Light-emitting device

Abstract

To achieve a compact light-emitting device.SOLUTION: A light-emitting device comprises: a substrate that has a top face; a plurality of sub-mounts that have first side faces and second side faces being side faces on the opposite side of the first side faces, and have the first side faces arranged side by side in a first direction on the top face of the substrate, in which their length in the first direction is smaller than their length in a second direction perpendicular to the first direction in top view; a plurality of semiconductor laser elements that individually have light emission surfaces, in which the light emission surfaces are arranged on the sub-mounts different from each other at positions closer to the first side faces than the second side faces; and a plurality of protection elements that are arranged on the sub-mounts different from each other at positions where the distance to the second faces is shorter than the distance from the semiconductor laser elements to the second faces.SELECTED DRAWING: Figure 4

Description

Technical Field

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

Background Art

[0002] Patent Document 1 discloses a semiconductor laser device in which a laser element and a Zener diode electrically connected to the laser element are arranged above a submount. It is also disclosed that by arranging the Zener diode, the laser element can be protected from a surge voltage or the like.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the light-emitting device of 1, there may be a case where a plurality of submounts on which a semiconductor laser element and a protection element are arranged are to be mounted. There is also a need for a small light-emitting device.

Means for Solving the Problems

[0005] The light-emitting device disclosed in the embodiment includes a substrate having an upper surface, a first side surface and a second side surface opposite to the first side surface, the first side surface being arranged side by side in a first direction on the upper surface of the substrate, and the length in a second direction perpendicular to the first direction in a top view being larger than the length in the first direction, a plurality of submounts, each having a light-emitting surface, the light-emitting surface being located closer to the first side surface than the second side surface and being arranged on different ones of the submounts, a plurality of semiconductor laser elements, and each having a distance to the second side surface being shorter than a distance from the semiconductor laser element to the second side surface and being arranged on different ones of the submounts, a plurality of protection elements.

[0006] In at least one of the one or more inventions disclosed by the embodiments, an effect is expected that a small light-emitting device in which a plurality of submounts each having a semiconductor laser element and a protective element disposed therein can be realized.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

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Figure 13

Figure 14

Embodiments for Carrying Out the Invention

[0008] In this specification or the claims, with regard to polygons such as triangles and quadrilaterals, those having been subjected to processing such as rounding, chamfering, corner rounding, or edge rounding at the corners of the polygon are also included in the term "polygon". Further, not limited to the corners (ends of the sides), those having been subjected to processing at the middle part of the sides are also regarded as "polygons". That is, the shapes having been subjected to partial processing while leaving the polygon as a base are included in the interpretation of "polygon" described in this specification and the claims.

[0009] Moreover, not limited to polygons, the same applies to terms representing specific shapes such as trapezoids, circles, and unevenness. The same also applies when dealing with each side forming the shape. That is, even if a side has been subjected to processing at the corner or the middle part, the processed part is included in the interpretation of "side". When distinguishing "polygons" or "sides" without partial processing from the processed shapes, "strict" is added, for example, described as "strict quadrilateral", etc.

[0010] In this specification or the claims, descriptions such as up and down, left and right, front and back, front and rear, near and far are merely stating relative positional, directional, and orientation relationships, and do not necessarily have to match the relationships during use.

[0011] In the drawings, directions such as the X direction, Y direction, and Z direction may be indicated using arrows. The directions of these arrows are consistent among a plurality of drawings related to the same embodiment.

[0012] In addition, in this specification, when describing components or the like, there may be descriptions such as "member" and "part". "Member" shall refer to an object that is physically handled as a single entity. An object that is physically handled as a single entity can also be an object that is handled as a single part in the manufacturing process. On the other hand, "part" shall refer to an object that does not necessarily need to be physically handled as a single entity. For example, "part" is used when partially grasping a part of a single member.

[0013] Note that the above distinction between "member" and "part" does not indicate an intention to consciously limit the scope of rights in the interpretation of the doctrine of equivalents. That is, even if there is a component described as "member" in the claims, the applicant does not recognize that it is essential for the application of the present invention to handle this component physically as a single entity solely based on this fact.

[0014] In addition, in this specification or the claims, when there are a plurality of certain components and they are to be distinguished and expressed separately, there may be cases where "first", "second" are appended to the heads of these components for distinction. Also, there may be cases where the objects to be distinguished are different between this specification and the claims. Therefore, even if a component with the same appendage as in this specification is described in the claims, the object specified by this component may not match between this specification and the claims.

[0015] For example, in this specification, there are components distinguished by appending "first", "second", "third", and when describing the components appended with "first" and "third" in this specification in the claims, for the sake of clarity, in the claims, there may be cases where "first", "second" are appended to distinguish the components. In this case, the components appended with "first", "second" in the claims respectively refer to the components appended with "first", "third" in this specification. Note that the scope of application of this rule is not limited to components, and it is also applied reasonably and flexibly to other objects.

[0016] Hereinafter, embodiments for carrying out the present invention will be described. Furthermore, specific embodiments for carrying out the present invention will be described with reference to the drawings. Note that the embodiments for carrying out the present invention are not limited to this specific embodiment. That is, the illustrated embodiment is not the only form in which the present invention is realized. Note that the sizes and positional relationships of the members shown in each drawing may be exaggerated for convenience of understanding.

[0017] <First Embodiment> The light-emitting device 1 according to the first embodiment will be described. FIGS. 1 to 6 are drawings for explaining an exemplary form of the light-emitting device 1. FIG. 1 is a perspective view of the light-emitting device 1. FIG. 2 is a top view of the light-emitting device 1. FIG. 3 is a cross-sectional view taken along the III-III cross-sectional line of FIG. 2. FIG. 4 is a top view showing the states of the respective components mounted on the substrate 10 of the light-emitting device 1. FIG. 5 is a top view of the submount 30. FIG. 6 is a top view showing a state in which the semiconductor laser element 20 and the protection element 50 are mounted on the submount 30.

[0018] The light-emitting device 1 includes a plurality of components. The plurality of components include a substrate 10, a plurality of semiconductor laser elements 20, a plurality of submounts 30, one or more reflection members 40, a plurality of protection elements 50, a plurality of wirings 60, a lid member 70, and an optical member 80.

[0019] Note that the light-emitting device 1 may further include other components. For example, the light-emitting device 1 may further include a light-emitting element such as a light-emitting diode or a semiconductor laser element separately from the plurality of semiconductor laser elements 20. Also, the light-emitting device 1 may not include some of the plurality of components listed here.

[0020] First, each component will be described.

[0021] (Substrate 10) The substrate 10 has an upper surface 11A, a lower surface 11B, and one or more outer surfaces 11C. In a top view, the outer edge shape of the substrate 10 is rectangular. This rectangle can be a rectangle having a long side and a short side. In the illustrated substrate 10, the long side direction of this rectangle is the same as the X direction, and the short side direction is the same as the Y direction. Note that, in a top view, the outer edge shape of the substrate 10 does not have to be rectangular.

[0022] In the substrate 10, a concave shape is formed. From the upper surface 11A, a concave shape that is recessed downward from the upper surface 11A is formed. A depression is defined by the concave shape of the substrate 10. This depression is surrounded by the upper surface 11A in a top view.

[0023] The inner edge of the upper surface 11A defines the outer edge of the depression. In a top view, the outer edge shape of the depression is rectangular. This rectangle can be a rectangle having a long side and a short side. In the illustrated substrate 10, the long side direction of this rectangle is the same as the X direction, and the short side direction is the same as the Y direction. Note that the outer edge shape of this depression does not have to be rectangular.

[0024] The substrate 10 has a mounting surface 11D and one or more inner surfaces 11E. The mounting surface 11D is located below the upper surface 11A and above the lower surface 11B. The mounting surface 11D is an upper surface. It can be said that the mounting surface 11D is a different upper surface from the upper surface 11A. One or more inner surfaces 11E are located above the mounting surface 11D. One or more inner surfaces 11E intersect the upper surface 11A. The mounting surface 11D and one or more inner surfaces 11E are included in the plurality of surfaces that define the depression of the substrate 10.

