Light-emitting device

Abstract

To realize a light-emitting device with reduced wiring resistance. [Solution] A light emitting device comprising: a plurality of semiconductor laser elements, each having a top surface and a light emitting surface, including a first semiconductor laser element and a second semiconductor laser element; a plurality of protection elements, including a first protection element that protects the first semiconductor laser element and a second protection element that protects the second semiconductor laser element; and a plurality of wirings, including a first wiring bonded to the first protection element and a second wiring bonded to the second protection element, electrically connecting the plurality of semiconductor laser elements and the plurality of protection elements, wherein the first wiring is not bonded to the first semiconductor laser element, and the second wiring is bonded to the top surface of the second semiconductor laser element.

Description

[Technical Field]

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

[0002] Japanese Patent Application Laid-Open No. 2023-88082 discloses a light emitting device in which a plurality of light emitting elements and a plurality of protective elements are arranged on the upper surface of a submount, and these elements are electrically connected by a plurality of wirings. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2023-88082 Summary of the Invention [Problem to be solved by the invention]

[0004] An invention is disclosed that solves the problem of suppressing wiring resistance.

[0005] Alternatively, instead of the above-mentioned problem, an invention is disclosed that solves the problem of easily preventing contact between wirings.

[0006] Alternatively, instead of the above-mentioned problems, an invention is disclosed that solves the problem of achieving stable wiring connections while densely arranging a plurality of semiconductor laser elements.

[0007] This specification also discloses inventions that solve multiple of the above-mentioned problems in a composite manner. [Means for solving the problem]

[0008] The light emitting device disclosed in the embodiment includes a first semiconductor laser element having an upper surface, and a second semiconductor laser element having an upper surface and having a length in the cavity direction larger than that of the first semiconductor laser element, the plurality of semiconductor laser elements each having a light emitting surface, a plurality of protection elements including a first protection element that protects the first semiconductor laser element and a second protection element that protects the second semiconductor laser element, and a plurality of wirings that include a first wiring bonded to the first protection element and a second wiring bonded to the second protection element and are electrically connected to the plurality of semiconductor laser elements and the plurality of protection elements, the first wiring is not bonded to the first semiconductor laser element, and the second wiring is bonded to the upper surface of the second semiconductor laser element.

[0009] In at least one of the one or more inventions disclosed in the embodiments, wiring resistance can be reduced. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view of a light emitting device according to each embodiment. [Figure 2] FIG. 2 is a side view of the light emitting device according to each embodiment. [Figure 3] FIG. 3 is a top view of the light emitting device according to each embodiment. [Figure 4] FIG. 4 is a cross-sectional view of the light emitting device according to each embodiment taken along line IV-IV in FIG. [Figure 5] FIG. 5 is a top view showing the internal structure of the light emitting device according to the first embodiment. [Figure 6A] FIG. 6A is an enlarged view illustrating a wiring connection mode of the light emitting device according to the first embodiment. [Figure 6B] FIG. 6B is a first supplementary diagram for explaining the wiring connection mode of the light emitting device according to the first embodiment. [Figure 6C] FIG. 6C is a second supplementary diagram for explaining the wiring connection mode of the light emitting device according to the first embodiment. [Figure 7] FIG. 7 is a cross-sectional view of a package according to each embodiment. [Figure 8] FIG. 8 is a top view of the base body according to each embodiment. [Figure 9] FIG. 9 is a bottom view of the base body according to each embodiment. [Figure 10] FIG. 10 is a cross-sectional view of the substrate according to each embodiment. [Figure 11] FIG. 11 is a schematic diagram of the semiconductor laser element and the protection element disposed on the submount. [Figure 12] FIG. 12 is a top view showing the internal structure of the light emitting device according to the second embodiment. [Figure 13] FIG. 13 is an enlarged view for explaining the wiring connection mode of the light emitting device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] In this specification and claims, polygons such as triangles and quadrilaterals are referred to as polygons, including shapes in which the corners of the polygons have been rounded, chamfered, corner-cut, rounded, etc. Furthermore, shapes in which processing has been applied not only to the corners (edges of the sides) but also to the middle portions of the sides are also referred to as polygons. In other words, shapes in which partial processing has been applied while retaining the polygonal base are included in the interpretation of "polygon" described in this specification and claims.

[0012] The same applies to words that describe specific shapes, such as trapezoids, circles, and irregularities, not just polygons. The same also applies when dealing with the sides that form the shape. In other words, even if the corners or middle part of a side are processed, the interpretation of "side" includes the processed part. Note that when distinguishing a "polygon" or "side" that has no processing from a processed shape, the word "strict" is added, for example, "strict quadrangle."

[0013] Furthermore, in this specification or the claims, descriptions such as up and down (upper / lower), left and right, front and back, front and back (front / rear), front and back, etc. merely describe the relationship of relative position, orientation, direction, etc., and do not necessarily correspond to the relationship during use.

[0014] 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 multiple drawings relating to the same embodiment. In the drawings, the direction of an arrow marked with X, Y, or Z is the positive direction, and the opposite direction is the negative direction. For example, a direction with X at the end of an arrow is the X direction and the positive direction. In this specification, a direction that is the X direction and the positive direction is referred to as the "positive X direction," and the opposite direction is referred to as the "negative X direction." When referring to the "X direction," it is intended to include both the positive and negative directions. The same applies to the Y and Z directions.

[0015] Furthermore, in this specification, when a certain object is described by specifying "one or more," both the form in which there is one object and the form in which there is multiple objects are described together. Therefore, a description specifying "one or more" supports any of embodiments including one or more objects, embodiments including at least one object, and embodiments including multiple objects.

[0016] Furthermore, in this specification, a description of "one or each" object is a description that compiles a description of one object in an embodiment having one object, a description of one object in an embodiment having multiple objects, and a description of each of the objects in an embodiment having multiple objects. Therefore, a description of "one or each" object supports all of the following: in an embodiment having one object, this one object has the explanatory content; in an embodiment having multiple objects, at least one of these objects has the explanatory content; in an embodiment having multiple objects, each of these multiple objects has the explanatory content; and in an embodiment having one or multiple objects, all of the objects have the explanatory content.

[0017] Furthermore, in this specification, the terms "component" and "part" may be used when describing components, for example. A "component" refers to an object that is handled physically as a single unit. An object that is handled physically as a single unit can also be said to be an object that is handled as a single part in the manufacturing process. On the other hand, a "part" refers to an object that does not need to be handled physically as a single unit. For example, the term "part" is used when referring to a portion of a single component, or when referring to multiple components collectively as a single object.

[0018] The distinction between "component" and "part" above does not indicate a conscious intention to limit the scope of rights in the interpretation of the doctrine of equivalents. In other words, even if a component is described as a "component" in the claims, this does not mean that the applicant recognizes that treating this component as a single physical unit is essential for the application of the present invention.

[0019] Furthermore, in this specification or claims, when there are multiple elements of a certain type and they need to be distinguished from one another, the elements may be prefixed with "first" or "second." Furthermore, the objects distinguished between the specification and the claims may differ. Therefore, even if the claims describe elements with the same prefixes as the specification, the objects identified by these elements may not be the same between the specification and the claims.

[0020] For example, if there are elements in this specification that are distinguished by the notation "first," "second," and "third," and the elements marked "first" and "third" in this specification are described in the claims, the elements may be distinguished by the notation "first" and "second" in the claims for clarity. In this case, the elements marked "first" and "second" in the claims refer to the elements marked "first" and "third" in this specification, respectively. Note that this rule is not limited to elements, and can be applied rationally and flexibly to other objects as well.

[0021] 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 these specific embodiments. In other words, the illustrated embodiments are not the only embodiments in which the present invention can be realized. Note that the sizes and positional relationships of components shown in each drawing may be exaggerated for ease of understanding.

