Light source module and manufacturing method for light source module

Abstract

To provide a light source module that can adjust the position accurately.SOLUTION: A light source module includes a semiconductor laser element 200 that emits first laser light L1001, and an optical member 1600 including a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 includes an active layer. The first cylindrical lens 110, upon the incidence of the first laser light L1001, changes the divergence angle of the first laser light L1001 in a fast axis direction. The first laser light L1001 emitted from the first cylindrical lens 110 enters an incidence surface of an optical element. By fixing the first installation plane to a first installation reception plane, the first cylindrical lens 110 is fixed. A bus line of the first cylindrical lens 110 is inclined to the first installation reception plane. The angle θ between the bus line and the active layer satisfies |θ|<22.5°.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a light source module and a method for manufacturing the light source module. [Background technology]

[0002] Patent Document 1 discloses a solid-state laser device (light source module) that includes a semiconductor laser element, an optical system (lens) that focuses the laser light emitted from the semiconductor laser element, and a solid-state laser medium (optical element) into which the laser light emitted from the optical system is incident. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-012931 Summary of the Invention [Problem to be solved by the invention]

[0004] In a light source module including the solid-state laser device disclosed in Patent Document 1, laser light can generally be efficiently emitted by increasing the overlap between the excitation region of the excitation laser light and the resonator mode region in the solid-state laser medium. In order to increase the overlap between the excitation region of the excitation laser light and the resonator mode region in the solid-state laser medium, the positions of the components included in the light source module need to be adjusted with high precision.

[0005] Therefore, an object of the present disclosure is to provide a light source module or the like that can be precisely positioned. [Means for solving the problem]

[0006] In order to achieve the above object, a light source module according to one embodiment of the present disclosure includes a semiconductor laser element that emits a first laser light, and an optical element having a first cylindrical lens and a first installation plane, wherein the semiconductor laser element has an active layer, the first cylindrical lens receives the first laser light and changes the divergence angle of the first laser light in the fast axis direction, the first laser light emitted from the first cylindrical lens is incident on an incident surface of an optical element, the first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens, the generatrix of the first cylindrical lens is inclined with respect to the first installation plane, and the angle θ between the generatrix and the active layer is |θ|<22.5°.

[0007] Furthermore, a light source module according to one embodiment of the present disclosure includes a semiconductor laser element that emits a first laser light, and an optical element having a first cylindrical lens and a first installation plane, wherein the semiconductor laser element has an active layer, the first cylindrical lens receives the first laser light and changes the divergence angle of the first laser light in the fast axis direction, the first laser light emitted from the first cylindrical lens is incident on an incident surface of an optical element, the first installation plane is fixed to a first installation plane so that the first cylindrical lens is fixed, a generatrix of the first cylindrical lens is inclined with respect to the first installation plane, and an angle θ between the generatrix and the active layer is |θ|<22.5°.

[0008] Furthermore, a method for manufacturing a light source module according to an aspect of the present disclosure is a method for manufacturing a light source module, the light source module including a semiconductor laser element that emits a first laser beam, and an optical member having a first cylindrical lens, an optical element, and a first installation plane, the semiconductor laser element having an active layer, the first cylindrical lens having an incident surface on which the first laser beam is incident and which changes a divergence angle of the first laser beam in a fast axis direction, the first laser beam emitted from the first cylindrical lens being incident on an incident surface of the optical element, and the first installation plane being fixed to a first installation plane, The manufacturing method includes a first placement step of placing the optical element on the first installation plane so that the generatrix of the first cylindrical lens is inclined with respect to the first installation plane; a first alignment step of making the first laser light emitted from the semiconductor laser element incident on the first cylindrical lens and moving the placed optical element in two mutually perpendicular directions parallel to the first installation plane; and a first fixing step of fixing the first installation plane of the moved optical element to the first installation plane, wherein in the first placement step, the angle θ between the generatrix and the active layer is |θ|<22.5°. [Effects of the Invention]

[0009] According to the present disclosure, it is possible to provide a light source module or the like that can be adjusted in position with high precision. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing the overall configuration of a light source module according to the first embodiment. [Figure 2] FIG. 2 is a cross-sectional view showing a cross section of the light source module taken along line II-II in FIG. [Figure 3] 3 is a cross-sectional view showing a cross section of the light source module taken along line III-III in FIG. [Figure 4] FIG. 4 is an enlarged perspective view of the semiconductor laser device according to the first embodiment. [Figure 5] FIG. 5 is a perspective view of the optical member according to the first embodiment. [Figure 6] FIG. 6 is a side view and a cross-sectional view of the light source module according to the first embodiment. [Figure 7] FIG. 7 is a first example of another side view and a cross-sectional view of the light source module according to the first embodiment. [Figure 8] FIG. 8 shows a second example of a side view and a cross-sectional view of the light source module according to the first embodiment. [Figure 9] FIG. 9 is a top view of the light source module according to the first embodiment. [Figure 10] FIG. 10 is another example of a top view of the light source module according to the first embodiment. [Figure 11] FIG. 11 is a diagram showing the relationship between the angle θ and the movement amount Δz of the first cylindrical lens in the z-axis direction and the movement amount Δx of the first cylindrical lens in the x-axis direction according to the first embodiment. [Figure 12] FIG. 12 is a front view showing an example before the optical member is moved in the x-axis direction in the first alignment step according to the first embodiment. [Figure 13] FIG. 13 is a front view showing an example after the optical member has been moved in the x-axis direction in the first alignment step according to the first embodiment. [Figure 14] FIG. 14 is a diagram showing the relationship between Δx, which is the amount of movement in the x-axis direction, and Δz, which is the amount of movement in the z-axis direction, when the angle θ according to the first embodiment is a specific angle. [Figure 15] FIG. 15 is a perspective view showing a configuration of a light source module according to Modification 1 of Embodiment 1. As shown in FIG. [Figure 16] 16 is a cross-sectional view showing a cut surface of the light source module taken along line XVI-XVI in FIG. [Figure 17] FIG. 17 is a perspective view showing a configuration of a light source module according to Modification 2 of Embodiment 1. As shown in FIG. [Figure 18A] 18A is a cross-sectional view showing a cross section of the light source module taken along line XVIIIA-XVIIIA in FIG. [Figure 18B] FIG. 18B is a perspective view showing the configuration of a light source module according to another example of the second modification of the first embodiment. [Figure 19] FIG. 19 is a cross-sectional view showing the configuration of a light source module according to Modification 3 of Embodiment 1. As shown in FIG. [Figure 20] FIG. 20 is a cross-sectional view illustrating another example of the configuration of the light source module according to the third modification of the first embodiment. [Figure 21] FIG. 21 is a perspective view showing the configuration of a light source module according to the fourth modification of the first embodiment. [Figure 22] 22 is a cross-sectional view showing a cross section of the light source module taken along line XXII-XXII in FIG. [Figure 23] FIG. 23 is a perspective view showing the configuration of a light source module according to the second embodiment. [Figure 24] 24 is a cross-sectional view showing a cross section of the light source module taken along line XXIV-XXIV in FIG. [Figure 25] 25 is a cross-sectional view showing a cross section of the light source module taken along line XXV-XXV in FIG. [Figure 26] FIG. 26 is another example of a cross-sectional view showing a cross section of the light source module taken along line XXIV-XXIV in FIG. [Figure 27] FIG. 27 is a cross-sectional view of the light source module shown in FIG. 26 after a first alignment step has been performed. [Figure 28] FIG. 28 is a perspective view showing a configuration of a part of a light source module according to Modification 1 of Embodiment 2. As shown in FIG. [Figure 29A] FIG. 29A is a perspective view showing a configuration of a part of a light source module according to Modification 2 of Embodiment 2. FIG. [Figure 29B] FIG. 29B is a perspective view showing a configuration of a part of a light source module according to Modification 3 of Embodiment 2. FIG. [Figure 29C] FIG. 29C is a perspective view showing the configuration of a light source module according to the fourth modification of the second embodiment. [Figure 29D]FIG. 29D is a cross-sectional view showing a cut surface of the laser crystal and the first support member taken along line XXIXD-XXIXD in FIG. 29C. [Figure 30] FIG. 30 is a perspective view showing the configuration of a light source module according to the third embodiment. [Figure 31] 31 is a cross-sectional view showing a cross section of the light source module taken along line XXXI-XXXI in FIG. [Figure 32] FIG. 32 is a side view of the light source module according to the third embodiment. [Figure 33] FIG. 33 is another first example of a side view of the light source module according to the third embodiment. [Figure 34] FIG. 34 is a second other example of a side view of the light source module according to the third embodiment. [Figure 35] FIG. 35 is a perspective view showing a configuration of a light source module according to a first modification of the third embodiment. [Figure 36] FIG. 36 is a perspective view showing the configuration of a module package according to a first modification of the third embodiment. [Figure 37] FIG. 37 is a perspective view showing the configuration of a light source module according to the fourth embodiment. [Figure 38A] FIG. 38A is a side view showing the configuration of a light source module according to the fifth embodiment. [Figure 38B] FIG. 38B is a top view showing the configuration of the light source module according to the fifth embodiment. [Figure 39] FIG. 39 is another first example of a side view of the light source module according to the fifth embodiment. [Figure 40] FIG. 40 is a second other example of a side view of the light source module according to the fifth embodiment. [Figure 41] FIG. 41 is a side view showing the configuration of a light source module according to Modification 1 of Embodiment 5. FIG. [Figure 42] FIG. 42 is a side view showing the configuration of the light source module according to the sixth embodiment. [Figure 43] FIG. 43 is a side view showing the configuration of a light source module according to Modification 1 of Embodiment 6. As shown in FIG. [Figure 44] FIG. 44 is a side view showing the configuration of the light source module according to the seventh embodiment. [Figure 45] FIG. 45 is a side view showing the configuration of the light source module according to the eighth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, light source modules according to embodiments and modifications of the present disclosure will be described in detail with reference to the drawings. Note that the embodiments and modifications described below each represent a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, component arrangements and connection forms, steps, and step sequences 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" or "rectangular," and numerical ranges are not expressions that only express a strict meaning, but are expressions that mean a substantially equivalent range, for example, including a difference of about a few percent.

