Semiconductor laser device

Abstract

This semiconductor laser device comprises: a semiconductor laser element (11) and a semiconductor laser element (12); a reflecting mirror (71) that reflects first laser light emitted from the semiconductor laser element (11); and a reflecting mirror (72) that reflects second laser light emitted from the semiconductor laser element (12). The semiconductor laser element (11) has a light emitting point (11e). The semiconductor laser element (12) has a light emitting point (12e). When the optical axis of the first laser light entering the reflecting mirror (71) is a first optical axis, the optical axis of the second laser light entering the reflecting mirror (72) is a second optical axis, and a direction passing through the light emitting point (11e) and perpendicular to the first optical axis is a first direction, a first distance from the light emitting point (11e) to the first optical axis in the first direction and a second distance from the light emitting point (11e) to the second optical axis in the first direction are different from each other. A third distance from the light emitting point (12e) to the second optical axis in the first direction is greater than the first distance.

Description

semiconductor laser device

[0001] The present disclosure relates to a semiconductor laser device.

[0002] Patent Document 1 describes a semiconductor laser device including a multistage base arranged on a flat bottom surface, a plurality of semiconductor laser elements and a plurality of reflecting mirrors arranged on the multistage base, a focusing lens, and an optical fiber. Each of the plurality of semiconductor laser elements and each of the plurality of reflecting mirrors are arranged on each stage of the multistage base. Each of the plurality of laser beams from the plurality of semiconductor laser elements is deflected by the plurality of reflecting mirrors and enters the focusing lens. The focusing lens focuses the incident plurality of laser beams onto the incident end face of the optical fiber.

[0003] The semiconductor laser device described in Patent Document 1 attempts to realize a compact, high-output laser light source with the above-described configuration.

[0004] International Publication No. 2021 / 230294

[0005] When the bottom surface of the semiconductor laser device described in Patent Document 1 is placed on a heat sink, the distances from the multiple semiconductor laser elements to the bottom surface vary, resulting in non-uniform heat dissipation characteristics for the multiple semiconductor laser elements. Furthermore, in the semiconductor laser device described in Patent Document 1, the multiple semiconductor laser elements must be mounted on multiple stages at different heights, making the mounting process complicated. In the semiconductor laser device described in Patent Document 1, the positions of the semiconductor laser elements are determined on a multi-stage base, making it difficult to solve these problems.

[0006] Therefore, an object of the present disclosure is to increase the degree of freedom in arranging a plurality of semiconductor laser elements in a semiconductor laser device including the plurality of semiconductor laser elements.

[0007] In order to achieve the above object, a semiconductor laser device according to one aspect of the present disclosure includes a housing having a bottom surface, a first semiconductor laser element and a second semiconductor laser element disposed in the housing, a first reflecting mirror that reflects a first laser beam emitted from the first semiconductor laser element, a second reflecting mirror that reflects a second laser beam emitted from the second semiconductor laser element, a focusing lens that focuses the first laser beam reflected by the first reflecting mirror and the second laser beam reflected by the second reflecting mirror, a first mirror mounting surface on which the first reflecting mirror is mounted, and a second mirror mounting surface on which the second reflecting mirror is mounted, the first mirror mounting surface and the second mirror mounting surface being parallel to each other, the first semiconductor laser element and the second mirror installation surface are not on the same plane, the first semiconductor laser element has a first light-emitting point from which the first laser light is emitted, the second semiconductor laser element has a second light-emitting point from which the second laser light is emitted, an optical axis of the first laser light incident on the first reflecting mirror is defined as a first optical axis, an optical axis of the second laser light incident on the second reflecting mirror is defined as a second optical axis, and a direction passing through the first light-emitting point and perpendicular to the first optical axis is defined as a first direction, a first distance in the first direction from the first light-emitting point to the first optical axis and a second distance in the first direction from the first light-emitting point to the second optical axis are different from each other, and a third distance in the first direction from the second light-emitting point to the second optical axis is greater than the first distance.

[0008] To achieve the above object, a semiconductor laser device according to another aspect of the present disclosure includes: a housing having a bottom surface; a first semiconductor laser element and a second semiconductor laser element disposed in the housing; a first reflecting mirror that reflects a first laser beam emitted from the first semiconductor laser element; a second reflecting mirror that reflects a second laser beam emitted from the second semiconductor laser element; a focusing lens that focuses the first laser beam reflected by the first reflecting mirror and the second laser beam reflected by the second reflecting mirror; a first collimating element disposed between the first semiconductor laser element and the first reflecting mirror and that deflects a propagation direction of the first laser beam; and a second collimating element disposed between the second semiconductor laser element and the second reflecting mirror and that deflects a propagation direction of the second laser beam, a first optical axis of the first laser light incident on the first reflecting mirror and a second optical axis of the second laser light incident on the second reflecting mirror are parallel, the optical axis of the first laser light incident on the first reflecting mirror is parallel, and the optical axis of the first laser light incident on the first reflecting mirror is tilted with respect to the optical axis of the first laser light incident on the first reflecting element; when the optical axis of the first laser light incident on the first reflecting mirror is defined as a first optical axis and the optical axis of the second laser light incident on the second reflecting mirror is defined as a second optical axis, and a direction passing through the first light-emitting point and perpendicular to the first optical axis is defined as a first direction, a first distance in the first direction from the first light-emitting point to the first optical axis and a second distance in the first direction from the first light-emitting point to the second optical axis are different from each other, and a third distance in the first direction from the second light-emitting point to the second optical axis is greater than the first distance.

[0009] According to the present disclosure, in a semiconductor laser device including a plurality of semiconductor laser elements, the degree of freedom in arranging the plurality of semiconductor laser elements can be increased.

[0010] 1 is a perspective view showing a configuration of a semiconductor laser device according to a first embodiment; FIG. 2 is a plan view showing a configuration of a semiconductor laser device according to the first embodiment; FIG. 3 is a side view showing a configuration of a semiconductor laser device according to the first embodiment; FIG. 4 is a schematic diagram showing a spot shape of laser light on an end face of an optical fiber; FIG. 5 is a plan view showing a configuration of a semiconductor laser device according to a first modification of the first embodiment; FIG. 6 is a side view showing a configuration of a semiconductor laser device according to a first modification of the first embodiment; FIG. 7 is a perspective view showing a configuration of a semiconductor laser device according to a second modification of the first embodiment; FIG. 8 is a perspective view showing a detailed configuration example of an airtight package according to the second embodiment; FIG. 9 is a perspective view showing an internal configuration of an airtight package according to a modification of the second embodiment; FIG. 10 is a plan view showing a configuration of a semiconductor laser device according to a third embodiment; FIG. 11 is a side view showing a configuration of a semiconductor laser device according to the third embodiment; FIG. 12 is a perspective view showing a configuration of a semiconductor laser device according to a fourth embodiment; FIG. 13 is a side view showing a configuration of a semiconductor laser device according to the fourth embodiment; FIG. 14 is a perspective view showing a configuration of a semiconductor laser device according to a first modification of the fourth embodiment; FIG. 15 is a side view showing a configuration of a semiconductor laser device according to a first modification of the fourth embodiment; Fig. 1 is a perspective view showing the configuration of a semiconductor laser device according to a fifth embodiment. Fig. 2 is a side view showing the configuration of a semiconductor laser device according to the fifth embodiment. Fig. 3 is a perspective view showing the configuration of a semiconductor laser device according to a modification of the fifth embodiment. Fig. 4 is a perspective view showing the configuration of a semiconductor laser device according to a third modification of the first embodiment. Fig. 5 is a perspective view showing the configuration of a semiconductor laser device according to a fourth modification of the first embodiment.

[0011] Semiconductor laser devices according to embodiments of the present disclosure will be described in detail below with reference to the drawings. Note that each of the embodiments described below represents a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, component arrangements and connection forms, steps, and step orders shown in the following embodiments are merely examples and are not intended to limit the present disclosure.

[0012] Furthermore, each figure is a schematic diagram and is not necessarily an exact illustration. Therefore, for example, the scales of the figures do not necessarily match. Furthermore, in each figure, substantially the same components are given the same reference numerals, and redundant explanations are omitted or simplified.

[0013] Furthermore, in this specification, terms indicating the relationship between elements, such as "equal," terms indicating the shape of elements, such as "flat," "parallel," "vertical," "plate-shaped," and "curved," as well as numerical ranges, are not expressions that only express a strict meaning, but are expressions that also include a substantially equivalent range, for example, a difference of about a few percent.

[0014] In this specification, the terms "above" and "below" do not refer to vertically above and below in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in a stacked configuration. The terms "above" and "below" are used not only when two components are arranged with a gap between them and another component is present between them, but also when two components are arranged closely together and are in contact with each other.

[0015] First Embodiment A semiconductor laser device according to a first embodiment will be described.

[0016] [1-1. Configuration] The configuration of a semiconductor laser device according to the first embodiment will be described with reference to FIGS. 1 to 3. FIGS. 1, 2, and 3 are a perspective view, a plan view, and a side view, respectively, showing the configuration of a semiconductor laser device 1 according to the present embodiment. In FIGS. 1 to 3, the lid of the housing 2 of the semiconductor laser device 1 and part or all of the side wall 3 are not shown in order to show the interior of the semiconductor laser device 1. Note that each figure shows an X-axis, a Y-axis, and a Z-axis, which are orthogonal to each other. The X-axis, the Y-axis, and the Z-axis form a right-handed Cartesian coordinate system. Hereinafter, a relative position in the X-axis direction may be expressed as "upper" (or "above") or "lower" (or "below"). For example, a position on the positive side of a certain position in the X-axis direction may be expressed as an upper position, and a position on the negative side of the X-axis direction may be expressed as a lower position.

[0017] 1, the semiconductor laser device 1 includes a housing 2, a plurality of semiconductor laser elements 10 to 15, a plurality of reflecting mirrors 70 to 75, a condenser lens 90, and a plurality of mirror mounting surfaces 80 to 85. In this embodiment, the semiconductor laser device 1 further includes submounts 20 to 25, fast-axis collimator lenses 30 to 35, a deflection element 40, collimating elements 51 to 55, slow-axis collimator lenses 60 to 65, an optical fiber 4, a laser base 7, current introduction terminals 9 a, 9 b, and a wiring member 9 c.

[0018] The semiconductor laser device 1 is a module that can spatially combine laser beams emitted from a plurality of semiconductor laser elements 10 to 15 by an optical system and emit the combined laser beams.

[0019] The housing 2 has a bottom 6, side walls 3, and a lid (not shown).

[0020] The bottom 6 is a plate-like member disposed at the bottom (lower end, i.e., the end on the negative side in the X-axis direction in each drawing) of the housing 2. The bottom 6 has a flat bottom surface 6a. The bottom surface 6a is a flat region of the main surface of the bottom 6 that is located inside the housing 2. In other words, the bottom surface 6a is a surface that is in the same plane. In this embodiment, the bottom surface 6a is the entire main surface of the bottom 6. Note that the main surface of the bottom 6 that is located inside the housing 2 may have a non-flat region (i.e., a region other than the bottom surface 6a).

[0021] The sidewalls 3 are disposed perpendicular to the bottom 6 of the housing 2. The sidewalls 3 are disposed so as to surround the semiconductor laser elements 10 to 15. The sidewalls 3 are made of, for example, Cu, a Cu alloy, an Fe—Ni—Co alloy, or Al. The bottom 6 is made of, for example, Cu, a Cu alloy, Al, or a ceramic having high thermal conductivity (for example, AlN or BeO). The lid is a member that covers the upper part of the housing 2.

[0022] The current introduction terminals 9a and 9b are terminals for introducing current from the outside of the housing 2 to the inside of the housing 2. One end of each of the current introduction terminals 9a and 9b is disposed outside the housing 2, and the other end is disposed inside the housing 2. In this embodiment, the current introduction terminals 9a and 9b are disposed on the side wall 3 and penetrate the side wall 3. If the side wall 3 is formed of a conductive material, an insulating member is disposed between the current introduction terminals 9a and 9b and the side wall 3.

[0023] The multiple mirror installation surfaces 80 to 85 are surfaces on which the multiple reflecting mirrors 70 to 75 are respectively installed. That is, the reflecting mirror 70 is installed on the mirror installation surface 80, the reflecting mirror 71 is installed on the mirror installation surface 81, the reflecting mirror 72 is installed on the mirror installation surface 82, the reflecting mirror 73 is installed on the mirror installation surface 83, the reflecting mirror 74 is installed on the mirror installation surface 84, and the reflecting mirror 75 is installed on the mirror installation surface 85. The multiple mirror installation surfaces 80 to 85 have different heights (or average heights) from the bottom surface 6a. Specifically, mirror installation surface 81 is higher from the bottom surface 6a than mirror installation surface 80, mirror installation surface 82 is higher from the bottom surface 6a than mirror installation surface 81, mirror installation surface 83 is higher from the bottom surface 6a than mirror installation surface 82, mirror installation surface 84 is higher from the bottom surface 6a than mirror installation surface 83, and mirror installation surface 85 is higher from the bottom surface 6a than mirror installation surface 84. In this embodiment, mirror installation surfaces 80 to 85 are flat surfaces parallel to the bottom surface 6a.

[0024] The multiple mirror installation surfaces 80 to 85 include a first mirror installation surface and a second mirror installation surface. The mirror installation surface 81 is an example of a first mirror installation surface on which the reflective mirror 71 (first reflective mirror) is installed. The mirror installation surface 82 is an example of a second mirror installation surface on which the reflective mirror 72 (second reflective mirror) is installed.

[0025] In this embodiment, the semiconductor laser device 1 includes a multi-step base 8 having a plurality of mirror mounting surfaces 80 to 85. The multi-step base 8 has a lower surface 8ba, and is mounted on the bottom surface 6a so that the lower surface 8ba is parallel to the bottom surface 6a. The multi-step base 8 has a plurality of stair-like steps. Each of the plurality of steps of the multi-step base 8 has a surface parallel to the lower surface 8ba, and the surfaces parallel to the lower surface 8ba correspond to each of the plurality of mirror mounting surfaces 80 to 85. Therefore, each of the plurality of mirror mounting surfaces 80 to 85 is parallel to the bottom surface 6a. Furthermore, each of the plurality of mirror mounting surfaces 80 to 85 is parallel to one another and is not on the same plane.

[0026] The laser base 7 is a base on which the plurality of semiconductor laser elements 10 to 15 are mounted. In this embodiment, the laser base 7 is a rectangular plate-shaped member having a flat laser mounting surface 7a. The plurality of semiconductor laser elements 10 to 15 are mounted on the laser mounting surface 7a. The laser base 7 is made of, for example, the same material as the bottom 6 of the housing 2.