[0022] First Embodiment A light emitting device 1 according to a first embodiment will be described. FIGS. 1 to 11 are diagrams illustrating an exemplary embodiment of the light emitting device 1. FIG. 1 is a perspective view of the light emitting device 1. FIG. 2 is a side view of the light emitting device 1. FIG. 3 is a top view of the light emitting device 1. FIG. 4 is a cross-sectional view of the light emitting device 1 taken along line IV-IV in FIG. 3. FIG. 5 is a top view showing the internal structure of the light emitting device 1. FIG. 6A is an enlarged view illustrating the wiring connection of the light emitting device 1. FIGS. 6B and 6C are supplementary views in which some components or reference numerals have been removed from FIG. 6A and some reference numerals have been written for clarity. FIG. 7 is a cross-sectional view of a package 10 of the light emitting device 1. The cross-sectional view of FIG. 7 corresponds to the cross-section taken along line IV-IV in FIG. 3. FIG. 8 is a top view of a base 11 of the light emitting device 1. FIG. 9 is a bottom view of the base 11. FIG. 10 is a cross-sectional view of the base 11. The cross-sectional view of FIG. 10 corresponds to the cross-section taken along line IV-IV in FIG. 3. FIG. 11 is a schematic diagram of the semiconductor laser element 20 and the protection element 50 arranged on the submount 30. As shown in FIG.

[0023] The light emitting device 1 includes a plurality of components, including a package 10, one or more semiconductor laser elements 20, one or more submounts 30, one or more reflecting members 40, one or more protective elements 50, a plurality of wirings 60, and an optical member 70.

[0024] The light emitting device 1 may include other components. For example, the light emitting device 1 may include a semiconductor laser element in addition to the one or more semiconductor laser elements 20. The light emitting device 1 may not include some of the components listed here.

[0025] First, each component will be described.

[0026] (Package 10) The package 10 includes a base 11 and a lid 14. The lid 14 is joined to the base 11 to form the package 10. An internal space is defined in the package 10 in which other components are placed. This internal space is a closed space surrounded by the base 11 and the lid 14. This internal space can also be a space sealed in a vacuum or airtight state.

[0027] When viewed from above, the outer edge of the package 10 has a rectangular shape. This rectangle can have a long side and a short side. In the illustrated package 10, the long side of the rectangle is oriented in the X direction, and the short side is oriented in the Y direction. However, when viewed from above, the outer edge of the package 10 does not have to have a rectangular shape.

[0028] An internal space in which other components are placed is formed in the package 10. The first upper surface 11A of the package 10 is part of the area that defines the internal space. In addition, each of the inner side surfaces 11E and the lower surface 14B of the package 10 is also part of the area that defines the internal space.

[0029] The base 11 has a first upper surface 11A and a lower surface 11B. The base 11 has a second upper surface 11C. The base 11 has one or more outer surfaces 11D. The base 11 has one or more inner surfaces 11E. The one or more outer surfaces 11D intersect with the second upper surface 11C. The one or more outer surfaces 11D intersect with the lower surface 11B. The one or more inner surfaces 11E intersect with the second upper surface 11C.

[0030] When viewed from above, the outer edge shape of base 11 is rectangular. When viewed from above, the outer edge shape of base 11 is the outer edge shape of package 10. When viewed from above, the outer edge shape of first top surface 11A is rectangular. This rectangle can be a rectangle having long sides and short sides. The long side direction of first top surface 11A and the long side direction of the outer edge shape of base 11 are parallel. Note that when viewed from above, the outer edge shape of first top surface 11A does not have to be rectangular.

[0031] In a top view, first top surface 11A is surrounded by second top surface 11C. Second top surface 11C is an annular surface that surrounds first top surface 11A in a top view. Second top surface 11C is a rectangular annular surface. Here, the frame defined by the inner edge of second top surface 11C is referred to as the inner frame of second top surface 11C, and the frame defined by the outer edge of second top surface 11C is referred to as the outer frame of second top surface 11C.

[0032] The base 11 has a recess surrounded by a frame by the second upper surface 11C. The recess defines a portion of the base 11 that is recessed below the second upper surface 11C. The first upper surface 11A is a part of the recess. One or more inner surfaces 11E are also a part of the recess. The second upper surface 11C is located above the first upper surface 11A.

[0033] The base 11 has one or more step portions 11F. The step portion 11F has an upper surface 11G and a side surface 11H that intersects with the upper surface 11G and extends downward from the upper surface 11G. Here, one step portion 11F has only one upper surface 11G and one side surface 11H. The upper surface 11G intersects with the inner surface 11E. The side surface 11H intersects with the first upper surface 11A.

[0034] One or each step portion 11F is provided inside the inner frame of the second upper surface 11C in top view. One or each step portion 11F is formed along part or all of the inner surface 11E in top view. In the base 11, the side surface 11H is an inner surface, but the side surface 11H and the inner surface 11E are different surfaces. One or each inner surface 11E and one or each side surface 11H are perpendicular to the first upper surface 11A. Here, the perpendicular allows for a difference of ±3 degrees.

[0035] The one or more step portions 11F may include a first step portion 11F1 and a second step portion 11F2. The first step portion 11F1 and the second step portion 11F2 are provided at positions where their respective side surfaces 11H face each other. The first step portion 11F1 and the second step portion 11F2 are provided on the short side of the inner frame of the second upper surface 11C.

[0036] The base 11 has a base portion 11M and a frame portion 11N. The base portion 11M and the frame portion 11N may be made of different materials. The base 11 may be configured to include a base member corresponding to the base portion 11M and a frame member corresponding to the frame portion 11N.

[0037] Base portion 11M includes a first upper surface 11A. Frame portion 11N includes a second upper surface 11C. Frame portion 11N includes one or more outer surfaces 11D and one or more inner surfaces 11E. Frame portion 11N includes one or more step portions 11F.

[0038] The lower surface of base 11M constitutes part or all of the area of ​​lower surface 11B of base body 11. When the lower surface of base 11M constitutes part of the area of ​​lower surface 11B of base body 11, the lower surface of frame 11N constitutes the remaining area of ​​lower surface 11B of the base.

[0039] The base 11 has a plurality of wiring portions 12A. The plurality of wiring portions 12A includes one or more wiring portions 12A disposed in the internal space of the package 10 and one or more wiring portions 12A provided on the outer surface of the package 10.

[0040] One or each wiring portion 12A disposed in the internal space of package 10 is provided on the upper surface 11G of step portion 11F. Base 11 has one or more wiring portions 12A provided on the upper surface 11G of first step portion 11F1. Base 11 has one or more wiring portions 12A provided on the upper surface 11G of second step portion 11F2.

[0041] One or each of the wiring portions 12A provided on the outer surface of the package 10 is provided on the bottom surface 11B of the package 10. Each of these wiring portions 12A is provided on the bottom surface of the frame portion 11N. Note that some or all of these wiring portions 12A may be provided on an outer surface of the package 10 other than the bottom surface 11B.

[0042] In the base 11, one or each wiring portion 12A disposed in the internal space of the package 10 is electrically connected to a wiring portion 12A provided on the outer surface of the package 10.

[0043] The base 11 can be formed, for example, using ceramic as the main material. Examples of ceramic that can be the main material of the base 11 include aluminum nitride, silicon nitride, aluminum oxide, and silicon carbide.

[0044] Here, the term "main material" refers to the material that accounts for the largest proportion by mass or volume of the target structure. Note that when the target structure is formed from a single material, that material is the main material. In other words, when a material is the main material, it means that the proportion of that material can be 100%.

[0045] The base 11 may be formed using a base member and a frame member that are made of different main materials. The base member can be made of, for example, a material with excellent heat dissipation properties, such as a metal or a metal-containing composite, graphite, or diamond, as its main material. Examples of metals that can be used as the main material of the base member include copper, aluminum, and iron. Examples of metal-containing composites that can be used as the main material of the base member include copper-molybdenum and copper-tungsten. The frame member can be made of, for example, the ceramics listed above as the main material of the base 11.

