Light-emitting device

Abstract

To reduce deterioration of an adhesive member that bonds optical members.SOLUTION: A light-emitting device includes a base having an upper surface and a recess provided on the upper surface, a light-emitting element disposed in the recess and emitting ultraviolet light, a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin, and an optical member disposed on either an area of the upper surface of the base where the light-transmitting member is not disposed or on the upper surface of the light-transmitting member via a second adhesive member that contains resin, the optical member including a lens portion and a flange portion, and the second adhesive member is disposed outward of the lens portion when viewed from above.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] For example, Patent Document 1 discloses a semi-inorganic package structure for UVC-LED (Light Emitting Diode) that includes a base, a UVC chip disposed on the base, an inorganic lens disposed on the base via an inorganic adhesive, and a photochromic lens (optical component) disposed on the inorganic lens (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Chinese Utility Model No. 218849521 Summary of the Invention [Problem to be solved by the invention]

[0004] An embodiment according to the present disclosure aims to reduce deterioration of an adhesive member that bonds optical members. [Means for solving the problem]

[0005] A light emitting device according to an embodiment of the present disclosure includes a base including an upper surface and a recess provided on the upper surface, a light emitting element disposed in the recess and emitting ultraviolet light, a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin, and an optical member disposed on either an area of ​​the upper surface of the base where the light-transmitting member is not disposed or on the upper surface of the light-transmitting member via a second adhesive member that contains resin, the optical member including a lens portion and a flange portion, wherein the second adhesive member is disposed outward of the lens portion when viewed from above.

[0006] A light emitting device according to an embodiment of the present disclosure includes a base including an upper surface and a recess provided on the upper surface, a light emitting element disposed in the recess and emitting ultraviolet light, a translucent member disposed on the upper surface of the base via a first adhesive member that does not contain resin, and an optical member disposed on the upper surface of the translucent member via a metal adhesive member that contains a metal sintered body and including a lens portion and a flange portion, wherein at least a portion of the metal adhesive member is disposed outside the lens portion when viewed from above. [Effects of the Invention]

[0007] According to the embodiments of the present disclosure, it is possible to reduce deterioration of the adhesive member that bonds the optical member. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic top view showing a light emitting device according to a first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. [Figure 3] 4 is a diagram showing the relationship between the directivity angle and relative radiation intensity of ultraviolet light emitted from the light-emitting element according to the first embodiment. FIG. [Figure 4] FIG. 4 is a schematic top view showing a light emitting device according to a second embodiment. [Figure 5] FIG. 5 is a schematic cross-sectional view taken along line VV in FIG. [Figure 6] FIG. 10 is a schematic top view showing a light emitting device according to a third embodiment. [Figure 7] FIG. 7 is a schematic cross-sectional view taken along line VII-VII in FIG. [Figure 8] FIG. 10 is a schematic top view showing a light emitting device according to a fourth embodiment. [Figure 9] FIG. 9 is a schematic cross-sectional view taken along line IX-IX in FIG. 8. [Figure 10] FIG. 10 is a schematic cross-sectional view showing a light emitting device according to a first modified example. [Figure 11] FIG. 10 is a schematic cross-sectional view showing a light emitting device according to a second modified example. [Figure 12]FIG. 10 is a schematic top view showing a light emitting device according to a third modified example. [Figure 13] FIG. 10 is a schematic cross-sectional view showing a light emitting device according to a fourth modified example. [Figure 14] FIG. 10 is a schematic top view showing the overall configuration of a light emitting device according to a fifth embodiment. [Figure 15] 15 is a schematic cross-sectional view taken along line XV-XV in FIG. 14. [Figure 16] FIG. 11 is a schematic top view of a light-transmitting member in a light-emitting device according to a fifth embodiment. [Figure 17] FIG. 11 is a schematic bottom view of a light-transmitting member in the light-emitting device according to the fifth embodiment. [Figure 18] FIG. 10 is a schematic top view of an optical member in a light emitting device according to a fifth embodiment. [Figure 19] FIG. 11 is a schematic bottom view of an optical member in a light emitting device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Light-emitting devices according to embodiments of the present disclosure will be described in detail with reference to the drawings. However, the embodiments shown below are merely illustrative of light-emitting devices for embodying the technical concepts of the present embodiments, and are not limited thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of components described in the embodiments are not intended to limit the scope of the present disclosure to those specific embodiments, and are merely illustrative examples. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. Furthermore, in the following description, the same names and symbols indicate components that are the same or of the same quality, and detailed description will be omitted as appropriate.

[0010] In the diagrams below, directions may be indicated by the X-axis, Y-axis, and Z-axis. The X-axis, Y-axis, and Z-axis are mutually perpendicular directions. The direction in which the arrow points in the X direction is referred to as the +X direction or +X side, and the direction opposite to the +X direction is referred to as the -X direction or -X side. The direction in which the arrow points in the Y direction is referred to as the +Y direction or +Y side, and the direction opposite to the +Y direction is referred to as the -Y direction or -Y side. The direction in which the arrow points in the Z direction is referred to as the +Z direction or +Z side, and the direction opposite to the +Z direction is referred to as the -Z direction or -Z side.

[0011] In addition, in the following description, terms indicating specific directions or positions (such as "above," "below," and other terms including these terms) may be used. These terms are used merely to make relative directions or positions in the referenced drawings easier to understand. In the following description, "above" refers to the +Z direction side, and "below" refers to the -Z direction side. "Placing" does not only refer to direct contact, but also includes indirect placement, for example, via another member. "Top view" refers to viewing an object from the +Z direction. In addition, an end view showing only the cut surface may be used as a cross-sectional view.

[0012] [First embodiment] <Configuration of the Light-Emitting Device According to the First Embodiment> The configuration of the light emitting device according to the first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic top view showing the light emitting device 100 according to the first embodiment. FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. 1. FIG. 3 is a diagram showing the relationship between the directivity angle θ of the ultraviolet light U emitted from the light emitting element 2 according to the first embodiment and the relative radiant intensity I. In the example shown in FIG. 1, the second adhesive member 5 is hatched to facilitate identification of the components. In the example shown in FIG. 2, arrows indicate part of the ultraviolet light U emitted from the light emitting element 2.

[0013] The light emitting device 100 includes a base 1 including an upper surface 11 and a recess 12 provided on the upper surface 11 side, a light emitting element 2 disposed in the recess 12 and emitting ultraviolet light, and a light-transmitting member 4 disposed on the upper surface 11 of the base 1 via a first adhesive member 3 that does not contain resin. The light emitting device 100 also includes an optical member 6 disposed on the upper surface 41 of the light-transmitting member 4 via a second adhesive member 5 that contains resin, and including a lens portion 61 and a flange portion 62. The second adhesive member 5 is disposed outside the lens portion 61 in a top view.

[0014] In the light emitting device 100, ultraviolet light U is emitted from the light emitting element 2. The ultraviolet light U emitted upward from the light emitting element passes through the light-transmitting member 4 and the optical member 6 and is emitted to the outside. The light emitting device 100 can reduce the ultraviolet light U irradiated onto the second adhesive member 5. This reduces deterioration of the second adhesive member 5. Reducing deterioration of the second adhesive member 5 reduces a decrease in the adhesive strength of the second adhesive member 5 that bonds the light-transmitting member 4 and the optical member 6. Furthermore, reducing deterioration of the second adhesive member 5 reduces discoloration of the second adhesive member 5. If the second adhesive member 5 discolors, the second adhesive member 5 may absorb the ultraviolet light U. In the light emitting device 100, even if the second adhesive member 5 discolors, the second adhesive member 5 is disposed outside the lens portion 61, so that the ultraviolet light U traveling from the light emitting element 2 to the lens portion 61 is less likely to be absorbed by the discolored second adhesive member 5. As a result, the decrease in the light extraction efficiency of the ultraviolet light U emitted to the outside from the lens portion 61 can be reduced.