[0014] Furthermore, in this specification, the terms "above" and "below" do not refer to the upward direction (vertically upward) and downward direction (vertically downward) in absolute spatial recognition, but are used as terms defined by a relative positional relationship based on the stacking order in a stacked configuration. Furthermore, the terms "above" and "below" are applied not only to a case where two components are arranged with a gap between them and another component exists between them, but also to a case where two components are arranged closely together and the two components are in contact with each other.

[0015] The x-axis, y-axis, and z-axis represent the three axes of a three-dimensional Cartesian coordinate system related to the light source module. The positive direction of the z-axis may be referred to as "upward," and the negative direction of the z-axis may be referred to as "downward." The upper surface may be referred to as "top surface," and the lower surface may be referred to as "bottom surface."

[0016] In each embodiment and each modified example, the direction of travel along the optical axis of the first laser light immediately after being emitted from the semiconductor laser element provided in the light source module is defined as the negative y-axis direction, the direction parallel to the fast axis of the first laser light immediately after being emitted from the semiconductor laser element is defined as the z-axis direction, and the direction parallel to the slow axis of the first laser light immediately after being emitted from the semiconductor laser element is defined as the x-axis direction.

[0017] In the embodiments and modifications described below, a view of the light source module viewed from the positive side of the z-axis is referred to as a top view, a view of the semiconductor laser device viewed from the negative side of the y-axis is referred to as a front view, and a view of the semiconductor laser device viewed from the positive or negative side of the x-axis is referred to as a side view.

[0018] (Embodiment 1) [composition] First, the configuration of the light source module 1010 according to the first embodiment will be described.

[0019] Fig. 1 is a perspective view showing the overall configuration of a light source module 1010 according to embodiment 1. Fig. 2 is a cross-sectional view showing a cut surface of the light source module 1010 taken along line II-II in Fig. 1. Fig. 3 is a cross-sectional view showing a cut surface of the light source module 1010 taken along line III-III in Fig. 1. Note that hatching indicating cross sections has been omitted in Fig. 2.

[0020] 1, 2, and 3, the light source module 1010 includes a semiconductor laser element 200, a submount 230, a pedestal 1240, a fixed base 1250, an optical member 1600, and an output mirror 160. The semiconductor laser element 200 is also a laser diode. The optical member 1600 includes a first cylindrical lens 110, a support member 1120, a laser crystal 1130, a first installation plane, and a terminal mirror 1140. For simplicity, the support member 1120 is omitted from FIG. 3.

[0021] Light source module 1010 is a module that can emit output light L1100, which is laser light based on first laser light L1001 emitted from semiconductor laser element 200. Light source module 1010 is a laser diode pumped solid-state laser.

[0022] The components of the light source module 1010 will be described below.

[0023] First, the base 1240 will be described.

[0024] The base 1240 is a flat mounting base on which the submount 230 is attached. The base 1240 has a flat upper surface (a plane on the positive side of the z-axis) and a lower surface (a plane on the negative side of the z-axis). The upper and lower surfaces are planes parallel to the xy plane. The submount 230 is fixed above the upper surface.

[0025] The base 1240 is made of a material with high thermal conductivity, such as a metal such as Cu or CuW, or a ceramic such as AlN or SiC.

[0026] The submount 230 is a flat-plate-shaped mounting base on which the semiconductor laser element 200 is mounted. The semiconductor laser element 200 is placed above the top surface (the plane on the z-axis positive side) of the flat-plate-shaped submount 230. The top surface of the submount 230 is a plane parallel to the xy plane. It is preferable that a bonding member be provided between the semiconductor laser element 200 and the submount 230.

[0027] The submount 230 is made of a material with high thermal conductivity, such as a crystal such as AlN or SiC, or ceramic.

[0028] Next, the semiconductor laser device 200 will be described.

[0029] 4 is an enlarged perspective view of the semiconductor laser device 200 according to this embodiment. The semiconductor laser device 200 is a device that emits a primary laser beam L1001.

[0030] The semiconductor laser device 200 is a laser device including a semiconductor laminated film formed on a semiconductor substrate and an optical waveguide 200r. A front end facet and a rear end facet are formed at both ends of the optical waveguide 200r, and the front end facet and the rear end facet form a resonator optical system of the semiconductor laser device 200. The semiconductor laminated film includes an active layer 200a, that is, the semiconductor laser device 200 includes the active layer 200a.

[0031] An optical waveguide 200r is formed in the central portion of the semiconductor laser element 200 on the active layer 200a side. The optical waveguide 200r includes a part of the active layer 200a. The first laser light L1001 is emitted from a light-emitting end face 205, which is the front end face of the semiconductor laser element 200. More specifically, the end of the optical waveguide 200r on the light-emitting end face 205 side corresponds to the light-emitting region 201. The first laser light L1001 is emitted from the light-emitting region 201. A p-electrode 200p is formed on the surface of the semiconductor laser element 200 on the active layer 200a side, and an n-electrode 200n is formed on the surface opposite to the surface on the active layer 200a side.

[0032] The semiconductor laser element 200 has a rectangular shape that is long in the waveguiding direction of the optical waveguide 200r. The width (width in the x-axis direction) of the semiconductor laser element 200 is, for example, 100 μm or more and 1 mm or less, and the length (length in the y-axis direction) of the semiconductor laser element 200 is, for example, 500 μm or more and 10 mm or less. The width (width in the x-axis direction) of the optical waveguide 200r is, for example, 1 μm or more and 500 μm or less, and the length (length in the y-axis direction) of the optical waveguide 200r has the same value as the length of the semiconductor laser element 200. The size of the light-emitting region 201 is the same as the size at the light-emitting end face 205 of the optical waveguide 200r, and the thickness of the semiconductor laminated film in the lamination direction (z-axis direction) is, for example, 0.5 μm or more and 3 μm or less.

[0033] The semiconductor laser element 200 emits a first laser light L1001 having a first emission peak wavelength. The semiconductor laser element 200 can change the first emission peak wavelength of the emitted first laser light L1001 depending on the semiconductor material of the semiconductor laser element 200. For example, by using a nitride-based semiconductor laser element containing nitrides of Al, Ga, and In as its main components, the semiconductor laser element 200 can emit a first laser light L1001 having a first emission peak wavelength in the wavelength range of 350 nm to 550 nm, for example. In this embodiment, the first emission peak wavelength is 444 nm.

[0034] Furthermore, for example, by configuring the semiconductor laser element 200 as a semiconductor laser element whose main component is a semiconductor composed of Al, Ga, In, As, and P, the semiconductor laser element 200 can emit the first laser light L1001 having a first emission peak wavelength in the wavelength range of 600 nm to 1600 nm, for example. Note that the semiconductor laser element 200 is not limited to semiconductor laser elements composed of the above-mentioned semiconductor materials, and the wavelength of the first laser light L1001 emitted by the semiconductor laser element 200 is not limited to the above-mentioned wavelength.

[0035] The semiconductor laser element 200 emits a first laser beam L1001 having a predetermined divergence angle. More specifically, the semiconductor laser element 200 converts electric power input from the outside to the optical waveguide 200r into stimulated emission light such as the first laser beam L1001 and emits it from the light emitting region 201, which is one end of the optical waveguide 200r. At this time, the fast axis of the first laser beam L1001 is an axis in the stacking direction of the semiconductor laminated film of the semiconductor laser element 200. In addition, the slow axis, which is orthogonal to the fast axis, is an axis parallel to the stacking plane of the semiconductor laminated film.

[0036] The first laser beam L1001 is emitted from the light-emitting region 201 while spreading. The axis in the direction in which the light intensity of the first laser beam L1001 is greatest is defined as the first optical axis. The spread angle of the emitted first laser beam L1001 is defined as 1 / (e 2 ), the divergence angle θf in the fast axis direction is, for example, between 30° and 70°, and the divergence angle θs in the slow axis direction is, for example, between 3° and 25°. Therefore, the first laser beam L1001 is emitted while diverging at the above divergence angles around the first optical axis. Note that in FIG. 4, when the light intensity of the first laser beam L1001 is 1 / (e 2 ) is depicted by a dashed line, and the spread of the first laser beam L1001 is expressed.

[0037] In Fig. 2, the trajectory of the first light ray LA1 traveling along the first optical axis of the first laser light L1001 emitted from the semiconductor laser element 200 is shown by a broken line. Also, in Fig. 4, the first light ray LA1 and emission direction d1 of the first laser light L1001 are shown. In Fig. 4, the first light ray LA1 and emission direction d1 are both parallel to the y-axis and overlap each other.

[0038] In this embodiment, the optical waveguide 200r of the semiconductor laser element 200 is disposed on the submount 230 side. That is, the semiconductor laser element 200 is fixed by so-called junction-down mounting. The active layer 200a of the semiconductor laser element 200 is disposed so as to be parallel to the upper surface of the submount 230. That is, the active layer 200a is parallel to the surface of the semiconductor laser element 200 on the submount 230 side.

[0039] Therefore, the active layer 200a is a layer parallel to the xy plane, and the fast axis of the first laser light L1001 immediately after being emitted from the semiconductor laser element 200 is the z-axis direction, and the slow axis of the first laser light L1001 is an axis parallel to the x-axis direction.

[0040] Next, the first cylindrical lens 110 of the optical member 1600 will be described.

[0041] In this embodiment, the first laser light L1001 emitted from the semiconductor laser element 200 is directly incident on the first cylindrical lens 110. The first cylindrical lens 110 receives the first laser light L1001 emitted from the semiconductor laser element 200 and changes the divergence angle of the first laser light L1001 in the fast axis direction. In this embodiment, the first cylindrical lens 110 changes the divergence angle of the first laser light L1001 in the fast axis direction to decrease, that is, emits the first laser light L1001 with a small divergence angle in the fast axis direction. Note that the first cylindrical lens 110 may change the divergence angle of the first laser light L1001 in the fast axis direction to increase, that is, emit the first laser light L1001 with a large divergence angle in the fast axis direction.

[0042] The divergence angle in the fast axis direction of the first laser beam L1001 emitted from the first cylindrical lens 110 is, for example, between −1° and +1°. An angle with a negative sign indicates convergence. The first cylindrical lens 110 is a lens that quasi-collimates the first laser beam L1001 in the fast axis direction.

