0072] Aspects of the present disclosure are, for example, as follows. <Item 1> A substrate, a light source disposed on the substrate; a lens disposed above the light source; a spacer disposed between the substrate and the lens and including a metal; Equipped with When viewed from above, an outer edge of the spacer is located outside an outer edge of the lens. Light emitting device. <Item 2> The light emitting device according to <Item 1>, wherein an upper surface of the substrate and a lower surface of the spacer are directly bonded to each other. <Item 3> The light emitting device according to <Item 1> or <Item 2>, wherein a lower surface of the lens and an upper surface of the spacer are directly bonded to each other. <Item 4> The substrate includes a base and wiring disposed on the base, the wiring includes a connection portion electrically connected to the light source and a heat dissipation portion spaced apart from the connection portion, The light emitting device according to any one of <Item 1> to <Item 3>, wherein a lower surface of the spacer and an upper surface of the heat dissipation portion are directly bonded to each other. <Item 5> The spacer is an annular member surrounding the light source in a top view, The light emitting device according to any one of <Item 1> to <Item 4>, wherein an inner surface of the spacer is provided with a reflective film that reflects light emitted by the light source. <Item 6> The light emitting device according to any one of <Item 1> to <Item 5>, wherein the spacer has fins on an outer surface of the spacer. <Item 7> The spacer has a step portion continuing to an inner surface of the spacer and an upper surface of the spacer, The light emitting device according to any one of <Item 1> to <Item 6>, wherein the lens is supported by the step portion. [Explanation of symbols]

[0073] 1 Light emitting device 10 Substrate 11 Base 12 Top wiring 121a, 121b Connection 122 Heat radiation part 13(13a,13b) Bottom wiring 14(14a,14b) Inner layer wiring 20 light source 21 Light emitting element 211 1st electrode 212 2nd electrode 213 Light-emitting part 22 Wavelength conversion material 30 Lenses 31 Lens section 32 Lens holder 322 Protrusion 40 Spacer 41 Step 45 Reflective film 47 Finn 50 Support member

Claims

1. A substrate; a light source disposed on the substrate; a lens disposed above the light source; a spacer disposed between the substrate and the lens and including a metal; Equipped with When viewed from above, an outer edge of the spacer is located outside an outer edge of the lens. Light emitting device.

2. The light emitting device according to claim 1 , wherein the upper surface of the substrate and the lower surface of the spacer are directly bonded to each other.

3. The light emitting device according to claim 1 , wherein a lower surface of the lens and an upper surface of the spacer are directly bonded to each other.

4. The substrate includes a base and wiring disposed on the base; the wiring includes a connection portion electrically connected to the light source and a heat dissipation portion spaced apart from the connection portion, 3. The light emitting device according to claim 1, wherein a lower surface of the spacer and an upper surface of the heat dissipation portion are directly bonded to each other.

5. the spacer is an annular member surrounding the light source in a top view, The light emitting device according to claim 1 , wherein an inner surface of the spacer is provided with a reflective film that reflects the light emitted by the light source.

6. 3. The light emitting device of claim 1 or 2, wherein the spacer comprises fins on an outer surface of the spacer.

7. the spacer has a step portion continuing to an inner surface of the spacer and an upper surface of the spacer, The light emitting device according to claim 1 , wherein the lens is supported by the step portion.

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