[0015] In the light-emitting device 100, as shown in FIG. 2 , in a cross-sectional view, the width W1 of the light-transmitting member 4 and the width W2 of the optical member 6 are each wider than the width W3 of the base 1. As a result, when the second adhesive member 5 is disposed on the outer end side of the upper surface 41 of the light-transmitting member 4, a portion of the ultraviolet light U traveling toward the second adhesive member 5 can be blocked by the inner surface 131 that defines the recess in the base 1. This reduces the ultraviolet light U irradiated onto the second adhesive member 5, thereby reducing deterioration of the second adhesive member 5. Note that, in FIG. 2 , the "width of the light-transmitting member 4" refers to the distance in the X direction from the outer end on the -X side to the outer end on the +X side of the lower surface 42 of the light-transmitting member 4. In FIG. 2 , the "width of the optical member 6" refers to the distance in the X direction from the outer end on the -X side to the outer end on the +X side of the lower surface 63 of the optical member 6. In FIG. 2, the "width of base 1" refers to the distance in the X direction from the outer end on the -X side of upper surface 11 of side wall portion 13, which is located on the -X side, of two side wall portions 13 of base 1, to the outer end on the +X side of upper surface 11 of side wall portion 13, which is located on the +X side, of two side wall portions 13 of base 1.

[0016] In the light emitting device 100, in a cross-sectional view, the width W1 of the light-transmitting member 4 is narrower than the width W2 of the optical member 6. The second adhesive member 5 is disposed in an area including the outer end portion on the lower surface of the optical member 6, and is also disposed on part of the side surface of the light-transmitting member 4. This makes it possible to increase the adhesive strength of the second adhesive member 5 that bonds the light-transmitting member 4 and the optical member 6 together.

[0017] The second adhesive member 5 is not limited to being disposed in a region including the outer end of the lower surface of the optical member 6, but may be disposed apart from the outer end of the lower surface of the optical member 6. Furthermore, the second adhesive member 5 is not limited to being disposed on a part of the side surface 43 of the light-transmitting member 4, but may be disposed on the entire side surface 43 of the light-transmitting member 4, or may not be disposed on the side surface of the light-transmitting member 4.

[0018] In the example shown in FIG. 1 , the outer shape of each of the base 1, the light-transmitting member 4, and the optical member 6 is rectangular when viewed from above. Note that a rectangle is a shape that includes four sides and four corners. However, the outer shape of at least one of the base 1, the light-transmitting member 4, and the optical member 6 may be substantially rectangular. The term "substantially rectangular" refers to shapes that include not only a rectangle, but also a rectangle with some of the corners removed, a rectangle with rounded corners, and the like. Furthermore, the outer shape of at least one of the base 1, the light-transmitting member 4, and the optical member 6 when viewed from above is not limited to a rectangle or substantially rectangular, and may be substantially circular, substantially elliptical, substantially polygonal, or the like.

[0019] Each component of the light emitting device 100 will be described in detail below.

[0020] (Base 1) The base 1 is a member for arranging the light-emitting element 2. The base 1 includes a base 17 and a sidewall 13 located on the base 17. The base 1 includes an upper surface 11 and a recess 12 provided on the upper surface 11 side. The upper surface 11 of the base 1 is the upper surface of the sidewall 13. The recess 12 is defined by an inner surface 131 of the sidewall 13 and a bottom surface 14. The bottom surface 14 is the bottom of the recess 12 and corresponds to the upper surface of the base 17. The space within the recess 12 is defined by the inner surface 131 of the sidewall 13, the bottom surface 14, and a lower surface 42 of the light-transmitting member 4. In the example shown in FIG. 1 , the sidewall 13 is arranged in a ring shape so as to surround the light-emitting element 2. Furthermore, the shape of the upper surface 11 of the base when viewed from above is a rectangular ring shape.

[0021] The base 17 and side wall 13 of the substrate 1 are made of an insulating material, such as ceramic. The ceramic is preferably one with high heat resistance and weather resistance. Examples of ceramic that can be used include aluminum nitride, aluminum oxide, and mullite. In the example shown in FIG. 2, the base 17 and side wall 13 are made of the same material as a single body. However, this is not limiting, and the base 17 and side wall 13 may be made of different materials as separate bodies.

[0022] The base 1 includes wiring. The wiring is arranged, for example, on the bottom surface 14 of the recess 12 (i.e., the upper surface of the base 17) and is configured of upper surface wiring electrically connected to the light-emitting element 2, lower surface wiring arranged on the lower surface of the base 17, and relay wiring electrically connecting the upper surface wiring and the lower surface wiring.

[0023] (Light-emitting element 2) The light-emitting element 2 is disposed on the bottom surface 14 of the recess 12. The peak wavelength of the ultraviolet light U emitted by the light-emitting element 2 is, for example, not less than 200 nm and not more than 410 nm. An LED can be used as the light-emitting element 2. In the example shown in FIGS. 1 and 2, the light-emitting device 100 includes one light-emitting element 2. However, the number of light-emitting elements 2 included in the light-emitting device 100 is not limited to one, and may be multiple.

[0024] When viewed from above, the outer shape of the light-emitting element 2 is, for example, rectangular. When the outer shape of the light-emitting element 2 is rectangular, the light-emitting element 2 is preferably arranged so that the bisector of the angle at the vertex of the light-emitting element 2 intersects with the side of the base 1 at a substantially perpendicular angle, as shown in FIG. 1 . This arrangement can reduce absorption of ultraviolet light U emitted from the light-emitting element 2 by the inner surface 131 of the base 1. However, the light-emitting element 2 may also be arranged so that the side of the light-emitting element 2 is substantially parallel to the side of the base 1.

[0025] (First adhesive member 3) The first adhesive member 3 is a member for bonding the base 1 and the translucent member 4. The first adhesive member 3 is disposed on the upper surface 11 of the base 1. The first adhesive member 3 is made of a material that does not contain resin. Therefore, even if the first adhesive member 3 is irradiated with ultraviolet light U emitted from the light-emitting element, the first adhesive member 3 is not easily deteriorated. For example, a solder alloy such as gold-tin or a metal material such as a brazing material can be used for the first adhesive member 3. When the first adhesive member 3 is based on a metal material, for example, a first metal film is provided on the base 1 and a second metal film is provided on the translucent member 4, and the first metal film and the second metal film are bonded together with the first adhesive member 3, thereby bonding the base 1 and the translucent member 4 via the first adhesive member 3. By disposing and bonding the first adhesive member 3 around the entire periphery of the upper surface 11, which has a rectangular ring shape when viewed from above, the space within the recess 12 can be made airtight. This reduces deterioration of the light-emitting element 2.

[0026] (Translucent member 4) The light-transmitting member 4 is a member having light-transmitting properties that transmit at least the ultraviolet light U emitted from the light-emitting element 2. The light-transmitting member 4 transmits 60% or more of the ultraviolet light U emitted from the light-emitting element 2, and preferably transmits 90% or more.

[0027] The light-transmitting member 4 is disposed on the base 1 so as to cover the upper part of the space within the recess 12 in which the light-emitting element 2 is disposed. By covering the upper part of the space within the recess 12 with the light-transmitting member 4, the light-emitting element 2 can be protected from moisture, organic matter, etc. contained in the outside air.