[0025] One or more inner surfaces 11E are provided perpendicular to the mounting surface 11D. Here, perpendicular allows a difference of ±3 degrees. Note that the inner surface 11E does not have to be perpendicular to the mounting surface 11D.

[0026] The base body 10 has one or more stepped portions 12C. The stepped portion 12C has an upper surface and an inner surface that intersects the upper surface and extends downward from the upper surface. The upper surface of the stepped portion 12C intersects the inner surface 11E. The inner surface of the stepped portion 12C intersects the mounting surface 11D.

[0027] The stepped portion 12C is formed along a part or all of the inner surface 11E in a top view. The one or more stepped portions 12C are formed inside the upper surface 11A in a top view. The one or more stepped portions 12C are formed inside one or more inner surfaces 11E in a top view.

[0028] The base body 10 may have a plurality of stepped portions 12C. The plurality of stepped portions 12C includes stepped portions 12C formed along the inner surface 11E in a top view. The plurality of stepped portions 12C includes stepped portions 12C formed along the entire inner surface 11E in a top view.

[0029] The plurality of stepped portions 12C includes a stepped portion 12C (hereinafter referred to as the first stepped portion) formed along a certain inner surface 11E (hereinafter referred to as the first inner surface) and a stepped portion 12C (hereinafter referred to as the second stepped portion) formed along another inner surface 11E (hereinafter referred to as the second inner surface) in a top view.

[0030] The first inner surface 11E and the second inner surface 11E face each other. The first stepped portion 12C may be formed only along the first inner surface 11E. The second stepped portion 12C may be formed only along the second inner surface 11E. No stepped portion 12C is provided between the stepped portions 12C formed along the respective inner surfaces 11E facing each other in a top view.

[0031] The base body 10 does not have stepped portions other than the plurality of stepped portions 12C inside the upper surface 11A in a top view, and the plurality of stepped portions 12C can be composed of only two stepped portions 12C. The plurality of stepped portions 12C can be composed of only the first stepped portion 12C and the second stepped portion 12C.

[0032] The plurality of stepped portions 12C include stepped portions 12C formed along the inner surface 11E with a length that is 50% or more and 100% or less of the length of the inner surface 11E in a direction parallel to the mounting surface 11D.

[0033] One or more wiring patterns 13 are provided on the upper surface of the stepped portion 12C. The wiring pattern 13 is electrically connected to other wiring patterns via wiring passing through the inside of the base body 10. The other wiring patterns are provided, for example, on the lower surface of the base body 10. Note that the wiring pattern 13 may be electrically connected to a wiring pattern provided on the upper surface 11A or the outer surface 11C.

[0034] One or more wiring patterns 13 are provided on the upper surfaces of the one or more stepped portions 12C. One or more wiring patterns 13 may be provided on each of the plurality of stepped portions 12C. The base body 10 can have stepped portions 12C with a plurality of wiring patterns 13 provided on the upper surfaces. By providing the wiring pattern 13 on the upper surface of the stepped portion 12C, wiring can be connected at a position higher than the mounting surface 11D. This may facilitate the joining process of the wiring.

[0035] In the base body 10, the location where the wiring pattern 13 is provided does not have to be limited to the stepped portion 12C. It can be said that the base body 10 has a wiring portion provided for electrical connection. In the illustrated base body 10, the stepped portion 12C is also a wiring portion.

[0036] The base body 10 can be formed using ceramic as the main material. Also, the base body 10 may be formed by joining a bottom member having a mounting surface 11D and formed using metal or a composite containing metal as the main material, and a frame member having a wiring pattern 13 and formed using ceramic as the main material.

[0037] Here, the main material refers to the material that occupies the largest proportion of the mass or volume in the object formation. When the object formation is formed from one material, that material is the main material. That is, for a certain material to be the main material includes the fact that the proportion occupied by that material can be 100%.

[0038] Examples of ceramics include aluminum nitride, silicon nitride, aluminum oxide, silicon carbide, etc. Examples of metals include copper, aluminum, iron, etc. Alternatively, as composites containing metals, copper molybdenum, copper-diamond composite materials, copper tungsten, etc. can be used.

[0039] (Semiconductor laser element 20) The semiconductor laser element 20 has a light-emitting surface that emits light. The semiconductor laser element 20 has an upper surface, a lower surface, and a plurality of side surfaces. The upper surface or side surface of the semiconductor laser element 20 serves as the light-emitting surface. The shape of the upper surface of the semiconductor laser element 20 is a rectangle having a long side and a short side. Note that the shape of the upper surface of the semiconductor laser element 20 does not have to be a rectangle.

[0040] The semiconductor laser element 20 is a single-emitter semiconductor laser element. Also, the semiconductor laser element 20 can be a multi-emitter semiconductor laser element having a plurality of emitters. When a multi-emitter semiconductor laser element is adopted for the semiconductor laser element 20, the number of emitters is preferably two. Considering that the semiconductor laser element 20 may become larger as the number of emitters increases and the influence of heat dissipation, etc., a semiconductor laser element with an appropriate number of emitters can be adopted.

[0041] For the semiconductor laser element 20, for example, a semiconductor laser element that emits blue light or a semiconductor laser element that emits green light can be adopted. Also, a semiconductor laser element that emits red light may be adopted for the semiconductor laser element 20. Alternatively, a semiconductor laser element that emits light of other colors may be adopted for the semiconductor laser element 20.

[0042] Here, blue light refers to light whose emission peak wavelength is within the range of 420 nm to 494 nm. Green light refers to light whose emission peak wavelength is within the range of 495 nm to 570 nm. Red light refers to light whose emission peak wavelength is within the range of 605 nm to 750 nm.

[0043] The semiconductor laser element 20 has a rectangular outer shape with one pair of opposite sides being long sides and the other pair of opposite sides being short sides in a top view. The light (laser light) emitted from the semiconductor laser element 20 has a spread. Also, divergent light is emitted from the emission end face (light emission surface) of the semiconductor laser element 20.

[0044] The light emitted from the semiconductor laser element 20 forms an elliptical far-field pattern (hereinafter referred to as "FFP") on a plane parallel to the light emission end face. The FFP is the shape and light intensity distribution of the emitted light at a position away from the emission end face.

[0045] Here, the light passing through the center of the elliptical shape of the FFP, in other words, the light with the peak intensity in the light intensity distribution of the FFP, is called the light traveling along the optical axis or the light passing through the optical axis. Also, in the light intensity distribution of the FFP, the light having an intensity of 1 / e 2 or more of the peak intensity value is called the light of the main part.

[0046] The shape of the FFP of the light emitted from the semiconductor laser element 20 is an elliptical shape in which the stacking direction is longer than the direction perpendicular to the stacking direction on a plane parallel to the light emission end face. The stacking direction is the direction in which a plurality of semiconductor layers including the active layer are stacked in the semiconductor laser element 20. The direction perpendicular to the stacking direction can also be called the plane direction of the semiconductor layer. Also, the major axis direction of the elliptical shape of the FFP can be called the fast axis direction of the semiconductor laser element 20, and the minor axis direction can be called the slow axis direction of the semiconductor laser element 20.

[0047] Based on the light intensity distribution of the FFP, 1 / e of the peak light intensity 2The angle at which the light with the light intensity spreads is defined as the light divergence angle of the semiconductor laser element 20. The light divergence angle is 1 / e of the peak light intensity 2 In addition to the light intensity of, for example, it may be obtained from the light intensity at half the peak light intensity. In the description of this specification, when simply referring to the "light divergence angle", it refers to the light divergence angle at the light intensity of 1 / e 2 of the peak light intensity. It can be said that the divergence angle in the fast axis direction is larger than the divergence angle in the slow axis direction.

[0048] Examples of the semiconductor laser element 20 that emits blue light or the semiconductor laser element 20 that emits green light include a semiconductor laser element 20 containing a nitride semiconductor. As the nitride semiconductor, for example, GaN, InGaN, and AlGaN can be used. Examples of the semiconductor laser element 20 that emits red light include those containing InAlGaP-based, GaInP-based, GaAs-based, and AlGaAs-based semiconductors.