[0046] The wiring portion 12A can be formed, for example, using a metal material as the main material. Examples of the metal material that is the main material of the wiring portion 12A include elemental metals such as Cu, Ag, Ni, Au, Ti, Pt, Pd, Cr, and W, and alloys containing these metals. The wiring portion 12A can be configured, for example, with one or more metal layers.

[0047] The lid 14 has an upper surface 14A and a lower surface 14B. The lid 14 also has one or more side surfaces 14C. The lid 14 is configured in the shape of a rectangular parallelepiped flat plate. However, the shape of the lid 14 does not have to be a rectangular parallelepiped.

[0048] The lid 14 is bonded to the base 11. The lower surface 14B of the lid 14 is bonded to the second upper surface 11C of the base 11. The lid 14 is bonded to the bonding pattern of the base 11. The lid 14 is bonded to the base 11 via an adhesive.

[0049] The lid body 14 has a translucent property that allows light to pass through. Here, translucency means that the transmittance of light incident on the lid body 14 is 80% or more. Note that the lid body 14 may have a non-translucent region (a region that does not have translucency) in part.

[0050] The lid 14 can be formed, for example, using glass as the main material, or can be formed, for example, using sapphire as the main material.

[0051] (semiconductor laser element 20) The semiconductor laser element 20 has an upper surface 21A, a lower surface 21B, and a plurality of side surfaces 21C. The shape of the upper surface 21A is a rectangle having long sides and short sides. The outer shape of the semiconductor laser element 20 when viewed from above is also a rectangle having long sides and short sides. However, the shape of the upper surface 21A and the outer shape of the semiconductor laser element 20 when viewed from above are not limited to this.

[0052] The semiconductor laser device 20 has a light emitting surface 22 that emits light. For example, the side surface 21C can serve as the light emitting surface 22. The side surface 21C that serves as the light emitting surface 22 intersects with a short side of the top surface 21A. Alternatively, for example, the top surface 21A can serve as the light emitting surface 22.

[0053] A single-emitter semiconductor laser element having one emitter can be used as the semiconductor laser element 20. Alternatively, a multi-emitter semiconductor laser element having multiple emitters can be used as the semiconductor laser element 20.

[0054] For example, a semiconductor laser element that emits blue light can be used as the semiconductor laser element 20. Alternatively, for example, a semiconductor laser element that emits green light can be used as the semiconductor laser element 20. Alternatively, for example, a semiconductor laser element that emits red light can be used as the semiconductor laser element 20. Note that a semiconductor laser element that emits light of another color or wavelength may also be used as the semiconductor laser element 20.

[0055] Here, blue light refers to light whose peak emission wavelength is in the range of 420 nm to 494 nm, green light refers to light whose peak emission wavelength is in the range of 495 nm to 570 nm, and red light refers to light whose peak emission wavelength is in the range of 605 nm to 750 nm.

[0056] The semiconductor laser element 20 that emits blue light or the semiconductor laser element 20 that emits green light may be a semiconductor laser element containing a nitride semiconductor. Examples of nitride semiconductors that can be used include GaN-based semiconductors such as GaN, InGaN, and AlGaN. The semiconductor laser element 20 that emits red light may be a semiconductor laser element containing InAlGaP-based, GaInP-based, or GaAs-based semiconductors such as GaAs and AlGaAs.

[0057] The semiconductor laser element 20 emits directional laser light. Diverging light with a spread is emitted from a light emitting surface 22 (emitting end surface) of the semiconductor laser element 20. 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 emitting surface 22. The FFP refers to the shape and light intensity distribution of the emitted light at a position away from the light emitting surface of the semiconductor laser element.

[0058] Here, the light passing through the center of the elliptical shape of the FFP, in other words, the light with 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 peak intensity value is 1 / e 2 The light having the above intensity is called the main part of the light.

[0059] The FFP of light emitted from the semiconductor laser element 20 has an elliptical shape in which the stacking direction is longer than the direction perpendicular to the stacking direction in a plane parallel to the light emitting surface 22. The stacking direction is the direction in which multiple semiconductor layers including the active layer are stacked in the semiconductor laser element 20. The direction perpendicular to the stacking direction can also be referred to as the in-plane direction of the semiconductor layers. The long axis direction of the elliptical shape of the FFP can also be referred to as the fast axis direction of the semiconductor laser element 20, and the short axis direction can also be referred to as the slow axis direction of the semiconductor laser element 20.

[0060] Based on the light intensity distribution of FFP, 1 / e of the peak light intensity 2 The angle at which light of this intensity spreads is defined as the light spread angle of the semiconductor laser element 20. Here, the light spread angle is the angle at which light of the peak intensity (light passing through the optical axis) spreads from the light of the peak intensity (light passing through the optical axis) to the light of the peak intensity (light passing through the optical axis) spreads from the light of the peak intensity (light passing through the optical axis) 2 The spread angle of light is expressed as the angle formed by the light of the peak light intensity. 2 In the explanation of this specification, when simply referring to the "angle of light", it is assumed that the angle is 1 / e of the peak light intensity. 2 This refers to the angle of spread of light at a light intensity of 1000 nm.

[0061] (Submount 30) The submount 30 has a top surface 31A, a bottom surface 31B, and one or more side surfaces 31C. The top surface 31A can be considered a mounting surface on which other components are mounted. The shape of the top surface 31A is rectangular. This rectangle of the top surface 31A may have short sides and long sides. However, the shape of the top surface 31A does not have to be rectangular.

[0062] The outer shape of the submount 30 when viewed from above is rectangular. This rectangle of the submount 30 may have short sides and long sides. However, the outer shape of the submount 30 when viewed from above does not have to be rectangular. When viewed from above, the submount 30 may have an outer shape in which the length in one direction (hereinafter, this direction will be referred to as the short-side direction of the submount 30) is shorter than the length in the direction perpendicular to this (hereinafter, this direction will be referred to as the long-side direction of the submount 30). In the illustrated submount 30, the short-side direction is the same as the X direction, and the long-side direction is the same as the Y direction.

[0063] For example, the length of the submount 30 in the short side or lateral direction is 500 μm or more and 1000 μm or less. Also, the length of the submount 30 in the long side or longitudinal direction is 1500 μm or more and 2500 μm or less. Also, the difference between the length of the submount 30 in the longitudinal direction and the length of the submount 30 in the lateral direction is 500 μm or more and 1000 μm or less.

[0064] (Reflective member 40) The reflecting member 40 has a lower surface 41A and a light-reflecting surface 41B that reflects light. The light-reflecting surface 41B is inclined with respect to the lower surface 41A. A line connecting the lower end and upper end of the light-reflecting surface 41B is inclined with respect to the lower surface 41A. The angle at which the light-reflecting surface 41B is inclined with respect to the lower surface 41A is referred to as the inclination angle of the light-reflecting surface 41B.

[0065] Light reflecting surface 41B is a flat surface. However, light reflecting surface 41B may be a curved surface. The inclination angle of light reflecting surface 41B is 45 degrees. However, the inclination angle of light reflecting surface 41B does not have to be 45 degrees.

[0066] The reflecting member 40 can be primarily made of glass, metal, or the like. It is preferable to use a heat-resistant material as the primary material of the reflecting member 40. The primary material can be, for example, glass such as quartz or BK7 (borosilicate glass), or metal such as Al. The reflecting member 40 can also be formed using Si as the primary material.

[0067] If the main material is a reflective material such as Al, the light reflecting surface 41B can be formed from the main material. Instead of forming the light reflecting surface 41B from the main material, the general shape of the reflecting member 40 may be formed from the main material, and the light reflecting surface 41B may be formed on the surface of the general shape. In this case, the light reflecting surface 41B can be formed using, for example, a metal layer such as Ag or Al, or a dielectric multilayer film such as Ta2O5 / SiO2, TiO2 / SiO2, or Nb2O5 / SiO2.