[0043] The first cylindrical lens 110 is an optical component having a power axis having power (refractive power) and a non-power axis. The power axis and the non-power axis are disposed perpendicular to each other. That is, the first cylindrical lens 110 has a first cylindrical surface. The first cylindrical lens 110 has a cylindrical surface that is convexly curved toward the power axis, i.e., the surface of a convex cylinder. The first cylindrical lens 110 is a convex cylindrical lens. The power axis is inclined with respect to the fast axis of the first laser light L1001.

[0044] The first cylindrical lens 110 has an incident surface onto which the first laser beam L1001 is incident and an exit surface from which the laser beam is emitted. In this embodiment, the first cylindrical lens 110 is a plano-convex cylindrical lens with a flat incident surface and a convex exit surface. In this embodiment, the incident surface is a surface parallel to the zx plane. The exit surface is a first cylindrical surface, which is a convex surface whose curved surface is expressed by a spherical function or an aspherical function. The power axis is an axis parallel to the zx plane and inclined with respect to the z axis. Note that in this embodiment, a plano-convex cylindrical lens is used as the first cylindrical lens 110. However, a biconvex cylindrical lens, such as a convex meniscus cylindrical lens with one side convex and the other concave, may also be used.

[0045] The first cylindrical lens 110 is a member made of an inorganic transparent material such as glass, and has an anti-reflection coating film that matches the wavelength of the first laser light L1001 formed on the incident surface and the exit surface of the first laser light L1001.

[0046] Furthermore, the generatrix 115 of the first cylindrical lens 110 will be described.

[0047] The first cylindrical lens 110 is a cylindrical lens having a first cylindrical surface. The first cylindrical surface has a generatrix 115 shown by a dashed line in FIG. 3. The emission surface of the first cylindrical lens 110 is a convex first cylindrical surface. Generally, a generatrix is a straight line at each position when the cylindrical surface (curved surface) of the first cylindrical surface is formed by moving a straight line (when drawn by moving a straight line). Here, the generatrix 115 shown by a dashed line is a straight line that follows the convex vertex of the surface of a convex cylinder, out of the countless generatrixes.

[0048] Next, the support member 1120 of the optical member 1600 will be described.

[0049] FIG. 5 is a perspective view of an optical member 1600 according to this embodiment.

[0050] The support member 1120 is a member that is bonded to the first cylindrical lens 110 and supports the first cylindrical lens 110.

[0051] The support member 1120 is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The support member 1120 has an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The lower surface on the negative side of the z-axis is a plane parallel to the x-y plane. The upper surface on the positive side of the z-axis is a plane inclined from the x-y plane in the x-axis direction. In other words, the upper surface on the positive side of the z-axis is a plane inclined in a direction rotated around the y-axis from the x-y plane. The upper surface of the support member 1120 is bonded to the first cylindrical lens 110. Note that the support member 1120 may be a parallel plate, or the upper surface on the positive side of the z-axis and the lower surface on the negative side of the z-axis of the support member 1120 may be parallel, and the upper surface on the positive side of the z-axis and the lower surface on the negative side of the z-axis of the support member 1120 may be planes inclined in a direction rotated around the y-axis from the x-y plane.

[0052] The support member 1120 is formed by processing a substrate of a semiconductor material such as glass or silicon by partial etching, polishing, cutting, etc. The support member 1120 may also be formed of a metal such as Fe or an Fe alloy, or a ceramic such as Al2O3, ZrO2, Si3N4, or AlN.

[0053] The laser crystal 1130 is an example of an optical element. The first laser light L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131 of the laser crystal 1130. In this embodiment, the laser crystal 1130 has a rectangular parallelepiped shape, and the incident surface 1131 of the laser crystal 1130 is the surface of the laser crystal 1130 facing the semiconductor laser element 200 on the semiconductor laser element 200 side, and is a plane on the y-axis positive side and a plane parallel to the zx plane.

[0054] Laser crystal 1130, which is an example of an optical element, converts first laser light L1001 incident from incident surface 1131 into second laser light L1002 having a second emission peak wavelength different from the first emission peak wavelength. Laser crystal 1130 is a solid-state laser medium, and is excited using the first laser light L1001 as excitation light to emit second laser light L1002. The second emission peak wavelength may be, for example, a wavelength shorter than the first emission peak wavelength, but in this case it is a wavelength longer than the first emission peak wavelength.

[0055] Laser crystal 1130 is a Pr:YLF crystal, but is not limited to this. Laser crystal 1130 may also be another known crystal, such as an Nd:YAG crystal or an Nd:YLF crystal. When laser crystal 1130 is a Pr:YLF crystal, first laser light L1001 having a first emission peak wavelength of 444 nm is converted into second laser light L1002 having a second emission peak wavelength of 640 nm.

[0056] The first installation plane of the optical member 1600 corresponds to the lower surface 130B (the plane on the negative side of the z-axis) of the rectangular parallelepiped shape of the laser crystal 1130. The first installation plane is a plane fixed to the first installation plane of the light source module 1010.

[0057] Terminal mirror 1140 of optical element 1600 is an example of the first optical filter included in light source module 1010. Terminal mirror 1140 is provided on incident surface 1131 of laser crystal 1130. In this embodiment, terminal mirror 1140 is a thin film provided so as to cover the entire surface of incident surface 1131 of laser crystal 1130. In this embodiment, terminal mirror 1140 is a plane mirror that does not have a power axis for the transmitted or reflected light.

[0058] Terminal mirror 1140 reflects second laser light L1002. Terminal mirror 1140 transmits first laser light L1001. As described above, first laser light L1001 and second laser light L1002 have different emission peak wavelengths, that is, terminal mirror 1140 has wavelength selectivity for transmitting and reflecting light.

[0059] Terminating mirror 1140 may be configured to reflect second laser beam L1002 and transmit first laser beam L1001, and may be configured, for example, by a dichroic mirror. In this embodiment, terminating mirror 1140 is configured by a dichroic mirror having a dielectric multilayer film. This allows terminating mirror 1140 to reflect second laser beam L1002 generated in laser crystal 1130 in the negative y-axis direction.

[0060] In this embodiment, the terminating mirror 1140 and the support member 1120 are bonded together. More specifically, the plane on the positive side of the y-axis of the terminating mirror 1140 and the plane on the negative side of the y-axis of the support member 1120 are bonded together. As described above, the upper surface of the support member 1120 is bonded to the first cylindrical lens 110, and therefore the support member 1120 fixes the first cylindrical lens 110 and the laser crystal 1130. In other words, the first cylindrical lens 110 is fixed to the laser crystal 1130.

[0061] The first cylindrical lens 110, support member 1120, laser crystal 1130, and end mirror 1140 are bonded to one another by a direct bonding method such as optical contact. Alternatively, the first cylindrical lens 110, support member 1120, laser crystal 1130, and end mirror 1140 are bonded to one another via a bonding material such as low-melting-point glass. A solder material such as AuSn solder may be used as the bonding material.

[0062] Output mirror 160 is an example of a second optical filter included in light source module 1010. Output mirror 160 has a concave surface and a reflective film 161 provided on the surface of the concave surface facing the positive side of the y-axis. In the present embodiment, the concave surface is spherical. Output mirror 160 (more specifically, reflective film 161) reflects most of the second laser light L1002. Note that, more specifically, reflective film 161, unlike terminal mirror 1140, does not need to reflect all of the second laser light L1002. In other words, output mirror 160 (reflective film 161) reflects a portion of the second laser light L1002 and transmits the other portion of the second laser light L1002. For example, reflective film 161 reflects 90% of the second laser light L1002 incident on reflective film 161 and transmits the remaining 10%, although the reflectance and transmittance are not limited to these.

[0063] Reflection film 161 may be configured to reflect a portion of second laser light L1002 and transmit the other portion of second laser light L1002, and is configured, for example, by a dichroic mirror. In this embodiment, reflection film 161 is configured by a dichroic mirror having a dielectric multilayer film. This allows reflection film 161 to reflect a portion of second laser light L1002 generated by laser crystal 1130 in the positive y-axis direction and transmit the other portion in the negative y-axis direction.

[0064] An anti-reflection film may be provided on the surface opposite to the concave surface of output mirror 160 (the surface opposite to reflective film 161). The anti-reflection film is a film that reduces reflection of part of the light with the wavelength of second laser light L1002 due to a difference in refractive index.

[0065] The second laser light L1002 thus transmitted through the output mirror 160 (reflecting film 161) corresponds to the output light L1100.

[0066] Furthermore, output mirror 160, which is the second optical filter, has a second installation plane. The second installation plane is bottom surface 160B of output mirror 160, and is fixed to a second installation plane. Because output mirror 160 has a spherical concave surface, it has power with respect to incident light in both directions parallel and perpendicular to bottom surface 160B. Note that light source module 1010 according to this embodiment has a second installation plane.

[0067] Fixed base 1250 is an example of a fixing member, and is a flat-plate-shaped mounting base on which pedestal 1240, laser crystal 1130, and output mirror 160 are attached. Fixed base 1250 has flat-plate-shaped upper surface 251T, which is a plane on the positive side of the z-axis. Upper surface 251T is a plane parallel to the xy plane. Pedestal 1240, laser crystal 1130, and output mirror 160 are fixed above upper surface 251T.

[0068] 1, upper surface 251T is provided with placement regions 241, 251, and 261. Placement region 241 has pedestal 1240 placed therein, placement region 251 has laser crystal 1130 placed therein, and placement region 261 has output mirror 160 placed therein.

[0069] In this embodiment, the upper surface 251T of the fixed base 1250 corresponds to the first and second installation planes. That is, the fixed base 1250, which is an example of a fixing member, has the upper surface 251T, which is the first installation plane. More specifically, the upper surface 251T in the placement area 251 is the first installation plane, and the upper surface 251T in the placement area 261 is the second installation plane. The first installation plane and the second installation plane are parallel to each other. The first installation plane (the lower surface 130B of the laser crystal 1130) of the optical member 1600 is fixed to the upper surface 251T, which is the first installation plane. In this embodiment, the second installation plane (the lower surface 160B of the output mirror 160) is fixed to the upper surface 251T, which is the second installation plane that is flush with the first installation plane.

