Light-emitting device

The light-emitting device addresses misalignment issues in collimating lens arrays by using a substrate with uniform lens curvature and vertex distances, ensuring consistent light intensity and reducing interference, thus enhancing collimation and miniaturization.

JP7842366B2Active Publication Date: 2026-04-08NICHIA CORP
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Patent Information

Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2025-04-15
Publication Date
2026-04-08

AI Technical Summary

Technical Problem

Conventional light source devices with collimating lens arrays experience significant deviations in light intensity distribution due to misalignment caused by slight rotations of the lens elements, leading to inconsistent light emission.

Method used

The light-emitting device features a substrate with a recess and a lens array where lens portions have uniform curvature and vertex distances, ensuring precise alignment and minimizing misalignment, along with a sealing member to maintain hermeticity and reduce interference.

Benefits of technology

The solution provides a stable light-emitting device with consistent light intensity distribution and reduced misalignment, enabling efficient collimation and miniaturization while suppressing thermal and optical interference.

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Patent Text Reader

Abstract

To provide a light emitting device in which, even when a lens array is mounted while being slightly rotated from a predetermined direction, a significant deviation hardly occurs in a positional relationship between a light source and a lens section and, consequently, an intensity distribution of light emitted from the lens array hardly changes.SOLUTION: A light emitting device includes a substrate, a lens array having a plurality of lens sections in a matrix, and a plurality of semiconductor laser elements disposed on the substrate. The semiconductor laser elements emit respective laser beams. Each laser beam has a beam shape with a greater width in a column direction than in a row direction on a light incident surface of each of the plurality of lens sections. The plurality of lens sections have an inter-vertex distance in the row direction which is smaller than both a maximum outer diameter of each of the lens sections, and an inter-vertex distance in the column direction. A curvature of the lens sections in the row direction is the same as that of the lens sections in the column direction.SELECTED DRAWING: Figure 1A
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Description

Technical Field

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

Background Art

[0002] There is known a light source device that collimates light emitted from a plurality of light sources by a collimating lens array (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above conventional light source device, each lens element constituting the collimating lens array has a plurality of curvatures according to the cross-sectional shape of the laser light incident on each lens element. Therefore, even if the collimating lens array is mounted with a slight rotation from a predetermined orientation, a large deviation may occur in the positional relationship between the light source and the lens element, and there is a risk that the intensity distribution of the light emitted from the collimating lens array may change.

Means for Solving the Problems

[0005] The light-emitting device disclosed in the embodiment comprises a substrate having a recess, a plurality of semiconductor laser elements disposed in the recess of the substrate, a sealing member joined to the substrate and sealing the space in which the plurality of semiconductor laser elements are disposed, and a lens array having a plurality of lens portions arranged in a connected direction and joined to the sealing member, wherein the distance between the vertices of adjacent lens portions in the first direction is smaller than the maximum outer diameter of the lens portion, the plurality of lens portions and the plurality of semiconductor laser elements correspond one-to-one, light emitted from each semiconductor laser element passes through the vertex of the corresponding lens portion, and the lens portions located at both ends of the plurality of lens portions arranged in a connected direction have a greater width in the first direction than the lens portions located elsewhere. [Brief explanation of the drawing]

[0006] [Figure 1A] This is a schematic plan view of the light-emitting device according to Embodiment 1. [Figure 1B] This is a cross-sectional view AA in Figure 1A. [Figure 1C] This is a cross-sectional view of BB in Figure 1A. [Figure 1D] This is a cross-sectional view of CC in Figure 1A. [Figure 2A] This is a schematic plan view of the substrate. [Figure 2B] This is a cross-sectional view of DD in Figure 2A. [Figure 2C] This is a cross-sectional view of EE in Figure 2A. [Figure 3A] This is a schematic plan view of the lens array. [Figure 3B] This is a cross-sectional view of FF in Figure 3A. [Figure 3C] This is a cross-sectional view of GG in Figure 3A. [Figure 3D] This is a cross-sectional view of HH in Figure 3A. [Figure 4A] This is a schematic plan view of a semiconductor laser element arranged on a substrate. [Figure 4B] This is a cross-sectional view II in Figure 4A. [Figure 4C] This is a cross-sectional view of JJ in Figure 4A. [Figure 4D] It is a view showing an enlarged portion surrounded by a broken line in FIG. 4C. [Figure 5A] It is a schematic plan view of a sealing member. [Figure 5B] It is a cross-sectional view taken along the line K-K in FIG. 5A. [Figure 5C] It is a cross-sectional view taken along the line L-L in FIG. 5A. [Figure 6A] It is a schematic plan view of a light-emitting device according to Embodiment 2. [Figure 6B] It is a cross-sectional view taken along the line M-M in FIG. 6A. [Figure 6C] It is a cross-sectional view taken along the line N-N in FIG. 6A. [Figure 6D] It is a cross-sectional view taken along the line O-O in FIG. 6A. [Figure 7] It is a schematic plan view of a light-emitting device according to Embodiment 3. [Figure 8] It is a schematic plan view of a light-emitting device according to Embodiment 4.