[0027] The plurality of semiconductor laser elements 10 to 15 are elements that convert input power and emit laser light, and are arranged within the housing 2. The plurality of semiconductor laser elements 10 to 15 are arranged in the Y-axis direction. In this embodiment, the plurality of semiconductor laser elements 10 to 15 are installed on the same plane. The heights of the plurality of semiconductor laser elements 10 to 15 from the bottom surface 6a are the same. Specifically, the plurality of semiconductor laser elements 10 to 15 are installed on the laser installation surface 7a of the laser base 7 via a plurality of submounts 20 to 25, respectively. The semiconductor laser element 11 and the semiconductor laser element 12 are examples of a first semiconductor laser element and a second semiconductor laser element included in the plurality of semiconductor laser elements 10 to 15, respectively.

[0028] Each of the semiconductor laser elements 10-15 is a laser element having a semiconductor laminate film and an optical waveguide formed on a semiconductor substrate. The semiconductor laser elements 10-15 have light-emitting points 10e-15e, respectively, that emit laser beams L0A-L5A (see FIG. 2). The semiconductor laser elements 10-15 convert externally input power to the optical waveguide into stimulated emission light such as laser beams, and emit the light from the light-emitting points 10e-15e, which are at one end of the optical waveguide. The semiconductor laser elements 10-15 emit the laser beams L0A-L5A, respectively (see FIG. 2). Note that in FIGS. 2 and 3, the optical axes of the laser beams L0A-L5A are indicated by dashed lines. Also, in FIG. 3, the diameter (spot size) of each laser beam is indicated by a dashed line. The laser beams L1A and L2A are examples of a first laser beam and a second laser beam, respectively. The light-emitting point 11e is an example of a first light-emitting point from which a first laser beam is emitted, and the light-emitting point 12e is an example of a second light-emitting point from which a second laser beam is emitted.

[0029] The fast axes of the laser beams L0A to L5A are axes in the stacking direction of the semiconductor laminated films of the semiconductor laser elements 10 to 15, and the slow axes, which are orthogonal to the fast axes, are axes parallel to the stacking planes of the semiconductor laminated films and are also parallel to the Y-axis direction in each drawing. In this embodiment, the fast axes of the semiconductor laser elements 10 to 15 are axes in the height direction from the bottom surface 6a (the X-axis direction in each drawing). The wavelength of the laser beams emitted from the semiconductor laser elements 10 to 15 varies depending on the semiconductor material constituting the semiconductor laminated films. For example, by using nitride-based semiconductor laser elements containing Al, Ga, and In nitrides as the main components for the semiconductor laser elements 10 to 15, the semiconductor laser elements 10 to 15 can emit laser beams having peak wavelengths between 350 nm and 550 nm. Furthermore, for example, by using semiconductor laser elements 10 to 15 that are mainly composed of semiconductors made of Al, Ga, In, As, and P, the semiconductor laser elements 10 to 15 can emit laser light having a peak wavelength between 600 nm and 1600 nm. Note that the semiconductor laser elements 10 to 15 are not limited to semiconductor laser elements made of the above semiconductor materials, and the wavelengths of the laser light emitted by the semiconductor laser elements 10 to 15 are not limited to the above wavelengths.

[0030] The semiconductor laser elements 10 to 15 are rectangular in shape and elongated in the waveguiding direction of the optical waveguide. The optical waveguide has a width of, for example, 5 μm to 300 μm and a length of, for example, 500 μm to 5 mm. The semiconductor laser elements 10 to 15 are transverse multimode lasers whose laser light has multiple modes in the slow axis.

[0031] Furthermore, in this embodiment, the multiple semiconductor laser elements 10 to 15 are laser elements in which Fabry-Perot mirrors are formed at both ends of the optical waveguide, but the configuration of the multiple semiconductor laser elements 10 to 15 is not limited to this. For example, the multiple semiconductor laser elements 10 to 15 may be so-called superluminescent diodes in which no mirror is formed on the light-emitting point side of the optical waveguide. Furthermore, the multiple semiconductor laser elements 10 to 15 may be elements for so-called external cavity type semiconductor lasers in which no mirror is formed on the light-emitting point side of the optical waveguide, but a cavity mirror is arranged as a separate component from the multiple semiconductor laser elements 10 to 15 on the side in the direction of emission of the emitted light, thereby performing laser oscillation.

[0032] In this embodiment, current is supplied to the multiple semiconductor laser elements 10-15 from outside the housing 2 via current introduction terminals 9a, 9b and wiring member 9c. The wiring member 9c is a conductive member disposed within the housing 2 and constitutes part of a current path between the current introduction terminals 9a, 9b and the multiple semiconductor laser elements 10-15. The wiring member 9c extends from near the current introduction terminal 9a to near the semiconductor laser element 10. The multiple semiconductor laser elements 10-15 are connected in series using metal wires W. The current introduction terminal 9a is connected to the wiring member 9c via the metal wire W, and the wiring member 9c is connected to the semiconductor laser element 10 via the metal wire W. More specifically, one electrode of the semiconductor laser element 10 is connected to an electrode formed on the submount 20 via a conductive bonding member such as Au or AuSn, and the electrode formed on the submount 20 is connected to the wiring member 9c via the metal wire W. Furthermore, the other electrode of the semiconductor laser element 10 is connected to the semiconductor laser element 11 by a metal wire W. More specifically, one electrode of the semiconductor laser element 11 is connected to an electrode formed on the submount 21, and the electrode formed on the submount 21 is connected to the other electrode of the semiconductor laser element 11 by a metal wire W. The semiconductor laser elements 11 to 15 are connected to each other in the same manner as the semiconductor laser element 10 and the semiconductor laser element 11. The semiconductor laser element 15 is connected to the current introduction terminal 9b by a metal wire W. As described above, by using the wiring member 9c extending from near the current introduction terminal 9a to near the semiconductor laser element 10, the length of the metal wire W can be shortened and interference between multiple metal wires W can be suppressed.

[0033] The submounts 20 to 25 are bases on which the semiconductor laser elements 10 to 15 are mounted, respectively. In this embodiment, the submounts 20 to 25 are mounted on the laser mounting surface 7a of the laser base 7. The submounts 20 to 25 are block-shaped members made of an insulating material such as a crystal, such as AlN or SiC, or a ceramic. Electrodes are formed on the top surfaces of the block-shaped submounts 20 to 25, and are each connected to one electrode of the semiconductor laser elements 10 to 15. The electrodes are made of one or more metal films made of, for example, Ni, Cu, Pt, and Au.

[0034] The plurality of fast-axis collimator lenses 30-35 are respectively disposed between the semiconductor laser elements 10-15 and the deflection element 40 (and the collimation elements 51-55), and are optical elements onto which the laser beams L0A-L5A are incident. The plurality of fast-axis collimator lenses 30-35 collimate the fast-axis direction components of the laser beams L0A-L5A, and emit laser beams L0B-L5B with the fast-axis direction components collimated. The laser beams L1B and L2B are examples of a first laser beam and a second laser beam, respectively.

[0035] For example, lenses having a convex cylindrical surface can be used as the multiple fast-axis collimator lenses 30 to 35. More specifically, for example, plano-convex cylindrical lenses made of glass with an anti-reflection coating formed on the surface can be used as the multiple fast-axis collimator lenses 30 to 35.

[0036] The plurality of fast-axis collimator lenses 30 to 35 include a first fast-axis collimator lens and a second fast-axis collimator lens. The fast-axis collimator lens 31 and the fast-axis collimator lens 32 are examples of the first fast-axis collimator lens and the second fast-axis collimator lens, respectively.

[0037] The deflection element 40 is disposed between the semiconductor laser elements 11-15 and the reflecting mirrors 71-75, and is a deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser beams L1B-L5B (i.e., deflects the laser beams in the height direction). In this embodiment, the deflection element 40 is disposed between the plurality of fast-axis collimator lenses 31-35 and the plurality of parallelizing elements 51-55, and deflects the laser beams L1B-L5B upward (i.e., in the positive direction in the X-axis direction) and emits the deflected laser beams L1C-L5C. The laser beams L1C-L5C are deflected, for example, by 5 degrees or more and 20 degrees or less with respect to the laser beams L1B-L5B. The laser beams L1C and L2C are examples of a first laser beam and a second laser beam, respectively. The deflection element 40 deflects the laser beams L1B-L5B at the same angle. In this embodiment, the laser beam L0B does not enter the deflection element 40. In other words, the deflection element 40 is not disposed on the optical path of the laser beam L0B. Therefore, the laser beam L0B propagates parallel to the bottom surface 6a from the light-emitting point 10e to the reflecting mirror 70 (and the condenser lens 90) without being given a component in the height direction. For example, a transmissive deflection element can be used as the deflection element 40. The transmissive deflection element is, for example, a prism having an entrance surface and an exit surface, and the entrance surface and the exit surface are not parallel to each other.

[0038] The laser beams L0A to L5A and L0B to L5B propagate parallel to the bottom surface 6a in the positive direction of the Z axis between the semiconductor laser elements 10 to 15 and the deflection element 40. Furthermore, the laser beams L0A to L5A and L0B to L5B propagate parallel to each other between these elements.

[0039] The deflection element 40 is an example of a first deflection element that is disposed between the semiconductor laser element 11 (first semiconductor laser element) and the reflecting mirror 71 (first reflecting mirror) and that imparts a component in the height direction from the bottom surface 6 a to the propagation direction of the laser light L1B (first laser light). The deflection element 40 is also an example of a second deflection element that is disposed between the semiconductor laser element 12 (second semiconductor laser element) and the reflecting mirror 72 (second reflecting mirror) and that imparts a component in the height direction from the bottom surface 6 a to the propagation direction of the laser light L2B (second laser light).

[0040] Although the semiconductor laser device 1 includes a single deflection element 40 in this embodiment, it may include multiple deflection elements. For example, the semiconductor laser device 1 may include five deflection elements that impart height components to each of the laser beams L1B to L5B. In this case, for example, the five deflection elements may be installed at the same height from the bottom surface 6a.

[0041] The multiple collimating elements 51 to 55 are disposed between the deflecting element 40 and the reflecting mirrors 71 to 75, respectively, and are deflecting elements that deflect the propagation direction of the laser beams L1C to L5C in a direction parallel to the mirror mounting surfaces 81 to 85 and emit laser beams L1D to L5D. The laser beams L1D and L2D are examples of a first laser beam and a second laser beam, respectively. In this embodiment, the multiple collimating elements 51 to 55 are disposed on the mirror mounting surfaces 81 to 85, respectively. As a result, the heights of the positions where the multiple collimating elements 51 to 55 are disposed from the bottom surface 6a are different from one another. The heights from the bottom surface 6a of the mounting positions increase in the order of the collimating elements 51, 52, 53, 54, and 55. Note that no collimating element is disposed on the optical path of the laser beam L0B. Because the laser beams L1B to L5B are deflected by the deflector element 40 at the same angle, the distance from the deflector element 40 to each of the collimating elements 51 to 55 must be different depending on the height at which each collimating element is installed. In other words, the distance from the deflector element 40 must be longer in the order of the collimating elements 51, 52, 53, 54, and 55. As described above, the laser beams L1C to L5C between the deflector element 40 and the collimating elements 51 to 55 are parallel to one another. Furthermore, the laser beams L1D to L5D are deflected by, for example, 5 degrees or more and 20 degrees or less with respect to the laser beams L1C to L5C. The distances between the deflector element 40 and the collimating elements 51 to 55 are different from one another. For example, the distance between the deflector element 40 and the collimating element 52 is longer than the distance between the deflector element 40 and the collimating element 51. The distance in the Z-axis direction from each collimating element to each semiconductor laser element increases as the height from the bottom surface 6a of the installation position of each collimating element increases. This allows the distance from the deflection element 40 to each collimating element to vary depending on the height from the bottom surface 6a of the installation position of each collimating element. The collimating elements 51 to 55 are installed near the ends of the mirror installation surfaces 81 to 85 that are closer to the semiconductor laser elements 11 to 15. In other words, the distance in the Z-axis direction from the end of each mirror installation surface located between each semiconductor laser element and each collimating element to each collimating element is shorter than the distance in the Z-axis direction from the end to each semiconductor laser element. This reduces the blocking of each laser light by the multi-stage base 8.

[0042] The distance from the end of each mirror mounting surface closest to each semiconductor laser element to each semiconductor laser element increases as the height of each mirror mounting surface from the bottom surface 6 a increases. Also, as the height of each mirror mounting surface from the bottom surface 6 a increases, the length of each mirror mounting surface in the propagation direction (Z-axis direction) of the laser beams L0E to L5E decreases.

[0043] The height from the bottom surface 6a of the regions of the multistage base 8 between the multiple mirror mounting surfaces 80-85 and the multiple semiconductor laser elements 10-15 is lower than the height of the bottom surface 6a of each light-emitting point of the semiconductor laser elements 10-15. This reduces the possibility of the multistage base 8 blocking each laser beam. In this embodiment, the positions of the ends of the multistage base 8 close to each semiconductor laser element coincide with the ends of the multiple mirror mounting surfaces 80-85. In other words, there is no component of the multistage base 8 located between each mirror mounting surface and the laser base 7. This reduces the possibility of the multistage base 8 blocking each laser beam, and also reduces the weight of the multistage base 8.

[0044] Furthermore, at the end of each mirror mounting surface, an end face perpendicular to the bottom face 6a is formed on the multistage base 8. The distance in the Z-axis direction from the end face to each semiconductor laser element increases as the height of each mirror mounting surface from the bottom face 6a increases. This reduces the blocking of laser light by the multistage base 8 between the deflection element 40 and the collimation elements 51 to 55, as shown in FIG. 3 .

[0045] For example, transmissive deflection elements can be used as the plurality of parallelizing elements 51 to 55. The transmissive deflection element is, for example, a prism having an entrance surface and an exit surface, and the entrance surface and the exit surface are not parallel to each other.

[0046] The collimating element 51 is an example of a first collimating element that is disposed between the deflecting element 40 (first deflecting element) and the reflecting mirror 71 (first reflecting mirror) and deflects the propagation direction of the laser light L1C (first laser light) in a direction parallel to the mirror installation surface 81 (first mirror installation surface). The collimating element 52 is also an example of a second collimating element that is disposed between the deflecting element 40 (second deflecting element) and the reflecting mirror 72 (second reflecting mirror) and deflects the propagation direction of the laser light L2C (second laser light) in a direction parallel to the mirror installation surface 82 (second mirror installation surface).