[0049] (Submount 30) The submount 30 has an upper surface 31, a lower surface, and one or more side surfaces 32. The submount 30 has an outer shape in which the length in one direction is larger than the length in the direction perpendicular thereto in a top view. The upper surface 31 has a rectangular shape. The upper surface 31 can have a rectangular shape with a short side and a long side.

[0050] The submount 30 is configured in the shape of a rectangular parallelepiped. The distance between the upper surface 31 and the lower surface of the submount 30 is smaller than the distance between the other two opposing surfaces. The distance between the upper surface 31 and the lower surface is referred to as the thickness of the submount 30. Note that the shape of the submount 30 does not have to be limited to a rectangular parallelepiped.

[0051] An arrangement region 33 is provided on the upper surface 31. Other components are arranged in the arrangement region 33. The arrangement region 33 secures a space for arranging other components. The shape of the arrangement region 33 corresponds to the shape of the components arranged therein. A plurality of arrangement regions 33 are provided on the upper surface 31.

[0052] The length of the short side on the upper surface 31 is 500 μm or more and 1500 μm or less. The length of the long side on the upper surface 31 is 1000 μm or more and 3000 μm or less. The thickness of the submount 30 is 200 μm or more and 500 μm or less. The length of the long side of the upper surface 31 is 150% or more and 300% or less of the length of the short side.

[0053] The submount 30 can be formed using, for example, silicon nitride, aluminum nitride, or silicon carbide. Also, a metal film for bonding to other components is provided in the placement region 33.

[0054] (Reflection member 40) The reflection member 40 has a light reflection surface that reflects light. Also, the light reflection surface is inclined with respect to the lower surface. That is, the arrangement relationship of the light reflection surface when viewed from the lower surface is neither perpendicular nor parallel. The straight line connecting the lower end and the upper end of the light reflection surface is inclined with respect to the lower surface of the reflection member 40. The angle of the light reflection surface with respect to the lower surface, or the angle of the straight line connecting the lower end and the upper end of the light reflection surface with respect to the lower surface, shall be called the inclination angle of the light reflection surface.

[0055] In the illustrated reflection member 40, the light reflection surface is a plane and forms an inclination angle of 45 degrees with respect to the lower surface of the reflection member 40. Note that the light reflection surface does not have to be a plane and may be, for example, a curved surface. Also, the inclination angle of the light reflection surface does not have to be 45 degrees.

[0056] For the main material of the reflection member 40, glass, metal, etc. can be used. The main material is preferably a material that is resistant to heat. For example, glass such as quartz or BK7 (borosilicate glass), or metal such as aluminum can be used. The reflection member 40 can also be formed using Si as the main material. If the main material is a reflective material, the light reflection surface can be formed from the main material. When forming the light reflection surface separately from the main material, the light reflection surface can be formed using, for example, metals such as Ag, Al, or dielectric multilayer films such as Ta2O5 / SiO2, TiO2 / SiO2, Nb2O5 / SiO2.

[0057] On the light-reflecting surface, the reflectivity with respect to the peak wavelength of the light irradiated on the light-reflecting surface is 90% or more. Further, this reflectivity may be 95% or more. Also, this reflectivity can be made 99% or more. The light reflectivity is 100% or less or less than 100%.

[0058] (Protective element 50) The protective element 50 is for preventing an excessive current from flowing through a specific element (for example, a semiconductor laser element) and causing it to be damaged. Examples of the protective element 50 include a Zener diode. Also, as the Zener diode, one formed of Si can be adopted.

[0059] (Wiring 60) The wiring 60 is a linear conductive material with both ends as joints. The joints at both ends become the joining parts with other components. The wiring 60 is, for example, a metal wire. For the metal, for example, gold, aluminum, silver, copper, etc. can be used.

[0060] (Cover member 70) The cover member 70 has a lower surface and an upper surface and is configured in the shape of a rectangular parallelepiped flat plate. Note that it does not have to be a rectangular parallelepiped. The cover member 70 has light-transmitting properties for transmitting light. Here, the light-transmitting property means that the transmittance with respect to light is 80% or more. Note that it does not have to have a transmittance of 80% or more for light of all wavelengths. The cover member 70 may have a non-light-transmitting region (a region that does not have light-transmitting properties) in part.

[0061] The cover member 70 is formed using glass as the main material. The main material forming the cover member 70 is a material having high light-transmitting properties. The cover member 70 is not limited to glass, and for example, it may be formed using sapphire as the main material.

[0062] (Optical member 80) The optical member 80 has an upper surface, a lower surface, and side surfaces. The optical member 80 gives optical actions such as reflection, transmission, and refraction, and optical actions such as focusing, diffusion, and collimation to the incident light.

[0063] The optical member 80 may have one or more lens surfaces. The one or more lens surfaces are provided on the upper surface side of the optical member 80. Note that they may be provided on the lower surface side of the optical member 80. The upper and lower surfaces are flat. The one or more lens surfaces intersect the upper surface. The one or more lens surfaces are surrounded by the upper surface in a top view. In a top view, the optical member 80 has a rectangular outer shape. The lower surface of the optical member 80 is rectangular.

[0064] The portion of the optical member 80 that overlaps with the one or more lens surfaces in a top view is defined as the lens portion. In the optical member 80, the portion that overlaps with the upper surface in a top view is defined as the non-lens portion. When the lens portion is bisected by a virtual plane including the upper surface, the lens surface side is defined as the lens-shaped portion, and the lower surface side is defined as the flat-plate-shaped portion. The lower surface of the lens portion is a part of the lower surface. In the optical member 80, the lower surface is composed of the lower surface of the lens portion and the lower surface of the non-lens portion.

[0065] The illustrated optical member 80 has a plurality of lens surfaces. Further, the plurality of lens surfaces are formed continuously in one direction. The optical member 80 has five lens surfaces, and the vertices of these five lens surfaces are formed so as to be on a straight line. This straight line is in the same direction as the X direction.

[0066] Here, in a top view, the direction in which the plurality of lens surfaces are arranged is defined as the connecting direction. In a top view, the length of the plurality of lens surfaces in the connecting direction is greater than the length in the direction perpendicular to this direction. In the illustrated optical member 80, the connecting direction is the same direction as the X direction.

[0067] The optical member 80 has high light transmittance. The optical member 80 has high light transmittance in both the lens portion and the non-lens portion. Also, the optical member 80 as a whole has high light transmittance. The optical member 80 can be formed using, for example, glass such as BK7.

[0068] Next, the light-emitting device 1 including the above-described components will be described. In the following description of the light-emitting device 1, as long as it is consistent with the drawings related to the light-emitting device 1, the description of a single component also applies to each of the plurality of identical components. That is, when there are a plurality of identical components in the drawing and the description of a single component applies to each of the plurality of identical components in the drawing, this description is also valid for each of the plurality of identical components.

[0069] (Light-emitting device 1) In the light-emitting device 1, the semiconductor laser element 20 is mounted on the submount 30. The semiconductor laser element 20 is disposed on the upper surface 31 of the submount 30. The semiconductor laser element 20 is disposed within the arrangement region 33 provided on the upper surface 31. The semiconductor laser element 20 emits blue light.

[0070] The plurality of semiconductor laser elements 20 are disposed on different submounts 30. All of the plurality of semiconductor laser elements 20 emit light of the same color. Note that a light-emitting element may be further disposed on the submount 30 on which the semiconductor laser element 20 is disposed. Considering heat dissipation and the like, it may be desirable that no light-emitting element is disposed on one submount 30 other than one semiconductor laser element 20.

[0071] The semiconductor laser element 20 is disposed such that its light-emitting surface is located in the vicinity of the side surface 32 of the submount 30. Here, the side surface 32 located in the vicinity of the light-emitting surface is referred to as the first side surface 32A. Also, the side surface 32 of the submount 30 on the opposite side to the first side surface 32A is referred to as the second side surface 32B. The first side surface 32A is the side surface 32 that intersects the short side of the upper surface 31. The second side surface 32B is the side surface 32 that intersects the short side that forms a pair with the short side at which the first side surface 32A and the upper surface 31 intersect. The semiconductor laser element 20 is disposed on the submount 30 at a position where its light-emitting surface is closer to the first side surface 32A than the second side surface 32B.