Mode for Carrying Out the Invention

[0007] [Light-Emitting Device According to Embodiment 1] FIG. 1A is a schematic plan view of a light-emitting device according to Embodiment 1. Further, FIG. 1B is a cross-sectional view taken along the line A-A in FIG. 1A, FIG. 1C is a cross-sectional view taken along the line B-B in FIG. 1A, and FIG. 1D is a cross-sectional view taken along the line C-C in FIG. 1A. In FIG. 1A, for ease of understanding, the semiconductor laser element 30 and the like disposed below the leftmost upper lens portion are shown transparently. As shown in FIGS. 1A to 1D, the light-emitting device 1 according to Embodiment 1 is a light-emitting device including a substrate 10, a lens array 20 having a plurality of lens portions 22 arranged in a matrix, and a plurality of semiconductor laser elements 30 disposed on the substrate 10. The plurality of semiconductor laser elements 30 each emit laser light, and each laser light has a beam shape that is wider in the column direction than in the row direction at each light incident surface LA of the plurality of lens portions 22. The plurality of lens portions 22 have an inter-vertex distance PX in the row direction that is smaller than either the maximum outer diameter E of each individual lens portion 22 or the inter-vertex distance PY in the column direction, and have the same curvature in the row direction and the column direction.

[0008] The following will be described in order.

[0009] (Substrate 10) FIG. 2A is a schematic plan view of the substrate. Further, FIG. 2B is a cross-sectional view taken along the line D-D in FIG. 2A, and FIG. 2C is a cross-sectional view taken along the line E-E in FIG. 2A. As shown in FIGS. 2A to 2C, the substrate 10 has, for example, a base portion 12, a side wall 14 protruding from the base portion 12, and a recess 10a formed by the base portion 12 and the side wall 14. The base portion 12 has a convex portion 12a, and the convex portion 12a is formed inside the recess 10a. By using the base portion 12 having such a convex portion 12a, it is possible to suppress the warping of the base portion 12 that may occur due to the substrate 10 having the recess 10a (this warping is likely to occur particularly when the base portion 12 and the side wall 14 are made of different materials), so that it becomes easy to mount a semiconductor laser element 30 or the like on the base portion 12. Further, by arranging members such as the semiconductor laser element 30 on the convex portion 12a, these members can be brought closer to the lens array 20, so that it is also possible to suppress the spread of the laser light on the light incident surface LA of the lens array 20 (lens portion 22). Note that the shapes and thicknesses of the substrate 10, the base portion 12, and the side wall 14 are not particularly limited. For example, in addition to the member having the recess 10a, the substrate 10 can also use, for example, a flat member (e.g., a member consisting only of the base portion 12 without the side wall 14).

[0010] For the substrate 10 (base portion 12, side wall 14), a metal material such as iron, an iron alloy, or copper, a ceramic material such as AlN, SiC, or SiN, or a material combining these materials can be used.

[0011] The base body 10 is provided with wiring 90 (e.g., leads) for electrically connecting the light-emitting device 1 to the outside. The wiring 90 may be provided anywhere on the outer circumference of the light-emitting device 1, but it is preferable that it be provided on the top or side surface of the base body 10. In other words, it is preferable that the wiring 90 is not provided on the bottom surface of the base body 10. In this way, the entire bottom surface of the base body 10 can be used as a mounting surface, and even when multiple semiconductor laser elements 30 that serve as heat sources are arranged on a single base body 10 as in this disclosure, a light-emitting device with good heat dissipation can be provided. Note that if wiring 90 is provided on the side wall 14 of the base body 10, the height of the side wall 14 must be above a certain level, so the semiconductor laser elements 30 etc. arranged on the base 12 will be positioned further away from the lens array 20 than if wiring 90 is not provided on the side wall 14. However, by using the base 12 having the aforementioned protrusion 12a, it becomes possible to position the semiconductor laser elements 30, mirrors 50 etc. closer to the lens array 20 (lens section 22) even in such cases.