[0068] The light reflecting surface 41B has a reflectance of 90% or more for the peak wavelength of light irradiated onto the light reflecting surface 41B. This reflectance may also be 95% or more. This reflectance can also be 99% or more. The light reflectance is 100% or less or less than 100%.

[0069] (protective element 50) The protection element 50 has an upper surface 51A, a lower surface 51B, and one or more side surfaces 51C. The shape of the protection element 50 is a rectangular parallelepiped. However, the shape of the protection element 50 does not have to be a rectangular parallelepiped.

[0070] The protective element 50 is intended to prevent a specific element (such as a semiconductor laser element) from being destroyed by excessive current flowing through it. An example of the protective element 50 is a Zener diode. The Zener diode may be made of Si.

[0071] (Wiring 60) The wiring 60 is a linear conductive material with joints at both ends. The joints at both ends become joints with other components. The wiring 60 is used for electrical connection between two components. The wiring 60 is, for example, a metal wire. Examples of metals that can be used include gold, aluminum, silver, and copper.

[0072] (Optical member 70) The optical member 70 has an upper surface 71A, a lower surface 71B, and one or more side surfaces 71C. The optical member 70 imparts an optical effect to light incident on the optical member 70. Examples of the optical effect imparted to light by the optical member 70 include light collection, collimation, diffusion, polarization, diffraction, wave combination, light guidance, reflection, and wavelength conversion.

[0073] The optical member 70 has an optically active surface that provides an optical effect. The upper surface 71A, the lower surface 71B, or the side surface 71C can be the optically active surface. Alternatively, the optically active surface may be located at a position different from the upper surface 71A, the lower surface 71B, or the side surface 71C. For example, the optically active surface may be formed inside the optical member 70 rather than on the surface thereof.

[0074] The optical element 70 may have one or more lens surfaces 71D. The lens surfaces 71D are optically active surfaces of the optical element 70. Note that the optical element 70 having the lens surfaces 71D may also be called a lens element. The optical element 70 provides optical effects such as focusing, diffusing, or collimating to light that passes through the lens surfaces 71D and is emitted from the optical element 70. For example, the optical element 70 is a collimating lens that collimates light that is incident on the optical element 70 and emits it.

[0075] One or each lens surface 71D is provided on the upper surface 71A side. Alternatively, lens surface 71D may be provided on the lower surface 71B side. Upper surface 71A and lower surface 71B are flat surfaces. One or each lens surface 71D intersects with upper surface 71A. In a top view, one or each lens surface 71D is surrounded by upper surface 71A.

[0076] When viewed from above, the outer shape of the optical member 70 is rectangular. However, the outer shape of the optical member 70 when viewed from above does not have to be rectangular. The lower surface 71B is flat. No lens surface 71D is formed on the lower surface 71B side of the optical member 70. The shape of the lower surface 71B is rectangular. However, the shape of the lower surface 71B does not have to be rectangular.

[0077] In optical member 70, the portion overlapping with lens surface 71D in top view is referred to as lens portion 72A. In optical member 70, the portion overlapping with top surface 71A in top view is referred to as non-lens portion 72B. Bottom surface 71B has an area that forms the bottom surface of one or each lens portion 72A, and an area that forms the bottom surface of non-lens portion 72B.

[0078] The optical member 70 may have a plurality of lens surfaces 71D formed in a line. The direction in which the plurality of lens surfaces 71D are arranged in a top view is referred to as the lens connection direction. In the illustrated optical member 70, the connection direction is the same as the X direction.

[0079] The plurality of lens surfaces 71D are formed so that the vertices of the respective lens surfaces 71D are aligned on a straight line. This imaginary line connecting the vertices is parallel to the lower surface 71B of the optical member 70. Note that "parallel" here includes a difference of ±5 degrees or less.

[0080] The curvature of two or more lens surfaces 71D may be the same for some or all of the lens surfaces 71D. All of the lens surfaces 71D may have the same curvature.

[0081] The optical member 70 is translucent. The optical member 70 has a transmittance of 80% or more for the peak wavelength of light incident on the optical member 70. The optical member 70 may have a translucent region and a non-translucent region (hereinafter referred to as a non-translucent region). In the non-translucent region, the transmittance for the peak wavelength of light incident on the optical member 70 is 50% or less. The optical member 70 can be formed using glass such as BK7, for example.

[0082] Next, the light emitting device will be described.

[0083] (Light-emitting device 1) In the light emitting device 1, one or more semiconductor laser elements 20 are arranged in the internal space of the package 10. The one or more semiconductor laser elements 20 are arranged on the first upper surface 11A. The one or more semiconductor laser elements 20 are arranged on the first upper surface 11A via one or more submounts 30.

[0084] The one or more semiconductor laser elements 20 may be configured with a plurality of semiconductor laser elements 20 including a first semiconductor laser element 20A and a second semiconductor laser element 20B. The plurality of semiconductor laser elements 20 may further include one or more third semiconductor laser elements 20C.

[0085] The second semiconductor laser element 20B has a longer length in the cavity direction than the first semiconductor laser element 20A. The cavity direction is a direction perpendicular to the light emitting surface 22. In the example of the light emitting device 1 shown in the figure, the cavity direction is the same as the Y direction.

[0086] The length of the first semiconductor laser element 20A in the cavity direction can be 500 μm or more and 1500 μm or less. The length of the second semiconductor laser element 20B in the cavity direction is greater than the length of the first semiconductor laser element 20A in the cavity direction by 200 μm or more and 1500 μm or less.

[0087] The plurality of semiconductor laser elements 20 can be arranged side by side in one direction. The plurality of semiconductor laser elements 20 can be arranged side by side in the long side direction of the package 10. The resonator direction of each semiconductor laser element 20 can be in the same direction as the short side direction of the package 10. This allows a greater number of semiconductor laser elements 20 to be arranged side by side in the package 10.

[0088] The one or more inner surfaces 11E include a first inner surface 11E1 and a second inner surface 11E2 that face each other. The multiple semiconductor laser elements 20 are arranged in one direction between the first inner surface 11E1 and the second inner surface 11E2 in a top view. The direction in which the first inner surface 11E1 and the second inner surface 11E2 face each other is the same direction in which the multiple semiconductor laser elements 20 are lined up.

[0089] The first semiconductor laser element 20A is disposed closer to the first inner side surface 11E1 than the second semiconductor laser element 20B. The distance from the first semiconductor laser element 20A to the first inner side surface 11E1 is shorter than the distance from the second semiconductor laser element 20B to the first inner side surface 11E1.

[0090] The second semiconductor laser element 20B is disposed at a position closer to the first inner side surface 11E1 than the third semiconductor laser element 20C. The second semiconductor laser element 20B is disposed at a position spaced apart from the first semiconductor laser element 20A in a predetermined direction, and one or more third semiconductor laser elements 20C are disposed at positions spaced apart from the second semiconductor laser element 20B in the same direction.

[0091] One or more semiconductor laser elements 20 emit light laterally from their light emitting surfaces 22. The multiple semiconductor laser elements 20 emit light in the same direction. The multiple semiconductor laser elements 20 are arranged such that their respective light emitting surfaces 22 face the same direction. In the example of the light emitting device 1 shown in the figure, all of the semiconductor laser elements 20 emit light in the positive Y direction.

[0092] There is a difference of 50 nm or more between the peak emission wavelength of the light emitted from the first semiconductor laser element 20A and the peak emission wavelength of the light emitted from 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.

[0093] The first, second, and third semiconductor laser elements 20A, 20B, and 20C emit light of different colors, red, green, and blue, respectively. These three semiconductor laser elements 20 emit red, green, and blue light.