[0070] It is preferable that a bonding member be provided between placement region 241 and pedestal 1240, between placement region 251 and laser crystal 1130, and between placement region 261 and output mirror 160. That is, a bonding member is provided between upper surface 251T, which is the first installation plane, and lower surface 130B, which is the first installation plane, and a bonding member is provided between upper surface 251T, which is the second installation plane, and lower surface 160B of output mirror 160, which is the second installation plane.

[0071] As a result, the upper surface 251T and the lower surface 130B are bonded and fixed, and the upper surface 251T and the lower surface 160B are bonded and fixed. Moreover, the upper surface 251T, which is the first flat installation surface, is also the flat surface to which the optical member 1600 (more specifically, the first cylindrical lens 110) is fixed. In other words, the first cylindrical lens 110 is fixed to the first flat installation surface (upper surface 251T) via the laser crystal 1130, which is an optical element. Furthermore, by fixing the first flat installation surface (lower surface 130B) to the first flat installation surface (upper surface 251T), the optical member 1600 is installed on the fixing base 1250, which is a fixing member.

[0072] Furthermore, upper surface 251T and lower surface 130B are in partial or complete contact with each other, or the gap between upper surface 251T and lower surface 130B is, for example, 5 μm or less. A bonding member, for example, solder, is disposed between upper surface 251T and lower surface 130B, and laser crystal 1130 is firmly fixed to fixed base 1250 by the bonding member.

[0073] In this embodiment, the semiconductor laser device 200 is fixed to the fixing base 1250 so that the active layer 200a is parallel to the first installation plane (upper surface 251T). As described above, the lower surface 160B of the output mirror 160 is the second installation plane, and the second installation plane is fixed to the second installation plane, which is a plane parallel to the first installation plane and the active layer 200a. Here, the first installation plane (upper surface 251T) and the active layer 200a are both parallel to the zy plane, and the lower surface 160B of the output mirror 160, which is the second installation plane, is fixed to the upper surface 251T, which is the first installation plane and the second installation plane.

[0074] The fixed base 1250 is made of a material with high thermal conductivity, such as a metal such as Cu or CuW, or a ceramic such as AlN or SiC.

[0075] Here, attention is focused on a plane parallel to the xy plane or a plane tilted in a direction rotated from the xy plane around the y-axis. In this embodiment, upper surface 251T of fixed base 1250, lower and upper surfaces of pedestal 1240, lower and upper surfaces of submount 230, active layer 200a, lower surface 130B and upper surface of laser crystal 1130, lower surface of support member 1120, and lower surface 160B and upper surface of output mirror 160 are planes parallel to the xy plane. In addition, the upper surface of support member 1120 is a plane tilted in a direction rotated from the xy plane around the y-axis.

[0076] Since the first cylindrical lens 110 is bonded to the upper surface of the support member 1120, the generatrix 115 of the first cylindrical lens 110 is parallel to the upper surface of the support member 1120 and is inclined in a direction rotated around the y-axis from the xy plane. That is, in this embodiment, the generatrix 115 is inclined with respect to the upper surface 251T, which is the first installation plane. The generatrix 115 is also inclined with respect to the lower surface 130B, which is the first installation plane. Furthermore, since the upper surface 251T, the active layer 200a, and the xy plane are parallel, the generatrix 115 is inclined with respect to the active layer 200a of the semiconductor laser device 200.

[0077] Here, the angle formed between the busbar 115 and the active layer 200a is defined as angle θ. The angle θ satisfies |θ|<22.5°. In this embodiment, since the busbar 115 is inclined with respect to the active layer 200a, the angle θ satisfies 0°<|θ|<22.5°.

[0078] The angle between the generatrix 115 and the first installation plane is defined as angle β. Similarly, the angle between the generatrix 115 and the first installation plane is also β. The angle β according to this embodiment satisfies 0°<|β|<45°. Because the active layer 200a and the first installation plane (top surface 251T) are parallel, as shown in FIG. 3, angle β is equal to angle θ.

[0079] Here, we focus on the optical system 290. The light source module 1010 includes the optical system 290, which is composed of a terminal mirror 1140 and an output mirror 160. In other words, the terminal mirror 1140 and the output mirror 160 are each part of the optical system 290. The optical system 290 is a resonator optical system, and the predetermined optical axis of this optical system 290 is the second optical axis LA2. In FIG. 2, the second optical axis LA2, which is the optical axis of the second laser beam L1002, is indicated by a two-dot chain line. The second optical axis LA2 is on an extension of the axis of symmetry of the output mirror 160, and the position of the second optical axis LA2 is determined by the position of the output mirror 160. The resonator mode region M2 exists within the laser crystal 1130 in the resonator optical system, centered on the second optical axis LA2. Strictly speaking, the position of the resonator mode region M2 may deviate slightly from the optimal position depending on the position or inclination of the concave surface of the output mirror 160 and the inclination of the surface of the terminal mirror 1140. As an example, in FIG. 2, the first light ray LA1 and the second optical axis LA2 are parallel to the y-axis and are aligned in a straight line.

[0080] Here, the effects of the light source module 1010 according to this embodiment will be described with reference to Fig. 6 to Fig. 8. Here, the effects obtained by adjusting the position of the optical member 1600 will be described. Fig. 6 to Fig. 8 are all diagrams showing coupling of the first laser light L1001 in the fast axis direction.

[0081] Fig. 6 shows a side view and a cross-sectional view of a light source module 1010 according to this embodiment. More specifically, Fig. 6(a) is a side view of the light source module 1010, and Fig. 6(b) is a cross-sectional view showing a cut surface of the light source module 1010 taken along line VIb-VIb in Fig. 6(a). Note that the support member 1120 is omitted in Fig. 6(b).

[0082] 6, the light emission region 201, the first cylindrical lens 110, and the concave surface of the output mirror 160 are arranged at predetermined positions. In this case, the first light ray LA1 traveling in the emission direction d1 passes through the generatrix 115 and travels without changing direction. The first light ray LA1 that has passed through the first cylindrical lens 110 overlaps with the second optical axis LA2 of the optical system 290 when viewed from the slow axis direction (x-axis direction). In this case, since there is a large overlap between the excitation region M1 of the first laser light L1001, which is the excitation laser light, and the resonator mode region M2, laser oscillation occurs efficiently in the laser crystal 1130. Here, the resonator mode region M2 is a region between the terminating mirror 1140 and the output mirror 160 (more specifically, inside the laser crystal 1130) in an optical resonator configured with the terminating mirror 1140, the output mirror 160, and the laser crystal 1130 disposed between the terminating mirror 1140 and the output mirror 160. The resonator mode region M2 is a region having a predetermined width centered on the second optical axis LA2 determined by the shapes of the terminating mirror 1140 and the output mirror 160. The pumping region M1 is a region in which the first laser beam L1001 has a predetermined optical intensity centered on the first beam LA1 after the first laser beam L1001 enters the laser crystal 1130. In FIG. 6, the external beams of the first laser beam L1001 are shown, and the region between one external beam and the other external beam is the range of the pumping region M1. Furthermore, as the first laser beam L1001 travels through the laser crystal 1130, a portion of the first laser beam L1001 is absorbed by the laser crystal 1130, reducing its light intensity. Therefore, the pumping region M1 is a region within the laser crystal 1130 that extends a predetermined distance from the surface of the laser crystal 1130 where the first laser beam L1001 enters. In FIG. 6, the overlap between the pumping region M1 of the pumping laser beam and the resonator mode region M2 is indicated by hatching. In FIG. 6, the first beam LA1, after passing through the first cylindrical lens 110, overlaps with the second optical axis LA2. Therefore, the overlap between the pumping region M1 and the resonator mode region M2 is large. The first laser beam L1001 that is incident on the resonator mode region M2 within the laser crystal 1130 is stably amplified as the second laser beam L1002.That is, the resonator mode region M2 inside the laser crystal 1130 is a gain region for the second laser light L1002. Therefore, the first laser light L1001 is efficiently converted into the second laser light L1002.

[0083] Fig. 7 shows another first example of a side view and a cross-sectional view of a light source module 1010 according to the present embodiment. More specifically, Fig. 7(a) is another first example of a side view of the light source module 1010, and Fig. 7(b) is another first example of a cross-sectional view showing a cut surface of the light source module 1010 taken along line VIIb-VIIb in Fig. 7(a). Note that the support member 1120 is omitted in Fig. 7(b).

[0084] 7, the second optical axis LA2 of the optical system 290 is positioned at a position shifted toward the positive side of the z-axis relative to the position of the light-emitting region 201. In this case, when the generatrix 115 of the first cylindrical lens 110 is in the emission direction d1, the first laser light L1001 is irradiated at a position on the negative side of the z-axis relative to the second optical axis LA2 of the laser crystal 1130. In this case, when the second optical axis LA2 is positioned on the positive side of the z-axis relative to the emission direction d1, the overlap between the excitation region M1 and the resonator mode region M2 is small, making it difficult for efficient laser oscillation to occur. Furthermore, there are times when laser oscillation does not occur.

[0085] In this case, the position of the first cylindrical lens 110 is moved in the negative direction of the x-axis. Note that in FIG. 7, the entire optical element 1600 is moved in the negative direction of the x-axis. As a result, as shown in FIG. 7(b), the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes, and in this case, the generatrix 115 moves toward the positive side of the z-axis. Specifically, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 is disposed on the positive side of the z-axis with respect to the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels with an inclination toward the positive side of the z-axis. The first ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in Fig. 7(a), the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130. Note that at this time, the positions of the pumping region M1 and the resonator mode region M2 in the laser crystal 1130 differ from their positions in the laser crystal 1130 shown in Fig. 6(a), but because the laser crystal 1130 is a homogeneous medium, laser oscillation occurs with the same efficiency.