[0012] (Lens array 20) Figure 3A is a schematic plan view of the lens array. Figure 3B is a cross-sectional view of FF in Figure 3A, Figure 3C is a cross-sectional view of GG in Figure 3A, and Figure 3D is a cross-sectional view of HH in Figure 3A. As shown in Figures 3A to 3D, the lens array 20 has a plurality of lens sections 22 and connecting sections 24. Each lens section 22 has an incident light surface LA and an outgoing light surface LB, and each laser beam incident on the incident light surface LA of each lens section 22 is refracted and emitted from the outgoing light surface LB of each lens section 22. The connecting sections 24 connect adjacent lens sections 22 in the column direction (Y direction in Figure 1). The lens array 20 can also be composed of only lens sections 22. In this case, for example, the lens sections 22 are directly connected to each other without the connecting sections 24. The lens array 20 (lens sections 22 and connecting sections 24) can be formed using translucent materials such as glass or synthetic quartz.

[0013] (Multiple lens sections 22) Multiple lens units 22 are arranged in a matrix of m rows and n columns (m≧2, n≧1). Each of the multiple lens units 22 has a vertex distance PX in the row direction (X direction in Figure 1) that is smaller than either the maximum outer diameter E of the individual lens unit 22 or the vertex distance PY in the column direction (Y direction in Figure 1). In this way, each lens unit 22 is formed in a continuous row direction (X direction in Figure 1), thus reducing wasted space where laser light is not emitted in the row direction (X direction in Figure 1) and enabling miniaturization of the lens array 20 (and consequently the light-emitting device 1). Note that "vertex distance in the column direction" refers to the distance between the vertices of adjacent lens units in the column direction. Similarly, "vertex distance in the row direction" refers to the distance between the vertices of adjacent lens units in the row direction. Furthermore, "vertex" refers to the center of the lens unit in a plan view, and "maximum outer diameter" refers to the longest diameter of the lens unit in a plan view.

[0014] The distance between vertices PY in the column direction (Y direction in Figure 1) can preferably be 1 mm or more and 12 mm or less, more preferably 3 mm or more and 9 mm or less. The distance between vertices PX in the row direction (X direction in Figure 1) can preferably be 0.5 mm or more and 9 mm or less, more preferably 2 mm or more and 6 mm or less. By setting the distances between vertices PX and PY to be above these lower limits, interference between laser beams from adjacent semiconductor laser elements 30 can be suppressed. Furthermore, by setting the distances between vertices PX and PY to be below these upper limits, a smaller light-emitting device can be provided.

[0015] The maximum outer diameter E of each lens portion 22 can be preferably 1 to 2 times, more preferably 1.25 to 1.75 times, the distance between vertices PX. By setting the maximum outer diameter E above these lower limits, interference between laser beams from adjacent semiconductor laser elements 30 can be suppressed. Furthermore, by setting the maximum outer diameter E below these upper limits, a smaller light-emitting device can be provided.

[0016] Each lens portion 22 has the same curvature in the row direction (X direction in Figure 1) and the column direction (Y direction in Figure 1). That is, each lens portion 22 has a curve with curvature RX in the cross-section in the row direction (X direction in Figure 1) passing through the vertex of the lens portion 22, and a curve with curvature RY equal to curvature RX (curvature RX = curvature RY) in the cross-section in the column direction (Y direction in Figure 1) passing through the vertex of the lens portion 22. In this way, even if the lens array 20 is mounted rotated slightly from a predetermined orientation, a large deviation in the positional relationship between the light source (semiconductor laser element 30; mirror 50 if a mirror 50 is provided; the same applies hereinafter) and the lens portion 22 is unlikely to occur. It is preferable that each lens portion 22 has the same curvature not only in the row direction (X direction in Figure 1) and the column direction (Y direction in Figure 1), but also in all directions passing through the vertex of each lens portion 22, that is, that each lens portion 22 has a curve with the same curvature in all cross-sections passing through the vertex of each lens portion 22. This approach further reduces the likelihood of significant misalignment between the light source and the lens unit 22.