[0047] The multiple slow-axis collimator lenses 60 to 65 are optical elements that are disposed between the multiple fast-axis collimator lenses 30 to 35 and reflecting mirrors 70 to 75, respectively, and onto which the laser beams L0B, L1D to L5D are incident. In this embodiment, the multiple slow-axis collimator lenses 60 to 65 are disposed on mirror mounting surfaces 80 to 85, respectively. As a result, the heights from the bottom surface 6a at the positions where the slow-axis collimator lenses 60 to 65 are disposed are different from one another. The heights from the bottom surface 6a at the positions where the slow-axis collimator lenses are disposed increase in the order of the slow-axis collimator lenses 60, 61, 62, 63, 64, and 65.

[0048] The multiple slow-axis collimator lenses 60 to 65 collimate the slow-axis components of the laser beams L0B and L1D to L5D, respectively. Lenses having convex cylindrical surfaces can be used as the multiple slow-axis collimator lenses 60 to 65. More specifically, plano-convex cylindrical lenses made of glass with an anti-reflection coating formed on the surface can be used as the multiple slow-axis collimator lenses 60 to 65.

[0049] The spot size in the slow-axis direction of each laser beam emitted from the multiple slow-axis collimator lenses 60 to 65 increases as the optical path length from each semiconductor laser element to each slow-axis collimator lens increases. To make the spot sizes in the slow-axis direction of each laser beam emitted from the multiple slow-axis collimator lenses 60 to 65 uniform, the optical path lengths from each of the multiple slow-axis collimator lenses 60 to 65 to each of the multiple semiconductor laser elements 10 to 15 may be made uniform. Accordingly, the positions of each slow-axis collimator lens 60 to 65 in the Z-axis direction differ. As shown in FIG. 2 , the positions of the slow-axis collimator lens 60 and the slow-axis collimator lens 65 in the Z-axis direction differ by ΔL. The distance in the Z-axis direction from each slow-axis collimator lens to each semiconductor laser element decreases as the height of each slow-axis collimator lens from the bottom surface 6 a increases. This makes it possible to make the optical path lengths from each slow axis collimator lens to each semiconductor laser element uniform.

[0050] The plurality of slow-axis collimator lenses 60 to 65 include a first slow-axis collimator lens and a second slow-axis collimator lens. The slow-axis collimator lens 61 and the slow-axis collimator lens 62 are examples of the first slow-axis collimator lens and the second slow-axis collimator lens, respectively.

[0051] The multiple reflecting mirrors 70-75 are optical elements that reflect the multiple laser beams L0E-L5E emitted from the multiple semiconductor laser elements 10-15, respectively, and emit multiple laser beams L0F-L5F. Laser beam L1F and laser beam L2F are examples of a first laser beam and a second laser beam, respectively. In this embodiment, the multiple reflecting mirrors 70-75 deflect the multiple laser beams L0E-L5E by 90 degrees by reflecting them. The multiple reflecting mirrors 70-75 are respectively mounted on multiple mirror mounting surfaces 80-85. As a result, the heights of the positions where the reflecting mirrors 70-75 are mounted from the bottom surface 6a differ from one another. The heights of the reflecting mirrors 70, 71, 72, 73, 74, and 75 increase in order from the bottom surface 6a where they are mounted.

[0052] The multiple reflecting mirrors 70 to 75 include a first reflecting mirror and a second reflecting mirror. The reflecting mirror 71 is an example of a first reflecting mirror that reflects the laser light L1E (first laser light) emitted from the semiconductor laser element 11 (first semiconductor laser element). The reflecting mirror 72 is an example of a second reflecting mirror that reflects the laser light L2E (second laser light) emitted from the semiconductor laser element 12 (second semiconductor laser element). In this specification, the laser light L1E emitted from the semiconductor laser element 11 refers to the laser light L1A emitted from the semiconductor laser element 11 that is incident on the reflecting mirror 71 via the fast-axis collimator lens 31, the deflecting element 40, the collimating element 51, and the slow-axis collimator lens 61. Furthermore, the laser beam L2E emitted from the semiconductor laser element 12 refers to the laser beam L2A emitted from the semiconductor laser element 12 that passes through the fast-axis collimator lens 32, the deflection element 40, the collimating element 52, and the slow-axis collimator lens 62 and is incident on the reflecting mirror 72. The optical axis of the first laser beam that is incident on the first reflecting mirror is referred to as the first optical axis, and the optical axis of the second laser beam that is incident on the second reflecting mirror is referred to as the second optical axis. Hereinafter, the direction that passes through the light-emitting point 11e (first light-emitting point) of the semiconductor laser element 11 and is perpendicular to the first optical axis is also referred to as the first direction.

[0053] 3, when the light-emitting point 11e of the semiconductor laser element 11 is used as a reference, a first distance D1 in the first direction (the X-axis direction in this embodiment) from the light-emitting point 11e (first light-emitting point) of the semiconductor laser element 11 to the optical axis (first optical axis A1) of the laser beam L1E incident on the reflecting mirror 71 is different from a second distance D2 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the optical axis (second optical axis A2) of the laser beam L2E incident on the reflecting mirror 72. Similarly, the distances in the first direction (the X-axis direction in this embodiment) from the light-emitting point 11e of the semiconductor laser element 11 to the optical axes of the laser beams L1E to L5E incident on the reflecting mirrors 71 to 75, respectively, are different from each other.

[0054] The laser beams L1D to L5D and L1E to L5E propagate in the positive direction of the Z axis between the collimating elements 51 to 55 and the reflecting mirrors 71 to 75, respectively, parallel to the bottom surface 6a and parallel to the mirror installation surfaces 81 to 85. Furthermore, the laser beams L1D to L5D propagate parallel to one another.

[0055] The laser beams L0F to L5F emitted from the multiple reflecting mirrors 70 to 75 propagate parallel to one another, do not overlap in their height directions from the bottom surface 6a, and overlap in their positions parallel to the bottom surface 6a. For example, the laser beam L1F emitted from the reflecting mirror 71 and the laser beam L2F emitted from the reflecting mirror 72 propagate parallel to one another, do not overlap in their fast axis directions (height directions from the bottom surface 6a in this embodiment) of the laser beam L1F emitted from the reflecting mirror 71, and overlap in their slow axis directions (direction parallel to the bottom surface 6a in this embodiment). The laser beams L0F to L5F propagate parallel to the bottom surface 6a between the reflecting mirrors 70 to 75 and the condenser lens 90 in the negative Y-axis direction.

[0056] In this embodiment, as described above, the semiconductor laser elements 10 to 15 are arranged on the same plane, and the plurality of reflecting mirrors 70 to 75 are respectively mounted on a plurality of mirror mounting surfaces 80 to 85 that are different in height from one another. Therefore, in this embodiment, the difference in height between the light-emitting point 11e of the semiconductor laser element 11 from the bottom surface 6a and the mirror mounting surface 81 from the bottom surface 6a is greater than the difference in height between the light-emitting point 10e of the semiconductor laser element 10 from the bottom surface 6a and the mirror mounting surface 80 from the bottom surface 6a. Similarly, the difference in height between the light-emitting point 12e of the semiconductor laser element 12 from the bottom surface 6a and the mirror mounting surface 82 from the bottom surface 6a is greater than the difference in height between the light-emitting point 11e of the semiconductor laser element 11 from the bottom surface 6a and the mirror mounting surface 81 from the bottom surface 6a. In other words, as shown in FIG. 3 , a third distance D3 in a first direction (in this embodiment, the X-axis direction) from the light-emitting point 12e (second light-emitting point) of the semiconductor laser element 12 to the optical axis (second optical axis A2) of the laser light L2E incident on the reflecting mirror 72 is greater than the distance in the first direction from the light-emitting point 11e (first light-emitting point) of the semiconductor laser element 11 to the optical axis (first optical axis A1) of the laser light L1E incident on the reflecting mirror 71.

[0057] In this way, in this embodiment, the difference between the height of one light-emitting point and the height of the mirror installation surface corresponding to that light-emitting point varies for each combination of the light-emitting point and the mirror installation surface. Note that each difference here is defined as the absolute value of the value resulting from the subtraction. Each difference described below is also defined as an absolute value.

[0058] In this embodiment, for example, the difference in height between the light-emitting point 11e of the semiconductor laser element 11 and the light-emitting point 12e of the semiconductor laser element 12 from the bottom surface 6a is smaller than the difference in height between the mirror installation surface 81 and the mirror installation surface 82 from the bottom surface 6a. In other words, as shown in Fig. 3, the distance in the first direction from the light-emitting point 11e (first light-emitting point) of the semiconductor laser element 11 to the light-emitting point 12e (second light-emitting point) of the semiconductor laser element 12 is smaller than a fourth distance D4 in the first direction from the optical axis (first optical axis A1) of the laser light L1E incident on the reflecting mirror 71 to the optical axis (second optical axis A2) of the laser light L2E incident on the reflecting mirror 72. In this embodiment, the distance in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the light-emitting point 12e of the semiconductor laser element 12 is zero and is not shown in Fig. 3. In this manner, in this embodiment, the deviation in height of the semiconductor laser elements 10 to 15 from the bottom surface 6a can be reduced more than the deviation in height of the reflecting mirrors 70 to 75 from the bottom surface.

[0059] The multiple reflecting mirrors 70 to 75 include a first reflecting mirror and a second reflecting mirror. The reflecting mirror 71 is an example of a first reflecting mirror that reflects the laser light L1E (first laser light) emitted from the semiconductor laser element 11 (first semiconductor laser element). The reflecting mirror 72 is an example of a second reflecting mirror that reflects the laser light L2E (second laser light) emitted from the semiconductor laser element 12 (second semiconductor laser element). In this specification, the laser light L1E emitted from the semiconductor laser element 11 refers to the laser light L1A emitted from the semiconductor laser element 11 that is incident on the reflecting mirror 71 via the fast-axis collimator lens 31, the deflecting element 40, the collimating element 51, and the slow-axis collimator lens 61. Furthermore, the laser light L2E emitted from the semiconductor laser element 12 refers to the laser light L2A emitted from the semiconductor laser element 12 that is incident on the reflecting mirror 72 via the FAST axis collimator lens 32, the deflection element 40, the parallelization element 52, and the SLOW axis collimator lens 62.

[0060] The condenser lens 90 is a lens that condenses the multiple laser beams L0F to L5F reflected by the multiple reflecting mirrors 70 to 75. In this embodiment, the condenser lens 90 condenses the laser beams L0F to L5F so that most of the multiple laser beams L0F to L5F are incident on the end face of the optical fiber 4 and can propagate through the optical fiber 4. For example, a spherical lens can be used as the condenser lens 90. Here, the spot shape of the laser beams L0F to L5F on the condenser lens 90 will be described with reference to FIG. 4. FIG. 4 is a schematic diagram showing the spot shape of the laser beams L0F to L5F on the incident surface of the condenser lens 90. In FIG. 4, the outlines of the laser beams L0F to L5F are indicated by dashed lines. As shown in FIG. 4, in this embodiment, overlap of the laser beams L0F to L5F on the condenser lens 90 is reduced.

[0061] The optical fiber 4 is a member that guides the laser beams L0F to L5F from the inside to the outside of the housing 2. As described above, the laser beams L0F to L5F emitted from the condenser lens 90 are incident on the end face of the optical fiber 4 that is disposed inside the housing 2 at the same position but at different angles of incidence. As shown in Fig. 4, in this embodiment, the overlap of the laser beams L0F to L5F at the condenser lens 90 is reduced, and therefore deterioration and damage to the optical fiber 4 that would be caused by the laser beams L0F to L5F concentrating on one part of the end face of the optical fiber 4 can be suppressed.

[0062] [1-2. Effects, etc.] The effects, etc. of the semiconductor laser device 1 according to this embodiment will be described.

[0063] As described above, the semiconductor laser device 1 according to one aspect of the present embodiment includes a housing 2 having a bottom surface 6a, the semiconductor laser element 11 and the semiconductor laser element 12 disposed within the housing 2, a reflecting mirror 71 that reflects the laser light L1E emitted from the semiconductor laser element 11, a reflecting mirror 72 that reflects the laser light L2E emitted from the semiconductor laser element 12, a focusing lens 90 that focuses the laser light L1F reflected by the reflecting mirror 71 and the laser light L2F reflected by the reflecting mirror 72, a mirror mounting surface 81 on which the reflecting mirror 71 is mounted, and a mirror mounting surface 82 on which the reflecting mirror 72 is mounted. The mirror mounting surface 81 and the mirror mounting surface 82 are parallel to each other. The mirror mounting surface 81 and the mirror mounting surface 82 are not coplanar. The semiconductor laser element 11 has a light-emitting point 11e that emits the laser light L1A, and the semiconductor laser element 12 has a light-emitting point 12e that emits the laser light L2A. The optical axis of the laser beam L1E incident on the reflecting mirror 71 is defined as a first optical axis A1, and the optical axis of the laser beam L2E incident on the reflecting mirror 72 is defined as a second optical axis A2. A first distance D1 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the first optical axis A1 is different from a second distance D2 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the second optical axis A2. A third distance D3 in the first direction from the light-emitting point 12e of the semiconductor laser element 12 to the second optical axis A2 is greater than the first distance D1. In other words, the difference in height between the light-emitting point 12e of the second semiconductor laser element from the bottom surface 6a and the height of the mirror installation surface 82 from the bottom surface 6a is greater than the difference in height between the light-emitting point 11e of the first semiconductor laser element from the bottom surface 6a and the height of the mirror installation surface 81 from the bottom surface 6a.

[0064] As described above, in the semiconductor laser device 1, it is not necessary to align the difference in height between each light-emitting point and each mirror mounting surface from the bottom surface 6a. This increases the degree of freedom in arranging each semiconductor laser element. For example, it becomes possible to reduce the height of each semiconductor laser element from the bottom surface 6a. This allows the heat dissipation characteristics of each semiconductor laser element to be improved by connecting a heat sink to the bottom 6.