[0086] Here, for example, consider a case where the positional relationship between the first cylindrical lens 110 and the light-emitting region 201 changes from (b) in FIG. 6 to (b) in FIG. 7. More specifically, consider a case where the position of the optical element 1600 is moved in the negative direction of the x-axis by a movement amount Δxa, as shown in (b) in FIG. 7. This movement allows the position of the generatrix 115, which overlaps with the position of the light-emitting region 201 in the cross-sectional view shown in (b) in FIG. 7, to be moved in the positive direction of the z-axis by a movement amount Δza. Note that (b) in FIG. 7 shows the movement amounts Δxa and Δza based on the positional relationship between the first cylindrical lens 110 and the light-emitting region 201. In this case, the relationship between the movement amounts Δxa and Δza satisfies the following formula:

[0087] Δza=Δxa×tanθ

[0088] Therefore, as explained above, by satisfying |θ|<22.5°, the movement amount Δza can be made sufficiently small relative to the movement amount Δxa. In other words, the absolute value of the movement amount Δza is always smaller than the absolute value of the movement amount Δxa. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing efficient laser oscillation in the laser crystal 1130.

[0089] Figure 8 shows a second example of a side view and a cross-sectional view of a light source module 1010 according to the present embodiment. More specifically, (a) of Figure 8 shows a second example of a side view of the light source module 1010, and (b) of Figure 8 shows a second example of a cross-sectional view of the light source module 1010 taken along line VIIIb-VIIIb in (a) of Figure 8. Note that the support member 1120 is omitted in (b) of Figure 8.

[0090] 8, the second optical axis LA2 of the optical system 290 is positioned at a position shifted toward the negative side of the z-axis relative to the position of the light-emitting region 201. In this case, when the generatrix 115 of the first cylindrical lens 110 is in the emission direction d1, the first laser light L1001 is irradiated at a position on the positive side of the z-axis relative to the second optical axis LA2 of the laser crystal 1130. In this case, when the second optical axis LA2 is positioned on the negative side of the z-axis relative to the emission direction d1, the overlap between the excitation region M1 and the resonator mode region M2 is small, making it difficult for efficient laser oscillation to occur. Furthermore, there are times when laser oscillation does not occur.

[0091] In this case, the position of the first cylindrical lens 110 is moved in the positive direction of the x-axis. Note that in FIG. 8, the entire optical element 1600 is moved in the positive direction of the x-axis. As a result, as shown in FIG. 8(b), the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes, and in this case, the generatrix 115 moves toward the negative side of the z-axis. Specifically, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 is disposed on the negative side of the z-axis with respect to the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels with an inclination toward the negative side of the z-axis. The first ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in FIG. 8(a), the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130.

[0092] Here, for example, consider a case where the positional relationship between the first cylindrical lens 110 and the light-emitting region 201 changes from (b) in FIG. 6 to (b) in FIG. 8. More specifically, consider a case where the position of the optical element 1600 is moved in the positive direction of the x-axis by a movement amount Δxb, as shown in (b) in FIG. 8. This movement allows the position of the generatrix 115, which overlaps with the position of the light-emitting region 201 in the cross-sectional view shown in (b) in FIG. 8, to be moved in the negative direction of the z-axis by a movement amount Δzb. Note that (b) in FIG. 8 shows the movement amounts Δxb and Δzb based on the positional relationship between the first cylindrical lens 110 and the light-emitting region 201. In this case, the relationship between the movement amounts Δxb and Δzb satisfies the following formula:

[0093] Δzb=Δxb×tanθ

[0094] Therefore, as explained above, by satisfying |θ|<22.5°, the movement amount Δzb can be made sufficiently small relative to the movement amount Δxb. In other words, the absolute value of the movement amount Δzb is always smaller than the absolute value of the movement amount Δxb. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing facility, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing facility. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing efficient laser oscillation in the laser crystal 1130.

[0095] 9 and 10, the effects of light source module 1010 according to this embodiment will be described. Here, the effects obtained by adjusting the position of output mirror 160 will be described. Both Fig. 9 and Fig. 10 are diagrams showing coupling of first laser light L1001 in the slow axis direction.

[0096] FIG. 9 is a top view of a light source module 1010 according to this embodiment.

[0097] 9 shows a light source module 1010 in which the semiconductor laser element 200, optical member 1600, and output mirror 160 are in appropriate positions on the yx plane. At this time, the first light ray LA1 overlaps the second optical axis LA2 of the optical system 290 when viewed from the fast axis direction (z-axis direction), which is a reference state. In this case, the first laser light L1001 is efficiently converted into the second laser light L1002. Furthermore, in this case, since the overlap between the excitation region M1 and the resonator mode region M2 is large, laser oscillation occurs efficiently in the laser crystal 1130.

[0098] FIG. 10 is another example of a top view of a light source module 1010 according to this embodiment.

[0099] When the semiconductor laser element 200 is fixed, its position may shift from the predetermined position. FIG. 10 shows a case where the semiconductor laser element 200 is shifted in the positive x-axis direction compared to FIG. 9 . The dashed line 200M indicates the case where the semiconductor laser element 200 is in the predetermined position. In this case, the first light beam LA1 also moves in the positive x-axis direction. Meanwhile, the output mirror 160 is placed at the predetermined position indicated by the dashed line 160M within the placement region 261 indicated by the dashed line. In this case, the first light beam LA1 passes through a position shifted from the second optical axis (not shown) before adjustment. This reduces the overlap between the excitation region M1 and the resonator mode region M2, resulting in a very small output light beam L1100. In such a case, it is preferable to move the output mirror 160 toward the positive x-axis direction along the top surface 251T (second installation plane) within the placement region 261, as indicated by the black arrow in FIG. 10 . This allows the first light ray LA1 to be superimposed on the second optical axis LA2 when viewed from the fast axis direction (z-axis direction). This increases the overlap between the excitation region M1 and the resonator mode region M2, and the first laser light L1001 is efficiently converted into the second laser light L1002. Note that in a second fixing step described below, the output mirror 160 is fixed to the upper surface 251T.

[0100] As described above, the slow-axis direction of the first laser beam L1001 emitted from the semiconductor laser device 200 can also be adjusted.

[0101] [Light source module manufacturing method] Here, an example of a method for manufacturing the light source module 1010 will be described.

[0102] First, a preparatory step is performed.

[0103] In the preparation step, a terminal mirror 1140 is formed on one surface of the laser crystal 1130. Furthermore, the first cylindrical lens 110 and the support member 1120 are bonded together. Finally, the support member 1120 is bonded onto the surface of the laser crystal 1130 on which the terminal mirror 1140 is formed, so that the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane (lower surface 130B), and they are integrated together. Furthermore, the semiconductor laser element 200, the submount 230, and the pedestal 1240 are bonded together and integrated together.

[0104] Then, the semiconductor laser element 200, the submount 230, and the base 1240 that have been joined together are joined and fixed to a fixed base 1250.

[0105] Next, a first placement step is performed in which the optical member 1600 is placed on the first flat surface so that the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first flat surface (top surface 251T).

[0106] Even after this first placement step is completed, the optical member 1600 and the first flat installation surface (upper surface 251T) are not yet joined together, that is, the relative positions of the optical member 1600 and the fixed base 1250 are not yet fixed. Therefore, at this stage, the optical member 1600 (more specifically, the first cylindrical lens 110) can be moved relative to the position of the semiconductor laser element 200.

[0107] Next, a second arrangement step is performed. In the second arrangement step, output mirror 160, which is a second optical filter, is arranged on a second installation plane. More specifically, bottom surface 160B of output mirror 160, which is the second installation plane, is arranged on top surface 251T, which is the second installation plane.

[0108] Even after this second placement step is completed, output mirror 160 and the second flat installation surface (upper surface 251T) are not joined together, that is, the positions of output mirror 160 and fixed base 1250 are not fixed to each other. Therefore, at this stage, output mirror 160 can be moved relative to the position of semiconductor laser element 200.

[0109] Next, a first alignment step is performed. The first alignment step is a process of moving the optical member 1600 that was placed in the first placement step. The first alignment step is also a process of making the first laser light L1001 emitted from the semiconductor laser element 200 incident on the first cylindrical lens 110 and moving the placed optical member 1600.

[0110] More specifically, the first alignment step is a process of moving the optical element 1600 in two mutually perpendicular directions parallel to the first installation plane (top surface 251T). Here, since the first installation plane (top surface 251T) is parallel to the xy plane, the optical element 1600 can be moved in the x-axis direction and the y-axis direction. The optical element 1600 can be moved along the first installation plane (top surface 251T), and here, the first installation plane (bottom surface 130B) of the optical element 1600 moves along the first installation plane (top surface 251T).

[0111] 7 and 8, when the optical element 1600 is moved in the x-axis direction along the first installation plane, the generatrix 115 of the first cylindrical lens 110 is tilted in the direction rotated around the y-axis from the xy plane, and therefore moves in the z-axis direction at a specific position in the x-axis direction. That is, for example, as shown in Fig. 7, when the position of the optical element 1600 is moved in the negative x-axis direction by a movement amount Δxa, the position of the generatrix 115 that overlaps with the position of the light-emitting region 201 can be moved in the positive z-axis direction by a movement amount Δza.

[0112] Furthermore, when the optical element 1600 is moved, a device such as a collet comes into contact with the support member 1120, etc., thereby moving the optical element 1600. In other words, the collet does not come into direct contact with the first cylindrical lens 110.

[0113] In the first alignment step, the position of the optical member 1600 is moved, that is, the position of the optical member 1600 is adjusted, so that the overlap between the excitation region M1 and the resonator mode region M2 becomes larger.

[0114] Then, the second alignment step is performed, which is a process of moving the output mirror 160 that was placed in the second placement step.

[0115] More specifically, the second alignment step is a process of moving the output mirror 160 in two mutually orthogonal directions parallel to the second installation plane (top surface 251T in the placement area 261). In this embodiment, the second installation plane and the first installation plane are parallel, so the second alignment step can also be considered a process of moving the output mirror 160 in two mutually orthogonal directions parallel to the first installation plane (top surface 251T). Here, because the second installation plane (top surface 251T) is parallel to the xy plane, the output mirror 160 can be moved in the x-axis direction and the y-axis direction, and can also be rotated around the z-axis. The output mirror 160 can be moved along the second installation plane (top surface 251T), and in this case, the second installation plane of the output mirror 160 (the bottom surface 160B of the output mirror 160) moves along the second installation plane (top surface 251T).