[0094] The first semiconductor laser element 20A has a higher wall plug efficiency (WPE) than the second semiconductor laser element 20B. For example, the first semiconductor laser element 20A emits blue light, and the second semiconductor laser element 20B emits green light.

[0095] In a top view, the width of the first semiconductor laser element 20A and the width of the second semiconductor laser element 20B are the same in the direction perpendicular to the cavity direction. Note that "same" here includes a difference of 30 μm or less.

[0096] In the light emitting device 1, one or more submounts 30 are disposed in the internal space of the package 10. The one or more submounts 30 are disposed on the first upper surface 11A. One or more semiconductor laser elements 20 are disposed on the upper surface 31A of one or each submount 30.

[0097] The one or more submounts 30 may be configured with a plurality of submounts 30 including a first submount 30A and a second submount 30B. The plurality of submounts 30 may further include one or more third submounts 30C.

[0098] The first semiconductor laser element 20A is disposed on the first submount 30A, the second semiconductor laser element 20B is disposed on the second submount 30B, and the third semiconductor laser element 20C is disposed on the third submount 30C.

[0099] When viewed from above, the longitudinal length of the first submount 30A and the longitudinal length of the second submount 30B are the same. Note that "same" here includes a difference of up to 100 μm. Also, when viewed from above, the lateral length of the first submount 30A and the lateral length of the second submount 30B are the same. Note that "same" here includes a difference of up to 100 μm.

[0100] The first semiconductor laser element 20A is placed on the first submount 30A with the long side of the top surface 21A of the first semiconductor laser element 20A aligned with the longitudinal direction of the first submount 30A. The cavity direction of the first semiconductor laser element 20A can be the same as the longitudinal direction of the first submount 30A. Note that "same" here includes a difference of ±3 degrees or less.

[0101] The second semiconductor laser element 20B is placed on the second submount 30B with the long side of the top surface 21A of the second semiconductor laser element 20B aligned with the longitudinal direction of the second submount 30B. The cavity direction of the second semiconductor laser element 20B can be the same as the longitudinal direction of the first submount 30A. Note that "same" here includes a difference of ±3 degrees or less.

[0102] In the light emitting device 1, two semiconductor laser elements 20 having different lengths in the cavity direction are disposed on two submounts 30 having the same length in the longitudinal direction.

[0103] In the light emitting device 1, one or more reflecting members 40 are disposed in the internal space of the package 10. The one or more reflecting members 40 are disposed on the first upper surface 11A. The one or more reflecting members 40 reflect light emitted from the one or more semiconductor laser elements 20.

[0104] The light reflecting surface 41B of the or each reflecting member 40 faces the light emitting surface 22 of the semiconductor laser element 20. Light emitted from the semiconductor laser element 20 and traveling along the optical axis is reflected by the light reflecting surface 41B and travels upward perpendicular to the optical axis.

[0105] In the light emitting device 1, one or more protection elements 50 are disposed in the internal space of the package 10. The one or more protection elements 50 protect one or more semiconductor laser elements 20.

[0106] The one or more protection elements 50 may be configured with a plurality of protection elements 50 including a first protection element 50A and a second protection element 50B. The plurality of protection elements 50 may further include a third protection element 50C.

[0107] The first protection element 50A protects the first semiconductor laser element 20A. The second protection element 50B protects the second semiconductor laser element 20B. The third protection element 50C protects one or more third semiconductor laser elements 20C.

[0108] The first protection element 50A is disposed on the first submount 30A. The second protection element 50B is disposed on the second submount 30B. The third protection element 50C is not disposed on the submount 30. The third protection element 50C is disposed on the wiring portion 12A.

[0109] The first protection element 50A is disposed at a position closer to the first inner side surface 11E1 than the first semiconductor laser element 20A. The second protection element 50B is disposed at a position closer to the first inner side surface 11E1 than the second semiconductor laser element 20B.

[0110] Here, in the semiconductor laser element 20, the surface located opposite to the light emitting surface 22 is referred to as the first surface 23. When a certain side surface 31C of the semiconductor laser element 20 is the light emitting surface 22, the side surface 31C located opposite to the light emitting surface 22 becomes the first surface 23. Furthermore, the direction proceeding from the first surface 23 to the light emitting surface 22 of the semiconductor laser element 20 is referred to as the first direction.

[0111] The first protection element 50A is disposed at a position close to the first surface 23 of the first semiconductor laser element 20A. In a top view, the distance from the first protection element 50A to the first surface 23 of the first semiconductor laser element 20A is shorter than the distance from the first protection element 50A to the light emission surface 22 of the first semiconductor laser element 20A. The first surface 23 of the first semiconductor laser element 20A is disposed at a position farther away in the first direction than the first protection element 50A.

[0112] The second protection element 50B is disposed at a position close to the first surface 23 of the second semiconductor laser element 20B. In a top view, the distance from the second protection element 50B to the first surface 23 of the second semiconductor laser element 20B is shorter than the distance from the second protection element 50B to the light emission surface 22 of the second semiconductor laser element 20B.

[0113] In a top view, the distance from the light emitting surface 22 of the first semiconductor laser element 20A to the first protective element 50A is the same as the distance from the light emitting surface 22 of the second semiconductor laser element 20B to the second protective element 50B. Note that "same" here includes a difference of 100 μm or less.

[0114] The relative position at which the first protection element 50A is arranged on the upper surface 31A of the first submount 30A is the same as the relative position at which the second protection element 50B is arranged on the upper surface 31A of the second submount 30B.

[0115] The first protective element 50A and the second protective element 50B are protective elements 50 of the same size. The third protective element 50C is a protective element 50 larger in size than the first protective element 50A. The third protective element 50C is a protective element 50 larger in size than the second protective element 50B. The size of the upper surface 51A of the third protective element 50C is such that the third protective element 50C cannot be placed without coming into contact with the third semiconductor laser element 20C and without protruding from the upper surface 31A of the third submount 30C in top view.

[0116] In the light emitting device 1, the plurality of wirings 60 are electrically connected to one or more semiconductor laser elements 20. The plurality of wirings 60 are also electrically connected to one or more protection elements .

[0117] In the light emitting device 1, one or more semiconductor laser elements 20 are electrically connected to the package 10 by a plurality of wirings 60. Furthermore, one or more protection elements 50 are electrically connected to the package 10 by a plurality of wirings 60.

[0118] The multiple wirings 60 include a first wiring 60A that is bonded to the first protection element 50A. The first wiring 60A is not bonded to the first semiconductor laser element 20A. The first wiring 60A is not bonded to the first submount 30A. The first wiring 60A is bonded to the wiring portion 12A.

[0119] The plurality of wirings 60 includes a second wiring 60B joined to the second protection element 50B. The second wiring 60B is joined to the upper surface 21A of the second semiconductor laser element 20B.

[0120] By utilizing the fact that the second semiconductor laser element 20B is longer in the cavity direction than the first semiconductor laser element 20A, one end of the second wiring 60B, which is joined to the second protection element 50B, is joined to the upper surface 21A of the second semiconductor laser element 20B, thereby making it possible to reduce the length of the second wiring 60B and the wiring resistance.

[0121] It is not essential that the second semiconductor laser element 20B be longer in the cavity direction than the first semiconductor laser element 20A. As is clear from Fig. 6A and other figures, even if the length of the first semiconductor laser element 20A in the cavity direction is the same as the length of the second semiconductor laser element 20B in the cavity direction, the top surface 21A of the second semiconductor laser element 20B can be used for bonding the second wiring 60B.

[0122] 6A to 6C, the second wiring 60B is arranged so as not to pass through the imaginary straight line L1 in top view. Here, the imaginary straight line L1 is a straight line that passes through and is parallel to the first surface 23 of the first semiconductor laser element 20A in top view.