[0072] In a top view, the semiconductor laser element 20 is arranged such that a virtual straight line L1 passing through the center of the short side of the upper surface 31 and parallel to the long side passes through both the light emitting surface of the semiconductor laser element 20 and the side surface opposite to the light emitting surface. Hereinafter, the virtual straight line is referred to as a "virtual line".

[0073] In the light emitting device 1, the protection element 50 is mounted on the submount 30. The protection element 50 is arranged on the upper surface 31 of the submount 30. The protection element 50 is arranged within an arrangement region 33 provided on the upper surface 31. The protection element 50 is arranged on the submount 30 on which the semiconductor laser element 20 is arranged. A plurality of protection elements 50 are arranged on different submounts 30.

[0074] Regarding the semiconductor laser element 20 and the protection element 50 arranged on the submount 30, the protection element 50 is arranged on the submount 30 at a position where the distance from the protection element 50 to the second side surface 32B is shorter than the distance from the semiconductor laser element 20 to the second side surface 32B. The longest distance from the second side surface 32B to the protection element 50 is shorter than the shortest distance from the second side surface 32B to the semiconductor laser element 20. The protection element 50 is arranged in the vicinity of the second side surface 32B.

[0075] The protection element 50 is arranged at a position where the virtual line L1 does not pass through in a top view. Regarding the semiconductor laser element 20 and the protection element 50 arranged on the submount 30, the protection element 50 is arranged at a position where a virtual line L2 passing through the center of the length in a direction parallel to the light emitting surface of the semiconductor laser element 20 and perpendicular to the light emitting surface does not pass through in a top view. By arranging the protection element 50 at such a position, it is possible to make it less susceptible to the influence of light leaking from the side surface opposite to the light emitting surface.

[0076] The arrangement region 33 where the semiconductor laser element 20 is disposed is different from the arrangement region 33 where the protection element 50 is disposed, and they do not overlap in a top view. Here, the former arrangement region 33 is referred to as the first arrangement region 33A, and the latter arrangement region 33 is referred to as the second arrangement region 33B. In a top view, the first arrangement region 33A and the second arrangement region 33B are provided such that there is a virtual line L3 passing through the first arrangement region 33A and the second arrangement region 33B in a direction parallel to the long side of the upper surface 31. Thereby, the length of the short side of the upper surface 31 can be reduced.

[0077] Note that in the submount 30, the first arrangement region 33A and the second arrangement region 33B may be realized by one arrangement region 33 that is partially connected. In this case, the boundary of the first arrangement region 33A and the boundary of the second arrangement region 33B may be substantially determined. That is, taking into account component tolerances and mounting accuracy, the minimum area to be secured for arranging the semiconductor laser element 20 is defined as the first arrangement region 33A, and the minimum area to be secured for arranging the protection element 50 can be defined as the second arrangement region 33B.

[0078] In the light-emitting device 1, the submount 30 is mounted on the base body 10. The submount 30 is disposed on the mounting surface 11D of the base body 10. A plurality of submounts 30 are arranged side by side on the mounting surface 11D. The plurality of submounts 30 are arranged side by side in the longitudinal direction of the base body 10. The plurality of submounts 30 are arranged side by side in the long side direction of the base body 10.

[0079] Here, the direction in which the plurality of submounts 30 are arranged in a top view is referred to as the first direction. In the light-emitting device 1, the plurality of semiconductor laser elements 20 are arranged side by side in the first direction. In the illustrated light-emitting device 1, the first direction is the same direction as the X direction. Also, in a top view, the direction parallel to the light-emitting surface of the semiconductor laser element 20 disposed on the submount 30 is the same direction as the X direction.

[0080] The plurality of submounts 30 are arranged such that the first side surfaces 32A are aligned in the first direction. The plurality of semiconductor laser elements 20 are arranged such that the light emitting surfaces are aligned in the first direction. In a top view, the length of the submount 30 in the second direction (hereinafter referred to as the second direction), which is perpendicular to the first direction, is larger than the length in the first direction. The length of the submount 30 in the second direction is 150% or more and 300% or less of the length in the first direction. In a top view, the side where the upper surface 31 of the submount 30 intersects the first side surface 32A is parallel to the first direction.

[0081] The plurality of submounts 30 are arranged at intervals of 50 μm or more and 300 μm or less in the first direction. The maximum value of the intervals between adjacent submounts 30 among the plurality of submounts 30 is 50% or less of the length of the submount 30 in the first direction. The length of the submount 30 in the first direction is 2.5 times or more and 5 times or less the minimum value of the intervals between adjacent submounts 30 among the plurality of submounts 30. By defining the size and arrangement intervals of the submount 30 so as to satisfy one or more of these conditions, in a small light emitting device, more submounts 30 on which the semiconductor laser elements 20 are arranged can be arranged in the first direction.

[0082] In a top view, the distance from the long side of the upper surface 31 to the first arrangement region 33A in the region where the protection element 50 is arranged among the regions obtained by bisecting the upper surface 31 by the virtual line L2 is smaller than the distance from the second side surface 32B to the first arrangement region 33A. Furthermore, the distance from this long side to the first arrangement region 33A is smaller than the length of the second arrangement region 33B in the second direction. By reducing the length of the submount 30 in the short side direction so as to satisfy such conditions, more submounts 30 can be arranged in the small light emitting device 1.

[0083] In a top view, the distance from the long side of the upper surface 31 to the first placement region 33A in the region of the upper surface 31 where the protection element 50 is disposed among the regions bisected by the virtual line L2 is smaller than the length of the second placement region 33B in the first direction. Thereby, the length of the submount 30 in the short side direction can be reduced, and in a small light-emitting device, more submounts 30 can be arranged.

[0084] Regarding the submount 30 and the semiconductor laser element 20 disposed on the submount 30, in a top view, the length of the short side of the upper surface 31 is 300% or more and 600% or less of the length in the direction parallel to the light emitting surface of the semiconductor laser element 20. Alternatively, in a top view, the length of the submount 30 in the first direction is 300% or more and 600% or less of the length of the semiconductor laser element 20 in the first direction.

[0085] Regarding the submount 30 and the protection element 50 disposed on the submount 30, in a top view, the length of the short side of the upper surface 31 is 200% or more and 500% or less of the length of the protection element 50 in the direction parallel to the light emitting surface of the semiconductor laser element 20. Alternatively, in a top view, the length of the submount 30 in the first direction is 200% or more and 500% or less of the length of the protection element 50 in the first direction.

[0086] Regarding the submount 30, the semiconductor laser element 20 disposed on the submount 30, and the protection element 50, in a top view, the length of the submount 30 in the first direction is 1.5 times or more and 2.5 times or less the sum of the length of the semiconductor laser element 20 in the first direction and the length of the protection element 50 in the first direction. By defining the length of the submount 30 in the first direction so as to satisfy one or more of these conditions, more submounts 30 on which the semiconductor laser elements 20 are disposed can be arranged in the first direction.

[0087] Regarding the submount 30 and the semiconductor laser element 20 disposed on the submount 30, in a top view, the length of the long side of the upper surface 31 is 105% or more and 150% or less of the length in the direction perpendicular to the light emitting surface of the semiconductor laser element 20. Alternatively, in a top view, the length of the submount 30 in the second direction is 105% or more and 150% or less of the length of the semiconductor laser element 20 in the second direction.

[0088] Regarding the submount 30, the semiconductor laser element 20, and the protective element 50 disposed on the submount 30, in a top view, the length of the submount 30 in the second direction is larger than the sum of the length of the semiconductor laser element 20 in the second direction and the length of the protective element 50 in the second direction by 150 μm or more and 500 μm or less. Thereby, the size of the submount 30 in the second direction can be suppressed, and the light emitting device 1 can be manufactured in a small size.