[0017] The multiple lens portions 22 are not particularly limited, but preferably have a shape that can collimate the laser light incident from the semiconductor laser element 30. For example, it is preferable that each of the multiple lens portions 22 consists of at least a portion of an aspherical curved surface (e.g., the light incident surface LA is a plane and the light output surface LB is an aspherical curved surface). In this way, the laser light from the semiconductor laser element 30 can be collimated without changing the light intensity distribution.

[0018] Preferably, each of the multiple lens portions 22 has at least a portion of its periphery that is arc-shaped in plan view. This allows for more aspherical curved surfaces to be provided on the lens portion 22 compared to cases where they have other plan view shapes, thus enabling efficient emission of laser light from the semiconductor laser element 30 through the lens portion 22.

[0019] The lens array 20 can be fixed to the base body 10 (or to the sealing member 80 if one is provided between the base body 10 and the lens array 20) by known methods. For example, when the lens array 20 is directly fixed to the base body 10, the lens array 20 and the base body 10 can be fixed by methods such as adhesive fixing, laser welding, or resistance welding. When fixing by laser welding or resistance welding, at least the welded portion of the lens array 20 is made of a metal material. Also, when a sealing member 80 is provided between the base body 10 and the lens array 20, the lens array 20 and the sealing member 80 can be bonded and fixed together using an adhesive such as a UV-curable adhesive.

[0020] To create a sealed space around the semiconductor laser element 30, it is preferable to fix a lid-like member to the base 10 by welding. However, welding is prone to misalignment. Therefore, if the lens array is directly fixed to the base by welding and the lens array directly covers the base, the lens array may become misaligned, potentially preventing light from the semiconductor laser element from being incident on the lens portion in a predetermined manner (e.g., predetermined divergence angle, predetermined positional relationship). In this embodiment, a sealing member 80, which is a separate component from the lens array 20, is provided, and the base 10 is covered by the sealing member 80. In this way, the sealing member 80 is fixed to the base 10 by welding, while the lens array 20 can be fixed to the sealing member 80 with a UV-curable adhesive. This allows the space around the semiconductor laser element 30 to be sealed by the sealing member 80 while suppressing misalignment of the lens array 20. It is possible.

[0021] (Multiple semiconductor laser elements 30) Figure 4A is a schematic plan view of a semiconductor laser element arranged on a substrate. Figure 4B is a cross-sectional view of section II in Figure 4A, Figure 4C is a cross-sectional view of section JJ in Figure 4A, and Figure 4D is an enlarged view of the area enclosed by the dashed line in Figure 4C. As shown in Figures 4A to 4D, multiple semiconductor laser elements 30 are arranged on a substrate 10. Specifically, the multiple semiconductor laser elements 30 are arranged in the row direction (X direction in Figure 4) and the column direction (Y direction in Figure 4). The semiconductor laser elements 30 can be placed directly on the bottom surface of the recess 10a of the substrate 10 (or on the protrusion 12a if a base 12 with a protrusion 12a is used), or they can be placed via a mounting body 40 or the like. If they are placed via a mounting body 40, the heat generated by the multiple semiconductor laser elements 30 can be efficiently dissipated via the mounting body 40.

[0022] Each of the multiple semiconductor laser elements 30 emits laser light, and each laser beam is incident on the respective light incident surface LA of the lens section 22, either directly or via a mirror 50 or the like. Each laser beam has a beam shape at each light incident surface LA of the multiple lens sections 22 in which the width is wider in the column direction (Y direction in Figure 1) than in the row direction (X direction in Figure 1) (beam width WY in the column direction > beam width WX in the row direction). The multiple semiconductor laser elements 30 can be semiconductor laser elements made of nitride semiconductors, etc.

[0023] Multiple semiconductor laser elements 30 can be electrically connected to each other by wires 60 or the like. Gold, silver, copper, aluminum, etc., can be used as the wires 60. The connection method is not particularly limited, but for example, multiple semiconductor laser elements 30 arranged in the row direction (X direction in Figure 1) can be connected in series using wires 60.