[0065] Moreover, a semiconductor laser device 1 according to another aspect of the present embodiment includes a housing 2 having a bottom surface 6 a, semiconductor laser elements 11 and 12 arranged in the housing 2, a reflecting mirror 71 that reflects laser light L1E emitted from the semiconductor laser element 11, a reflecting mirror 72 that reflects laser light L2E emitted from the semiconductor laser element 12, and a condenser lens 90 that condenses the laser light L1F reflected by the reflecting mirror 71 and the laser light L2F reflected by the reflecting mirror 72. The semiconductor laser device 1 further includes a collimating element 51 that is arranged between the semiconductor laser element 11 and the reflecting mirror 71 and that deflects the propagation direction of the laser light L1C, and a collimating element 52 that is arranged between the semiconductor laser element 12 and the reflecting mirror 72 and that deflects the propagation direction of the laser light L2C. The semiconductor laser element 11 has an emission point 11e that emits laser light L1A, and the semiconductor laser element 12 has an emission point 12e that emits laser light L2A. The fast axis direction of the laser light L1A at the emission point 11e of the semiconductor laser element 11 is parallel to the first direction. The optical axis of the laser light L1C that enters the collimating element 51 is parallel to the optical axis of the laser light L2C that enters the collimating element 52. The optical axis of the laser light L1E that enters the reflecting mirror 71 is parallel to the optical axis of the laser light L2E that enters the reflecting mirror 72. The optical axis of the laser light L1E that enters the reflecting mirror 71 is tilted with respect to the optical axis of the laser light L1C that enters the collimating element 51. The optical axis of the laser light L1E that enters the reflecting mirror 71 is referred to as a first optical axis A1, and the optical axis of the laser light L2E that enters the reflecting mirror 72 is referred to as a second optical axis A2. A first distance D1 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the first optical axis A1 is different from a second distance D2 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the second optical axis A2. A third distance D3 in the first direction from the light-emitting point 12e of the semiconductor laser element 12 to the second optical axis A2 is greater than the first distance D1.

[0066] In this way, by using each collimating element in the semiconductor laser device 1, it is no longer necessary to align the distance from each light-emitting point to the optical axis of the laser light incident on each reflecting mirror. In other words, it is no longer necessary to align the difference between the height of each light-emitting point from the bottom surface 6a and the height of each mirror mounting surface from the bottom surface 6a. This increases the degree of freedom in arranging each semiconductor laser element. For example, it becomes possible to reduce the height of each semiconductor laser element from the bottom surface 6a. As a result, by connecting a heat sink to the bottom 6, the heat dissipation characteristics of each semiconductor laser element can be improved.

[0067] Furthermore, in the semiconductor laser device 1 according to the present embodiment, the difference in height between the light-emitting point 11e of the semiconductor laser element 11 and the light-emitting point 12e of the semiconductor laser element 12 from the bottom surface 6a may be smaller than the difference in height between the mirror installation surface 81 and the mirror installation surface 82 from the bottom surface 6a. In other words, the distance in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the light-emitting point 12e of the semiconductor laser element 12 may be smaller than a fourth distance D4 in the first direction from the first optical axis A1 to the second optical axis A2.

[0068] In this way, the difference in height between each semiconductor laser element and the bottom surface 6a can be reduced, which facilitates the mounting of each semiconductor laser element. Furthermore, when a heat sink is connected to the bottom 6 and heat is dissipated from the bottom 6, the heat dissipation characteristics change depending on the distance between each semiconductor laser element and the bottom surface 6a. Therefore, by reducing the difference in height between each semiconductor laser element and the bottom surface 6a, the difference in heat dissipation characteristics between each semiconductor laser element can be reduced. This reduces the difference in characteristics such as the wavelength of the laser light from each semiconductor laser element.

[0069] In the semiconductor laser device 1 according to this embodiment, the semiconductor laser elements 10 to 15 may be disposed on the same plane.

[0070] This makes it easier to mount the multiple semiconductor laser elements 10 to 15. Furthermore, for example, when wiring the multiple semiconductor laser elements 10 to 15 using metal wires W to supply current to the semiconductor laser elements, the height of the bond portions of the wire bonds can be made uniform, making wire bonding easier.

[0071] In the semiconductor laser device 1 according to the present embodiment, the fast axis direction of the plurality of semiconductor laser elements 10 to 15 may be the height direction from the bottom surface 6a.

[0072] This makes it possible to improve the heat dissipation characteristics of each semiconductor laser element.

[0073] Furthermore, the semiconductor laser device 1 according to this embodiment may include: a deflecting element 40 (first deflecting element) that is disposed between the semiconductor laser element 11 and the reflecting mirror 71 and that imparts a first direction component to the propagation direction of the laser light L1B; a collimating element 51 that is disposed between the deflecting element 40 and the reflecting mirror 71 and that deflects the propagation direction of the laser light L1C, which has been given the first direction component in its propagation direction, in a direction parallel to the mirror installation surface 81; a deflecting element 40 (second deflecting element) that is disposed between the semiconductor laser element 12 and the reflecting mirror 72 and that imparts the first direction component to the propagation direction of the laser light L2B; and a collimating element 52 that is disposed between the deflecting element 40 and the reflecting mirror 72 and that deflects the propagation direction of the laser light L2C, which has been given the first direction component in its propagation direction, in a direction parallel to the mirror installation surface 82.

[0074] This allows the propagation direction of each laser light to be parallel to each mirror installation surface without installing each semiconductor laser element at a height corresponding to each mirror installation surface, and allows the height of each laser light to be guided to a height at which it is incident on each reflecting mirror.

[0075] In the semiconductor laser device 1 according to the present embodiment, the collimating element 51 may be installed on the mirror installation surface 81 , and the collimating element 52 may be installed on the mirror installation surface 82 .

[0076] This makes it easier to guide each laser beam from each collimating element to each reflecting mirror, and also makes it easier to adjust the height of each collimating element.

[0077] Furthermore, in the semiconductor laser device 1 according to this embodiment, the laser light L1C between the deflection element 40 and the parallelization element 51 and the laser light L2C between the deflection element 40 and the parallelization element 52 are parallel, and the distance between the deflection element 40 and the parallelization element 52 may be longer than the distance between the deflection element 40 and the parallelization element 51.

[0078] This makes it possible to make the difference in height between the light-emitting point 12e of the semiconductor laser element 12 from the bottom surface 6a and the height of the mirror mounting surface 82 from the bottom surface 6a larger than the difference in height between the light-emitting point 11e of the semiconductor laser element 11 from the bottom surface 6a and the height of the mirror mounting surface 81 from the bottom surface 6a.

[0079] In the semiconductor laser device 1 according to the present embodiment, each of the deflection element 40, the collimation element 51, and the collimation element 52 may be a transmissive deflection element.

[0080] In the semiconductor laser device 1 according to the present embodiment, the transmissive deflection element is a prism having an incident surface and an exit surface, which do not have to be parallel to each other, thereby enabling the angle of optical path deflection to be adjusted more precisely than the installation angle of the prism.

[0081] The semiconductor laser device 1 according to this embodiment may also include a fast-axis collimator lens 31 disposed between the semiconductor laser element 11 and the collimating element 51 .

[0082] This makes it possible to suppress an increase in the spot size of the laser light L1A in the fast axis direction.

[0083] The semiconductor laser device 1 according to this embodiment may also include a slow-axis collimator lens 61 disposed between the fast-axis collimator lens 31 and the reflecting mirror 71 .

[0084] This makes it possible to suppress an increase in the spot size of the laser light L1D in the SLOW axis direction.

[0085] Furthermore, in the semiconductor laser device 1 according to this embodiment, the propagation directions of the laser light L1F emitted from the reflecting mirror 71 and the laser light L2F emitted from the reflecting mirror 72 may be parallel, and the positions of the laser light L1F in the fast axis direction may not overlap, but the positions of the laser light L1F in the slow axis direction may overlap.

[0086] In this way, by making the propagation directions of the laser light L1F and the laser light L2F parallel and aligning the position of the laser light L1F in the SLOW axis direction, the laser light L1F and the laser light L2F can be easily focused onto the optical fiber 4, etc. Furthermore, by not overlapping the positions of the laser light L1F and the laser light L2F in the FAST axis direction, it is possible to prevent the laser light intensity from becoming locally high, and therefore it is possible to prevent deterioration and damage to optical elements such as the optical fiber 4 into which each laser light is incident.

[0087] [1-3. Modification 1] A semiconductor laser device according to Modification 1 of the present embodiment will be described. The semiconductor laser device according to this modification differs from the above-described semiconductor laser device 1 mainly in that the laser light is deflected downward by a deflection element. The semiconductor laser device according to this modification will be described below with reference to FIGS. 5 and 6, focusing on the differences from the semiconductor laser device 1.

[0088] 5 and 6 are a plan view and a side view showing the configuration of a semiconductor laser device 1a according to this modification. As shown in Fig. 5, the semiconductor laser device 1a according to this modification includes a housing 2, a plurality of semiconductor laser elements 10-12, a plurality of submounts 20-22, a plurality of fast-axis collimator lenses 30-32, a deflector 40a, a plurality of parallelizing elements 51a, 52a, a plurality of slow-axis collimator lenses 60-62, a plurality of reflecting mirrors 70-72, a plurality of mirror mounting surfaces 80a-82a, an optical fiber 4, and current input terminals 9a, 9b.

[0089] In this modification, the semiconductor laser device 1a includes a multi-stage base 8a having a plurality of mirror mounting surfaces 80a to 82a.

[0090] The multiple mirror mounting surfaces 80a-82a are surfaces on which the multiple reflecting mirrors 70-72 are respectively mounted. The multiple mirror mounting surfaces 80a-82a have different heights from the bottom surface 6a. Specifically, the mirror mounting surface 81a is lower in height from the bottom surface 6a than the mirror mounting surface 80a, and the mirror mounting surface 82a is lower in height from the bottom surface 6a than the mirror mounting surface 81a. The mirror mounting surface 80a is at the same height as the upper surface of the multi-stage base 8a. The mirror mounting surfaces 81a and 82a are formed at a position lower than the upper surface, and there is a step between the ends of the mirror mounting surfaces 81a and 82a and the upper surface of the multi-stage base 8a.

[0091] In this modification, the semiconductor laser elements 10-12, the submounts 20-22, the fast-axis collimator lenses 30-32, and the deflector 40a are disposed on the upper surface of the multistage base 8a. The slow-axis collimator lens 60 and the reflecting mirror 70 are disposed on the mirror mounting surface 80a.

[0092] As shown in FIG. 6 , the deflection element 40a according to this modification is disposed between the semiconductor laser elements 11 and 12 and the reflecting mirrors 71 and 72, and is a deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser beams L1B and L2B. In this modification, the deflection element 40a is disposed between the plurality of fast-axis collimator lenses 31 and 32 and the plurality of parallelizing elements 51a and 52a, and deflects the laser beams L1B and L2B downward (i.e., in the negative X-axis direction). The deflection element 40a deflects the laser beams L1B and L2B at the same angle. The deflection element 40a is disposed between the semiconductor laser element 11 (first semiconductor laser element) and the reflecting mirror 71 (first reflecting mirror), and is an example of a first deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser beam L1B (first laser beam). In addition, the deflection element 40a is disposed between the semiconductor laser element 12 (second semiconductor laser element) and the reflecting mirror 72 (second reflecting mirror), and is also an example of a second deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser light L2B (second laser light).

[0093] The multiple collimating elements 51a, 52a are disposed between the deflecting element 40a and the reflecting mirrors 71, 72, respectively, and are deflecting elements that deflect the propagation direction of the laser beams L1C, L2C in a direction parallel to the mirror mounting surfaces 81a, 82a. In this modification, the multiple collimating elements 51a, 52a are mounted on the mirror mounting surfaces 81a, 82a, respectively. As a result, the heights from the bottom surface 6a at the positions where the multiple collimating elements 51a, 52a are mounted are different from each other. The heights from the bottom surface 6a at the mounting positions of the collimating elements 51a, 52a decrease in order. The distance in the Z-axis direction of each of the collimating elements 51a, 52a from the corresponding semiconductor laser element increases as the height from the bottom surface 6a at the mounting position of each collimating element decreases. This allows the distances of the parallelizing elements 51a and 52a from the deflection element 40a to be different depending on the height from the bottom surface 6a of the installation position of each parallelizing element.

[0094] In this embodiment, a step is formed between the end of the mirror mounting surfaces 81a, 82a closer to the semiconductor laser elements 11, 12 and the upper surface of the multi-stage base 8a. The deflection element 40a is mounted on the upper surface of the multi-stage base 8a near this step. The distance in the Z-axis direction from the step to the collimating element 51a is longer than the distance in the Z-axis direction from the step to the deflection element 40a. This reduces the possibility of laser light being blocked by the multi-stage base 8a between the deflection element 40a and the collimating element 51a, as shown in FIG. 6 .

[0095] Furthermore, the distance in the Z-axis direction from each of the slow-axis collimator lenses 60 to 62 to each semiconductor laser element becomes smaller as the height of each slow-axis collimator lens from the bottom surface 6 a decreases, thereby making it possible to make the optical path lengths between each slow-axis collimator lens and each semiconductor laser element uniform.

[0096] The semiconductor laser device 1a having such a configuration also achieves the same effects as those of the semiconductor laser device 1 according to the first embodiment.

[0097] [1-4. Modification 2] A semiconductor laser device according to Modification 2 of the present embodiment will be described. The semiconductor laser device according to this modification differs from the semiconductor laser device 1a according to Modification 1 described above mainly in that the laser light is also deflected upward by a deflection element. The semiconductor laser device according to this modification will be described below with reference to FIGS. 7 and 8, focusing on the differences from the semiconductor laser device 1a according to Modification 1.

[0098] 7 and 8 are a plan view and a side view showing the configuration of a semiconductor laser device 1b according to this modification. As shown in Fig. 7, the semiconductor laser device 1b according to this modification includes a housing 2, a plurality of semiconductor laser elements 10 to 14, a plurality of submounts 20 to 24, a plurality of fast-axis collimator lenses 30 to 34, deflection elements 40a and 40b, a plurality of parallelizing elements 51a to 54a, a plurality of slow-axis collimator lenses 60 to 64, a plurality of reflecting mirrors 70 to 74, a plurality of mirror mounting surfaces 80a to 84a, an optical fiber 4, and current input terminals 9a and 9b.

[0099] In this modification, the semiconductor laser device 1b includes a multi-stage base 8b having a plurality of mirror mounting surfaces 80a to 84a.

[0100] The multiple mirror installation surfaces 83a, 84a are surfaces on which the multiple reflecting mirrors 73, 74 are respectively installed. The multiple mirror installation surfaces 80a to 84a have different heights from the bottom surface 6a. Specifically, the mirror installation surface 83a is higher from the bottom surface 6a than the mirror installation surface 80a, and the mirror installation surface 84a is higher from the bottom surface 6a than the mirror installation surface 83a.

[0101] In this modification, the semiconductor laser elements 10 to 14, the submounts 20 to 24, the fast axis collimator lenses 30 to 34, and the deflection elements 40a and 40b are arranged on the upper surface of the multi-stage base 8b.