[0089] In the illustrated light emitting device 1, a light emitting device is disclosed in which five submounts 30 are arranged side by side in the first direction as a plurality of submounts 30. Thus, in the light emitting device 1, the plurality of submounts 30 can include five or more submounts.

[0090] Further, in the illustrated light emitting device 1, a light emitting device is disclosed in which the plurality of semiconductor laser elements 20 are composed of the same number of semiconductor laser elements 20 as the number of submounts 30 disposed on the mounting surface 11D of the substrate 10. Furthermore, a light emitting device having no light emitting element including a semiconductor laser element other than the plurality of semiconductor laser elements 20 is disclosed.

[0091] In the light emitting device 1, the light emitting surfaces of the plurality of semiconductor laser elements 20 face the side respectively. The light emitting surfaces of the plurality of semiconductor laser elements 20 face the same direction respectively. Light traveling laterally from the light emitting surface of the semiconductor laser element 20 is emitted. From the light emitting surface of the semiconductor laser element 20, light of FFP with the direction perpendicular to the mounting surface 11D as the fast axis direction is emitted. For any of the semiconductor laser elements 20, the divergence angle in the slow axis direction is 20 degrees or less. Note that the divergence angle is an angle greater than 0 degrees.

[0092] In the light-emitting device 1, one or a plurality of reflecting members 40 are arranged on the base 10. The reflecting member 40 is arranged on the mounting surface 11D. The reflecting member 40 has a light-reflecting surface. The light emitted from the plurality of semiconductor laser elements 20 is reflected by one or a plurality of light-reflecting surfaces. The light-reflecting surface is inclined at an angle of 45 degrees with respect to the traveling direction of the light passing through the optical axis. The light reflected by the light-reflecting surface travels upward. The light-reflecting surface of the reflecting member 40 is irradiated with the light of one or a plurality of main portions.

[0093] The reflecting member 40 can be provided one-to-one for the semiconductor laser element 20. That is, the same number of reflecting members 40 as the number of semiconductor laser elements 20 are arranged. The plurality of reflecting members 40 are arranged side by side in the first direction in a top view. Any of the reflecting members 40 has the same size and shape. The light-reflecting surface of the reflecting member 40 reflects 90% or more of the light of the irradiated main portion. Note that one reflecting member 40 may be provided for the plurality of semiconductor laser elements 20. Also, one reflecting member 40 may be provided for all the semiconductor laser elements 20. Alternatively, the light-emitting device 1 may not have the reflecting member 40.

[0094] In the light-emitting device 1, the wiring 60 is joined to the wiring pattern 13. The light-emitting device 1 includes a plurality of wirings 60. The plurality of wirings 60 electrically connect one or a plurality of semiconductor laser elements 20 to the base 10.

[0095] In the light-emitting device 1, the lid member 70 is arranged on the upper surface of the base 10. Also, the lid member 70 is located above the stepped portion 12C. Also, by joining the lid member 70, a closed space surrounded by the base 10 and the lid member 70 is created. This space is the space where the semiconductor laser element 20 is arranged.

[0096] By joining the lid member 70 to the base body 10 in a predetermined atmosphere, a hermetically sealed closed space is created. By hermetically sealing the space in which the semiconductor laser element 20 is disposed, quality degradation due to dust collection can be suppressed. The lid member 70 has translucency with respect to the light emitted from the semiconductor laser element 20. 90% or more of the main part of the light emitted from the semiconductor laser element 20 passes through the lid member 70 and is emitted to the outside.

[0097] The optical member 80 is disposed above the lid member 70. The optical member 80 is joined to the lid member 70. A plurality of lights emitted from the lid member 70 are incident on the incident surface of the optical member 80. The light incident on the incident surface of the optical member 80 is emitted from the lens surface.

[0098] In a top view, the optical member 80 is arranged such that each of the plurality of lens surfaces overlaps with a different semiconductor laser element 20. From each of the one or more lens surfaces, the main part of the light emitted from different semiconductor laser elements 20 is emitted. One semiconductor laser element 20 corresponds to one lens surface, and light from the corresponding semiconductor laser element 20 is emitted from each lens surface.

[0099] <Second Embodiment> The light-emitting device 2 according to the second embodiment will be described. FIGS. 1, 2, and 5 to 8 are drawings for explaining an exemplary form of the light-emitting device 2. FIG. 1 is a perspective view of the light-emitting device 2. FIG. 2 is a top view of the light-emitting device 2. FIG. 5 is a top view of the submount 30. FIG. 6 is a top view showing a state in which the semiconductor laser element 20 and the protection element 50 are mounted on the submount 30. FIG. 7 is a cross-sectional view taken along the VII-VII cross-section line of FIG. 1. FIG. 8 is a top view showing the states of the components mounted on the base body 10 of the light-emitting device 1.

[0100] The light-emitting device 2 includes a plurality of components. The plurality of components include a substrate 10, a plurality of semiconductor laser elements 20, a plurality of submounts 30, one or more reflecting members 40, a plurality of protective elements 50, a plurality of wirings 60, a lid member 70, and an optical member 80. Note that the light-emitting device 2 may include other components as well.

[0101] These components are common to the first embodiment. Therefore, the description of each component is as described in the first embodiment. Hereinafter, the light-emitting device 2 will be described. The light-emitting device 2 has features different from those of the light-emitting device 1 of the first embodiment, but also has common parts. Among the contents described for the light-emitting device 1 in the first embodiment, the contents that do not cause inconsistencies based on FIGS. 1, 2, and 5 to 8 also apply to the light-emitting device 2 in the same manner.

[0102] (Light-emitting device 2) In the light-emitting device 2, the plurality of semiconductor laser elements 20 include a first semiconductor laser element 20A and a second semiconductor laser element 20B whose peak wavelengths of light emitted from the light-emitting surfaces are different from each other. The light-emitting device 2 has a plurality of first semiconductor laser elements 20A. The light-emitting device 2 has a plurality of second semiconductor laser elements 20B.

[0103] The peak wavelength of light in the first semiconductor laser element 20A is at least 20 nm smaller than the peak wavelength of light in the second semiconductor laser element 20B. The color of the light emitted from the first semiconductor laser element 20A is different from the color of the light emitted from the second semiconductor laser element 20B. In the illustrated light-emitting device 2, the first semiconductor laser element 20A emits blue light, and the second semiconductor laser element 20B emits green light.

[0104] The length of the first semiconductor laser element 20A in the direction parallel to the light emitting surface is 95% or more and 105% or less of the length of the second semiconductor laser element 20B in the direction parallel to the light emitting surface. The plurality of semiconductor laser elements 20 can be aligned with semiconductor laser elements having approximately the same length in the direction parallel to the light emitting surface. Thereby, for any of the semiconductor laser elements 20, a submount 30 having the same size and shape can be used.

[0105] The plurality of first semiconductor laser elements 20A are arranged side by side in the first direction. The plurality of second semiconductor laser elements 20B are arranged side by side in the first direction. In a top view, on the mounting surface 11D, the first semiconductor laser elements 20A are arranged in one of the regions bisected by an imaginary line L4 parallel to the second direction, and the second semiconductor laser elements 20B are arranged in the other. At this time, no second semiconductor laser element 20B is arranged in one region, and no first semiconductor laser element 20A is arranged in the other region.

[0106] The base 10 has, in a top view, two wiring portions that face each other in the first direction and in which a plurality of semiconductor laser elements 20 are arranged therebetween. In one of the two wiring portions, a wiring pattern 13 for electrically connecting the first semiconductor laser element 20A is provided, and in the other, a wiring pattern 13 for electrically connecting the second semiconductor laser element 20B is provided.

[0107] The plurality of wirings 60 include a plurality of first wirings 60A for electrically connecting the plurality of first semiconductor laser elements 20A and a plurality of second wirings 60B for electrically connecting the plurality of second semiconductor laser elements 20B. In the light emitting device 2, the plurality of first semiconductor laser elements 20A are electrically connected in series, and the plurality of second semiconductor laser elements 20B are electrically connected in series.