[0116] 10, when output mirror 160 is moved in the x-axis direction along the second installation plane, the slow-axis direction of first laser light L1001 can also be adjusted. Note that output mirror 160 can also be adjusted in the same way by being rotated around the z-axis direction along the second installation plane.

[0117] In the first and second alignment steps, the optical member 1600 and the output mirror 160 may be moved while the semiconductor laser element 200 emits the first laser beam L1001. The first laser beam L1001 emitted from the semiconductor laser element 200 is converted into the second laser beam L1002 and output as the output beam L1100.

[0118] At this time, the positions of optical member 1600 and output mirror 160 are adjusted while observing the light intensity of output light L1100 output from output mirror 160. At this time, so-called active alignment is performed in which the positions of optical member 1600 and output mirror 160 are adjusted so that the light intensity of output light L1100 emitted from output mirror 160 is maximized.

[0119] Furthermore, a first fixing step is performed, which is a process of fixing the optical member 1600, which has been moved in the first alignment step, to the first installation plane (top surface 251T).

[0120] For example, when heat is applied to a bonding member provided between the upper surface 251T, which is the first installation plane, and the lower surface 130B, which is the first installation plane, the bonding member (e.g., a solder material) melts, and the optical member 1600 and the first installation plane (upper surface 251T) are fixed. In other words, the first installation plane (lower surface 130B) is fixed to the first installation plane (upper surface 251T), and the optical member 1600 (more specifically, the first cylindrical lens 110) is fixed. At this time, the first installation plane (lower surface 130B) and the first installation plane (upper surface 251T) are parallel planes and arranged with a narrow gap between them. Specifically, the gap is 0 μm (i.e., they are in contact) or a narrow gap of, for example, 5 μm or less. Therefore, when the bonding member hardens after melting, it is possible to prevent the optical member 1600 from being significantly displaced in the direction from the first installation plane (lower surface 130B) toward the first installation plane (upper surface 251T), that is, in the negative direction of the z-axis, due to volume shrinkage. This makes it possible to suppress a decrease in the optical intensity of the output light L1100, which has been adjusted to be maximum by increasing the overlap between the excitation region M1 and the resonator mode region M2 through active alignment.

[0121] Furthermore, a second fixing step is performed, which is a process of fixing the output mirror 160, which has been moved in the second alignment step, to the second installation plane (upper surface 251T).

[0122] For example, when heat is applied to a bonding member provided between the upper surface 251T (second installation plane) and the lower surface 160B (second installation plane) of the output mirror 160, the bonding member (e.g., a solder material) melts, fixing the output mirror 160 to the second installation plane (upper surface 251T). Similarly, the second installation plane (lower surface 160B of the output mirror 160) and the second installation plane (upper surface 251T) are parallel planes with a narrow gap between them. Specifically, the gap is 0 μm (i.e., contact) or a narrow distance of, for example, 5 μm or less. Therefore, when the bonding member hardens after melting, volume contraction can be prevented, preventing the output mirror 160 from significantly shifting in the direction from the lower surface 160B of the output mirror 160 toward the second installation plane (upper surface 251T), i.e., in the negative direction of the z-axis. This makes it possible to prevent a decrease in the optical intensity of the output light L1100, which has been adjusted to be maximum by increasing the overlap between the excitation region M1 and the resonator mode region M2 through active alignment.

[0123] By carrying out the first and second fixing steps, the light source module 1010 shown in FIG. 1 is manufactured.

[0124] Thus, the manufacturing method of the light source module 1010 according to this embodiment is a method including a preparation step, a first placement step, a first alignment step, a first fixing step, a second placement step, a second alignment step, and a second fixing step.

[0125] Although the first alignment step was performed first and the second alignment step was performed later, they may be performed simultaneously, or the second alignment step may be performed first and the first alignment step may be performed later. Also, although the first fixing step was performed first and the second fixing step was performed later, they may be performed simultaneously, or the second fixing step may be performed first and the first fixing step may be performed later. Also, the first alignment step and the second alignment step may be performed alternately multiple times.

[0126] [Effect of angle θ] Here, the influence of the angle θ will be summarized again.

[0127] In this embodiment, the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the active layer 200a, and the angle between the generatrix 115 and the active layer 200a is angle θ. As described above, the angle β, which is the angle between the generatrix 115 and the first installation plane (top surface 251T), and the angle θ are the same in this embodiment. The effect of angle θ on the alignment of the first cylindrical lens 110 will be described below.

[0128] 11 is a diagram showing the relationship between the angle θ according to this embodiment and the amount of movement Δz in the z-axis direction and the amount of movement Δx in the x-axis direction of the first cylindrical lens 110. Note that hereinafter, the amount of movement in the z-axis direction may be referred to as Δz, and the amount of movement in the x-axis direction as Δx. Also, Δxa and Δxb described in FIGS. 7 and 8 are examples of Δx, and Δza and Δzb described in FIGS. 7 and 8 are examples of Δz.

[0129] 11, the horizontal axis represents the angle θ and the vertical axis represents −Δz / Δx. As described above, the angle θ and the angle β are equal, and therefore the angle θ and the angle β are both shown.

[0130] Here, Δz and Δx will be described with reference to FIGS.

[0131] Fig. 12 is a front view showing an example before the optical element 1600 (more specifically, the first cylindrical lens 110) is moved in the x-axis direction in the first alignment step according to this embodiment. Fig. 13 is a front view showing an example after the optical element 1600 (more specifically, the first cylindrical lens 110) is moved in the x-axis direction in the first alignment step according to this embodiment. For simplicity, Figs. 12 and 13 mainly show the first cylindrical lens 110 and the semiconductor laser element 200.

[0132] 12 and 13, a case will be described where the first cylindrical lens 110 moves from the position in FIG. 12 to the position in FIG. 13 in the first alignment step. The amount of movement in the x-axis direction from the position in FIG. 12 to the position in FIG. 13 is assumed to be Δx. When the first cylindrical lens 110 moves by Δx in the x-axis direction from the reference position Z0 of the generatrix 115, the position Z1 of the generatrix 115 that overlaps with the position X0 of the light-emitting region 201 can be moved by Δz in the z-axis direction from the reference position Z0 of the generatrix 115.

[0133] 11 indicates the amount of change in the x-axis direction of the first cylindrical lens 110 in the first alignment step. Δz of the first cylindrical lens 110 in Fig. 11 indicates the amount of change in the z-axis direction deviation between the light emitting region 201 and the generatrix 115 in a front view when the first cylindrical lens 110 moves in the x-axis direction.

[0134] As shown in FIG. 11, when the angle θ satisfies 0°<θ<45°, −Δz / Δx is greater than 0 and less than 1. Similarly, although not shown, when the angle θ satisfies −45°<θ<0°, −Δz / Δx is greater than −1 and less than 0. In summary, when the angle θ satisfies 0°<|θ|<45°, |Δz| / |Δx| is less than 1. That is, in the position adjustment of the optical element 1600 in the first alignment step, the absolute value of Δz is always smaller than the absolute value of Δx. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130. For example, when the angle θ is 6°, the vertical axis in FIG. 11 is 0.1, and the position in the z-axis direction can be adjusted with an accuracy 10 times the equipment accuracy.

[0135] Furthermore, Δz and Δx will be explained.

[0136] Fig. 14 is a diagram showing the relationship between Δx, which is the amount of movement in the x-axis direction, and Δz, which is the amount of movement in the z-axis direction, when the angle θ in this embodiment is a specific angle. Fig. 14 shows Δx and Δz when the angle θ is θ = 0°, 1°, 3°, 6°, and 10°. Here, the angle β has the same value as the angle θ, so it is listed together with θ.

[0137] As described above, when the first cylindrical lens 110 moves in the x-axis direction, the position of the generatrix 115 relative to the light-emitting region 201 moves in the z-axis direction when viewed from the emission direction d1. In other words, movement of the first cylindrical lens 110 in the x-axis direction can be converted into movement of the generatrix 115 in the z-axis direction. For example, when the angle θ is 6°, moving the first cylindrical lens 110 in the x-axis direction by 20 μm (i.e., Δx is 20 μm) can move the position of the generatrix 115 in the z-axis direction by 2 μm (i.e., Δz is 2 μm). In other words, by setting the angle θ to 0<θ<45°, the absolute value of the amount of change in the position of the first cylindrical lens 110 in the z-axis direction can be made gentler than the absolute value of the amount of change in the position of the first cylindrical lens 110 in the x-axis direction. Therefore, the position of the generatrix 115 in the z-axis direction can be adjusted with higher accuracy than the accuracy of the manufacturing equipment. Although not shown, also for -45°<θ<0°, the absolute value of the amount of change in the position of the first cylindrical lens 110 in the z-axis direction can be made gentler with respect to the absolute value of the amount of change in the position of the first cylindrical lens 110 in the x-axis direction. In summary, the above effect can be obtained by setting 0<|θ|<45°.

[0138] Furthermore, it is preferable that the angle θ is set to 0°<|θ|<22.5°. This makes it possible to make |Δz| / |Δx| smaller than 0.4. Therefore, the position of the generatrix 115 in the z-axis direction can be adjusted with higher precision.

[0139] Since β=θ, 0°<|β|<22.5°.

[0140] 14, when the angle θ is θ=0° (i.e., when the generatrix 115 and the active layer 200a are parallel), even if the optical member 1600 is moved in the x-axis direction, the generatrix 115 of the first cylindrical lens 110 does not move in the z-axis direction. Therefore, the above effect cannot be obtained.

[0141] In this embodiment, the first and second installation planes are the same plane, but this is not a limitation. The first and second installation planes may be parallel. For example, the fixed base 1250 may be a stepped base with multiple parallel steps, with the first and second installation planes provided on each step. Alternatively, one or more flat spacers may be disposed on the fixed base 1250, with either the top surface 251T or the top surface of the spacer disposed on the first or second installation plane.

[0142] The following describes modifications 1 to 4 of embodiment 1. The following description focuses on the differences from embodiment 1, and the description of commonalities will be omitted or simplified.

[0143] [First Modification of First Embodiment] Fig. 15 is a perspective view showing the configuration of a light source module 1010a according to Modification 1 of Embodiment 1. Fig. 16 is a cross-sectional view showing the cut surface of light source module 1010a taken along line XVI-XVI in Fig. 15. Note that hatching indicating the cross section is omitted in Fig. 16.