[0102] As shown in FIG. 8 , the deflection element 40b according to this modification is disposed between the semiconductor laser elements 13, 14 and the reflecting mirrors 73, 74, and is a deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser beams L3B, L4B. In this modification, the deflection element 40b is disposed between the multiple fast-axis collimator lenses 33, 34 and the multiple parallelizing elements 53a, 54a, and deflects the laser beams L3B, L4B upward (i.e., in the positive direction in the X-axis direction). The deflection element 40b deflects the laser beams L3B, L4B at the same angle. The deflection element 40b is disposed between the semiconductor laser element 13 and the reflecting mirror 73, and is an example of a first deflection element that imparts a height component from the bottom surface 6a to the propagation direction of the laser beams L3B. Furthermore, deflection element 40b is disposed between semiconductor laser element 14 and reflection mirror 74, and is also an example of a second deflection element that imparts a height component from bottom surface 6a to the propagation direction of laser beam L4B. Here, semiconductor laser element 13 and semiconductor laser element 14 are examples of a first semiconductor laser element and a second semiconductor laser element, respectively. Reflection mirrors 73 and 74 are examples of a first reflection mirror and a second reflection mirror, respectively. Laser beam L3B and laser beam L4B are examples of a first laser beam and a second laser beam, respectively.

[0103] The multiple collimating elements 53a, 54a are disposed between the deflecting element 40b and the reflecting mirrors 73, 74, respectively, and are deflecting elements that deflect the propagation direction of the laser beams L3C, L4C in a direction parallel to the mirror mounting surfaces 83a, 84a. In this modification, the multiple collimating elements 53a, 54a are mounted on the mirror mounting surfaces 83a, 84a, respectively. As a result, the heights from the bottom surface 6a at the positions where the multiple collimating elements 53a, 54a are mounted are different from one another. The heights from the bottom surface 6a at the mounting positions of the parallelizing elements 53a, 54a increase in the order of the parallelizing elements 53a, 54a.

[0104] The semiconductor laser device 1b having such a configuration also provides the same effects as those of the semiconductor laser device 1a according to the first modification.

[0105] Furthermore, in this modification, the distance in the Z-axis direction between an end of the mirror mounting surface 83a located between the deflection element 40b and the collimating element 53a and the installation position of the collimating element 53a is smaller than the distance in the Z-axis direction between the end and the deflection element 40b, thereby reducing the blocking of the laser light L3C by the multi-stage base 8b.

[0106] (Embodiment 2) A semiconductor laser device according to embodiment 2 will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 1 according to embodiment 1 in that the semiconductor laser element is disposed in an airtight package. The semiconductor laser device according to this embodiment will be described below, focusing on the differences from the semiconductor laser device 1 according to embodiment 1.

[0107] [2-1. Basic Configuration] The basic configuration of a semiconductor laser device according to this embodiment will be described with reference to FIG. 9 . FIG. 9 is a perspective view showing the configuration of a semiconductor laser device 101 according to this embodiment. As shown in FIG. 9 , the semiconductor laser device 101 includes a housing 2, a plurality of semiconductor laser elements 10-12, a plurality of submounts 20-22, a plurality of fast-axis collimator lenses 30-32, a deflection element 40, a plurality of parallelizing elements 51, 52, a plurality of slow-axis collimator lenses 60-62, a plurality of reflecting mirrors 70-72, a plurality of mirror mounting surfaces 80-82, an optical fiber 4, and current input terminals 9a, 9b. In this embodiment, the semiconductor laser device 101 further includes an airtight package 107. The semiconductor laser device 101 also includes a multi-stage base 108 having a plurality of mirror mounting surfaces 80-82. In this embodiment, the number of semiconductor laser elements and the like is three, but similar to the first embodiment, the number of semiconductor laser elements and the like may be four or more.

[0108] The airtight package 107 is a package that hermetically seals at least one of the plurality of semiconductor laser elements 10 to 12. In this embodiment, the airtight package 107 is a single package that hermetically seals the plurality of semiconductor laser elements 10 to 12. The submounts 20 to 22 are also hermetically sealed within the airtight package 107. The airtight package 107 has a light-transmitting window 117 for emitting the laser light from each of the plurality of semiconductor laser elements 10 to 12 to the outside of the airtight package 107.

[0109] As described above, the semiconductor laser device 101 according to this embodiment includes the hermetic package 107 that hermetically seals at least one of the plurality of semiconductor laser elements 10 to 12 .

[0110] As a result, for example, when the plurality of semiconductor laser elements 10 to 12 include an AlGaInN-based semiconductor and emit laser light of wavelengths corresponding to blue light to ultraviolet light, it is possible to suppress deterioration of each semiconductor laser element due to organic matter adhering to the light-emitting point of each semiconductor laser element.

[0111] Furthermore, the semiconductor laser device 101 according to this embodiment includes a single airtight package 107 that hermetically seals the semiconductor laser element 11 (first semiconductor laser element) and the semiconductor laser element 12 (second semiconductor laser element). This simplifies the configuration compared to when the multiple semiconductor laser elements 10 to 12 are individually airtight sealed. Furthermore, the airtight package 107 can be attached to the housing 2 more easily than when multiple airtight packages are used.

[0112] [2-2. Detailed Configuration Example of Airtight Package] A detailed configuration example of the airtight package 107 of the semiconductor laser device 101 according to this embodiment will be described with reference to Fig. 10. Fig. 10 is a perspective view showing a detailed configuration example of the airtight package 107 according to this embodiment. In Fig. 10, in order to show the inside of the airtight package 107, a lid covering an opening P01 of the airtight package 107 is shown removed.

[0113] The airtight package 107 includes a first package P21, a light-transmitting window 117, and a lid (not shown).

[0114] 10, the first package P21 has a frame body P20, a package bottom P30, and a power supply member formed on the frame body P20. In the first package P21, the frame body P20 is stacked and fixed to the package bottom P30.

[0115] The package bottom P30 is a plate-shaped member made of an inorganic material with high thermal conductivity. The package bottom P30 may be made of a metal such as Cu or a Cu alloy, or may be made of a ceramic or polycrystalline material such as AlN, SiC, or diamond.

[0116] The frame P20 is a frame-shaped member that exists mainly around the periphery of the package bottom P30 and has an opening P01 that opens at the center in plan view. The opening P01 has a rectangular shape in plan view. The frame P20 is a member made primarily of an inorganic insulating material such as alumina ceramic or AlN ceramic. The upper surface of the portion of the package bottom P30 near the center that is not covered by the frame P20 serves as the semiconductor laser element mounting surface.

[0117] Power supply members are provided inside and on the surface of the frame P20. The power supply members are made up of an anode lead-out electrode P31, a cathode lead-out electrode P34, an anode electrode P32, and a cathode electrode P35, which are made up of patterned metal wiring.

[0118] An opening (not shown) for extracting laser light is formed on one side of the first package P21. A light-transmitting window 117 is provided in the frame body P20 so as to cover the opening.

[0119] The anode output electrode P31 is an electrode that connects the anode electrode P32 and a current introduction terminal 9a that is arranged outside the airtight package 107, and the cathode output electrode P34 is an electrode that connects the cathode electrode P35 and a current introduction terminal 9b that is arranged outside the airtight package 107. The anode output electrode P31 and the cathode output electrode P34 are formed on the upper surface of the frame body P20.

[0120] The anode lead-out electrode P31 and the cathode lead-out electrode P34 are electrically connected to the anode electrode P32 and the cathode electrode P35, respectively, by metal wiring, via electrodes, or the like.

[0121] As described above, the airtight package 107 can form an airtight space by the package bottom P30, the frame body P20, the light-transmitting window 117, and the lid.

[0122] The semiconductor laser elements 10 to 12 are arranged in the airtight space of the airtight package 107. In this configuration example, the semiconductor laser elements 10 to 12 are arranged on a single submount 120. In other words, the submount 120 is a member in which the submounts 20 to 22 are integrated.

[0123] Four patterned metal films 126-129 are arranged on the upper surface of the submount 120 while being insulated from one another. The four metal films 126-129 are arranged in the Y-axis direction. The semiconductor laser elements 10-12 are mounted on the metal films 126-129, respectively, via conductive bonding members. The four metal films 126-129 are made of one or more metal films selected from the group consisting of Ni, Cu, Pt, and Au. In this embodiment, the submount 120 is a separate component from the first package P21, but it may also be formed integrally as part of the first package P21.

[0124] The cathode electrode P35 is connected to the metal film 129 by a metal wire W. The metal film 129 is connected to an electrode on the top surface of the semiconductor laser element 12 by a metal wire W. The metal film 128 is connected to an electrode on the top surface of the semiconductor laser element 11 by a metal wire W. The metal film 127 is connected to an electrode on the top surface of the semiconductor laser element 10 by a metal wire W. The metal film 126 is connected to the anode electrode P32 by a metal wire W.

[0125] This allows for serial connection of the semiconductor laser elements 10 to 12. In this configuration example, the semiconductor laser elements 10 to 12 are mounted junction-down on the submount 120, but they may also be mounted junction-up.

[0126] Furthermore, a fast-axis collimator lens 130 is disposed on the optical path of the laser beams L0A to L2A (not shown in FIG. 10) inside the package. The fast-axis collimator lens 130 is an integrated version of the fast-axis collimator lenses 30 to 32.

[0127] As described above, by hermetically sealing the semiconductor laser elements 10 to 12 and the like in the hermetic package 107, deterioration of the semiconductor laser elements 10 to 12 and the like can be suppressed.

[0128] [2-3. Detailed Configuration Example of Modified Example] A detailed configuration example of a modified example of the present embodiment will be described. This modified example differs from the above detailed configuration example mainly in that the semiconductor laser elements 10 to 12 are integrated. Below, the detailed configuration example of this modified example will be described, focusing on the differences from the above detailed configuration example, using FIG. 11. FIG. 11 is a perspective view showing the internal configuration of an airtight package 107 according to the modified example of the present embodiment.

[0129] As shown in FIG. 11 , the semiconductor laser elements 10 to 12 according to this modification are integrated to form a semiconductor laser array 110. In other words, the semiconductor laser elements 10 to 12 are included in the semiconductor laser array 110, which is a single element. Three optical waveguides formed in the semiconductor laser array 110 correspond to the semiconductor laser elements 10 to 12. In this modification, an electrode is formed on the upper surface of the semiconductor laser array 110, integrally covering at least portions corresponding to the three optical waveguides. Also, an electrode is formed on the lower surface of the semiconductor laser array 110, integrally covering at least portions corresponding to the three optical waveguides. By using such a semiconductor laser array 110, multiple semiconductor laser elements 10 to 12 can be mounted together, thereby simplifying the manufacturing process. Furthermore, since it is not necessary to adjust the relative positions of the multiple semiconductor laser elements 10 to 12, the manufacturing process can be further simplified.

[0130] In this modification, two patterned metal films 126 and 129 are arranged insulated from each other on the upper surface of the submount 120. The semiconductor laser array 110 is mounted on the metal film 126 via a conductive bonding member.

[0131] The cathode electrode P35 is connected to the metal film 129 by a metal wire W. The metal film 129 is connected to an electrode on the upper surface of the semiconductor laser array 110 by a metal wire W. The metal film 126 is connected to the anode electrode P32 by a metal wire W.

[0132] This makes it possible to realize the semiconductor laser elements 10 to 12 connected in parallel.

[0133] The detailed configuration example according to this modified example also provides the same effects as the detailed configuration example described above.

[0134] (Embodiment 3) A semiconductor laser device according to embodiment 3 will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 1 according to embodiment 1 mainly in that the deflection element and the parallelization element have reflecting surfaces. The semiconductor laser device according to this embodiment will be described below with reference to FIGS. 12 and 13, focusing on the differences from the semiconductor laser device 1 according to embodiment 1.

[0135] 12 and 13 are a plan view and a side view, respectively, showing the configuration of a semiconductor laser device 201 according to this embodiment.

[0136] As shown in FIG. 12, the semiconductor laser device 201 includes a housing 2, a plurality of semiconductor laser elements 10 to 12, a plurality of reflecting mirrors 70 to 72, a condenser lens 90, a plurality of mirror mounting surfaces 80 to 82, submounts 20 to 22, fast-axis collimator lenses 30 to 32, a deflection element 240, parallelizing elements 251 and 252, slow-axis collimator lenses 60 to 62, an optical fiber 4, and current introduction terminals 9a and 9b.

[0137] In this embodiment, the semiconductor laser elements 10 to 12 are disposed on the bottom surface 6a via submounts 20 to 22, respectively.

[0138] The mirror mounting surface 80 is the bottom surface 6a. The semiconductor laser device 201 includes a multi-stage base 208 having mirror mounting surfaces 81 and .

[0139] The deflection element 240 is disposed between the semiconductor laser elements 11, 12 and the reflecting mirrors 71, 72, and provides a component in the height direction from the bottom surface 6a to the propagation direction of the laser beams L1B, L2B. In this embodiment, the deflection element 240 is an optical element having a reflecting surface 240a. In this embodiment, the deflection element 240 is a rectangular prism-shaped optical element whose upper surface is the reflecting surface 240a. As shown in FIG. 13 , the laser beams L1B, L2B are reflected by the reflecting surface 240a of the deflection element 240, thereby providing an upward component from the bottom surface 6a to the propagation direction of the laser beams L1B, L2B, and the laser beams L1C, L2C are emitted from the deflection element 240.

[0140] The plurality of collimating elements 251, 252 are disposed between the deflecting element 240 and the reflecting mirrors 71, 72, respectively, and are deflecting elements that deflect the propagation direction of the laser beams L1C, L2C in a direction parallel to the mirror installation surfaces 81, 82. The plurality of collimating elements 251, 252 are prisms having reflecting surfaces 251a, 252a, respectively. An anti-reflection coating is provided on the entrance surface and exit surface of each of the plurality of collimating elements 251, 252 to reduce reflection. The laser beams L1C, L2C incident on the entrance surfaces of the plurality of collimating elements 251, 252 are reflected by the reflecting surfaces 251a, 252a, respectively, and are emitted from the exit surfaces as laser beams L1D, L2D. In this embodiment, the laser beams L1C and L2C are incident perpendicularly on the incident surfaces of the collimating elements 251 and 252, respectively, and are emitted perpendicularly from the emission surfaces of the collimating elements 251 and 252, respectively.

[0141] As described above, reflective deflection elements may be used as the deflection element 240 and the parallelization elements 251 and 252. The semiconductor laser device 201 according to this embodiment also achieves the same effects as the semiconductor laser device 1 according to the first embodiment.

[0142] (Fourth Embodiment) A semiconductor laser device according to a fourth embodiment will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 1 according to the first embodiment mainly in that the laser light emitted from the semiconductor laser element has a component in the height direction. The following description of the semiconductor laser device according to this embodiment will focus on the differences from the semiconductor laser device 1 according to the first embodiment.

[0143] [4-1. Configuration] The configuration of the semiconductor laser device according to this embodiment will be described with reference to FIGS. 14 and 15. FIG.

[0144] 14 and 15 are a perspective view and a side view, respectively, showing the configuration of a semiconductor laser device 301 according to this embodiment.