[0028] The material for the light-transmitting member 4 can be, for example, a material whose linear expansion coefficient is small compared to the material for the base 17 and sidewall 13 of the base 1. Even if the base 17, sidewall 13, and light-transmitting member 4 of the base 1 expand due to temperature changes in the light-emitting device 100, it is possible to reduce the stress load corresponding to the difference in linear expansion coefficient between the base 17 and sidewall 13 of the base 1 and the light-transmitting member 4, and the decrease in adhesive strength of the first adhesive member 3 that bonds the sidewall 13 of the base 1 to the light-transmitting member 4. When aluminum nitride is used as the material for the base 17 and sidewall 13 of the base 1, sapphire can be used as the material for the light-transmitting member 4. However, the material for the light-transmitting member 4 is not limited to sapphire, and glass, etc., can be used.

[0029] (Second adhesive member 5) The second adhesive member 5 is a member for adhering the optical member 6. In this embodiment, the second adhesive member 5 is a member for adhering the optical member 6 and the light-transmitting member 4. The second adhesive member 5 is made of a resin material such as silicone resin. Since the second adhesive member 5 contains resin, it may be deteriorated when irradiated with ultraviolet light U from the light-emitting element 2. As described above, the second adhesive member 5 is disposed outside the lens portion 61 in a top view, and therefore, it is possible to reduce the ultraviolet light U irradiated to the second adhesive member 5 and reduce deterioration of the second adhesive member 5.

[0030] 2, the inner end 51 of the second adhesive member 5 is preferably located outside the inner end 31 of the first adhesive member 3. This allows the first adhesive member 3 and the inner surface 131 of the side wall portion 13 to block part of the ultraviolet light U emitted from the light emitting element 2 and traveling in the direction where the second adhesive member 5 is located. As a result, the ultraviolet light U irradiated onto the second adhesive member 5 is reduced, and deterioration of the second adhesive member 5 can be reduced.

[0031] (Optical component 6) The optical member 6 is a member for controlling the light distribution characteristics. The optical member 6 is disposed on the light-transmitting member 4. The optical member 6 transmits the ultraviolet light U emitted from the light-emitting element 2. The optical member 6 can transmit the ultraviolet light U from the light-emitting element 2 and can also converge or diverge the ultraviolet light U before emitting it. The optical member 6 can be configured to include glass materials such as borosilicate glass and quartz glass.

[0032] In the example shown in FIG. 2 , the optical member 6 is a plano-convex lens having a flat lower surface 63 facing the light-transmitting member 4 and a convex surface on the side opposite the lower surface 63 facing the light-transmitting member 4. However, the optical member 6 may also be a plano-concave lens having a concave surface on the upper side opposite the lower surface 63 facing the light-transmitting member 4. The optical member 6 may also be a lens array having a plurality of convex or concave surfaces on the side opposite the lower surface 63 facing the light-transmitting member 4. Furthermore, the optical member 6 may be a Fresnel lens, a diffractive lens, or the like. When the light-emitting device 100 includes a plurality of light-emitting elements 2, the optical member 6 may include a plurality of lens portions 61 corresponding to the plurality of light-emitting elements 2, or may include one lens portion 61 inside which each of the plurality of light-emitting elements 2 is arranged when viewed from above.

[0033] In a top view, the flange 62 is located outside the lens portion 61. The flange 62 is arranged in an annular shape outside the lens portion 61. In the example shown in FIG. 1, the outer ends of the upper and lower surfaces of the flange 62 are rectangular, and the inner end of the upper surface of the flange 62 (i.e., the shape of the outer end 610 of the lens portion) is circular. In the example shown in FIG. 1, the flange 62 includes four corners. The flange 62 is a portion to which the second adhesive member 5 is adhered when the optical member 6 is adhered to the light-transmitting member 4 by the second adhesive member 5. In the example shown in FIG. 1, the second adhesive member 5 is arranged on the outer end side of the lower surface of the flange 62 in a top view, and is continuously arranged around the entire circumference of the annular flange 62. The second adhesive member 5 has a rectangular annular shape in a top view.

[0034] The lens portion 61 has a lens surface and is a portion that realizes a lens function. In the example shown in FIG. 1 , in a top view, a portion 611 of an outer end portion 610 of the lens portion 61 located on the side of an area between adjacent corners of the flange portion 62 overlaps with the upper surface 11 of the base 1. In addition, in a top view, a portion 612 of the outer end portion 610 of the lens portion 61 located on the side of an area of ​​a corner of the flange portion 62 overlaps with the recessed portion 12 of the base 1. That is, in a top view, a portion of the outer end portion 610 of the lens portion 61 overlaps with the upper surface 11, and the remaining portion overlaps with the recessed portion 12. Note that, in a top view, it is not limited to a case where a portion of the outer end portion 610 of the lens portion 61 overlaps with the upper surface 11 and the remaining portion overlaps with the recessed portion 12, and the entire outer end portion 610 of the lens portion 61 may overlap with the upper surface 11. When viewed from above, if a portion of the outer end 610 of the lens portion 61 overlaps the upper surface 11 and the remaining portion overlaps the recess 12, optical characteristics with a narrow light distribution similar to that when the entire outer end 610 of the lens portion 61 overlaps the upper surface 11 can be obtained even if the thickness of the lens portion 61 is made thinner than when the entire outer end 610 of the lens portion 61 overlaps the upper surface 11. This allows the light-emitting device to be made more compact. On the other hand, when the entire outer end 610 of the lens portion 61 overlaps the upper surface 11 in top view, more ultraviolet light U from the light-emitting element 2 can be taken in, and the light extraction efficiency can be improved, compared to when a portion of the outer end 610 of the lens portion 61 overlaps the upper surface 11 and the remaining portion overlaps the recess 12.

[0035] A light-reflecting member can be disposed on the bottom surface 14 of the base 1 in contact with the inner surface 131 of the base 1. The light-reflecting member can be disposed so as to surround the light-emitting element 2. The light-reflecting member is composed of an inorganic material including, for example, boron nitride or alkali metal silicate. It can further include titanium oxide or zirconium oxide. The light-reflecting member can have a sloped region in which the height from the bottom surface 14 decreases from the inner surface 131 toward the light-emitting element 2. The sloped region is disposed continuously on the inner surface 131 and bottom surface 14 of the base 1. By having the sloped region in the light-reflecting member, ultraviolet light U emitted from the light-emitting element 2 and traveling to the light-reflecting member can be reflected upward. As a result, the light extraction efficiency of the light-emitting device 100 can be improved.

[0036] In FIG. 3, graph 301, shown by a solid line, represents the relationship between the directivity angle θ in the X direction and the relative radiant intensity I of the ultraviolet light U emitted from the light-emitting device 100. Graph 302, shown by a dashed line, represents the relationship between the directivity angle θ in the Y direction and the relative radiant intensity I of the ultraviolet light U emitted from the light-emitting device 100. The directivity angle θ, as shown in FIG. 2, refers to the angle θ that represents the spread of the light emitted from the light-emitting element 2 with respect to the optical axis L. The directivity angle θ represents the angle inclined in the +X direction with respect to the optical axis L as +θ°, and the angle inclined in the −X direction with respect to the optical axis L as −θ°. In the example shown in FIG. 3, in both graphs 301 and 302, the relative radiant intensity is high when the directivity angle θ is approximately ±30°. Therefore, it is preferable that the second adhesive member 5, which is disposed between the optical member 6 and the light-transmitting member 4, be disposed outside a position, in a top view, through which the ultraviolet light U emitted from the light-emitting element 2 with a directivity angle θ of approximately ±30° passes. 2 has a directivity angle θ of ±40°, for example. With this arrangement, it is possible to reduce irradiation of the ultraviolet light U having a high relative radiant intensity, out of the ultraviolet light U emitted from the light-emitting element 2, onto the second adhesive member 5, thereby reducing deterioration of the second adhesive member 5.