[0144] The light source module 1010a according to this modification has the same configuration as the light source module 1010 according to the first embodiment, except that it includes an optical member 1600a instead of the optical member 1600. The light source module 1010a is a laser diode pumped solid state laser.

[0145] Optical member 1600a has a first cylindrical lens 110, a laser crystal 1130, a first installation plane (lower surface 130B), and a terminal mirror 1140. That is, unlike optical member 1600 according to the first embodiment, optical member 1600a does not have support member 1120.

[0146] The first cylindrical lens 110 is bonded to the terminating mirror 1140 without using a support member 1120. The first cylindrical lens 110 has, for example, an incident surface on which the first laser beam L1001 is incident and an exit surface from which the first laser beam L1001 is emitted, with the incident surface being convex and the exit surface being flat. The flat exit surface of the first cylindrical lens 110 is bonded to the terminating mirror 1140, which is also a flat surface. Therefore, the exit surface of the first cylindrical lens 110 is bonded to the incident surface 1131 of the laser crystal 1130. In this case, the first cylindrical lens 110 and the terminating mirror 1140 may be bonded via a bonding member or by direct bonding such as optical contact. When a bonding member is used, it is preferable to use a material that is transparent to light of the wavelength of the first laser beam L1001, such as low-melting-point glass. This allows first cylindrical lens 110 to be firmly fixed to laser crystal 1130 with a small number of parts.

[0147] The generatrix 115 of the first cylindrical lens 110 according to this modification is inclined with respect to the first installation plane (upper surface 251T) and with respect to the lower surface 130B, which is the first installation plane. That is, the absolute value of the angle β between the generatrix 115 and the first installation plane (upper surface 251T) is greater than 0, and furthermore, 0<|β|<22.5°. The angle θ between the generatrix 115 and the active layer 200a is |θ|<22.5°, more specifically, the angle θ between the generatrix 115 and the active layer 200a is 0°<|θ|<22.5°. Furthermore, the angle β and the angle θ may be equal.

[0148] Then, in the first alignment step, the position of the first cylindrical lens 110 is adjusted by moving the optical member 1600a in the x-axis direction.

[0149] Therefore, as described in the first embodiment, when the optical element 1600a moves in the x-axis direction by a movement amount Δx, the position of the generatrix 115 overlapping the position of the light-emitting region 201 moves in the z-axis direction by a movement amount Δz. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the optical element 1600a in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130. The exit surface of the first cylindrical lens 110 may have, for example, a cylindrical shape with a concave central portion, and the entire exit surface does not need to be in contact with the terminal mirror 1140. Furthermore, the exit surface of the first cylindrical lens 110 may have a central portion with a biconvex cylindrical shape, and a portion of the periphery may have a flange portion that protrudes beyond the central portion, and the flange portion of such a first cylindrical lens 110 may be joined to the terminal mirror 1140.

[0150] [Modification 2 of Embodiment 1] Fig. 17 is a perspective view showing the configuration of a light source module 1010b according to Modification 2 of Embodiment 1. Fig. 18A is a cross-sectional view showing a cut surface of light source module 1010b taken along line XVIIIA-XVIIIA in Fig. 17. Note that hatching indicating a cross section is omitted in Fig. 18A.

[0151] The light source module 1010b according to this modification has the same configuration as the light source module 1010 according to the first embodiment, except that it includes an optical member 1600b instead of the optical member 1600. The light source module 1010b is a laser diode pumped solid-state laser.

[0152] Optical member 1600b has a first cylindrical lens 110, a support member 1120b, a laser crystal 1130, a first installation plane (lower surface 130B), and a terminal mirror 1140. That is, optical member 1600b has a support member 1120b instead of the support member 1120 included in optical member 1600 according to the first embodiment.

[0153] The support member 1120b has a first support member 1121b and a second support member 1122b. The first support member 1121b is a flat plate-shaped member with an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper and lower surfaces of the first support member 1121b are parallel to the xy plane. A portion of the first support member 1121b protrudes from the incident surface 1131 of the laser crystal 1130 toward the semiconductor laser device 200. A portion of the lower surface of the first support member 1121b is bonded to the upper surface of the laser crystal 1130.

[0154] The second support member 1122b is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The second support member 1122b has an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper surface of the second support member 1122b is a plane parallel to the xy plane. The lower surface of the second support member 1122b is a plane inclined in a direction rotated around the y-axis from the xy plane. The upper surface of the second support member 1122b is bonded to another part of the lower surface of the first support member 1121b. The lower surface of the second support member 1122b is bonded to the first cylindrical lens 110.

[0155] The first support member 1121b and the second support member 1122b are formed by the same processing and are made of the same material as the support member 1120 described in embodiment 1. In this modification, the first cylindrical lens 110 can be fixed using the side surface of the laser crystal 1130 other than the incident surface 1131. Therefore, there is no need to provide a bonding surface on the incident surface 1131 of the laser crystal 1130, allowing for greater freedom in designing the optical members.

[0156] In this modification, upper surface 251T of fixed base 1250, active layer 200a, lower surface 130B and upper surface of laser crystal 1130, the lower surface of first support member 1121b, and the upper surface of second support member 1122b are planes parallel to the xy plane. In addition, the lower surface of second support member 1122b is a plane that is tilted from the xy plane in a direction rotated around the y axis.

[0157] Because the first cylindrical lens 110 is bonded to the lower surface of the second support member 1122b, the generatrix 115 of the first cylindrical lens 110 is parallel to the lower surface of the second support member 1122b and is inclined in a direction rotated around the y-axis from the xy plane. In other words, in this modification, the generatrix 115 is inclined with respect to the top surface 251T, which is the first installation surface. The absolute value of the angle β between the generatrix 115 and the first installation surface (top surface 251T) is greater than 0, and is 0<|β|<22.5°. The angle θ between the generatrix 115 and the active layer 200a is |θ|<22.5°. More specifically, the angle θ between the generatrix 115 and the active layer 200a is 0°<|θ|<22.5°. Furthermore, the angle β and the angle θ may be equal. The bus 115 is inclined with respect to the lower surface 130B, which is the first installation plane.

[0158] Then, in the first alignment step, the position of the first cylindrical lens 110 is adjusted by moving the optical member 1600b in the x-axis direction.

[0159] Therefore, as described in the first embodiment, when optical element 1600b moves in the x-axis direction by a movement amount Δx, the position of generatrix 115 overlapping with the position of light-emitting region 201 moves in the z-axis direction by a movement amount Δz, and at this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of optical element 1600b in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. This increases the overlap between excitation region M1 and resonator mode region M2, allowing efficient laser oscillation in laser crystal 1130.

[0160] [Another Example of Modification 2 of Embodiment 1] FIG. 18B is a perspective view showing the configuration of a light source module 1010ba according to another example of the second modification of the first embodiment.

[0161] Light source module 1010ba according to another example of this modification has the same configuration as light source module 1010b according to Modification 2 of Embodiment 1, except for the following three main points: light source module 1010ba is a laser diode pumped solid-state laser. Specifically, the three points are that the first installation plane is upper surface 130T of laser crystal 1130, the first installation plane is lower surface 1125ba of first support member 1121b, and optical member 1600ba according to another example of this modification does not have laser crystal 1130.

[0162] An optical member 1600ba according to another example of this modification includes a first cylindrical lens 110, a support member 1120b, a first installation plane (a lower surface 1125ba of the first support member 1121b), and a terminal mirror 1140. Note that a light source module 1010ba according to this modification includes a laser crystal 1130 and a terminal mirror 1140.

[0163] Furthermore, laser crystal 1130, which is an optical element, has upper surface 130T, which is a first flat surface to be placed.

[0164] As in the second modification of the first embodiment, the busbar 115 is inclined with respect to the upper surface 130T, which is the first installation plane, and is inclined with respect to the lower surface 1125ba, which is the first installation plane. That is, the absolute value of the angle β between the busbar 115 and the first installation plane (upper surface 130T) is greater than 0, and furthermore, 0<|β|<22.5°. Furthermore, the angle θ between the busbar 115 and the active layer 200a is |θ|<22.5°, more specifically, the angle θ between the busbar 115 and the active layer 200a is 0°<|θ|<22.5°. Furthermore, the angle β and the angle θ may be equal.

[0165] First laser light L1001 emitted from semiconductor laser element 200 passes through first cylindrical lens 110 and enters laser crystal 1130 from incident surface 1131, which is the surface on which end mirror 1140 of laser crystal 1130 is formed.

[0166] Then, in the first alignment step, the position of first cylindrical lens 110 is adjusted by moving support member 1120b in the x-axis direction. Note that in another example of this modification, laser crystal 1130 is fixed and not moved in the first alignment step. Also, by fixing lower surface 1125ba, which is the first installation plane, to upper surface 130T, which is the first installation plane, optical member 1600ba according to another example of this modification is installed on laser crystal 1130, which is an optical element.

[0167] Therefore, when the support member 1120b and the first cylindrical lens 110 move by a movement amount Δx in the x-axis direction, the position of the generatrix 115 overlapping with the position of the light-emitting region 201 moves by a movement amount Δz in the z-axis direction. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the support member 1120b in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the precision of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the precision of the manufacturing equipment. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing efficient laser oscillation in the laser crystal 1130. Furthermore, since the first alignment step is performed after the laser crystal 1130 is fixed, heat generated in the laser crystal 1130 can be efficiently dissipated to the fixing base 1250 during the first alignment step.

[0168] [Third Modification of First Embodiment] Fig. 19 is a cross-sectional view showing the configuration of a light source module 1010c according to Modification 3 of Embodiment 1. Fig. 20 is another example of a cross-sectional view showing the configuration of a light source module 1010c according to Modification 3 of Embodiment 1. Note that hatching indicating cross sections is omitted in Figs. 19 and 20.

[0169] The light source module 1010c according to this modification has the same configuration as the light source module 1010a according to the first modification of the first embodiment, except that it includes a second cylindrical lens 105. The light source module 1010c is a laser diode pumped solid-state laser. Note that FIGS. 19 and 20 are views corresponding to the cross-sectional view of FIG. 16.