[0145] 14, the semiconductor laser device 301 includes a housing 2, a plurality of semiconductor laser elements 10-12, a plurality of reflecting mirrors 70-72, a condenser lens 90, a plurality of mirror mounting surfaces 80-82, submounts 20-22, fast-axis collimator lenses 30-32, parallelizing elements 50-52, slow-axis collimator lenses 60-62, and an optical fiber 4. Note that current introduction terminals and the like are omitted from illustration in FIGS. 14 and 15. Current introduction terminals and the like may also be omitted from illustration in the following drawings.

[0146] The semiconductor laser elements 10-12 according to this embodiment are mounted on a laser mounting surface 307a inclined at an angle of 5 to 20 degrees relative to the bottom surface 6a. As a result, as shown in FIG. 15 , the propagation directions of the laser beams L0A-L2A emitted from the semiconductor laser elements 10-12 are inclined at an angle of 5 to 20 degrees and have a component in the height direction from the bottom surface 6a. Therefore, in this embodiment, the fast axis directions of the laser beams L0A-L2A are not parallel to the X-axis direction. The propagation directions of the laser beams L0A-L2A emitted from the semiconductor laser elements 10-12 have an upward (positive X-axis direction) component. Therefore, in this embodiment, the deflector element 40 and the like used in the first embodiment are not required. This simplifies the configuration of the semiconductor laser device 301.

[0147] Also in this embodiment, similarly to the first embodiment, the plurality of semiconductor laser elements 10 to 12 are arranged on the same plane.

[0148] In this embodiment, the semiconductor laser device 301 includes a multi-stage base 308 having mirror mounting surfaces 80 to 82 and a laser mounting surface 307a.

[0149] Similar to the semiconductor laser device 1 according to the first embodiment, the semiconductor laser device 301 according to the present embodiment also includes a first collimating element (collimating element 51) that is disposed between a first semiconductor laser element (semiconductor laser element 11) and a first reflecting mirror (reflecting mirror 71) and that deflects the propagation direction of the first laser light (laser light L1B) in a direction parallel to the first mirror mounting surface (mirror mounting surface 81), and a second collimating element (collimating element 52) ​​that is disposed between a second semiconductor laser element (semiconductor laser element 12) and a second reflecting mirror (reflecting mirror 72) and that deflects the propagation direction of the second laser light (laser light L2B) by 5 degrees or more and 20 degrees or less in a direction parallel to the second mirror mounting surface (mirror mounting surface 82).

[0150] Furthermore, in the semiconductor laser device 301 according to this embodiment, the first laser light between the first semiconductor laser element and the first collimating element and the second laser light between the second semiconductor laser element and the second collimating element are parallel, and the distance between the second semiconductor laser element and the second collimating element is longer than the distance between the first semiconductor laser element and the first collimating element. The distance in the Z-axis direction of each of the collimating elements 50-52 from the corresponding semiconductor laser element increases as the height of each collimating element from the bottom surface 6a increases. This allows the distance of each of the collimating elements 50-52 from its corresponding semiconductor laser element to vary depending on the height of the installation position of each collimating element. The collimating elements 50-52 are installed near the ends of the mirror installation surfaces 80-82 that are closer to the semiconductor laser elements 10-12, respectively. The collimating elements 50-52 may also be installed in regions on the laser installation surface 307a near the ends of the respective mirror installation surfaces.

[0151] The distance from each semiconductor laser element to each mirror mounting surface increases as the height of each mirror mounting surface from the bottom surface 6a increases. Furthermore, as the height of each mirror mounting surface from the bottom surface 6a increases, the length of each mirror mounting surface in the propagation direction (Z-axis direction) of each laser beam (L0D-L2D, L0E-L2E) decreases. The end of each mirror mounting surface is directly connected to the laser mounting surface 307a. This allows each laser beam to propagate along the laser mounting surface 307a and each mirror mounting surface. This reduces the possibility of each laser beam being blocked by the multi-stage base 308. Furthermore, by arranging each optical element on the laser mounting surface 307a or each mirror mounting surface, each laser beam can be controlled. The laser mounting surface 307a is inclined relative to the bottom surface 6a, and its height from the bottom surface 6a decreases as it moves away from the end of each mirror mounting surface.

[0152] The laser beams L0B to L2B propagate parallel to the laser mounting surface 307a between the semiconductor laser elements 10 to 12 and the collimating elements 50 to 52. Furthermore, the laser beams L0B to L2B propagate parallel to each other between the semiconductor laser elements 10 to 12 and the collimating elements 50 to 52.

[0153] As described above, the semiconductor laser device 301 according to the present embodiment differs from the semiconductor laser device 1 according to the first embodiment in that the propagation direction of each laser beam emitted from each semiconductor laser element has a component in the height direction from the bottom surface 6 a. However, as in the semiconductor laser device 1 according to the first embodiment, the semiconductor laser device 301 according to the present embodiment also differs from the semiconductor laser device 1 according to the first embodiment in that a first distance D1 in the first direction from the light-emitting point 11 e of the semiconductor laser element 11 to the first optical axis A1 of the laser beam L1E incident on the reflecting mirror 71 and a second distance D2 in the first direction from the light-emitting point 11 e of the semiconductor laser element 11 to the second optical axis A2 of the laser beam L2E incident on the reflecting mirror 72 are different from each other, as shown in FIG. 15 . Furthermore, a third distance D3 in the first direction from the light-emitting point 12 e of the semiconductor laser element 12 to the second optical axis A2 of the laser beam L2E incident on the reflecting mirror 72 is greater than the first distance D1.

[0154] As a result, the semiconductor laser device 301 according to this embodiment also achieves the same effects as those of the semiconductor laser device 1 according to the first embodiment.

[0155] [4-2. Modification 1] A semiconductor laser device according to Modification 1 of the present embodiment will be described. The semiconductor laser device according to this modification differs from semiconductor laser device 301 according to embodiment 4 mainly in that the propagation direction of laser beams L0A-L2A emitted from the plurality of semiconductor laser elements 10-12 has a downward component. The semiconductor laser device according to this modification will be described below with reference to FIGS. 16 and 17, focusing on the differences from semiconductor laser device 301 according to embodiment 4.

[0156] 16 and 17 are a perspective view and a side view, respectively, showing the configuration of a semiconductor laser device 301a according to this modification.

[0157] As shown in FIG. 16, the semiconductor laser device 301a includes a housing 2, a plurality of semiconductor laser elements 10 to 12, a plurality of reflecting mirrors 70 to 72, a focusing lens 90, a plurality of mirror mounting surfaces 80a to 82a, submounts 20 to 22, fast-axis collimator lenses 30 to 32, parallelizing elements 50 to 52, slow-axis collimator lenses 60 to 62, and an optical fiber 4.

[0158] In this modification, the semiconductor laser device 301a includes a multi-stage base 308a having mirror mounting surfaces 80a to 82a and a laser mounting surface 307a. The mirror mounting surfaces 80a to 82a have different heights from the bottom surface 6a. Specifically, the mirror mounting surface 81a is lower in height from the bottom surface 6a than the mirror mounting surface 80a, and the mirror mounting surface 82a is lower in height from the bottom surface 6a than the mirror mounting surface 81a.

[0159] The semiconductor laser elements 10-12 according to this modification are mounted on a laser mounting surface 307a that is inclined with respect to the bottom surface 6a. As a result, as shown in FIG. 17, the propagation direction of the laser beams L0A-L2A emitted from the semiconductor laser elements 10-12 has a component in the height direction from the bottom surface 6a. The propagation direction of the laser beams L0A-L2A emitted from the semiconductor laser elements 10-12 has a component in the downward direction. Therefore, in this modification, the deflection element 40 and the like used in the first embodiment and the like are not required. This allows for a simplified configuration of the semiconductor laser device 301a.

[0160] Also in this modification, similarly to the fourth embodiment, the plurality of semiconductor laser elements 10 to 12 are arranged on the same plane.

[0161] The distance in the Z-axis direction from each of the collimating elements 50-52 to the corresponding semiconductor laser element increases as the height from the bottom surface 6a of the installation position of each collimating element decreases. This allows the distance from each semiconductor laser element to each collimating element to vary depending on the height of the installation position of each collimating element. The collimating elements 50-52 are installed near the ends of the mirror installation surfaces 80-82, respectively, that are closer to the semiconductor laser elements 10-12. Note that the collimating elements 50-52 may also be installed in areas on the laser installation surface 307a near the ends of each mirror installation surface.

[0162] The distance from each semiconductor laser element to each mirror mounting surface increases as the height of each mirror mounting surface from the bottom surface 6a decreases. Furthermore, as the height of each mirror mounting surface from the bottom surface 6a decreases, the length of each mirror mounting surface in the propagation direction (Z-axis direction) of each laser beam (L0D-L2D, L0E-L2E) decreases. In other words, the lower the height of each mirror mounting surface 80a-82a from the bottom surface 6a, the shorter the length of the mirror mounting surface in the propagation direction (Z-axis direction) of the laser beam. The end of each mirror mounting surface is directly connected to the laser mounting surface 307a. This allows each laser beam to propagate along the laser mounting surface 307a and each mirror mounting surface. This reduces the blockage of each laser beam by the multi-stage base 308a. Furthermore, by arranging each optical element on the laser mounting surface 307a or each mirror mounting surface, each laser beam can be controlled. The laser mounting surface 307a is inclined with respect to the bottom surface 6a, and the height from the bottom surface 6a increases with increasing distance from the end of each mirror mounting surface.

[0163] The laser beams L0B to L2B propagate parallel to the laser mounting surface 307a between the semiconductor laser elements 10 to 12 and the collimating elements 50 to 52. Furthermore, the laser beams L0B to L2B propagate parallel to each other between the semiconductor laser elements 10 to 12 and the collimating elements 50 to 52.

[0164] The semiconductor laser device 301a according to this modification also has the same effects as those of the semiconductor laser device 301 according to the fourth embodiment.

[0165] [4-3. Modification 2] A semiconductor laser device according to Modification 2 of the present embodiment will be described. The semiconductor laser device according to this modification differs from the semiconductor laser device 301a according to Modification 1 mainly in that the laser mounting surface on which the plurality of semiconductor laser elements 10 to 12 are mounted is parallel to the bottom surface 6a, and the mirror mounting surface is inclined with respect to the bottom surface 6a. The semiconductor laser device according to this modification will be described below with reference to FIG. 18 , focusing on the differences from the semiconductor laser device 301a according to Modification 1.

[0166] FIG. 18 is a side view showing the configuration of a semiconductor laser device 301b according to this modification.

[0167] As shown in FIG. 18, the semiconductor laser device 301b includes a plurality of semiconductor laser elements 10 to 12 (semiconductor laser elements 10 and 11 are not shown), a plurality of reflecting mirrors 70 to 72, a plurality of mirror mounting surfaces 80 a to 82 a, submounts 20 to 22 (submounts 20 and 21 are not shown), fast-axis collimator lenses 30 to 32 (fast-axis collimator lenses 30 and 31 are not shown), collimating elements 50 to 52, and slow-axis collimator lenses 60 to 62.

[0168] The semiconductor laser device 301b includes a laser base 307 having a laser mounting surface 307b, and a multi-stage base 308b having a plurality of mirror mounting surfaces 80a to 82a. The laser base 307 and the multi-stage base 308b may be separate bodies or may be integrated.

[0169] The semiconductor laser device 301 b differs from the semiconductor laser device 301 a according to the first modification in the configuration of the multistage base 308 b and the laser base 307 .

[0170] A semiconductor laser device 301b according to this modification includes a laser base 307 having a laser mounting surface 307b parallel to a lower surface 308ba (or bottom surface 6a) of a multi-stage base 308b. Since the semiconductor laser elements 10 to 12 are mounted on the laser mounting surface 307b, the propagation direction of the laser beams L0A to L2A emitted from the semiconductor laser elements 10 to 12 does not include a component in the height direction from the bottom surface 6a.

[0171] On the other hand, the mirror mounting surfaces 80-82 on which the reflecting mirrors 70-72 are mounted are inclined at an angle of 5 degrees to 20 degrees relative to the lower surface 308ba (or bottom surface 6a) of the multi-stage base 308b. The multiple mirror mounting surfaces 80-82 are parallel to each other. The heights of the ends of the multiple mirror mounting surfaces 80-82 that are closer to each semiconductor laser element from the bottom surface 6a are the same. The height of the ends may be the same as the height of the laser mounting surface 307b.

[0172] The height from the bottom surface 6a of the region of the multistage base 308b between the multiple mirror mounting surfaces 80-82 and the multiple semiconductor laser elements 10-12 is lower than the height of the bottom surface 6a of each light-emitting point of the semiconductor laser elements 10-12. This reduces the possibility of the multistage base 308b blocking each laser beam. In this modification, the positions of the ends of the multistage base 308b close to each semiconductor laser element coincide with the ends of the multiple mirror mounting surfaces 80-82. In other words, there are no components of the multistage base 8 located between each mirror mounting surface and the laser base 307. This reduces the possibility of the multistage base 308b blocking each laser beam, and also reduces the weight of the multistage base 308b.

[0173] In this modification, the collimating elements 50-52 each impart a height component (an upward component in this modification) to the propagation direction of the laser beams L0B-L2B, thereby causing the propagation direction of the laser beams L0D-L2D emitted from the collimating elements 50-52 to be parallel to the mirror mounting surfaces 80-82, respectively. The distance in the Z-axis direction from each of the collimating elements 50-52 to each semiconductor laser element increases as the height from the bottom surface 6a of the installation position of the reflecting mirror corresponding to each collimating element decreases. This allows the distance from each semiconductor laser element to each collimating element to vary depending on the installation position of the reflecting mirror corresponding to each collimating element. The collimating elements 50-52 are installed near the end of the mirror mounting surfaces 80-82, respectively, that is closer to the semiconductor laser elements 10-12.

[0174] The distance from the end of each mirror mounting surface closest to each semiconductor laser element to each semiconductor laser element increases as the height from the bottom surface 6 a of the installation position of each reflecting mirror mounted on each mirror mounting surface decreases. Also, the optical path length of the laser light propagating along each mirror mounting surface decreases as the height from the bottom surface 6 a of the installation position of each reflecting mirror mounted on each mirror mounting surface decreases.

[0175] Each mirror mounting surface may be directly connected to the laser mounting surface 307 a at the end closest to the laser mounting surface 307 a. In this case, the multi-stage base 308 b may be integrated with the laser base 307.

[0176] The laser beams L0B to L2B propagate parallel to the laser mounting surface 307a between the semiconductor laser elements 10 to 12 and the collimating elements 50 to 52. The laser beams L0B to L2B propagate in the positive direction of the Z axis, parallel to the bottom surface 6a. Furthermore, the laser beams L0B to L2B propagate parallel to each other between these two points.