[0024] In Figure 4A, multiple semiconductor laser elements 30 are arranged in a straight line in each row, and a relay member 70 is provided between adjacent semiconductor laser elements 30. The adjacent semiconductor laser elements 30 are electrically connected by wires 60 via the relay member 70. This allows the length of each wire 60 to be relatively short, thereby suppressing an increase in electrical resistance. In addition, the distance between adjacent semiconductor laser elements 30 in each row can be increased, thereby reducing thermal interference between the semiconductor laser elements 30. As the relay member 70, a metal material such as iron, iron alloy, or copper, or an insulating material such as AlN, SiC, or SiN with electrical wiring formed on its upper surface can be used. No semiconductor laser elements 30 are placed on the relay member 70.

[0025] The upper surface of the relay member 70 is preferably located at substantially the same height as the upper surface of the mounting body 40 or the upper surface of the semiconductor laser element 30. This makes it easier to mount the wire 60. When the semiconductor laser element 30 is provided on the mounting body 40, the upper surface of the relay member 70 is preferably located at substantially the same height as the upper surface of the mounting body 40. This makes it possible to reduce the thickness of the relay member 70 in the height direction compared to when it is at substantially the same height as the upper surface of the semiconductor laser element 30, thereby reducing material costs.

[0026] The semiconductor laser elements 30 are arranged in an m-row and n-column (m≧2, n≧1) configuration, corresponding to each lens section. Preferably, the number of semiconductor laser elements 30 in the row direction is greater than the number of semiconductor laser elements 30 in the column direction. Furthermore, the semiconductor laser elements 30 are arranged such that the distribution of light from the multiple semiconductor laser elements 30 (light as the light-emitting device 1) forms a square. This makes it easier to uniformize the distribution of light emission intensity when the light-emitting device 1 is used as part of a projector.

[0027] (Mirror 50) As shown in Figures 4A to 4D, the light-emitting device 1 may be equipped with a mirror 50 on the substrate 10 that reflects the light emitted from the semiconductor laser element 30 toward the lens section 22. The mirror 50 is positioned so that the emission surface of the semiconductor laser element 30 (the surface from which the laser light is emitted; the same applies hereinafter) and the mirror 50 face each other. This makes it possible to increase the distance (hereinafter referred to as "optical path length") from the light emitted from the light emission surface of the semiconductor laser element 30 to the emission surface of the lens section 22. Therefore, the light density at the light emission surface of the lens array 20 can be reduced, making it easier to suppress dust collection at the lens section 22. In addition, by increasing the optical path length, it is possible to reduce the change in the intensity distribution of the light emitted from the lens section 22 compared to the case where the optical path length is short (for example, when light is directly irradiated from the semiconductor laser element 30 to the lens section 22 without arranging the mirror 50). This is because, by increasing the optical path length, even if the light from the semiconductor laser element 30 is incident from a direction other than perpendicular to the light incident surface of the lens portion 22 due to a misalignment of the semiconductor laser element 30, the tilt of the light after passing through the lens portion 22 can be reduced.

[0028] The number and shape of the mirrors 50 are not particularly limited. For example, multiple long mirrors may be arranged in a row in the row direction (X direction in Figure 1), or multiple mirrors 50 may be arranged in a matrix of m rows and n columns (m≧2, n≧1) corresponding to multiple lens sections 22. When arranged in a matrix, one mirror 50 is provided for each of the multiple lens sections 22, so even if there is a misalignment in the positional relationship between one semiconductor laser element 30 and one mirror 50, it will not affect the positional relationship between other semiconductor laser elements 30 and other mirrors 50. Therefore, the impact of mounting misalignment of one mirror 50 can be minimized.

[0029] The mirror 50 can be made of glass, synthetic quartz, sapphire, aluminum, or the like. The mirror 50 has a reflective surface that reflects the light emitted from the semiconductor laser element 30 (laser light emitted from the semiconductor laser element 30; the same applies hereinafter). The reflective surface is provided with a reflective film, such as a dielectric multilayer film. If the mirror 50 is not used and the light emitted from each of the multiple semiconductor laser elements 30 is directly incident on the lens array 20, for example, instead of using the mirror 50, the multiple semiconductor laser elements 30 can be arranged on the substrate 10 in a matrix of m rows and n columns (m≧2, n≧1).

[0030] The mirror 50 is not particularly limited, but it is preferably located directly below the apex of the lens portion 22. In particular, it is preferable that the reflective portion of the mirror 50 is located directly below the apex of the lens portion 22. In this way, the mirror 50 can reflect the light emitted from the semiconductor laser element 30 toward the apex of the lens portion 22, so that the intensity distribution of the light emitted from the lens array 20 (lens portion 22) does not change easily. The reflective portion referred to here is the part of the reflective surface provided on the mirror 50 that reflects the light emitted from the semiconductor laser element 30.