[0108] The plurality of first wirings 60A includes first wirings 60A joined to the wiring portion of the substrate 10 and the first semiconductor laser element 20A closest to this wiring portion or the submount 30 on which this first semiconductor laser element 20A is disposed. The plurality of first wirings 60A also includes first wirings 60A joined to the wiring portion of the substrate 10 and the first semiconductor laser element 20A farthest from this wiring portion or the submount 30 on which this first semiconductor laser element 20A is disposed. Of these two first wirings 60A, one first wiring 60A is joined to the wiring portion in one of the regions bisected by an imaginary line L5 parallel to the first direction passing through the side surface on the side opposite to the light emitting surface of the first semiconductor laser element 20A in a top view, and the other first wiring 60A is joined to the wiring portion in the other region.

[0109] The plurality of first wirings 60A includes first wirings 60A joined to the wiring portion of the substrate 10 and the submount 30 on which the first semiconductor laser element 20A farthest from this wiring portion is disposed. This first wiring 60A is joined to the submount 30 in the region where the protective element 50 is disposed among the regions bisected by the imaginary line L5 in a top view. By using this region for the joining of the wiring 60, the size of the submount 30 can be suppressed to be small, and a small light emitting device can be realized.

[0110] The plurality of second wirings 60B includes second wirings 60B joined to the wiring portion of the substrate 10 and the second semiconductor laser element 20B closest to this wiring portion or the submount 30 on which this second semiconductor laser element 20B is disposed. The plurality of second wirings 60B also includes second wirings 60B joined to the wiring portion of the substrate 10 and the second semiconductor laser element 20B farthest from this wiring portion or the submount 30 on which this second semiconductor laser element 20B is disposed. Of these two second wirings 60B, one second wiring 60B is joined to the wiring portion in one of the regions bisected by an imaginary line L6 parallel to the first direction passing through the side surface on the side opposite to the light emitting surface of the second semiconductor laser element 20B in a top view, and the other second wiring 60B is joined to the wiring portion in the other region.

[0111] The plurality of second wirings 60B includes second wirings 60B joined to the wiring portion of the substrate 10 and the submount 30 on which the second semiconductor laser element 20B farthest from this wiring portion is disposed. This second wiring 60B is joined to the submount 30 in a region where the protection element 50 is disposed among the regions bisected by the virtual line L6 in a top view. By using this region for joining the wiring 60, the size of the submount 30 can be suppressed to be small, and a small light-emitting device can be realized.

[0112] In the light-emitting device 2, there is no wiring 60 passing through the virtual line L4 in a top view.

[0113] Thus, in the light-emitting device 2, light of a plurality of colors can be emitted. Further, since power can be supplied separately to the first semiconductor laser element 20A and the second semiconductor laser element 20B, control of a current or voltage suitable for each can be achieved.

[0114] <Third Embodiment> The light-emitting device 3 according to the third embodiment will be described. FIGS. 1, 2, 5, 6, and 9 to 12 are drawings for explaining an exemplary form of the light-emitting device 3. FIG. 1 is a perspective view of the light-emitting device 3. FIG. 2 is a top view of the light-emitting device 3. FIG. 5 is a top view of the first submount 30A. FIG. 6 is a top view showing a state in which the semiconductor laser element 20 and the protection element 50 are mounted on the first submount 30A. FIG. 9 is a cross-sectional view taken along the IX-IX cross-sectional line of FIG. 1. FIG. 10 is a top view showing the state of each component mounted on the substrate 10 of the light-emitting device 1. FIG. 11 is a top view of the second submount 30B. FIG. 12 is a top view showing a state in which the semiconductor laser element 20 and the protection element 50 are mounted on the second submount 30B.

[0115] The light-emitting device 3 includes a plurality of components. The plurality of components include a substrate 10, a plurality of semiconductor laser elements 20, a plurality of submounts 30, one or more reflecting members 40, a plurality of protective elements 50, a plurality of wirings 60, a lid member 70, and an optical member 80. In the light-emitting device 3, the plurality of semiconductor laser elements 20 include a first semiconductor laser element 20A and a second semiconductor laser element 20B. Note that the light-emitting device 3 may further include other components.

[0116] The substrate 10, the semiconductor laser element 20, the submount 30, the reflecting member 40, the protective element 50, the wiring 60, the lid member 70, and the optical member 80 are the same as those in the first embodiment. Therefore, the description of each component is as described in the first embodiment. Also, the first semiconductor laser element 20A and the second semiconductor laser element 20B are the same as those in the second embodiment.

[0117] Hereinafter, the light-emitting device 3 will be described. The light-emitting device 3 has features different from those of the light-emitting device 1 of the first embodiment and the light-emitting device 2 of the second embodiment, but also has common parts. Among the contents described for the light-emitting device 1 in the first embodiment and the contents described for the light-emitting device 2 in the second embodiment, the contents that do not cause inconsistencies based on FIGS. 1, 2, 5, 6, and 9 to 12 are also applicable to the light-emitting device 3 in the same manner.

[0118] (Light-emitting device 3) In the light-emitting device 3, the plurality of submounts 30 include a first submount 30A and a second submount 30B. The relative arrangement of the second arrangement region 33B with respect to the first arrangement region 33A is different between the first submount 30A and the second submount 30B. The first submount 30A has the second arrangement region 33B provided at a position close to one of the two long sides on the upper surface 31 of the submount 30, and the second submount 30B has the second arrangement region 33B provided at a position close to the other side.

[0119] The length of the short side of the upper surface 31 of the first submount 30A is 95% or more and 105% or less of the length of the short side of the upper surface 31 of the second submount 30B. The length of the long side of the upper surface 31 of the first submount 30A is 95% or more and 105% or less of the length of the long side of the upper surface 31 of the second submount 30B. The first submount 30A and the second submount 30B are of the same size and shape.

[0120] In the light-emitting device 3, the plurality of semiconductor laser elements 20 include a first semiconductor laser element 20A and a second semiconductor laser element 20B. The plurality of submounts 30 include a first submount 30A on which the first semiconductor laser element 20A is disposed and a second submount 30B on which the second semiconductor laser element 20B is disposed.

[0121] The first semiconductor laser element 20A farthest from the wiring portion to which the first wiring 60A is joined is disposed on the first submount 30A. The second arrangement region 33B of the first submount 30A is provided at a position close to the side farther from this wiring portion among the two long sides. The distance from this wiring portion to the position where the first wiring 60A joined to this first submount 30A is joined to the first submount 30A is shorter than the distance from this wiring portion to the second arrangement region 33B of the first submount 30A. By doing so, the length of the wiring 60 can be suppressed and the stability can be improved.

[0122] The second semiconductor laser element 20B farthest from the wiring portion to which the second wiring 60B is joined is disposed on the second submount 30B. The second arrangement region 33B of this second submount 30B is provided at a position close to the side farther from this wiring portion among the two long sides. The distance from this wiring portion to the position where the second wiring 60B joined to this second submount 30B is joined to the second submount 30B is shorter than the distance from this wiring portion to the second arrangement region 33B of this second submount 30B. By doing so, the length of the wiring 60 can be suppressed and the stability can be improved.

[0123] Among the plurality of first semiconductor laser elements 20A, the first semiconductor laser elements 20A other than the first semiconductor laser element 20A that is farthest from the wiring portion to which the first wiring 60A is joined are arranged on the first submount 30A or the second submount 30B. Among the plurality of second semiconductor laser elements 20B, the second semiconductor laser elements 20B other than the second semiconductor laser element 20B that is farthest from the wiring portion to which the second wiring 60B is joined are arranged on the first submount 30A or the second submount 30B.

[0124] All of the plurality of first semiconductor laser elements 20A are arranged on the first submount 30A. All of the plurality of second semiconductor laser elements 20B are arranged on the second submount 30B. In this way, by unifying the submounts 30 used according to the semiconductor laser elements 20, manufacturing becomes easy and productivity can be improved.