[0037] <Method of Manufacturing the Light-Emitting Device 100> The manufacturing method of the light emitting device 100 includes, for example, a step (S10) of arranging the light emitting element 2 on the base 1, a step (S11) of arranging the light-transmitting member 4 on the upper surface 11 of the base 1 via a first adhesive member 3, a step (S12) of arranging the second adhesive member 5 on the upper surface 41 of the light-transmitting member 4 and / or the lower surface 63 of the optical member 6, and a step (S13) of arranging the optical member 6 on the upper surface 41 of the light-transmitting member 4 via the second adhesive member 5. The order of S11 to S13 may be S11, S12, S13, or S12, S13, S11.

[0038] [Second embodiment] <Configuration of the Light-Emitting Device According to the Second Embodiment> The configuration of the light emitting device according to the second embodiment will be described with reference to Figures 4 and 5. Note that the same names and symbols as those in the embodiments of the present disclosure already described indicate the same or similar components or configurations, and detailed descriptions will be omitted as appropriate. This also applies to the embodiments and modifications described below.

[0039] Fig. 4 is a schematic top view showing a light emitting device 100a according to a second embodiment. Fig. 5 is a schematic cross-sectional view taken along line VV in Fig. 4. In the example shown in Fig. 4, the second adhesive member 5 is hatched to make it easier to distinguish between the members. In addition, in the example shown in Fig. 5, arrows indicate a portion of the ultraviolet light U emitted from the light emitting element 2.

[0040] In the light emitting device 100a according to the second embodiment, the upper surface 11 of the base 1 has, in a top view, an outer upper surface 15 and an inner upper surface 16 that is located more inward than the outer upper surface 15. The inner upper surface 16 is located lower than the outer upper surface 15. The light-transmitting member 4 is disposed on the inner upper surface 16 via a first adhesive member 3. The optical member 6 is disposed on the outer upper surface 15 via a second adhesive member 5. The light emitting device 100a according to the second embodiment differs mainly from the light emitting device 100 according to the first embodiment in the above points.

[0041] As shown in FIG. 5, in the light emitting device 100a, the second adhesive member 5 is disposed on the outer upper surface 15, so that the ultraviolet light U irradiated onto the second adhesive member 5 can be reduced, and deterioration of the second adhesive member 5 can be reduced.

[0042] 5, in the light-emitting device 100a, the side surface 43 of the light-transmitting member 4 is preferably spaced apart from a side surface 151 (hereinafter, sometimes referred to as a "first side surface 151") that connects the outer upper surface 15 and the inner upper surface 16 of the base 1. For example, if the base 17 and the side wall 13 of the base 1 are made of aluminum nitride and the light-transmitting member 4 is made of sapphire, the light-transmitting member 4 is more likely to expand than the base 17 and the side wall 13 of the base 1 because sapphire has a larger linear expansion coefficient than aluminum nitride. Therefore, even if the light-transmitting member 4 expands due to a temperature change in the light-emitting device 100a, the risk of the first side surface 151 of the base 1 and the side surface 43 of the light-transmitting member 4 coming into contact with each other can be reduced. As a result, stress from the first side surface 151 of the base 1 is prevented from being generated on the side surface 43 of the translucent member 4, thereby reducing the possibility of the translucent member 4 cracking and / or peeling off from the base 1.

[0043] 5, in the light emitting device 100a, the inner end 51 of the second adhesive member 5 is preferably located outside the inner end 152 of the outer upper surface 15 of the base 1. This allows the first side surface 151 to block a portion of the ultraviolet light U emitted from the light emitting element 2 and traveling in the direction where the second adhesive member 5 is located. As a result, the ultraviolet light U irradiated onto the second adhesive member 5 is reduced, and deterioration of the second adhesive member 5 can be reduced. Note that the inner end 51 of the second adhesive member 5 does not necessarily have to be located outside the inner end 152 of the outer upper surface 15 of the base 1, and the inner end 51 of the second adhesive member 5 may also coincide with the inner end 152 of the outer upper surface 15 of the base 1.

[0044] In the light-emitting device 100a, the light-transmitting member 4 and the optical member 6 are in contact with each other. This eliminates any gap between the light-transmitting member 4 and the optical member 6, reducing total reflection that occurs at the boundary between the light-transmitting member 4 and the gas (e.g., air) present in the gap. Since the amount of ultraviolet light U that is totally reflected is reduced, more ultraviolet light U passes through the light-transmitting member 4 and enters the optical member 6, thereby increasing the light extraction efficiency of the light-emitting device 100a. However, the light-transmitting member 4 and the optical member 6 may be spaced apart. When the light-transmitting member 4 and the flange 62 are spaced apart, a gap is formed between the light-transmitting member 4 and the optical member 6. This reduces the risk of the light-transmitting member 4 and the optical member 6 coming into contact with each other even if the light-transmitting member 4 and the optical member 6 expand due to a temperature change in the light-emitting device 100a. Reducing the risk of contact between the light-transmitting member 4 and the optical member 6 reduces at least one of the stress from the light-transmitting member 4 to the optical member 6 and the stress from the optical member 6 to the light-transmitting member. The same applies to light-emitting devices 100b, 100c, and 100g described below.

[0045] In the light emitting device 100a, the lens portion 61 is disposed inward from the outer upper surface 15 in top view. This makes it possible to reduce the amount of ultraviolet light U traveling from the light emitting element 2 to the lens portion 61 passing through the second adhesive member 5. The same applies to the light emitting devices 100b to 100g described below.

[0046] 5, the width of the optical member 6 and the width of the light-transmitting member 4 are narrower than the width of the base 1. The width of the optical member 6 does not necessarily have to be narrower than the width of the base 1, and may be the same as the width of the base 1. The same applies to light-emitting devices 100b and 100c described below.

[0047] <Method of Manufacturing Light-Emitting Device 100a> A manufacturing method of the light emitting device 100a includes, for example, a step (S10) of arranging a light emitting element 2 on a base 1, a step (S21) of arranging a light-transmitting member 4 on the inner upper surface 16 of the base 1 via a first adhesive member 3, a step (S22) of arranging a second adhesive member 5 on the outer upper surface 15 of the base 1 and / or the lower surface 63 of the optical member 6, and a step (S23) of arranging the optical member 6 on the outer upper surface 15 of the base 1 via the second adhesive member 5.

[0048] [Third embodiment] <Configuration of the Light-Emitting Device According to the Third Embodiment> The configuration of a light emitting device according to a third embodiment will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is a schematic top view showing a light emitting device 100b according to the third embodiment. Fig. 7 is a schematic cross-sectional view taken along line VII-VII in Fig. 6. In the example shown in Fig. 6, the second adhesive member 5 is hatched to facilitate identification of the components. In addition, in the example shown in Fig. 7, arrows indicate part of the ultraviolet light U emitted from the light emitting element 2.

[0049] In the light emitting device 100b according to the third embodiment, the upper surface 11 of the base 1 has, in a top view, an outer upper surface 15 and an inner upper surface 16 that is located more inward than the outer upper surface 15. The inner upper surface 16 is located higher than the outer upper surface 15. The light-transmitting member 4 is disposed on the inner upper surface 16 via a first adhesive member 3. The optical member 6 is disposed on the outer upper surface 15 via a second adhesive member 5. The light emitting device 100b according to the third embodiment differs from the light emitting device 100 according to the first embodiment mainly in the above points.