[0031] As shown in Figures 1A to 1D (for example, see the semiconductor laser element 30 and mirror 50 transparently shown in the lens portion 22 located in the upper left of Figure 1A), it is preferable that the semiconductor laser element 30 and mirror 50 are positioned inward from the periphery of the lens portion 22 in a plan view. In this way, the semiconductor laser element 30 is positioned close to the mirror 50, which suppresses the increase in the area of ​​light emitted from the lens portion 22.

[0032] (Sealing member 80) As shown in Figures 1A to 1D, the light-emitting device 1 may include a sealing member 80 between the substrate 10 and the lens array 20. By providing the sealing member 80, the effect of hermetically sealed packaging can be enhanced compared to the case where only the lens array 20 is provided. In particular, when a nitride semiconductor is used as the semiconductor laser element 30, organic matter and the like tend to accumulate on the emission surface of the semiconductor laser element 30, so the effect of hermetically sealed packaging by the sealing member 80 becomes even more pronounced.

[0033] Figure 5A is a schematic plan view of the sealing member. Figure 5B is a cross-sectional view of KK in Figure 5A, and Figure 5C is a cross-sectional view of LL in Figure 5A. In Figure 5A, the window portion 82a is shown transparently with a dashed line for ease of understanding. As shown in Figures 5A to 5C, the sealing member 80 has a main body portion 82 having a plurality of window portions 82a and a light-transmitting member 84. The main body portion 82 can be made of glass, metal, ceramic, or a combination of these materials, and metal is preferably used. This makes it easier to fix the base body 10 and the sealing member 80 by welding or the like, thus facilitating hermetically sealed sealing. In addition, the light-transmitting member 84 can be made of a material that transmits at least the emitted light from the semiconductor laser element 30. The shapes of the main body portion 82 and the light-transmitting member 84 are not particularly limited. For example, in this embodiment, the main body portion 82 has a recess 82b on the lens array 20 side, but if a flat plate-shaped member is used as the base body 10, the recess 82b may be on the base body 10 side.

[0034] The main body portion 82 may have one window portion 82a for two or more semiconductor laser elements 30, but it is preferable that each of the multiple semiconductor laser elements 30 has one window portion 82a. This increases the bonding area between the main body portion 82 excluding the window portion 82a and the translucent member 84, thereby suppressing cracking of the translucent member 84 due to stress when the base body 10 and the main body portion 82 are joined by resistance welding or the like for hermetically sealing.

[0035] As described above, according to the light-emitting device 1 of Embodiment 1, the multiple lens sections 22 have the same curvature in the row direction (X direction in Figure 1) and the column direction (Y direction in Figure 1). Therefore, even if the lens array 20 is mounted slightly rotated from a predetermined orientation, a large shift in the positional relationship between the light source and the lens sections 22 is unlikely to occur, and a light-emitting device can be provided in which the intensity distribution of light emitted from the lens array 20 does not change easily.

[0036] [Light-emitting device 2 according to Embodiment 2] Figure 6A is a schematic plan view of the light-emitting device according to Embodiment 2, Figure 6B is a cross-sectional view of MM in Figure 6A, Figure 6C is a cross-sectional view of NN in Figure 6A, and Figure 6D is a cross-sectional view of OO in Figure 6A. In Figure 6A, for ease of understanding, the semiconductor laser element 30 and other components located below the upper left lens section are shown transparently. As shown in Figures 6A to 6D, the light-emitting device 2 according to Embodiment 2 differs from the light-emitting device 1 according to Embodiment 1 in that multiple lens arrays 20A, 20B, 20C, and 20D are arranged in the column direction (Y direction in Figure 1), and each of the multiple lens arrays 20A, 20B, 20C, and 20D has multiple lens sections 22 in the row direction (X direction in Figure 1). Embodiment 2, like Embodiment 1, can provide a light-emitting device in which even if the lens array 20 is mounted slightly rotated from a predetermined orientation, a large displacement in the positional relationship between the light source and the lens section 22 is less likely to occur, and the intensity distribution of the light emitted from the lens array 20 is less likely to change.