[0125] <Fourth Embodiment> The light-emitting device 4 according to the fourth embodiment will be described. FIGS. 1, 2, 5, 6, 13, and 14 are drawings for explaining an exemplary form of the light-emitting device 4. FIG. 1 is a perspective view of the light-emitting device 4. FIG. 2 is a top view of the light-emitting device 4. FIG. 5 is a top view of the first submount 30A. FIG. 6 is a top view showing a state in which the semiconductor laser element 20 and the protection element 50 are mounted on the first submount 30A. FIG. 13 is a cross-sectional view taken along the XIII-XIII cross-sectional line of FIG. 1. FIG. 14 is a top view showing the state of each component mounted on the base 10B of the light-emitting device 1.

[0126] The light-emitting device 4 includes a plurality of components. The plurality of components include a substrate 10B, a plurality of semiconductor laser elements 20, a plurality of submounts 30, one or more reflecting members 40, a plurality of protective elements 50, a plurality of wirings 60, a lid member 70, and an optical member 80. Further, in the light-emitting device 4, the plurality of semiconductor laser elements 20 include a first semiconductor laser element 20A and a second semiconductor laser element 20B. Further, in the light-emitting device 4, the plurality of submounts 30 include a first submount 30A or a second submount 30B. Note that the light-emitting device 4 may include other components in addition to these.

[0127] The semiconductor laser element 20, the submount 30, the reflecting member 40, the protective element 50, the wiring 60, the lid member 70, and the optical member 80 are common to the first embodiment. Therefore, the description of each component is as described in the first embodiment. Further, the first semiconductor laser element 20A and the second semiconductor laser element 20B are common to those in the second embodiment. Further, the first submount 30A and the second submount 30B are common to those in the third embodiment.

[0128] The substrate 10B has characteristics different from those of the substrate 10 of the first embodiment, but also has common parts. Among the contents described for the substrate 10 and the submount 30 in the first embodiment, the contents that do not cause inconsistencies based on FIGS. 13 and 14 also apply to the substrate 10B in the same manner. Hereinafter, the different characteristics of the substrate 10B will be described.

[0129] (Substrate 10B) In the substrate 10B, the first stepped portion 12C is formed along a part or all of the first inner surface 11E and a part of the inner surface 11E (hereinafter referred to as the third inner surface) that intersects the first inner surface 11E. The first stepped portion 12C can be said to be a stepped portion 12C formed integrally along each of the adjacent first inner surface 11E and third inner surface 11E.

[0130] The first stepped portion 12C is formed along all of the inner surfaces 11E among the adjacent inner surfaces 11E that extend in the short side direction of the rectangular outer edge of the base 10B, and a part of the inner surface 11E that extends in the long side direction of this outer edge. The first stepped portion 12C is formed along this inner surface 11E with a length that is 10% or more and less than 50% of the length of the inner surface 11E that extends in this long side direction.

[0131] In the illustrated light-emitting device 4, the first inner surface 11E extends in the short side direction of the rectangular outer edge of the base 10B, and the third inner surface 11E extends in the long side direction. Further, the base 10 does not have a stepped portion 12C formed along the inner surface 11E that faces the third inner surface 11E.

[0132] In the first stepped portion 12C, wiring patterns 13 are provided in each of the portion formed along the inner surface 11E that extends in the short side direction of the rectangular outer edge of the base 10B and the portion formed along the inner surface 11E that extends in the long side direction.

[0133] Hereinafter, the light-emitting device 4 will be described. The light-emitting device 4 has features different from those of the light-emitting device 1 of the first embodiment, the light-emitting device 2 of the second embodiment, and the light-emitting device 3 of the third embodiment, but also has common parts. Among the contents described for the light-emitting device 1 in the first embodiment, the contents described for the light-emitting device 2 in the second embodiment, and the contents described for the light-emitting device 3 in the third embodiment, the contents that do not cause inconsistencies based on FIGS. 1, 2, 5, 6, 13, and 14 also apply to the light-emitting device 4 in the same manner.

[0134] (Light-emitting device 4) In the light-emitting device 4, the plurality of submounts 30 include the first submount 30A or the second submount 30B. Further, the plurality of submounts 30 include the third submount 30C. In the illustrated light-emitting device 4, the plurality of submounts 30 include the second submount 30B and the third submount 30C. Note that the second submount 30B may be replaced with the first submount 30A.

[0135] The length of the long side of the upper surface 31 of the third submount 30C is smaller than the length of the long side of the upper surface 31 of the first submount 30A or the second submount 30B. Hereinafter, the first submount 30A or the second submount 30B will be referred to as the longer submount 30, and the third submount 30C will be referred to as the shorter submount 30 for distinction.

[0136] The plurality of submounts 30 include a plurality of longer submounts 30. The plurality of submounts 30 include a plurality of shorter submounts 30. The shorter submount 30 has the first arrangement region 33A but does not have the second arrangement region 33B. That is, the second arrangement region 33B is not provided in the shorter submount 30. Therefore, the protection element 50 is not arranged on the shorter submount 30. By not providing the second arrangement region 33B, the length of the long side of the upper surface 31 can be made shorter than that of the longer submount 30.

[0137] Regarding the length in the long side direction, the longer submount 30 is larger than the shorter submount 30 in the range of 100 μm or more and 600 μm or less. Thereby, while securing a region for arranging the protection element 50 in the longer submount 30, the enlargement of the substrate 10 can be suppressed, which can contribute to the miniaturization of the light emitting device 1.

[0138] In the light emitting device 4, one of the first semiconductor laser element 20A and the second semiconductor laser element 20B is arranged on the longer submount 30, and the other is arranged on the shorter submount 30. In the illustrated light emitting device 4, the first semiconductor laser element 20A is arranged on the shorter submount 30, and the second semiconductor laser element 20B is arranged on the longer submount 30.

[0139] The shorter submount 30 is arranged on the side of the first step portion 12C, and the longer submount 30 is arranged on the side of the second step portion 12C.

[0140] In relation to the portion formed along the third inner surface 11E of the first step portion 12C, the shorter submount 30 is perpendicular to the third inner surface 11E in top view and is disposed at the position through which the virtual line L7 passing through this portion of the first step portion 12C passes. Further, the longer submount 30 is parallel to the third inner surface 11E in top view and is disposed at the position through which the virtual line L8 passing through this portion of the first step portion 12C passes.

[0141] The semiconductor laser element 20 disposed on the longer submount 30 is not disposed at the position through which the virtual line L8 passes. Further, the protective element 50 disposed on the longer submount 30 is disposed at the position through which the virtual line L8 passes. Thereby, without increasing the size of the base 10B, a region for disposing the protective element 50 on the mounting surface 11D can be secured.

[0142] The protective element 50 that protects the semiconductor laser element 20 disposed on the shorter submount 30 is disposed on the first step portion 12C. One protective element 50 that protects a plurality of semiconductor laser elements 20 disposed on the shorter submount 30 is disposed on the first step portion 12C. The number of protective elements 50 disposed on the first step portion 12C is one. Thereby, the number of protective elements 50 to be used can be reduced as compared with disposing a protective element 50 for each semiconductor laser element 20.

[0143] The plurality of wirings 60 joined to the first step portion 12C include a wiring 60 joined to the shorter submount 30 disposed at the position closest to the first inner surface 11E or the semiconductor laser element 20 disposed on this submount 30, and a wiring 60 joined to the shorter submount 30 disposed at the position farthest from the first inner surface 11E or the semiconductor laser element 20 disposed on this submount 30. In the first step portion 12C, the protective element 50 is disposed between these two wirings 60. The former wiring 60 is joined to the wiring pattern 13 at the portion formed along the first inner surface 11E of the first step portion 12C, and the latter wiring 60 is joined to the wiring pattern 13 at the portion formed along the third inner surface 11E of the first step portion 12C.

[0144] In the light-emitting device 4, the number of the longer submounts 30 arranged on the mounting surface 11D is larger than the number of the shorter submounts 30 arranged on the mounting surface 11D. The number of the longer submounts 30 arranged on the mounting surface 11D is 3 or more.