[0177] 18 , in this modification, as in the first embodiment and the like, a first distance D1 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the optical axis (first optical axis A1) of the laser beam L1E incident on the reflecting mirror 71 and a second distance D2 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the optical axis (second optical axis A2) of the laser beam L2E incident on the reflecting mirror 72 are different from each other. A third distance D3 in the first direction from the light-emitting point 12e of the semiconductor laser element 12 to the second optical axis A2 is greater than the first distance D1. In other words, the difference between the height of the light-emitting point 12e of the semiconductor laser element 12 from the bottom surface 6a and the average height of the mirror installation surface 82 from the bottom surface 6a is greater than the difference between the height of the light-emitting point 11e of the semiconductor laser element 11 from the bottom surface 6a and the average height of the mirror installation surface 81 from the bottom surface 6a.

[0178] Therefore, the semiconductor laser device 301b according to this modification also achieves the same effects as those of the first embodiment.

[0179] The semiconductor laser device 301b according to this modification also achieves the same effects as those of the semiconductor laser device 301a according to the first modification.

[0180] Fifth Embodiment A semiconductor laser device according to a fifth embodiment will be described. The semiconductor laser device according to this embodiment differs from the semiconductor laser device 301 according to the fourth embodiment mainly in that the laser light emitted from the semiconductor laser element is perpendicular to the bottom surface 6 a. The following description of the semiconductor laser device according to this embodiment will focus on the differences from the semiconductor laser device 301 according to the fourth embodiment.

[0181] [5-1. Configuration] The configuration of the semiconductor laser device according to this embodiment will be described with reference to FIGS. 19 and 20. FIG.

[0182] 19 and 20 are a perspective view and a side view, respectively, showing the configuration of a semiconductor laser device 401 according to this embodiment.

[0183] As shown in FIG. 19, the semiconductor laser device 401 includes a housing 2, a plurality of semiconductor laser elements 10 to 12, a plurality of reflecting mirrors 70 to 72, a focusing lens 90, a plurality of mirror mounting surfaces 80 to 82, submounts 20 to 22, fast-axis collimator lenses 30 to 32, parallelizing elements 450 to 452, slow-axis collimator lenses 60 to 62, and an optical fiber 4.

[0184] The semiconductor laser device 401 includes a laser mounting surface 407a on which a plurality of semiconductor laser elements 10-12 are mounted, and a multi-stage base 408 having a plurality of mirror mounting surfaces 80-82. The laser mounting surface 407a, the plurality of mirror mounting surfaces 80-82, and the bottom surface 6a intersect perpendicularly. The plurality of semiconductor laser elements 10-12 according to this embodiment are mounted on a laser mounting surface 407b that intersects perpendicularly with the bottom surface 6a and the plurality of mirror mounting surfaces 80-82. As a result, the propagation direction of the laser beams L0A-L2A emitted from the plurality of semiconductor laser elements 10-12 includes a component in the height direction from the bottom surface 6a. The laser beams L0A-L2A emitted by the plurality of semiconductor laser elements 10-12 propagate upward (positive in the X-axis direction). The collimating elements 450-452 respectively deflect the laser beams L0B-L2B emitted by the plurality of semiconductor laser elements 10-12 (laser beams L0B-L2B obtained by collimating the laser beams L0A-L2A emitted by the plurality of semiconductor laser elements 10-12 by the fast-axis collimator lenses 30-32) by 90 degrees. The collimating elements 450-452 respectively deflect the laser beams L0B-L2B in the positive direction of the Z axis. In this embodiment, the collimating elements 450-452 are reflective deflection elements formed by triangular prisms having a reflective surface and a right-angled triangular base. The laser beams L0B-L2B incident on the entrance surfaces of the collimating elements 450-452, respectively, are reflected by the reflective surfaces of the collimating elements 450-452 and are emitted as laser beams L0D-L2D from the reflective surfaces via the exit surfaces. That is, the laser beams L0D to L2D are reflected light beams of the laser beams L0B to L2B reflected by the reflecting surfaces of the collimating elements 450 to 452, respectively. In this embodiment, the laser beams L0B to L2B are incident perpendicularly on the incident surfaces of the collimating elements 450 to 452, respectively, and the laser beams L0D to L2D are emitted perpendicularly from the exit surfaces of the collimating elements 450 to 452.

[0185] The collimating elements 450-452 are installed outside the corner where the laser mounting surface 407a and the multiple mirror mounting surfaces 80-82 intersect perpendicularly, on a line extending to the emission side of the semiconductor laser elements 10-12, and at the same height as the reflecting mirrors 70-72. In this embodiment, the collimating elements 450-452 are installed on the mirror mounting surfaces 80-82, respectively. Each collimating element is installed so as to protrude from its corresponding mirror mounting surface in a direction parallel to the corresponding mirror mounting surface, approaching the optical axis of the laser beams L0B-L2B. This allows each laser beam to be incident on the reflecting surface of each collimating element. The reflecting surface of each collimating element is arranged at an angle relative to the corresponding mirror mounting surface and the laser mounting surface 407a. In this embodiment, the angle of inclination of the reflecting surface of each collimating element relative to the corresponding mirror mounting surface and the laser mounting surface 407a is 45 degrees. The collimating elements 450 to 452 may be reflective mirrors and may be installed on a surface other than the mirror installation surface. For example, the collimating elements 450 to 452 may be installed on the laser installation surface 407a.

[0186] 20 , in the semiconductor laser device 401 according to the present embodiment, a first distance D1 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the optical axis (first optical axis A1) of the laser beam L1E incident on the reflecting mirror 71 and a second distance D2 in the first direction from the light-emitting point 11e of the semiconductor laser element 11 to the optical axis (second optical axis A2) of the laser beam L2E incident on the reflecting mirror 72 are different from each other. A third distance D3 in the first direction from the light-emitting point 12e of the semiconductor laser element 12 to the second optical axis A2 is greater than the first distance D1. In this embodiment, since the laser beams L1A, L2A, L1B, and L2B propagate in a direction perpendicular to the first optical axis A1 and the second optical axis A2, the first distance D1 is equal to the sum of the optical path length of the laser beam L1A and the optical path length of the laser beam L1B (i.e., the optical path length from the light-emitting point 11e to the intersection of the reflecting surface of the collimating element 451 and the first optical axis A1). Moreover, the second distance D2 and the third distance D3 are equal to the sum of the optical path length of the laser beam L2A and the optical path length of the laser beam L2B (i.e., the optical path length from the light-emitting point 12e to the intersection of the reflecting surface of the collimating element 452 and the second optical axis A2).

[0187] Furthermore, the semiconductor laser device 401 according to this embodiment also achieves the same effects as those of the semiconductor laser device 301 according to the fourth embodiment.

[0188] Furthermore, in this embodiment, the optical axis of the laser light is deflected by 90 degrees by each collimating element, thereby making it possible to reduce the size of the semiconductor laser device 401 in the Z-axis direction.

[0189] [5-2. Modifications] A semiconductor laser device according to a modification of the present embodiment will be described. The semiconductor laser device according to this modification differs from the semiconductor laser device 401 according to the fifth embodiment mainly in that the propagation direction of the laser beams L0A to L2A emitted from the plurality of semiconductor laser elements 10 to 12 is downward. The semiconductor laser device according to this modification will be described below with reference to FIG. 21 , focusing on the differences from the semiconductor laser device 401 according to the fifth embodiment.

[0190] FIG. 21 is a perspective view showing the configuration of a semiconductor laser device 401a according to this modification.

[0191] As shown in FIG. 21, the semiconductor laser device 401a includes a housing 2, a plurality of semiconductor laser elements 10 to 12, a plurality of reflecting mirrors 70 to 72, a focusing lens 90, a plurality of mirror mounting surfaces 80 to 82, submounts 20 to 22, fast-axis collimator lenses 30 to 32, parallelizing elements 50 to 52, slow-axis collimator lenses 60 to 62, and an optical fiber 4.

[0192] The semiconductor laser device 401a includes a laser mounting surface 407b on which multiple semiconductor laser elements 10-12 are mounted, and a multi-stage base 408a having multiple mirror mounting surfaces 80-82. The multi-stage base 408a has a lower surface 408ba and mirror mounting surfaces 80-82 that are parallel to and face the lower surface 408ba. The mirror mounting surfaces 80-82 have different heights from the bottom surface 6a, with the mirror mounting surfaces 82, 81, and 80 having increasing heights from the bottom surface in this order. The laser mounting surface 407b perpendicularly intersects with the multiple mirror mounting surfaces 80-82 and the bottom surface 6a. The laser mounting surface 407b extends upward from the ends of the mirror mounting surfaces 80-82 that are closer to the semiconductor laser elements 10-12, in the direction opposite to the lower surface 408ba. In a cross section viewed from the Y-axis direction, the laser mounting surface 407b and the mirror mounting surfaces 80-82 form an L-shape, and the multi-step base 408a has an L-shaped recessed portion. In other words, the multi-step base 408a has a stepped upper surface including the mirror mounting surfaces 80-82, a first plate-like portion extending along the bottom surface 6a, and a second plate-like portion connected to the first plate-like portion, including the laser mounting surface 407b, and erected on the bottom surface 6a. The multiple semiconductor laser elements 10-12 according to this embodiment are mounted on the laser mounting surface 407b, which perpendicularly intersects with the bottom surface 6a and the multiple mirror mounting surfaces 80-82. As a result, the propagation direction of laser beams L0A-L2A (not shown in FIG. 21 ) emitted from the multiple semiconductor laser elements 10-12 includes a component in the height direction from the bottom surface 6a. The laser beams L0A to L2A emitted by the semiconductor laser elements 10 to 12 propagate downward (negative direction in the X-axis direction). The collimating elements 450 to 452 respectively deflect the laser beams L0B to L2B emitted by the semiconductor laser elements 10 to 12 (laser beams L0B to L2B obtained by collimating the laser beams L0A to L2A emitted by the semiconductor laser elements 10 to 12 by the fast-axis collimator lenses 30 to 32) by 90 degrees. The collimating elements 450 to 452 respectively deflect the laser beams L0B to L2B in the positive direction in the Z-axis direction. The collimating elements 450 to 452 are reflective deflection elements having a reflective surface. The collimating elements 450 to 452 are installed near the ends of the mirror installation surfaces 80 to 82 that are closer to the semiconductor laser elements 10 to 12.The collimating elements 450-452 may be reflective mirrors.

[0193] The semiconductor laser device 401a according to this modification also has the same effects as those of the semiconductor laser device 401 according to the fifth embodiment.

[0194] (Other Embodiments) While the semiconductor laser device according to the present disclosure has been described above based on the embodiments and modifications thereof, the present disclosure is not limited to these embodiments and modifications thereof. As long as they do not deviate from the gist of the present disclosure, various modifications conceivable by a person skilled in the art to the embodiments and other forms constructed by combining some of the components of the embodiments and modifications thereof are also included in the scope of the present disclosure.

[0195] For example, in each embodiment, instead of arranging each SLOW-axis collimator lens between each collimating element and each reflecting mirror, each SLOW-axis collimator lens may be arranged between each semiconductor laser element (or each FAST-axis collimator lens) and each collimating element, or between each semiconductor laser element (or each FAST-axis collimator lens) and each deflection element. An example in which the above-described modifications are applied to the semiconductor laser device 1 according to the first embodiment will be described below with reference to FIGS. 22 and 23 . FIG. 22 is a perspective view showing the configuration of a semiconductor laser device 1c according to a third modification of the first embodiment. FIG. 23 is a perspective view showing the configuration of a semiconductor laser device 1d according to a fourth modification of the first embodiment.

[0196] 22 , the semiconductor laser device 1c according to the third modification differs from the semiconductor laser device 1 according to the first embodiment in the configuration and arrangement of a slow-axis collimator lens 60c. The slow-axis collimator lens 60c according to the third modification is arranged between the plurality of collimating elements 51 to 55 and the plurality of semiconductor laser elements 11 to 15, and between the reflecting mirror 70 and the semiconductor laser element 10. More specifically, the slow-axis collimator lens 60c is arranged between the deflection element 40 and the plurality of fast-axis collimator lenses 31 to 35, and between the reflecting mirror 70 and the fast-axis collimator lens 30.

[0197] The slow-axis collimator lens 60c has a configuration in which multiple slow-axis collimator lenses 60 to 65 arranged in the Y-axis direction are integrated. In the third modification, the slow-axis collimator lens 60c corresponding to multiple laser beams is disposed in the region between the deflection element 40 and the multiple semiconductor laser elements 10 to 15, that is, in the region where the multiple laser beams are in the same plane, thereby making it possible to arrange the multiple slow-axis collimator lenses 60 to 65 on the same plane. Therefore, in the third modification, the multiple slow-axis collimator lenses 60 to 65 can be easily integrated. Furthermore, since the multiple slow-axis collimator lenses 60 to 65 are integrated, the installation work of the slow-axis collimator lens 60c can be facilitated.

[0198] Furthermore, in Modification 3, since each slow-axis collimator lens is not disposed on each mirror installation surface, it is possible to shorten the length of each mirror installation surface in the Z-axis direction, which in turn allows the dimensions of multi-stage base 8 to be reduced, thereby making it possible to reduce the weight of multi-stage base 8.

[0199] The semiconductor laser device 1d according to the modified example 4 shown in FIG. 23 differs from the semiconductor laser device 1c according to the modified example 3 mainly in that it has a plurality of deflection elements 41 to 45 instead of the deflection element 40, and in the arrangement of the plurality of deflection elements 41 to 45 and the plurality of parallelization elements 51 to 55.

[0200] The plurality of deflection elements 41 to 45 according to the fourth modification are respectively disposed between the slow-axis collimator lens 60c and the plurality of parallelizing elements 51 to 55. In the fourth modification, the slow-axis collimator lens 60c and the plurality of deflection elements 41 to 45 are disposed on the laser base 7.

[0201] The distance in the Z-axis direction from each deflection element to each semiconductor laser element decreases as the height from the bottom surface 6a of the corresponding collimating element and each reflecting mirror increases. Meanwhile, the position of each collimating element in the Z-axis direction is the same. In other words, the distance in the Z-axis direction between each deflection element and each collimating element increases as the height from the bottom surface 6a of each collimating element increases. This allows each laser beam to propagate to each of the multiple collimating elements installed at different heights. Note that, in the fourth modification, the propagation directions of the multiple laser beams propagating between the multiple deflection elements 41 to 45 and the multiple collimating elements 51 to 55 are parallel to each other and inclined with respect to the bottom surface 6a.