[0037] [Light-emitting device 3 according to Embodiment 3] Figure 7 shows a schematic plan view of the light-emitting device 3 according to Embodiment 3. In Figure 7, the outer edge of the recess 82b is shown by a dashed line. Also in Figure 7, the area in which the lens array 20 is fixed to the sealing member 80 by adhesive is hatched. As shown in Figure 7, in the light-emitting device 3, the lens array 20 comprises a lens portion 22 and a connecting portion 24 that connects the lens portions 22 to each other, and is fixed to the sealing member 80 by adhesive at the connecting portion 24. The sealing member 80 has a recess 82b that is recessed toward the area on the substrate 10 on which a plurality of semiconductor laser elements 30 are placed. In a plan view, the lens array 20 has a through hole F inside the recess 82b and is fixed to the sealing member 80 by adhesive outside the recess 82b.

[0038] If the space between the lens array and the sealing member is a sealed space, when the lens array is fixed with an adhesive containing organic matter (e.g., a UV-curable adhesive), the gas vaporized from the adhesive will remain in the space between the lens array and the sealing member. In this case, the organic matter contained in the vaporized gas may react with laser light and accumulate on the translucent member or lens array. In contrast, if a through hole F is provided in the connection part 24, the space between the lens array 20 and the sealing member 80 becomes an open space, allowing the gas vaporized from the adhesive to escape from the space and making it easier to suppress the accumulation (dust collection) of organic matter. An open space refers to a space that is open.

[0039] It is preferable to provide multiple through-holes F. Furthermore, it is preferable that the multiple through-holes F are provided symmetrically with respect to the center line of the lens array 20. This makes it easier to form an airflow in the space between the lens array 20 and the sealing member 80 (for example, if two through-holes are provided symmetrically, an airflow is easily formed in which air flows into the space from one through-hole and out of the space from the other through-hole), thereby further allowing vaporized gas from the adhesive to escape from the space and suppressing the accumulation of organic matter (dust collection) in the space. It is also possible to suppress the occurrence of condensation in the space between the lens array 20 and the sealing member 80. Adhesives containing organic matter, such as UV-curable adhesives, are materials that easily absorb moisture, so when the lens array 20 is fixed with a UV-curable adhesive, moisture absorbed by the adhesive from the atmosphere tends to remain in the space between the sealing member 80 and the lens array 20, and depending on the usage conditions, condensation may occur in the space. Therefore, the above configuration, which forms an airflow within the space, is particularly preferable when fixing the lens array 20 to the sealing member 80 with an adhesive containing organic matter, such as a UV-curable adhesive.

[0040] [Light-emitting device 4 according to Embodiment 4] Figure 8 shows a schematic plan view of the light-emitting device 4 according to Embodiment 4. In Figure 8, the outer edge of the recess 82b is shown with solid and dashed lines. Also in Figure 8, the area where the lens array 20 is fixed to the sealing member 80 with adhesive is hatched. As shown in Figure 8, in the light-emitting device 4, the sealing member 80 has a recess 82b that is recessed toward the area on the substrate 10 where the plurality of semiconductor laser elements 30 are placed. In a plan view, the lens array 20 is positioned such that a part of the outer edge of the lens array 20 is located inside the recess 82b (see opening G in Figure 8), and is fixed to the sealing member 80 with adhesive outside the recess 82b. In the light-emitting device 4 as well, the space between the lens array 20 and the sealing member 80 is an open space, making it easier to suppress the accumulation of organic matter (dust collection) and the occurrence of condensation.

[0041] The number and arrangement of the openings G are not limited to those shown in Figure 8, as long as a portion of the outer edge of the lens array 20 is positioned inside the recess 82b. However, it is preferable that the openings G are provided at two or more locations (not limited to the four corners) on the outer edge of the lens array 20 in a plan view. In this case, it is preferable that these openings G are positioned point-symmetrically with respect to the center of the lens array 20. This makes it easier to form an airflow in the space between the lens array 20 and the sealing member 80, similar to the case where multiple through holes F are provided symmetrically with respect to the center line of the lens array 20. Therefore, the accumulation of organic matter (dust collection) and the occurrence of condensation can be suppressed even further.

[0042] Embodiments 3 and 4 have been described above, but the through-holes F and openings G are examples of specific configurations that make the space between the lens array 20 and the sealing member 80 an open space. The space between the lens array 20 and the sealing member 80 only needs to be open so that gas generated in the space can escape to the outside, and there are no particular limitations on how such an open space (i.e., an open space) is specifically configured.