[0145] When the protection elements 50 are provided for the semiconductor laser elements 20 on a one-to-one basis, if the protection elements 50 are arranged at the step portions 12C, the connection of the wirings 60 with the submounts 30 becomes complicated. However, if the longer submounts 30 are used, since the semiconductor laser elements 20 and the protection elements 50 can be arranged on the submounts 30, the connection of the wirings 60 becomes easy.

[0146] It is considered that the significance of protecting the semiconductor laser elements 20 individually increases as the number of the semiconductor laser elements 20 connected in series increases. On the other hand, if the number of the semiconductor laser elements 20 connected in series is not so large, there is also a concept of protecting them collectively with one protection element 50. According to this concept, it can also be considered that the number of the shorter submounts 30 arranged on the mounting surface 11D is preferably 2 or less.

[0147] From the first inner surface 11E, the distance from the first inner surface 11E to the farthest point in the portion partially provided on the third inner surface 11E of the first step portion 12C is shorter than the distance from the first inner surface 11E to the longer submount 30 arranged at the position closest to the first inner surface 11E. Thereby, the longer submount 30 can be arranged without contacting the first step portion 12C.

[0148] In the light-emitting device 4, the difference between the length in the long-side direction of the longer submount 30 and the length in the long-side direction of the shorter submount 30 is smaller than the length in the direction perpendicular to the third inner surface 11E in the portion formed along the third inner surface 11E of the first step portion 12C. This difference in length is preferably 30% or more and 90% or less of the length in the direction perpendicular to the third inner surface 11E in the portion formed along the third inner surface 11E of the first step portion 12C. Thereby, the effect of providing the step portion 12C partially may become more remarkable.

[0149] The above describes each embodiment of the present invention. However, the light-emitting device according to the present invention is not strictly limited to the light-emitting devices of each embodiment. That is, the present invention can be realized without being limited to the outer shape and structure of the light-emitting device disclosed in each embodiment. The present invention can be applied without necessarily requiring all components to be provided in sufficient quantity. For example, if some of the components of the light-emitting device disclosed in the embodiment are not described in the claims, for those partial components, the freedom of design by those skilled in the art, such as substitution, omission, shape modification, material change, etc., is recognized, and on this basis, it is specified that the invention described in the claims is applicable.

Industrial Applicability

[0150] The light-emitting devices described in each embodiment can be used in projectors, in-vehicle headlights, head-mounted displays, lighting, displays, etc.

Explanation of Signs

[0151] 1, 2, 3, 4 Light-emitting device 10, 10B Substrate 11A Upper surface 11B Lower surface 11C Outer surface 11D Mounting surface 11E Inner surface 12C Step portion 13 Wiring pattern 20 Semiconductor laser element 20A First semiconductor laser element 20B Second semiconductor laser element 30 Submount 31 Upper surface 32 Side surface 32A First side surface 32B Second side surface 33 Arrangement region 33A First arrangement region 33B Second arrangement region 30A First submount 30B Second Submount 30C Third Submount 40 Reflective Member 50 Protective Element 60 Wiring 60A First Wiring 60B Second Wiring 70 Cover Member 80 Optical Member

Claims

1. a base having an upper surface, a first wiring portion, and a second wiring portion; a plurality of submounts each having a first side surface and a second side surface that is a side surface opposite to the first side surface, the first side surfaces being arranged side by side in a first direction on the upper surface of the base, and a length in a second direction perpendicular to the first direction in a top view being greater than a length in the first direction; a plurality of semiconductor laser elements each having a light emitting surface, the light emitting surface being located closer to the first side surface than the second side surface, and the light emitting surface being located on different submounts such that a virtual line passing through a center of the first side surface and parallel to the second direction in a top view passes through the light emitting surface; A plurality of protection elements are disposed on different submounts, each of which is located closer to the second side surface than to the first side surface and is located at a position where the imaginary line does not pass through. Multiple wiring and Equipped with the plurality of semiconductor laser elements include a first semiconductor laser element and a second semiconductor laser element having mutually different peak wavelengths of emitted light, and are disposed between the first wiring portion and the second wiring portion when viewed from above, the plurality of wirings include one or a plurality of first wirings electrically connected to the first semiconductor laser element, and one or a plurality of second wirings electrically connected to the second semiconductor laser element, the one or more first wirings include at least the first wiring bonded to the submount on which the first semiconductor laser element is disposed and the first wiring portion, the one or more second wirings include at least the second wiring bonded to the submount on which the second semiconductor laser element is disposed and the second wiring portion, the plurality of protection elements include a first protection element disposed on the submount on which the first semiconductor laser element is disposed, and a second protection element disposed on the submount on which the second semiconductor laser element is disposed, the first protection element is disposed at a position spaced apart in the first direction from the virtual line based on the submount on which the first semiconductor laser element is disposed, the second protection element is disposed at a position in the first direction away from the imaginary line based on the submount on which the second semiconductor laser element is disposed.

2. a base having an upper surface, a first wiring portion, and a second wiring portion; a plurality of submounts each having a first side surface and a second side surface that is a side surface opposite to the first side surface, the first side surfaces being arranged side by side in a first direction on the upper surface of the base, and a length in a second direction perpendicular to the first direction in a top view being greater than a length in the first direction; a plurality of semiconductor laser elements each having a light emitting surface, the light emitting surface being located closer to the first side surface than the second side surface, and the light emitting surface being located on different submounts such that a virtual line passing through a center of the first side surface and parallel to the second direction in a top view passes through the light emitting surface; A plurality of protection elements are disposed on different submounts, each of which is located closer to the second side surface than to the first side surface and is located at a position where the imaginary line does not pass through. Multiple wiring and Equipped with the plurality of semiconductor laser elements include a first semiconductor laser element and a second semiconductor laser element having mutually different peak wavelengths of emitted light, and are disposed between the first wiring portion and the second wiring portion when viewed from above, the plurality of wirings include one or a plurality of first wirings electrically connected to the first semiconductor laser element, and one or a plurality of second wirings electrically connected to the second semiconductor laser element, the one or more first wirings include at least the first wiring bonded to the submount on which the first semiconductor laser element is disposed and the first wiring portion, the one or more second wirings include at least the second wiring bonded to the submount on which the second semiconductor laser element is disposed and the second wiring portion, the plurality of protection elements include a first protection element disposed on the submount on which the first semiconductor laser element is disposed, and a second protection element disposed on the submount on which the second semiconductor laser element is disposed, the first protection element is disposed at a position spaced apart in the first direction from the virtual line based on the submount on which the first semiconductor laser element is disposed, the second protection element is disposed at a position away from the imaginary line based on the submount on which the second semiconductor laser element is disposed in a direction opposite to the first direction.

3. 3. The light emitting device according to claim 1, wherein the submount on which the first semiconductor laser element is disposed and the submount on which the second semiconductor laser element is disposed have the same size and shape.

4. the plurality of semiconductor laser elements include a plurality of the first semiconductor laser elements, 4. The light-emitting device according to claim 1, wherein the one or more first wirings include the first wiring bonded to the first wiring section and the first semiconductor laser element closest to the first wiring section or the submount on which the first semiconductor laser element is disposed, and the first wiring bonded to the first wiring section and the first semiconductor laser element farthest from the first wiring section or the submount on which the first semiconductor laser element is disposed, and any of the first wirings is the first wiring bonded to the submount on which at least the first semiconductor laser element is disposed and the first wiring section according to claim 1.

5. the plurality of semiconductor laser elements include a plurality of the second semiconductor laser elements, 5. The light-emitting device according to claim 4, wherein the one or more second wirings include the second wiring bonded to the second wiring portion and the second semiconductor laser element closest to the second wiring portion or the submount on which the second semiconductor laser element is disposed, and the second wiring bonded to the second wiring portion and the second semiconductor laser element farthest from the second wiring portion or the submount on which the second semiconductor laser element is disposed, any of the second wirings being the second wiring bonded to the submount on which at least the second semiconductor laser element is disposed and the second wiring portion according to claim 1.

6. The light emitting device according to claim 1 , wherein the first direction is a direction proceeding from the first wiring portion to the second wiring portion.

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