[0050] 7, the optical member 6 includes leg portions 64 below the flange portion 62 and connected to the flange portion 62. The optical member 6 has lower surfaces 641 of the leg portions 64 disposed on the outer upper surface 15 via the second adhesive member 5. The leg portions 64 may be disposed continuously around the entire circumference of the annular flange portion 62 in a top view, or may be disposed intermittently. When the leg portions 64 are disposed intermittently in a top view, the leg portions 64 may be disposed at each of the four corners of the flange portion 62, for example.

[0051] In the light emitting device 100b, the second adhesive member 5 is disposed on the outer upper surface 15, and the inner upper surface 16 is positioned higher than the outer upper surface 15. The ultraviolet light U from the light emitting element 2 is blocked by the second side surface 161 connecting the inner upper surface 16 and the bottom surface 14 of the base 1, and does not reach the second adhesive member 5. As a result, in the light emitting device 100b, the ultraviolet light U irradiated onto the second adhesive member 5 can be further reduced compared to the light emitting devices 100 and 100a, and deterioration of the second adhesive member 5 can be further reduced.

[0052] In the light-emitting device 100b, the side surface of the light-transmitting member 4 is spaced apart from the side surface of the leg portion 64 of the optical member 6. This reduces the risk of the leg portion 64 of the optical member 6 and the side surface 43 of the light-transmitting member 4 coming into contact with each other even if the light-transmitting member 4 expands due to a temperature change in the light-emitting device 100b. As a result, no stress is generated between the base 1 and the light-transmitting member 4, reducing the possibility of at least one of cracking of the light-transmitting member 4, cracking of the optical member 6, peeling of the first adhesive member 3, and peeling of the second adhesive member 5. Furthermore, because there is a gap between the side surface of the light-transmitting member 4 and the side surface of the leg portion 64 of the optical member 6, a portion of the ultraviolet light U traveling from the side surface of the light-transmitting member 4 to the optical member 6 is totally reflected at the boundary between the side surface of the light-transmitting member 4 and the gas (e.g., air) present in the gap. This increases the amount of light that reaches the lens portion 61 of the optical member 6, thereby increasing the light extraction efficiency of the light-emitting device 100b. However, the present invention is not limited to this, and the side surface of the light-transmitting member 4 may be in contact with the side surface of the leg portion 64 of the optical member 6.

[0053] In the light emitting device 100b, the side surfaces of the leg portions 64 of the optical member 6 are in contact with the first side surface 151 of the base 1. This facilitates alignment of the optical member 6. However, the side surfaces of the leg portions 64 of the optical member 6 may be spaced apart from the first side surface 151 of the base 1.

[0054] In the light emitting device 100b, the second adhesive member 5 is disposed on the outer upper surface 15 of the base 1, and further contacts the first side surface 151. This can improve the adhesion between the second adhesive member 5 and the base 1.

[0055] <Method of Manufacturing Light-Emitting Device 100b> A manufacturing method of the light emitting device 100b includes, for example, a step (S10) of arranging a light emitting element 2 on a base 1, a step (S31) of arranging a light-transmitting member 4 on the inner upper surface 16 of the base 1 via a first adhesive member 3, a step (S32) of arranging a second adhesive member 5 on the outer upper surface 15 of the base 1 and / or the lower surface 63 of the optical member 6, and a step (S33) of arranging the optical member 6 on the outer upper surface 15 of the base 1 via the second adhesive member 5.

[0056] [Fourth embodiment] <Configuration of the Light-Emitting Device According to the Fourth Embodiment> The configuration of the light emitting device according to the fourth embodiment will be described with reference to Fig. 8 and Fig. 9. Fig. 8 is a schematic top view showing a light emitting device 100c according to the fourth embodiment. Fig. 9 is a schematic cross-sectional view taken along line IX-IX in Fig. 8. In the example shown in Fig. 8, the second adhesive member 5 is hatched to make it easier to distinguish between components. In the example shown in Fig. 9, arrows indicate part of the ultraviolet light U emitted from the light emitting element 2.

[0057] In the light-emitting device 100c according to the fourth embodiment, the upper surface 11 of the base 1 has, in a top view, an outer upper surface 15 and an inner upper surface 16 located more inward than the outer upper surface 15. The inner upper surface 16 is flush with the outer upper surface 15. The light-transmitting member 4 is disposed on the inner upper surface 16 via a first adhesive member 3. The optical member 6 is disposed on the outer upper surface 15 via a second adhesive member 5. The light-emitting device 100c according to the fourth embodiment differs from the light-emitting device 100 according to the first embodiment mainly in the above points. The outer upper surface 15 corresponds to the region of the upper surface 11 of the base 1 where the second adhesive member 5 is disposed, and the inner upper surface 16 corresponds to the region where the second adhesive member 5 is not disposed. Here, the "height" refers to the distance in the +Z direction from the bottom surface 14 of the recess 12 of the base 1.

[0058] 9, the optical member 6 includes, below the flange 62, leg portions 64 that connect to the flange 62. The optical member 6 is arranged such that a lower surface 641 of the leg portions 64 is on the outer upper surface 15 via the second adhesive member 5.

[0059] In the light emitting device 100c, by disposing the second adhesive member 5 on the outer upper surface 15, the second adhesive member 5 can be disposed in a region close to the outer end on the upper surface 11 when viewed from above. This makes it possible to reduce the ultraviolet light U irradiated onto the second adhesive member 5 in the light emitting device 100c, and reduce deterioration of the second adhesive member 5.

[0060] In the light emitting device 100c, the second adhesive member 5 is in contact with the first adhesive member 3. This increases the adhesive strength with which the light-transmitting member 4 is bonded to the base 1 via the first adhesive member 3. However, the second adhesive member 5 may be spaced apart from the first adhesive member 3.

[0061] <Method of manufacturing the light emitting device 100c> A manufacturing method of the light emitting device 100c includes, for example, a step (S10) of arranging a light emitting element 2 on a base 1, a step (S41) of arranging a light-transmitting member 4 on the inner upper surface 16 of the base 1 via a first adhesive member 3, a step (S42) of arranging a second adhesive member 5 on the outer upper surface 15 of the base 1, and a step (S43) of arranging an optical member 6 on the outer upper surface 15 of the base 1 and / or the lower surface 63 of the optical member 6 via the second adhesive member 5.

[0062] [Variations] (First Modification) The configuration of a light emitting device according to a first modification will be described with reference to Fig. 10. Fig. 10 is a schematic cross-sectional view showing a light emitting device 100d according to the first modification. Fig. 10 shows a cross section of the light emitting device 100d corresponding to line II-II in Fig. 1.

[0063] The light emitting device 100d differs from the light emitting device 100 according to the first embodiment in that it has anti-reflection films 7 arranged on the lens portion 61, the upper surface 621 of the flange portion 62, and the side surface 622 of the flange portion 62, respectively.

[0064] In the light emitting device 100d, by having the reflection reduction film 7, stray light resulting from ultraviolet light emitted from the light emitting element 2 and reflected by the lens portion 61, the upper surface 621 and the side surface 622 of the flange portion 62 can be reduced.

[0065] (Second Modification) The configuration of a light emitting device according to a second modification will be described with reference to Fig. 11. Fig. 11 is a schematic cross-sectional view showing a light emitting device 100e according to the second modification. Fig. 11 shows a cross section of the light emitting device 100e corresponding to line II-II in Fig. 1.

[0066] The light emitting device 100e differs from the light emitting device 100 according to the first embodiment in that the second adhesive member 5 is disposed on a side surface 622 of the flange 62. In the light emitting device 100e, the second adhesive member 5 is disposed between the optical member 6 and the light-transmitting member 4, on the side surface 622 of the flange 62, and on the side surface 43 of the light-transmitting member 4. This increases the adhesive strength of the second adhesive member 5 that bonds the optical member 6 and the light-transmitting member 4. Note that the second adhesive member 5 may be disposed between the optical member 6 and the light-transmitting member 4 and on the side surface 622 of the flange 62 instead of on the side surface 43 of the light-transmitting member.