[0043] Although embodiments have been described above, these descriptions do not limit the configurations described in the claims in any way. [Explanation of Symbols]

[0044] 1, 2, 3, 4 Light-emitting devices 10 Base 10a recess 12 Base 12a Convex part 14 Side wall 20, 20A, 20B, 20C, 20D lens array 22 Lens section 24 Connection part 30 Semiconductor laser elements 40 Mounting body 50 Mirror 60 wires 70 Intermediate Member 80 Sealing member 82 Main body 82a Window section 82b recess 84 Translucent material 90 Wiring PX: Distance between vertices in the row direction PY column distance between vertices WX beam width in the row direction WY beam width in the column direction LA light incident surface LB light exit surface E Maximum outer diameter F through hole G opening X row direction Y column direction

Claims

1. A base having a recess, A plurality of semiconductor laser elements are arranged in the recess of the substrate, A sealing member that is bonded to the substrate and seals the space in which the plurality of semiconductor laser elements are arranged, A lens array having a plurality of lens portions connected and arranged in a first direction, and joined to the sealing member, The plurality of lens portions are such that the distance between the vertices of adjacent lens portions in the first direction is smaller than the maximum outer diameter of the lens portion. The plurality of lens portions and the plurality of semiconductor laser elements correspond one-to-one, and the light emitted from each semiconductor laser element passes through the corresponding vertex of the lens portion. A light-emitting device in which, among a plurality of lens sections arranged in a line connected in the first direction, the lens sections located at both ends have a greater width in the first direction than the lens sections located at other ends.

2. The light-emitting device according to claim 1, wherein each of the plurality of lens portions has a portion of its periphery that is arc-shaped in a plan view.

3. Multiple mounting bodies on which the aforementioned multiple semiconductor laser elements are arranged, One or more relay members in which the semiconductor laser element is not arranged, The system comprises a plurality of wires for electrically connecting the plurality of semiconductor laser elements to the substrate, The light-emitting device according to claim 1 or 2, wherein the plurality of wires include a wire that is joined to the relay member.

4. The light-emitting device according to claim 3, wherein the upper surface of the aforementioned mounting body on which the semiconductor laser element is arranged and the upper surface of the relay member to which the wire is joined are located at substantially the same height.

5. The light-emitting device according to claim 3 or 4, wherein the substrate has a first side surface and a second side surface, each of which is a side surface of the recess and faces each other in the first direction, a first wiring which is a wiring provided on the first side surface, and a second wiring which is a wiring provided on the second side surface.

6. The light-emitting device according to claim 5, wherein, among the plurality of semiconductor laser elements, the semiconductor laser element positioned closest to the first side surface is electrically connected to the first wiring via the wire and without the relay member, and is electrically connected to the second wiring via the wire and through the relay member.

7. The light-emitting device according to claim 5 or 6, wherein, among the plurality of semiconductor laser elements, the semiconductor laser element positioned closest to the second side surface is electrically connected to the second wiring via the wire and without the relay member, and is electrically connected to the first wiring via the wire and through the relay member.

8. The light-emitting device according to any one of claims 5 to 7, wherein the plurality of semiconductor laser elements include a semiconductor laser element electrically connected to the first wiring via the wire and the relay member, and a semiconductor laser element electrically connected to the second wiring via the wire and the relay member.

9. The first wiring is a lead that penetrates the first side surface, The light-emitting device according to any one of claims 5 to 8, wherein the second wiring is a lead penetrating the second side surface.

10. The light-emitting device according to any one of claims 3 to 9, wherein the width of the mounting body in the first direction is smaller than the width of the lens portion in the first direction.

11. The light-emitting device according to any one of claims 3 to 10, wherein the width of the relay member in the first direction is smaller than the width of the lens portion in the first direction.

12. The light-emitting device according to any one of claims 3 to 11, wherein the width of the mounting body in a direction perpendicular to the first direction and not in the height direction of the mounting body is smaller than the width of the lens portion in that direction.

13. The light-emitting device according to any one of claims 3 to 12, wherein the width of the relay member in a direction perpendicular to the first direction and not in the height direction of the aforementioned body is smaller than the width of the lens portion in that direction.

Citation Information

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