[0123] The plurality of wirings 60 includes a third wiring 60C bonded to the upper surface 21A of the first semiconductor laser element 20A. The plurality of wirings 60 may include a plurality of third wirings 60C. None of the plurality of third wirings 60C is bonded to the protection element 50. By arranging the first semiconductor laser element 20A at a position farther away from the first protection element 50A in the first direction, it becomes easier to bond the first wiring 60A and the third wiring 60C.

[0124] The plurality of wirings 60 includes a fourth wiring 60D bonded to the upper surface 21A of the second semiconductor laser element 20B. The plurality of wirings 60 includes a plurality of fourth wirings 60D. None of the plurality of fourth wirings 60D is bonded to the protection element 50. Note that the plurality of fourth wirings 60D are wirings 60 that do not include the second wirings 60B.

[0125] When the upper surface 21A of the second semiconductor laser element 20B is divided into two regions by a virtual straight line L1 in a top view, one or more fourth wirings 60D are joined to one region, and the second wiring 60B is joined to the other region. The fourth wirings 60D are joined to the upper surface 21A of the second semiconductor laser element 20B at a position spaced apart from the second wirings 60B in the first direction.

[0126] In this way, the light emitting device 1 includes a first semiconductor laser element 20A in which no wirings other than the plurality of third wirings 60C are bonded to the top surface 21A, and a second semiconductor laser element 20B in which the second wirings 60B as well as the plurality of fourth wirings 60D are bonded to the top surface 21A, depending on the difference in the length of the top surface 21A in the cavity direction. Note that no wirings other than the second wirings 60B and the plurality of fourth wirings 60D are bonded to the top surface 21A of the second semiconductor laser element 20B.

[0127] The wiring 60 joined to the first protection element 50A is only the first wiring 60A. The wiring 60 joined to the second protection element 50B is only the second wiring 60B. The first wiring 60A is longer than the second wiring 60B. The number of the multiple third wirings 60C is the same as the number of the multiple fourth wirings 60D. The third wiring 60C is shorter than the fourth wiring 60D. By making the number of the third wirings 60C and the number of the fourth wirings 60D the same, the difference in electrical load on each wiring 60 can be reduced, contributing to stable wiring connection.

[0128] The multiple fourth wirings 60D are bonded to the second semiconductor laser element 20B at positions closer to the light emitting surface 22 than the second wirings 60B. As shown in FIGS. 6A to 6C, the distance from position P1 at which the fourth wirings 60D are bonded to the upper surface 21A of the second semiconductor laser element 20B to the light emitting surface 22 of the second semiconductor laser element 20B is shorter than the distance from position P2 at which the second wirings 60B are bonded to the upper surface 21A of the second semiconductor laser element 20B to the light emitting surface 22 of the second semiconductor laser element 20B. This relationship is not limited to the fourth wirings 60D indicated by the arrow P1 in FIG. 6A, but also holds true for the fourth wirings 60D that are farthest from the light emitting surface 22.

[0129] In the cavity direction, the distance from the light emitting surface 22 of the first semiconductor laser element 20A to the third wiring 60C that is closest to this light emitting surface 22 is shorter than the distance from the light emitting surface 22 of the second semiconductor laser element 20B to the fourth wiring 60D that is closest to this light emitting surface 22. This allows the multiple wirings 60 to be joined in a balanced manner according to their lengths in the cavity direction, thereby improving the quality of the semiconductor laser element 20.

[0130] The package 10 has a plurality of wiring portions 12A, each of which is connected to one or more of the plurality of wiring portions 60. The plurality of wiring portions 12A includes a first wiring portion 12A1 and a second wiring portion 12A2. The plurality of wiring portions 12A also includes a third wiring portion 12A3 and a fourth wiring portion 12A4.

[0131] The first wiring 60A is joined to the first wiring portion 12A1. The third wiring 60C is joined to the first wiring portion 12A1. A plurality of the third wirings 60C are joined to the first wiring portion 12A1. The fourth wiring 60D is joined to the second wiring portion 12A2. A plurality of the fourth wirings 60D are joined to the second wiring portion 12A2.

[0132] The plurality of wirings 60 include one or more fifth wirings 60E joined to the third wiring portion 12A3 and one or more sixth wirings 60F joined to the fourth wiring portion 12A4. The one or more fifth wirings 60E are joined to the third semiconductor laser element 20C. The one or more sixth wirings 60F are joined to the third submount 30C.

[0133] The first wiring portion 12A1 and the second wiring portion 12A2 are provided on the first inner side surface 11E1 side. Therefore, the distance from the first semiconductor laser element 20A to the first wiring portion 12A1 is shorter than the distance from the second semiconductor laser element 20B to the first wiring portion 12A1.

[0134] The first wiring portion 12A1 and the second wiring portion 12A2 are arranged side by side in the resonator direction. The first wiring portion 12A1 is provided at a position spaced apart from the second wiring portion 12A2 in the first direction. The first wiring portion 12A1 and the second wiring portion 12A2 are provided on the upper surface 11G of the first step portion 11F1. The sum of the lengths of the first wiring portion 12A1 and the second wiring portion 12A2 in the resonator direction is greater than the length of the first submount 30A.

[0135] The third wiring portion 12A3 and the fourth wiring portion 12A4 are provided on the second inner side surface 11E2 side. The third wiring portion 12A3 and the fourth wiring portion 12A4 are arranged side by side in the resonator direction. The third wiring portion 12A3 is provided at a position spaced apart from the fourth wiring portion 12A4 in the first direction. The third wiring portion 12A3 and the fourth wiring portion 12A4 are provided on the upper surface 11G of the second step portion 11F2.

[0136] 6A to 6C, if the position where the fourth wiring 60D is joined to the second wiring portion 12A2 is designated as position P3, position P1 is located closer to the first direction than the first protective element 50A, and position P3 is located closer to the direction opposite to the first direction than the first protective element 50A. Because the second wiring 60B is joined to the second semiconductor laser element 20B, even if the fourth wiring 60D is provided in this manner, the second wiring 60B and the fourth wiring 60D do not overlap in top view, and contact between the wirings can be easily avoided.

[0137] In the light emitting device 1, if the position where the first wiring 60A is joined to the first wiring portion 12A1 is designated as position P4, then position P4 is located closer to the first direction than position P3. Also, position P4 is located in the direction opposite to the first direction than position P1. In the light emitting device 1, if the position where the third wiring 60C is joined to the first wiring portion 12A1 is designated as position P5, then position P5 is located closer to the first direction than position P4.

[0138] In top view, the third wiring 60C and the fourth wiring 60D do not overlap. The multiple fourth wirings 60D include one or more fourth wirings 60D that pass through the first submount 30A in top view. Note that "passing through" here does not include the case where one end of the fourth wiring 60D overlaps with the first submount 30A in top view. In other words, both ends of the fourth wiring 60D are located outside the first submount 30A in top view.

[0139] When viewed from above, the one or more fourth wirings 60D are joined to the upper surface 21A of the second semiconductor laser element 20B and the second wiring portion 12A2 so that a virtual straight line L2 passing through the second protection element 50B and extending in a second direction perpendicular to the first direction passes through the same.

[0140] In top view, multiple fourth wirings 60D pass between the position where the first wiring 60A is bonded to the first protection element 50A and the position where the second wiring 60B is bonded to the second protection element 50B. Position P3 is located on the side opposite to the first direction from the first submount 30A. Position P3 is located on the side opposite to the first direction from the second submount 30B.

[0141] In this way, by using a number of wirings 60 and arranging the wirings 60 so as not to interfere with other wirings 60, it is possible to arrange a plurality of semiconductor laser elements 20 closely and achieve stable wiring connections.

[0142] The multiple wirings 60 include multiple seventh wirings 60G that electrically connect two adjacent submounts 30. The multiple seventh wirings 60G include a seventh wiring 60G that electrically connects the first submount 30A and the second submount 30B that are arranged adjacent to each other, and a seventh wiring 60G that electrically connects the second submount 30B and the third submount 30C that are arranged adjacent to each other.