[0067] (Third Modification) The configuration of a light emitting device according to a third modified example will be described with reference to Fig. 12. Fig. 12 is a schematic top view showing a light emitting device 100f according to a third modified example. In the example shown in Fig. 12, the second adhesive member 5 is hatched to make it easier to distinguish the members.

[0068] The light emitting device 100f differs from the light emitting device 100 according to the first embodiment in that the second adhesive members 5 are arranged discretely around the entire circumference of the annular flange 62 of the optical member 6 in a top view. In the light emitting device 100f, the second adhesive members 5 are arranged between the light-transmissive member 4 and the optical member 6 at each of the four corners of the flange 62.

[0069] The second adhesive members 5 are discretely arranged around the entire circumference of the annular flange 62 of the optical member 6, which reduces the effect of a decrease in the light extraction efficiency of the light emitting device due to discoloration of the second adhesive members 5 compared to when the second adhesive members 5 are continuously arranged around the entire circumference of the annular flange 62 as shown in Fig. 1. On the other hand, the second adhesive members 5 are continuously arranged around the entire circumference of the annular flange 62 as shown in Fig. 1, which increases the adhesive strength of the second adhesive members 5 that bond the optical member 6 and the light-transmitting member 4 together compared to when the second adhesive members 5 are discretely arranged.

[0070] (Fourth Modification) The configuration of a light emitting device according to the fourth modification will be described with reference to Fig. 13. Fig. 13 is a schematic cross-sectional view showing a light emitting device 100g according to the fourth modification.

[0071] The light emitting device 100g of the fourth modified example differs from the light emitting device 100 of the first embodiment in that the upper surface 41 of the translucent member 4 and the lower surface 42 of the optical member 6 are in contact with each other, and the second adhesive member 5 is disposed between the side surface 43 of the translucent member 4 and the lower surface 42 of the optical member 6.

[0072] [Fifth embodiment] A light emitting device according to a fifth embodiment will be described with reference to Fig. 14 to Fig. 19. Fig. 14 is a schematic top view showing the overall configuration of a light emitting device 100h according to the fifth embodiment. Fig. 15 is a schematic cross-sectional view taken along line XV-XV in Fig. 14. Fig. 16 is a schematic top view of the light-transmitting member 4 in the light emitting device 100h. Fig. 17 is a schematic bottom view of the light-transmitting member 4 in the light emitting device 100h. Fig. 18 is a schematic top view of the optical member 6 in the light emitting device 100h. Fig. 19 is a schematic bottom view of the optical member 6 in the light emitting device 100h.

[0073] The light emitting device 100h of this embodiment differs from the light emitting device 100 of the first embodiment in that the optical element 6 is arranged on the upper surface 41 of the light-transmitting element 4 via a metal adhesive element 5h containing a metal sintered body instead of the second adhesive element.

[0074] 14, the base 1, the light-emitting element 2, the light-transmitting member 4, and the optical member 6 each have a rectangular shape when viewed from above. However, the shapes of the base 1, the light-emitting element 2, the light-transmitting member 4, and the optical member 6 when viewed from above may be other shapes such as a circle, an ellipse, or a polygon, and may be different from each other.

[0075] 15 , a metal film 8 in contact with the first adhesive member 3 is disposed on each of the base 1 and the light-transmitting member 4. The metal film 8 includes a first metal film 81 and a second metal film 82. The first metal film 81 is disposed on the upper surface 11 of the base 1 and is bonded to the first adhesive member 3. The second metal film 82 is disposed on the lower surface 42 of the light-transmitting member 4 and is bonded to the first adhesive member 3.

[0076] Furthermore, a metal film 9 in contact with the metal adhesive member 5h is disposed on each of the optical member 6 and the light-transmitting member 4. The metal film 9 includes a third metal film 91 and a fourth metal film 92. The third metal film 91 is disposed on the upper surface 41 of the light-transmitting member 4 and is bonded to the metal adhesive member 5h. The fourth metal film 92 is disposed on the lower surface 63 of the optical member 6 and is bonded to the metal adhesive member 5h. Note that the metal film 9 is not limited to being disposed on each of the optical member 6 and the light-transmitting member 4, and may be disposed on at least one of the optical member 6 and the light-transmitting member 4.

[0077] (Metal adhesive material 5h) When a metal sintered body is used as the metal adhesive member 5h, a metal paste containing metal particles is heated at a temperature lower than the melting point of the metal and baked to form a sintered body, thereby bonding the members together. The metal paste is disposed on a third metal film 91 disposed on the upper surface of the light-transmitting member 4. The metal paste is disposed on the third metal film 91 by, for example, coating. The metal paste contains at least one type of particle selected from the group consisting of silver particles, copper particles, and gold particles. From the viewpoint of the light reflectivity of the metal adhesive member 5h to the ultraviolet light U from the light-emitting element 2, it is preferable to use silver particles as the raw material for the metal sintered body.

[0078] The melting point of the metal adhesive member 5h is lower than the melting point of the first adhesive member 3. For example, in the manufacturing process of the light-emitting device 100h, the light-transmitting member 4 is adhered to the base 1 using the first adhesive member 3, and then the optical member 6 is adhered to the light-transmitting member 4 using the metal adhesive member 5h. If the melting point of the metal adhesive member 5h is the same as or higher than the melting point of the first adhesive member 3, the first adhesive member 3 may melt when the metal adhesive member 5h is melted to adhere the optical member 6. Melting of the first adhesive member 3 may cause the light-transmitting member 4 to peel off from the base 1. In this embodiment, since the melting point of the metal adhesive member 5h is lower than the melting point of the first adhesive member 3, the first adhesive member 3 does not melt even when the metal adhesive member 5h is melted to position the optical member 6 in the manufacturing process of the light-emitting device 100h. This reduces the possibility that the light-transmitting member 4 will peel off from the base 1 due to melting of the first adhesive member 3.

[0079] The Young's modulus of the metal adhesive member 5h is preferably lower than that of the first adhesive member 3. For example, if the optical member 6 is made of glass, there is a possibility that the optical member 6 will crack when the optical member 6 is bonded onto the light-transmitting member 4 via the metal adhesive member 5h. By making the Young's modulus of the metal adhesive member 5h lower than that of the first adhesive member 3, the distortion of the optical member 6 during bonding can be absorbed by the metal adhesive member, which has low rigidity. As a result, the possibility of the optical member 6 cracking is reduced.

[0080] (Position of metal adhesive member 5h) 14, the entire metal adhesive member 5h is disposed outside the lens portion 61 of the optical member 6 in a top view. The metal adhesive members 5h are disposed intermittently in the circumferential direction on the outer periphery of the optical member 6. Furthermore, the metal adhesive members 5h are disposed at each of the four corners 65 of the optical member 6. Note that the corners refer to areas including the intersections where two sides intersect and the vicinity of the intersections.

[0081] By disposing the entire metal adhesive member 5h outside the lens portion 61 in top view, it is possible to reduce the ultraviolet light U irradiated onto the metal adhesive member 5h and reduce deterioration of the metal adhesive member 5h. However, when the metal adhesive member 5h includes a sintered metal body, the metal adhesive member 5h is less susceptible to photodegradation due to irradiation with the ultraviolet light U than when the metal adhesive member 5h is made of resin. Therefore, in the light emitting device 100h, when the metal adhesive member 5h includes a sintered metal body, a part of the metal adhesive member 5h can be positioned inside the outer end portion 610 of the lens portion 61 in top view.