[0202] The lengths of the multiple mirror mounting surfaces in the Z-axis direction according to Modification 4 may be equal. This allows the edges of the multiple mirror mounting surfaces to be formed on the same plane, which facilitates the manufacture of the multi-stage base 8d having multiple mirror mounting surfaces. Each collimating element is disposed near the end of each mirror mounting surface that is closer to each semiconductor laser element.

[0203] The semiconductor laser devices according to the third and fourth modifications of the first embodiment as described above also have the same effects as those of the semiconductor laser device 1 according to the first embodiment.

[0204] In addition, in the fourth embodiment and the first and second modifications of the fourth embodiment, instead of disposing the collimating element on the mirror mounting surface, the collimating element may be disposed on the laser mounting surface that is inclined with respect to the bottom surface. In this case, the collimating element is disposed near the end of the laser mounting surface that is closer to the reflecting mirror.

[0205] Furthermore, the above-described embodiments can be modified, substituted, added, omitted, and the like in various ways within the scope of the claims or their equivalents.

[0206] The semiconductor laser device according to the present disclosure is particularly useful as a high-brightness, high-power laser light source, such as a laser light source for processing, a laser light source for displays, or a laser light source for medical use.

[0207] DESCRIPTION OF SYMBOLS 1, 1a, 1b, 1c, 1d, 101, 201, 301, 301a, 301b, 401, 401a Semiconductor laser device 2 Housing 3 Side wall 4 Optical fiber 6 Bottom 6a Bottom surface 7, 307 Laser base 7a, 307a, 307b, 407a, 407b Laser installation surface 8, 8a, 8b, 8d, 108, 208, 308, 308a, 308b, 408, 408a Multi-stage base 8ba, 308ba, 408ba Bottom surface 9a, 9b Current input terminal 9c Wiring member 10, 11, 12, 13, 14, 15 Semiconductor laser element 10e, 11e, 12e, 13e, 14e, 15e Light-emitting point 20, 21, 22, 23, 24, 25, 120 Submount 30, 31, 32, 33, 34, 35, 130 FAST axis collimator lens 40, 40a, 40b, 41, 42, 43, 44, 45, 240 Deflection element 50, 51, 51a, 52, 52a, 53, 53a, 54, 54a, 55, 251, 252, 450, 451, 452 Parallelization element 60, 60c, 61, 62, 63, 64, 65 SLOW axis collimator lens 70, 71, 72, 73, 74, 75 Reflection mirror 80, 80a, 81, 81a, 82, 82a, 83, 83a, 84, 84a, 85 Mirror installation surface 90 REFERENCE SIGNS LIST 107 Airtight package 110 Semiconductor laser array 117 Light-transmitting window 126, 127, 128, 129 Metal films 240a, 251a, 252a Reflecting surface A1 First optical axis A2 Second optical axis D1 First distance D2 Second distance D3 Third distance D4 Fourth distance L0A, L0B, L0D, L0E, L0F, L1A, L1B, L1C, L1D, L1E, L1F, L2A, L2B, L2C, L2D, L2E, L2F, L3A, L3B, L3C, L3D, L3E, L3F, L4A, L4B, L4C, L4D, L4E, L4F, L5A, L5B, L5C, L5D, L5E, L5F Laser light P01 Opening P20 Frame P21 First package P30 Package bottom P31 Anode lead-out electrode P32 Anode electrode P34 Cathode lead-out electrode P35 Cathode electrode W Metal wire

Claims

1. A semiconductor laser device, comprising: a housing having a bottom surface; a first semiconductor laser element and a second semiconductor laser element disposed within the housing; a first reflection mirror that reflects first laser light emitted from the first semiconductor laser element; a second reflection mirror that reflects second laser light emitted from the second semiconductor laser element; a condenser lens that condenses the first laser light reflected by the first reflection mirror and the second laser light reflected by the second reflection mirror; a first mirror installation surface on which the first reflection mirror is installed; a second mirror installation surface on which the second reflection mirror is installed; the first mirror installation surface and the second mirror installation surface are parallel to each other; the first mirror installation surface and the second mirror installation surface are not on the same plane; the first semiconductor laser element has a first light emission point from which the first laser light is emitted; the second semiconductor laser element has a second light emission point from which the second laser light is emitted; an optical axis of the first laser light incident on the first reflection mirror is defined as a first optical axis; an optical axis of the second laser light incident on the second reflection mirror is defined as a second optical axis; when a direction perpendicular to the first optical axis passing through the first light emission point is defined as a first direction, a first distance in the first direction from the first light emission point to the first optical axis and a second distance in the first direction from the first light emission point to the second optical axis are different from each other; a third distance in the first direction from the second light emission point to the second optical axis is greater than the first distance; the semiconductor laser device further comprises: a first deflection element disposed between the first semiconductor laser element and the first reflection mirror, and providing a component in the first direction in a propagation direction of the first laser light; A first collimating element disposed between the first deflecting element and the first reflecting mirror, for deflecting the propagation direction of the first laser beam in a direction parallel to the first mirror installation surface. A second deflecting element disposed between the second semiconductor laser element and the second reflecting mirror, for imparting a component in the first direction to the propagation direction of the second laser beam. Further comprising a second collimating element disposed between the second deflecting element and the second reflecting mirror, for deflecting the propagation direction of the second laser beam in a direction parallel to the second mirror installation surface. The first laser beam between the first deflecting element and the first collimating element is parallel to the second laser beam between the second deflecting element and the second collimating element. The distance between the second deflecting element and the second collimating element is longer than the distance between the first deflecting element and the first collimating element. The first deflecting element and the second deflecting element are integrated. A semiconductor laser device.

2. A housing having a bottom surface. A first semiconductor laser element and a second semiconductor laser element disposed within the housing. A first reflecting mirror for reflecting the first laser beam emitted from the first semiconductor laser element. A second reflecting mirror for reflecting the second laser beam emitted from the second semiconductor laser element. A condensing lens for condensing the first laser beam reflected by the first reflecting mirror and the second laser beam reflected by the second reflecting mirror. A first mirror installation surface on which the first reflecting mirror is installed. And a second mirror installation surface on which the second reflecting mirror is installed. The first mirror installation surface and the second mirror installation surface are parallel to each other. The first mirror installation surface and the second mirror installation surface are not on the same plane. The first semiconductor laser element has a first light emitting point from which the first laser beam is emitted. The second semiconductor laser element has a second light-emitting point from which the second laser light is emitted. Taking the optical axis of the first laser light incident on the first reflection mirror as the first optical axis, Taking the optical axis of the second laser light incident on the second reflection mirror as the second optical axis, When the first direction is the direction perpendicular to the first optical axis passing through the first light-emitting point, The first distance in the first direction from the first light-emitting point to the first optical axis and the second distance in the first direction from the first light-emitting point to the second optical axis are different from each other. The third distance in the first direction from the second light-emitting point to the second optical axis is greater than the first distance. The first laser light emitted from the first reflection mirror and the second laser light emitted from the second reflection mirror have parallel propagation directions, and the positions in the FAST axis direction of the first laser light emitted from the first reflection mirror do not overlap, and the positions in the SLOW axis direction of the first laser light emitted from the first reflection mirror overlap. Semiconductor laser device.

3. A first deflection element disposed between the first semiconductor laser element and the first reflection mirror and giving a component in the first direction to the propagation direction of the first laser light, A first parallelization element disposed between the first deflection element and the first reflection mirror and deflecting the propagation direction of the first laser light in a direction parallel to the first mirror installation surface, A second deflection element disposed between the second semiconductor laser element and the second reflection mirror and giving a component in the first direction to the propagation direction of the second laser light, And a second parallelization element disposed between the second deflection element and the second reflection mirror and deflecting the propagation direction of the second laser light in a direction parallel to the second mirror installation surface. The semiconductor laser device according to claim 2.

4. A semiconductor laser device, A housing having a bottom surface, The first semiconductor laser element and the second semiconductor laser element disposed in the housing, A first reflection mirror that reflects the first laser light emitted from the first semiconductor laser element, A second reflection mirror that reflects the second laser light emitted from the second semiconductor laser element, A condenser lens that condenses the first laser light reflected by the first reflection mirror and the second laser light reflected by the second reflection mirror, A first collimating element disposed between the first semiconductor laser element and the first reflection mirror, and deflecting the propagation direction of the first laser light, A second collimating element disposed between the second semiconductor laser element and the second reflection mirror, and deflecting the propagation direction of the second laser light, The first semiconductor laser element has a first light emitting point from which the first laser light is emitted, The second semiconductor laser element has a second light emitting point from which the second laser light is emitted, The optical axis of the first laser light incident on the first collimating element and the optical axis of the second laser light incident on the second collimating element are parallel, The optical axis of the first laser light incident on the first reflection mirror and the optical axis of the second laser light incident on the second reflection mirror are parallel, The optical axis of the first laser light incident on the first reflection mirror is inclined with respect to the optical axis of the first laser light incident on the first collimating element, The optical axis of the first laser light incident on the first reflection mirror is defined as the first optical axis, The optical axis of the second laser light incident on the second reflection mirror is defined as the second optical axis, When the direction perpendicular to the first optical axis passing through the first light emitting point is defined as the first direction, The first distance in the first direction from the first light emitting point to the first optical axis and the second distance in the first direction from the first light emitting point to the second optical axis are different from each other, The third distance in the first direction from the second light emitting point to the second optical axis is larger than the first distance, The semiconductor laser device is A first deflection element disposed between the first semiconductor laser element and the first collimation element, and giving a component in the first direction to the propagation direction of the first laser beam Further comprising a second deflection element disposed between the second semiconductor laser element and the second collimation element, and giving a component in the first direction to the propagation direction of the second laser beam The first laser beam between the first deflection element and the first collimation element and the second laser beam between the second deflection element and the second collimation element are parallel The distance between the second deflection element and the second collimation element is longer than the distance between the first deflection element and the first collimation element Semiconductor laser device.

5. A first mirror installation surface on which the first reflection mirror is installed, And a second mirror installation surface on which the second reflection mirror is installed The semiconductor laser device according to claim 4.

6. The first collimation element is installed on the first mirror installation surface, The second collimation element is installed on the second mirror installation surface The semiconductor laser device according to any one of claims 1, 3, and 5.

7. Each of the first deflection element, the first collimation element, the second deflection element, and the second collimation element is a transmissive deflection element The semiconductor laser device according to any one of claims 1, 3, and 4.

8. The transmissive deflection element is a prism having an incident surface and an exit surface, The incident surface and the exit surface are not parallel The semiconductor laser device according to claim 7.

9. The FAST axis direction of each of the first semiconductor laser element and the second semiconductor laser element is the height direction from the bottom surface The semiconductor laser device according to any one of claims 1 to 5.

10. The propagation directions of the laser lights emitted from each of the first semiconductor laser element and the second semiconductor laser element have components in the height direction from the bottom surface. The semiconductor laser device according to claim 2.

11. A semiconductor laser device, comprising: A housing having a bottom surface; A first semiconductor laser element and a second semiconductor laser element disposed in the housing; A first reflecting mirror that reflects the first laser light emitted from the first semiconductor laser element; A second reflecting mirror that reflects the second laser light emitted from the second semiconductor laser element; A condenser lens that condenses the first laser light reflected by the first reflecting mirror and the second laser light reflected by the second reflecting mirror; A first mirror installation surface on which the first reflecting mirror is installed; And a second mirror installation surface on which the second reflecting mirror is installed, The first mirror installation surface and the second mirror installation surface are parallel to each other. The first mirror installation surface and the second mirror installation surface are not on the same plane. The first semiconductor laser element has a first light-emitting point from which the first laser light is emitted. The second semiconductor laser element has a second light-emitting point from which the second laser light is emitted. Taking the optical axis of the first laser light incident on the first reflecting mirror as the first optical axis, Taking the optical axis of the second laser light incident on the second reflecting mirror as the second optical axis, When a direction perpendicular to the first optical axis passing through the first light-emitting point is defined as the first direction, A first distance in the first direction from the first light-emitting point to the first optical axis and a second distance in the first direction from the first light-emitting point to the second optical axis are different from each other. The third distance in the first direction from the second light-emitting point to the second optical axis is greater than the first distance. The semiconductor laser device A first parallelizing element disposed between the first semiconductor laser element and the first reflection mirror, and deflecting the propagation direction of the first laser light in a direction parallel to the first mirror installation surface; Further comprising a second parallelizing element disposed between the second semiconductor laser element and the second reflection mirror, and deflecting the propagation direction of the second laser light in a direction parallel to the second mirror installation surface. Semiconductor laser device.

12. The first laser light between the first semiconductor laser element and the first parallelizing element and the second laser light between the second semiconductor laser element and the second parallelizing element are parallel, The distance between the second semiconductor laser element and the second parallelizing element is longer than the distance between the first semiconductor laser element and the first parallelizing element. The semiconductor laser device according to claim 11.

13. Each of the first parallelizing element and the second parallelizing element deflects the first laser light and the second laser light by 90 degrees. The semiconductor laser device according to claim 11 or 12.

14. The first parallelizing element is installed on the first mirror installation surface, The second parallelizing element is installed on the second mirror installation surface. The semiconductor laser device according to claim 11 or 12.

15. Each of the first parallelizing element and the second parallelizing element is a transmissive deflection element. The semiconductor laser device according to claim 11 or 12.

16. The transmissive deflection element is a prism having an incident surface and an exit surface, The incident surface and the exit surface are not parallel. The semiconductor laser device according to claim 15.

17. Comprising a FAST axis collimator lens disposed between the first semiconductor laser element and the first collimating element. The semiconductor laser device according to any one of claims 1, 3 to 5, 11, and 12.

18. Comprising a SLOW axis collimator lens disposed between the FAST axis collimator lens and the first reflecting mirror. The semiconductor laser device according to claim 17.

19. The distance in the first direction from the first light emitting point to the second light emitting point is smaller than the distance in the first direction from the first optical axis to the second optical axis. The semiconductor laser device according to any one of claims 1 to 5, 10 to 12.

20. The bottom surface is flat. The semiconductor laser device according to any one of claims 1 to 5, 10 to 12.

21. The first semiconductor laser element and the second semiconductor laser element are installed in the same plane. The semiconductor laser device according to any one of claims 1 to 5, 10 to 12.

22. Comprising an airtight package for airtightly sealing at least one of the first semiconductor laser element and the second semiconductor laser element. The semiconductor laser device according to any one of claims 1 to 5, 10 to 12.

23. Comprising a single airtight package for airtightly sealing the first semiconductor laser element and the second semiconductor laser element. The semiconductor laser device according to any one of claims 1 to 5, 10 to 12.

24. The first semiconductor laser element and the second semiconductor laser element are included in a single element. The semiconductor laser device according to any one of claims 1 to 5 and 10 to 12.