[0143] In the light emitting device 1, the optical member 70 is bonded to the package 10. A lower surface 71B of the optical member 70 faces an upper surface 14A of the package 10. The optical member 70 and the package 10 are bonded together via an adhesive.

[0144] The light reflected by the reflecting member 40 is emitted from the upper surface 14A of the package 10 and is incident on the optical member 70. The light incident on the optical member 70 is subjected to an optical action by the optical action surface and is emitted from the optical member 70. For example, collimated light is emitted from the light emitting device 1.

[0145] Second Embodiment A light emitting device 2 according to a second embodiment will be described. FIGS. 1 to 4 and 7 to 13 are drawings for explaining an exemplary embodiment of the light emitting device 2. FIG. 1 is a perspective view of the light emitting device 2. FIG. 2 is a side view of the light emitting device 2. FIG. 3 is a top view of the light emitting device 2. FIG. 4 is a cross-sectional view of the light emitting device 2 taken along line IV-IV in FIG. 3. FIG. 7 is a cross-sectional view of a package 10 of the light emitting device 2. The cross-sectional view in FIG. 7 corresponds to the cross-section taken along line IV-IV in FIG. 3. FIG. 8 is a top view of a base 11 of the light emitting device 2. FIG. 9 is a bottom view of the base 11. FIG. 10 is a cross-sectional view of the base 11. The cross-sectional view in FIG. 10 corresponds to the cross-section taken along line IV-IV in FIG. 3. FIG. 11 is a schematic diagram of a semiconductor laser element 20 and a protective element 50 arranged on a submount 30. FIG. 12 is a top view showing the internal structure of the light emitting device 2. FIG. 13 is an enlarged view for explaining the wiring connection mode of the light emitting device 2.

[0146] Of the above-mentioned descriptions of the light emitting device 1 and each component of the first embodiment, all contents except for those that may be considered to be inconsistent with the drawings of the light emitting device 2 in Figures 1 to 4 and 7 to 13 also apply to the description of the light emitting device 2. To avoid redundancy, all non-inconsistent contents will not be repeated here.

[0147] (Light-emitting device 2) The light emitting device 2 differs from the light emitting device 1 in that the orientation of the electrodes of the semiconductor laser element 20 is reversed. In the light emitting device 1, if a first electrode is provided on the upper surface 21A of the semiconductor laser element 20 and a second electrode is provided on the lower surface 21B, then in the light emitting device 2, a second electrode is provided on the upper surface 21A of the semiconductor laser element 20 and a first electrode is provided on the lower surface 21B. In this way, even if the orientation of the pn junction in the semiconductor laser element 20 is reversed, a light emitting device can be realized.

[0148] In the light emitting device 2, the first wiring 60A is bonded to the upper surface 21A of the second semiconductor laser element 20B. The position where the first wiring 60A is bonded to the upper surface 21A of the second semiconductor laser element 20B is located on the first direction side of the position where the second wiring 60B is bonded to the upper surface 21A of the second semiconductor laser element 20B. The first wiring 60A is arranged so as not to pass through the imaginary line L1 in a top view.

[0149] In the light emitting device 2, one or more third wirings 60C are bonded to the upper surface 21A of the second semiconductor laser element 20B. When the upper surface 21A of the second semiconductor laser element 20B is divided into two regions by an imaginary straight line L1 in a top view, one or more third wirings 60C are bonded to one region, and the first wiring 60A is bonded to the other region.

[0150] In the light emitting device 2, the wiring 60 bonded to the first wiring portion 12A1 is bonded to the first submount 30A. The wiring 60 bonded to the second wiring portion 12A2 is bonded to the second submount 30B. One or more fourth wirings 60D are bonded to the top surface 21A of the third semiconductor laser element 20C.

[0151] In the light emitting device 2, the first wiring 60A or the third wiring 60C electrically connects the adjacent first submount 30A and second submount 30B, and the fourth wiring 60D electrically connects the adjacent second submount 30B and third submount 30C.

[0152] Although the above describes various embodiments of the present invention, the light-emitting device according to the present invention is not strictly limited to the light-emitting device of each embodiment. In other words, the present invention can be realized without being limited to the external shape and structure of the light-emitting device disclosed in each embodiment. The present invention can be applied without necessarily including all components. For example, if the claims do not recite some of the components of the light-emitting device disclosed in the embodiments, the claims allow for the design freedom of those components by those skilled in the art, such as substitution, omission, modification of shape, and change of material, and specify that the invention described in the claims is applicable.

[0153] Through the contents described so far in this specification, the following technical matters are disclosed. (Section 1) a plurality of semiconductor laser elements including a first semiconductor laser element and a second semiconductor laser element, each having a top surface and a light emitting surface; a plurality of protection elements including a first protection element for protecting the first semiconductor laser element and a second protection element for protecting the second semiconductor laser element; a plurality of wirings including a first wiring joined to the first protection element and a second wiring joined to the second protection element, the wirings being electrically connected to the plurality of semiconductor laser elements and the plurality of protection elements; the first wiring is not joined to the first semiconductor laser element, the second wiring is bonded to the top surface of the second semiconductor laser element. (Section 2) Item 2. The light emitting device according to item 1, wherein the second semiconductor laser element has a length in the cavity direction greater than that of the first semiconductor laser element. (Section 3) Item 3. The light emitting device according to item 1 or 2, wherein the plurality of wirings include a plurality of third wirings joined to the upper surface of the first semiconductor laser element and a plurality of fourth wirings joined to the upper surface of the second semiconductor laser element. (Section 4) Item 4. The light emitting device according to item 3, wherein the number of the plurality of third wirings is the same as the number of the plurality of fourth wirings. (Section 5) Item 5. The light emitting device according to item 3 or 4, wherein a distance from a position where the fourth wiring is bonded to the top surface of the second semiconductor laser element to the light emitting surface of the second semiconductor laser element is shorter than a distance from a position where the second wiring is bonded to the top surface of the second semiconductor laser element to the light emitting surface of the second semiconductor laser element. (Section 6) each of the plurality of semiconductor laser elements has a first surface located opposite the light emitting surface; a distance from the first protection element to the first surface of the first semiconductor laser element is shorter than a distance from the first protection element to the light emission surface of the first semiconductor laser element, when viewed from above; 6. The light emitting device according to any one of items 1 to 5, wherein, in a top view, a distance from the second protection element to the first surface of the second semiconductor laser element is shorter than a distance from the second protection element to the light emitting surface of the second semiconductor laser element. (Section 7) 7. The light emitting device according to item 6, wherein, in a top view, the distance from the light emitting surface of the first semiconductor laser element to the first protective element is the same as the distance from the light emitting surface of the second semiconductor laser element to the second protective element. (Section 8) each of the packages has a plurality of wiring portions to which one or more of the plurality of wirings are joined; the plurality of wiring portions include a first wiring portion and a second wiring portion; the first wiring is joined to the first wiring portion, 8. The light emitting device according to any one of items 1 to 7, wherein the distance from the first semiconductor laser element to the first wiring portion is shorter than the distance from the second semiconductor laser element to the first wiring portion. (Section 9) the plurality of wirings include a third wiring joined to the top surface of the first semiconductor laser element and a fourth wiring joined to the top surface of the second semiconductor laser element; the third wiring is joined to the first wiring portion, Item 9. The light emitting device according to item 8, wherein the fourth wiring is joined to the second wiring portion. (Section 10) a first position where the fourth wiring is bonded to the top surface of the second semiconductor laser element is located on a first direction side of the first protection element; a second position where the fourth wiring is joined to the second wiring portion is located on a side opposite to the first direction from the first protection element; a third position where the first wiring is joined to the first wiring portion is located closer to the first direction than the second position; 10. The light emitting device according to item 9, wherein a fourth position where the third wiring is joined to the first wiring portion is located on the first direction side of the third position. (Section 11) a plurality of submounts including a first submount on which the first semiconductor laser element and the first protection element are disposed, and a second submount on which the second semiconductor laser element and the second protection element are disposed, Item 11. The light emitting device according to item 10, wherein the fourth wiring passes through the first submount in top view. (Section 12) Item 12. The light-emitting device according to item 11, wherein, in a top view, the fourth wiring is joined to the top surface of the second semiconductor laser element and the second wiring portion so that a virtual straight line passing through the second protection element and extending in a second direction perpendicular to the first direction passes through the fourth wiring. (Section 13) The package has a first inner surface and a second inner surface opposite the first inner surface, the plurality of semiconductor laser elements are arranged side by side in the second direction between the first inner side surface and the second inner side surface in a top view, the plurality of wiring portions further include a third wiring portion and a fourth wiring portion; the first wiring portion and the second wiring portion are provided on the first inner surface side of the package, the third wiring portion and the fourth wiring portion are provided on the second inner surface side of the package, the plurality of semiconductor laser elements include one or more third semiconductor laser elements, the second semiconductor laser element is disposed at a position spaced apart from the first semiconductor laser element in the second direction, the one or more third semiconductor laser elements are disposed at positions spaced apart from the second semiconductor laser element in the second direction, Item 13. The light emitting device according to item 12, wherein the plurality of wirings include one or more fifth wirings joined to the third wiring portion and one or more sixth wirings joined to the fourth wiring portion. [Industrial Applicability]