[0082] The metal adhesive member 5h may or may not protrude from the fourth metal film 92 in top view. In the example shown in Fig. 14, the metal adhesive member 5h protrudes from the fourth metal film 92 in top view. When the metal adhesive member 5h protrudes from the fourth metal film 92 in top view, the metal adhesive member 5h covers the side surface of the fourth metal film 92. This increases the contact area between the metal adhesive member 5h and the fourth metal film 92, and increases the adhesive strength between the optical member 6 and the light-transmitting member 4.

[0083] The light emitting device 100h may or may not have a second adhesive member 5 disposed outside the metal adhesive member 5h between the light-transmissive member 4 and the optical member 6 to bond the light-transmissive member 4 and the optical member 6. When the second adhesive member 5 is disposed outside the metal adhesive member 5h, the metal adhesive member 5h improves light resistance to ultraviolet light U from the light emitting element, and the second adhesive member 5 improves sulfuration resistance to sulfides present in the outside air. When the light emitting device 100h has the metal adhesive member 5h and the second adhesive member 5, for example, the metal adhesive member 5h and the second adhesive member 5 can be obtained by disposing a metal paste and an uncured resin on the upper surface of the light-transmissive member and heating the metal paste and the uncured resin simultaneously.

[0084] (Material of Metal Film 9) The metal film 9 may be made of gold or the like.

[0085] (Position of metal film 9) 14, the metal film 9 is located outside the lens portion 61 in top view. The metal film 9 is disposed intermittently in the circumferential direction on the outer periphery of each of the optical member 6 and the light-transmitting member 4. Specifically, the metal film 9 is disposed at each of four corners 65 of the optical member 6 and the light-transmitting member 4. The corners of the optical member 6 and the light-transmitting member 4 overlap in top view, and the corners 65 represent the corners of the optical member 6 and the light-transmitting member 4.

[0086] The fourth metal film 92 of the metal film 9 may overlap the entire third metal film 91 in top view, or may overlap a part of the third metal film 91. The metal film 9 may overlap the entire metal film 8 in top view, or may overlap a part of the metal film 8.

[0087] In top view, the metal film 9 is located outside the lens portion 61. This makes it difficult for the ultraviolet light U traveling from the light-emitting element 2 to hit the metal film 9, thereby reducing the decrease in the light extraction efficiency of the ultraviolet light U emitted from the lens portion 61 to the outside.

[0088] When the metal film 9 is disposed intermittently in the circumferential direction on the outer peripheries of the optical member 6 and the light-transmitting member 4, the area of ​​the region where the metal film 9 is disposed is smaller on each of the optical member 6 and the light-transmitting member 4 compared to when the metal film 9 is disposed continuously in the circumferential direction on the outer peripheries of the optical member 6 and the light-transmitting member 4. This reduces the amount of ultraviolet light U emitted from the light-emitting element 2 that is incident on the metal film 9, thereby reducing light absorption by the metal film 9 and improving the light extraction efficiency of the light-emitting device 100h. Note that the metal film 9 is not limited to being disposed intermittently in the circumferential direction on the outer peripheries of the optical member 6 and the light-transmitting member 4, and may be disposed intermittently in the circumferential direction on the outer periphery of either the optical member 6 or the light-transmitting member 4.

[0089] (Shape of metal film 9) In the example shown in Figure 16, when viewed from above, the third metal films 91 arranged at each of the four corners on the upper surface 41 of the light-transmitting member 4 all have a shape that is point-symmetric with respect to the center 4C of the light-transmitting member 4.

[0090] In the example shown in FIG. 19, the fourth metal films 92 disposed at each of the four corners of the lower surface 63 of the optical member 6 include a fourth metal film 92-1, a fourth metal film 92-2, a fourth metal film 92-3, and a fourth metal film 92-4.

[0091] In top view, the fourth metal film 92-2 and the fourth metal film 92-3 have shapes that are point-symmetric with respect to the center 6C of the optical member 6. Furthermore, the fourth metal film 92-2 and the fourth metal film 92-4 have shapes that are symmetric with respect to a line that is parallel to the X direction and passes through the center of the optical member 6. In top view, the fourth metal film 92-1 has a shape that is not point-symmetric with the fourth metal film 92-4.

[0092] In top view, the fourth metal film 92-1 includes a curved inner edge and an outer edge having a right-angled portion 920 where two sides intersect at a right angle. In contrast, the fourth metal film 92-2, the fourth metal film 92-3, and the fourth metal film 92-4 include a curved inner edge 922 and a curved outer edge 921.

[0093] In the light emitting device 100h, the fourth metal film 92-1 can be used as an identification mark. For example, in the light emitting device 100h, the fourth metal film 92-1 can be used as a cathode mark. However, the fourth metal films 92 disposed at the four corners can all have shapes that are point-symmetric with respect to the center 6C of the optical member 6 when viewed from above.

[0094] 16, the curved surfaces of the outer edge 911 and the inner edge 912 of each of the four third metal films 91 have the same curvature when viewed from above. The curvature of this curved surface can be the same as the curvature of the curved surface of the outer end of the lens portion 61, for example. In addition, in the example shown in FIG. 19, the curved surfaces of the inner edge 922 of the fourth metal film 92-1 and the outer edge 921 and the inner edge 922 of each of the fourth metal films 92-2, 92-3, and 92-4 have the same curvature when viewed from above. The curvature of this curved surface can be the same as the curvature of the curved surface of the outer end of the lens portion 61, for example.

[0095] In the example shown in FIG. 16 , a third metal film 91 is disposed at each of the four corners 65 on the upper surface 41 of the light-transmitting member 4, and further, a metal film 10 is disposed between each of the corners. The metal film 10 is made of, for example, the same material as the third metal film 91. The metal film 10 can be used as a mark for aligning the optical member 6 when placing the optical member 6 on the light-transmitting member 4. Using the metal film 10 as an alignment mark improves the alignment accuracy of the optical member 6. The metal film 10 may or may not be in contact with the metal adhesive member 5h.

[0096] The preferred embodiments have been described in detail above. However, 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. The above-described embodiments and modifications can be implemented in combination with each other.

[0097] All ordinal numbers, quantitative numbers, and other figures used in the description of the embodiments are provided as examples to specifically explain the technology of the present disclosure, and the present disclosure is not limited to the illustrated figures. Furthermore, the connection relationships between components are provided as examples to specifically explain the technology of the present disclosure, and do not limit the connection relationships that realize the functions of the present disclosure.

[0098] The light-emitting device of the present disclosure can reduce deterioration of the adhesive member disposed between the optical member and the light-transmitting member, and is therefore suitable for use in applications such as printing and exposure in which an object is irradiated with ultraviolet light to harden the object, although the light-emitting device of the present disclosure is not limited to these applications.

[0099] Aspects of the present disclosure are, for example, as follows. <Item 1> A light emitting device including: a base including an upper surface and a recess provided on the upper surface; a light emitting element disposed in the recess and emitting ultraviolet light; a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin; and an optical member disposed on either a region of the upper surface of the base where the light-transmitting member is not disposed or on the upper surface of the light-transmitting member via a second adhesive member that contains resin, the optical member including a lens portion and a flange portion, wherein the second adhesive member is disposed outward of the lens portion in a top view. <Item 2> The light emitting device according to <Item 1>, wherein, in a cross-sectional view, the width of the light-transmitting member and the width of the optical member are each wider than the width of the base. <Item 3> The light emitting device according to <Item 1> or <Item 2>, wherein the width of the translucent member is narrower than the width of the optical member in a cross-sectional view. <Item 4> The light emitting device according to any one of <Item 1> to <Item 3>, wherein the upper surface of the base has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, the inner upper surface being located lower than the outer upper surface, the translucent member being disposed on the inner upper surface via the first adhesive member, and the optical member being disposed on the outer upper surface via the second adhesive member. <Item 5> The light emitting device according to any one of <Item 1> to <Item 3>, wherein the upper surface of the base has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, the inner upper surface being located higher than the outer upper surface, the translucent member being disposed on the inner upper surface via the first adhesive member, and the optical member being disposed on the outer upper surface via the second adhesive member. <Item 6> The light emitting device according to any one of <Item 1> to <Item 3>, wherein the upper surface of the base has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, the inner upper surface being flush with the outer upper surface, the translucent member being disposed on the inner upper surface via the first adhesive member, and the optical member being disposed on the outer upper surface via the second adhesive member. <Item 7> The light emitting device according to <Item 4> or <Item 5>, wherein the light-transmitting member and the optical member are in contact with each other. <Item 8> The light emitting device according to <Item 4> or <Item 5>, wherein the light-transmitting member and the optical member are spaced apart. <Item 9> The light emitting device according to <Item 4>, wherein the side surface of the light-transmitting member is spaced apart from the side surface connecting the outer upper surface and the inner upper surface of the base. <Item 10> The light emitting device according to <Item 4> or <Item 5>, wherein the lens portion is disposed more inward than the outer upper surface in a top view. <Item 11> The light emitting device according to <Item 4>, wherein, in top view, an inner end of the second adhesive member is spaced apart from an inner end of the outer upper surface of the base. <Item 12> The light emitting device according to any one of <Item 1> to <Item 11>, further comprising anti-reflection films disposed on the lens portion, the upper surface of the flange portion, and the side surfaces of the flange portion. <Item 13> The light emitting device according to any one of <Item 1> to <Item 12>, wherein the second adhesive member is disposed between the optical member and the translucent member and on a side surface of the flange portion. <Item 14> A light emitting device comprising: a base including an upper surface and a recess provided on the upper surface; a light emitting element disposed in the recess and emitting ultraviolet light; a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin; and an optical member disposed on the upper surface of the light-transmitting member via a metal adhesive member that contains a sintered metal, the optical member including a lens portion and a flange portion, wherein at least a portion of the metal adhesive member is disposed outside the lens portion in a top view. <Item 15> The light emitting device according to <Item 14>, wherein the entire metal adhesive member is disposed outside the lens portion in a top view. <Item 16> The light-emitting device according to <Item 14> or <Item 15>, wherein a metal film in contact with the metal adhesive member is disposed on at least one of the optical member and the translucent member, and the metal film is positioned outside the lens portion in a top view. <Item 17> The light emitting device according to <Item 16>, wherein the metal film is intermittently disposed on the entire periphery of at least one of the optical member and the light-transmitting member. <Item 18> The light-emitting device according to <Item 17>, wherein the optical member and the translucent member are rectangular in top view, and the metal film is disposed at at least one corner of the optical member and the translucent member. [Explanation of symbols]

[0100] 1 Base 11 Top side 12 recess 13 Side wall 131 Inner surface 14 Bottom 15 Outer top surface 151 First aspect 152 Inner end 16 Inside top surface 161 Second aspect 162 Inner end 17 Base 2 Light-emitting element 3. First adhesive member 31 Inner end 4 Translucent material 4C center 41 Top side 42 Bottom surface 43 Side 5 Second adhesive member 5h Metal adhesive material 51 Inner end 6 Optical Components 6C center 61 Lens section 62 Tsuba 621 Top surface 622 Side 63 Bottom surface 64 Legs 641 Bottom surface 7. Anti-reflection coating 8, 9, 10 Metallic film 81 First metal film 82 Second metal film 91 Third metal film 92, 92-1, 92-2, 92-3, 92-4 Fourth metal film 920 Right angle 911, 921 outer edge 912, 922 Common-law marriage 301, 302 graphs 610 Outer edge 100, 100a, 100b, 100c, 100d, 100e, 100f, 100g, 100h Light-emitting device U ultraviolet light W1, W2, W3 width θ Directional angle

Claims

1. a base including an upper surface and a recess provided on the upper surface; a light emitting element disposed in the recess and emitting ultraviolet light; a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin; an optical member including a lens portion and a flange portion, the optical member being disposed via a second adhesive member containing a resin on either a region of the upper surface of the base where the light-transmitting member is not disposed or on the upper surface of the light-transmitting member; The light emitting device, wherein the second adhesive member is disposed outside the lens portion in a top view.

2. The light emitting device according to claim 1 , wherein, in a cross-sectional view, the width of the translucent member and the width of the optical member are each wider than the width of the base.

3. The light emitting device according to claim 1 , wherein the width of the translucent member is narrower than the width of the optical member in a cross-sectional view.

4. the upper surface of the base body has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, the inner upper surface is located lower than the outer upper surface, the translucent member is disposed on the inner upper surface via the first adhesive member, The light emitting device according to claim 1 , wherein the optical member is disposed on the outer upper surface via the second adhesive member.

5. the upper surface of the base body has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, the inner upper surface is located higher than the outer upper surface, the translucent member is disposed on the inner upper surface via the first adhesive member, The light emitting device according to claim 1 , wherein the optical member is disposed on the outer upper surface via the second adhesive member.

6. the upper surface of the base body has, in a top view, an outer upper surface and an inner upper surface located more inward than the outer upper surface, The inner upper surface is flush with the outer upper surface, the translucent member is disposed on the inner upper surface via the first adhesive member, The light emitting device according to claim 1 , wherein the optical member is disposed on the outer upper surface via the second adhesive member.

7. The light emitting device according to claim 4 , wherein the light-transmitting member and the optical member are in contact with each other.

8. The light emitting device according to claim 4 , wherein the light-transmitting member and the optical member are spaced apart from each other.

9. The light emitting device according to claim 4 , wherein the side surface of the light-transmitting member is spaced apart from a side surface of the base body that connects the outer upper surface and the inner upper surface.

10. The light emitting device according to claim 4 , wherein the lens portion is disposed more inward than the outer upper surface in a top view.

11. The light emitting device according to claim 4 , wherein an inner edge of the second adhesive member is spaced apart from an inner edge of the outer upper surface of the base when viewed from above.

12. The light emitting device according to claim 1 , further comprising a reflection reducing film disposed on each of the lens portion, the upper surface of the flange portion, and the side surface of the flange portion.

13. The light emitting device according to claim 1 , wherein the second adhesive member is disposed between the optical member and the light-transmitting member and on a side surface of the flange portion.

14. a base including an upper surface and a recess provided on the upper surface; a light emitting element disposed in the recess and emitting ultraviolet light; a light-transmitting member disposed on the upper surface of the base via a first adhesive member that does not contain resin; an optical member including a lens portion and a flange portion, the optical member being disposed on the upper surface of the light-transmitting member via a metal adhesive member including a sintered metal body; At least a portion of the metal adhesive member is disposed outside the lens portion in a top view.

15. The light emitting device according to claim 14 , wherein the entire metal adhesive member is disposed outside the lens portion in a top view.

16. a metal film in contact with the metal adhesive member is disposed on at least one of the optical member and the light-transmitting member; The light emitting device according to claim 14 , wherein the metal film is located outside the lens portion in a top view.

17. The light emitting device according to claim 16 , wherein the metal film is intermittently disposed around the entire periphery of at least one of the optical member and the light-transmitting member.

18. the optical member and the light-transmitting member are rectangular in top view, The light emitting device according to claim 17 , wherein the metal film is disposed at a corner of at least one of the optical member and the light-transmitting member.

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