[0154] The light-emitting device described in the embodiment can be used in a projector. In other words, a projector can be considered one application form to which the present invention can be applied. However, the present invention is not limited to this application form and can be used in various applications such as illumination, exposure, in-vehicle headlights, head-mounted displays, and backlights for other displays. [Explanation of symbols]

[0155] 1. Light-emitting device 10 packages 11 Base 11A 1st top surface 11B Bottom side 11C 2nd top surface 11D External surface 11E Inside surface 11E1 1st inner surface 11E2 2nd inner surface 11F step 11F1 First step 11F2 Second step 11G top surface 11H side 11M Base 11N frame 12A wiring section 12A1 1st wiring section 12A2 2nd wiring section 12A3 3rd wiring section 12A4 4th wiring section 14 Lid 14A Top 14B Bottom 14C side 20 Semiconductor laser element 20A First semiconductor laser element 20B Second semiconductor laser element 20C Third semiconductor laser element 21A Top 21B Bottom surface 21C side 22 Light exit surface 23 Page 1 30 Submount 30A 1st submount 30B Second submount 30C 3rd submount 31A Top 31B Bottom surface 31C side 40 Reflective material 41A Bottom 41B Light reflective surface 50 Protection element 50A First Protection Element 50B Second protection element 50C Third protection element 51A Top 51B Bottom side 51C side 60 Wiring 60A 1st wire 60B 2nd wiring 60C 3rd wiring 60D 4th wiring 60E 5th wiring 60F 6th wiring 60G 7th wiring 70 Optical components (lens components) 71A Top 71B Bottom side 71C side 71D Lens surface (optical surface) 72A Lens section 72B Non-lens part

Claims

1. a plurality of semiconductor laser elements including a first semiconductor laser element and a second semiconductor laser element, each having a top surface and a light emitting surface; a plurality of protection elements including a first protection element for protecting the first semiconductor laser element and a second protection element for protecting the second semiconductor laser element; a plurality of wirings including a first wiring joined to the first protection element and a second wiring joined to the second protection element, the wirings being electrically connected to the plurality of semiconductor laser elements and the plurality of protection elements; the first wiring is not joined to the first semiconductor laser element, the second wiring is bonded to the top surface of the second semiconductor laser element.

2. The light emitting device according to claim 1 , wherein the second semiconductor laser element has a length in the cavity direction greater than that of the first semiconductor laser element.

3. 2. The light emitting device according to claim 1, wherein the plurality of wirings include a plurality of third wirings joined to the upper surface of the first semiconductor laser element and a plurality of fourth wirings joined to the upper surface of the second semiconductor laser element.

4. The light emitting device according to claim 3 , wherein the number of the third wirings is the same as the number of the fourth wirings.

5. 5. The light emitting device according to claim 4, wherein a distance from a position (P1) where the fourth wiring is joined to the upper surface of the second semiconductor laser element to the light emitting surface of the second semiconductor laser element is shorter than a distance from a position (P2) where the second wiring is joined to the upper surface of the second semiconductor laser element to the light emitting surface of the second semiconductor laser element.

6. each of the plurality of semiconductor laser elements has a first surface located opposite the light emitting surface; a distance from the first protection element to the first surface of the first semiconductor laser element is shorter than a distance from the first protection element to the light emission surface of the first semiconductor laser element, when viewed from above; 2. The light emitting device according to claim 1, wherein, in a top view, a distance from the second protection element to the first surface of the second semiconductor laser element is shorter than a distance from the second protection element to the light emission surface of the second semiconductor laser element.

7. 7. The light emitting device according to claim 6, wherein, in a top view, a distance from the light emitting surface of the first semiconductor laser element to the first protective element is the same as a distance from the light emitting surface of the second semiconductor laser element to the second protective element.

8. a package in which the plurality of semiconductor laser elements are arranged, the package has a plurality of wiring portions to which one or more of the plurality of wirings are joined, the plurality of wiring portions include a first wiring portion and a second wiring portion, the first wiring is joined to the first wiring portion, 2. The light emitting device according to claim 1, wherein the distance from said first semiconductor laser element to said first wiring portion is shorter than the distance from said second semiconductor laser element to said first wiring portion.

9. the plurality of interconnects include a third interconnect bonded to the top surface of the first semiconductor laser element and a fourth interconnect bonded to the top surface of the second semiconductor laser element; the third wiring is joined to the first wiring portion, The light emitting device according to claim 8 , wherein the fourth wiring is joined to the second wiring portion.

10. a first position (P1) at which the fourth wiring is bonded to the top surface of the second semiconductor laser element is located on a first direction side of the first protection element; a second position (P3) at which the fourth wiring is joined to the second wiring portion is located on a side opposite to the first direction from the first protection element; a third position (P4) at which the first wiring is joined to the first wiring portion is located closer to the first direction than the second position; The light emitting device according to claim 9 , wherein a fourth position (P5) at which the third wiring is joined to the first wiring portion is located closer to the first direction than the third position.

11. a plurality of submounts including a first submount on which the first semiconductor laser element and the first protection element are disposed, and a second submount on which the second semiconductor laser element and the second protection element are disposed, The light emitting device according to claim 10 , wherein the fourth wiring passes through the first submount in a top view.

12. 12. The light emitting device of claim 11, wherein, in a top view, the fourth wiring is joined to the top surface of the second semiconductor laser element and the second wiring portion so that a virtual straight line passing through the second protection element and extending in a second direction perpendicular to the first direction passes through the fourth wiring.

13. The package has a first inner surface and a second inner surface opposite the first inner surface, the plurality of semiconductor laser elements are arranged side by side in the second direction between the first inner side surface and the second inner side surface in a top view, the plurality of wiring portions further include a third wiring portion and a fourth wiring portion; the first wiring portion and the second wiring portion are provided on the first inner surface side of the package, the third wiring portion and the fourth wiring portion are provided on the second inner surface side of the package, the plurality of semiconductor laser elements include one or more third semiconductor laser elements, the second semiconductor laser element is disposed at a position spaced apart from the first semiconductor laser element in the second direction, the one or more third semiconductor laser elements are disposed at positions spaced apart from the second semiconductor laser element in the second direction, The light emitting device according to claim 12 , wherein the plurality of wirings include one or more fifth wirings joined to the third wiring portion and one or more sixth wirings joined to the fourth wiring portion.

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