[0170] The second cylindrical lens 105 is a lens disposed between the first cylindrical lens 110 and the semiconductor laser element 200. That is, the first laser light L1001 emitted from the semiconductor laser element 200 is incident on the second cylindrical lens 105. The first laser light L1001 emitted from the second cylindrical lens 105 is incident on the incident surface of the first cylindrical lens 110. The first laser light L1001 incident on the first laser light L1001 is emitted from the exit surface of the first cylindrical lens 110 that is in contact with the incident surface 1131 of the laser crystal 1130, and is incident on the laser crystal 1130.

[0171] The second cylindrical lens 105 changes the divergence angle of the first laser beam L1001 in the fast axis direction. For example, the second cylindrical lens 105 changes the divergence angle of the first laser beam L1001 in the fast axis direction so that it becomes smaller, that is, the second cylindrical lens 105 emits the first laser beam L1001 with a small divergence angle in the fast axis direction.

[0172] The divergence angle in the fast axis direction of the first laser beam L1001 emitted from the second cylindrical lens 105 is, for example, between -1° and +1°. An angle with a negative sign indicates convergence. The second cylindrical lens 105 is a lens that quasi-collimates the first laser beam L1001 in the fast axis direction.

[0173] The second cylindrical lens 105 is an optical component having a power axis (refractive power) and a non-power axis. The power axis and the non-power axis are disposed perpendicular to each other. That is, the second cylindrical lens 105 has a second cylindrical surface. The second cylindrical lens 105 has a cylindrical surface that is convexly curved toward the power axis, i.e., the surface of a convex cylinder. The second cylindrical lens 105 is a convex cylindrical lens. The power axis is inclined with respect to the fast axis of the first laser light L1001.

[0174] The second cylindrical lens 105 has an incident surface onto which the first laser beam L1001 is incident and an exit surface from which the laser beam is emitted. In this modification, the second cylindrical lens 105 is a plano-convex cylindrical lens with a flat incident surface and a convex exit surface. In this modification, the incident surface is a surface parallel to the zx plane. The exit surface is a second cylindrical surface, which is a convex surface whose curved surface is expressed by a spherical function or an aspherical function. The power axis is an axis parallel to the zx plane and inclined with respect to the z axis. Note that in this modification, a plano-convex cylindrical lens is used as the second cylindrical lens 105, but a biconvex cylindrical lens, such as a convex meniscus cylindrical lens with one side convex and the other concave, may also be used.

[0175] The second cylindrical lens 105 is a member made of an inorganic transparent material such as glass, and has an anti-reflection coating film that matches the wavelength of the first laser light L1001 formed on the incident surface and the exit surface of the first laser light L1001.

[0176] Furthermore, the generatrix of the second cylindrical lens 105 will be described.

[0177] The second cylindrical lens 105 is a cylindrical lens having a second cylindrical surface. The second cylindrical surface has a generatrix. The emission surface of the second cylindrical lens 105 is a convex second cylindrical surface. Generally, a generatrix is a straight line at each position when the cylindrical surface (curved surface) of the second cylindrical surface is formed by moving a straight line (when drawn by moving a straight line). The generatrix of the second cylindrical lens 105 is a straight line that follows the convex vertex of the surface of the convex cylinder, among the countless generatrixes.

[0178] In this modification, the generatrix of the second cylindrical lens 105 is parallel to the xy plane.

[0179] FIG. 19 shows the light source module 1010c after the position of the optical member 1600a has been moved because the second optical axis LA2 was located on the negative side of the z-axis relative to the emission direction d1. In this case, the position of the optical member 1600a is moved in the positive direction of the x-axis. As a result, as shown in FIG. 19, the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes. In this case, the position of the generatrix 115 moves toward the negative side of the z-axis. Specifically, in the fast axis direction of the light-emitting region 201, the generatrix 115 is positioned on the negative side of the z-axis relative to the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 incident on the first cylindrical lens 110 is inclined toward the negative side of the z-axis due to refraction and travels within the first cylindrical lens 110. The first ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in FIG. 19, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and therefore, laser oscillation occurs efficiently in the laser crystal 1130.

[0180] FIG. 20 shows the light source module 1010c after the position of the optical element 1600a has been moved because the second optical axis LA2 was located on the positive side of the z-axis relative to the emission direction d1. In this case, the position of the optical element 1600a is moved in the negative direction of the x-axis. As a result, as shown in FIG. 20, the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes, and in this case, the position of the generatrix 115 moves toward the positive side of the z-axis. Specifically, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 is positioned on the positive side of the z-axis relative to the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 incident on the first cylindrical lens 110 travels with an inclination toward the positive side of the z-axis due to refraction. The first ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in FIG. 20, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and therefore, laser oscillation occurs efficiently in the laser crystal 1130.

[0181] Furthermore, the light source module 1010c according to this modification includes a second cylindrical lens 105. As a result, the divergence angle of the first laser light L1001 in the fast axis direction is controlled by the second cylindrical lens 105, and the first laser light L1001 can be incident on the first cylindrical lens 110. This allows for more freedom in designing the lens optical system that causes the first laser light L1001 emitted from the semiconductor laser element 200 to be incident on the laser crystal 1130, and also allows for more freedom in setting the distance between the semiconductor laser element 200 and the laser crystal 1130.

[0182] [Fourth Modification of First Embodiment] Fig. 21 is a perspective view showing the configuration of a light source module 1010d according to Modification 4 of Embodiment 1. Fig. 22 is a cross-sectional view showing the cut surface of light source module 1010d taken along line XXII-XXII in Fig. 21. Note that hatching indicating the cross section has been omitted in Fig. 22.

[0183] Light source module 1010d according to this modification has the same configuration as light source module 1010 according to the first embodiment, except that it includes nonlinear optical crystal 170. Light source module 1010d is a laser diode pumped solid-state laser, and further includes nonlinear optical crystal 170, which allows light source module 1010 to emit harmonic laser light.

[0184] The nonlinear optical crystal 170 is disposed between the optical element (laser crystal 1130) and the second optical filter (output mirror 160). The second laser light L1002 generated in the laser crystal 1130 enters the nonlinear optical crystal 170 and is converted into the third laser light L1003. The third laser light L1003 is light having a third emission peak wavelength. The third emission peak wavelength is a wavelength different from the first emission peak wavelength and the second emission peak wavelength.

[0185] In this modification, the third emission peak wavelength is half the wavelength of the second emission peak wavelength, that is, the nonlinear optical crystal 170 generates second harmonic waves. More specifically, the third emission peak wavelength is 320 nm, which is half the wavelength of the second emission peak wavelength, 640 nm.

[0186] The nonlinear optical crystal 170 is Li3B3O5 (LBO crystal), but is not limited to this. The nonlinear optical crystal 170 may be another known crystal, CsLiBO. 10 (CLBO crystal) or the like may also be used.

[0187] Nonlinear optical crystal 170 has a rectangular parallelepiped shape. Second laser light L1002 is incident on a plane on the laser crystal 1130 side, which is an incident surface of nonlinear optical crystal 170. At least a portion of second laser light L1002 is converted into third laser light L1003, and third laser light L1003 is emitted from a plane on the output mirror 160 side, which is an emission surface of nonlinear optical crystal 170. Nonlinear optical crystal 170 is placed and fixed in placement region 271 provided on top surface 251T.

[0188] In this modification, output mirror 160 has a reflective film 161d instead of reflective film 161. Furthermore, final mirror 1140 reflects second laser light L1002 and third laser light L1003 and transmits first laser light L1001. Output mirror 160 (reflective film 161d) is configured to reflect second laser light L1002 and transmit third laser light L1003. Note that reflective film 161d may be configured to reflect a portion of the third laser light L1003 and transmit the other portion of the third laser light L1003.

[0189] In this modification, the output light L1100 becomes the third laser light L1003 that has passed through the output mirror 160 (the reflective film 161d).

[0190] Light source module 1010d according to this modification includes nonlinear optical crystal 170. This allows generation of second harmonics based on second laser light L1002. Furthermore, output light L1100 can be third laser light L1003, which is the second harmonic of second laser light L1002 that has passed through output mirror 160 (reflective film 161d).

[0191] [Effects, etc.] The light source module 1010 according to the first embodiment includes a semiconductor laser element 200 that emits a first laser light L1001, and an optical member 1600 that has a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first cylindrical lens 110 receives the first laser light L1001 and changes the divergence angle of the first laser light L1001 in the fast axis direction. The first laser light L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131 of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane. The angle θ between the busbar 115 and the active layer 200a is |θ|<22.5°.

[0192] As a result, as shown in the first embodiment, when the angle θ satisfies 0°<|θ|<22.5°, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx when the position of the optical element 1600 is adjusted. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. In other words, a light source module 1010 whose position can be adjusted with high accuracy is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 becomes large, and laser oscillation can be efficiently generated in the laser crystal 1130.

[0193] The light source module 1010 according to the first embodiment includes a semiconductor laser element 200 that emits a first laser beam L1001, and an optical member 1600 that has a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first cylindrical lens 110 receives the first laser beam L1001 and changes the divergence angle of the first laser beam L1001 in the fast axis direction. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131 of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane. The angle θ between the generatrix 115 and the active layer 200a is |θ|<22.5°.

[0194] As a result, as shown in the first embodiment, when the angle θ satisfies 0°<|θ|<22.5°, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx when the position of the optical element 1600 is adjusted. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. In other words, a light source module 1010 whose position can be adjusted with high accuracy is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 becomes large, and laser oscillation can be efficiently generated in the laser crystal 1130.

[0195] The busbar 115 is inclined with respect to the first installation plane.

[0196] This makes it possible to realize a light source module 1010 in which the busbar 115 is inclined with respect to both the first installation plane and the first installed plane.

[0197] In the light source module 1010 according to the first embodiment, the first cylindrical lens 110 is fixed to the optical element.

[0198] This allows the positions of the first cylindrical lens 110 and the optical element to be adjusted as a unit.

[0199] The light source module 1010 according to the first embodiment includes a fixed member (fixed base 1250) having a first installation plane. The optical member 1600 includes an optical element having the first installation plane. The first cylindrical lens 110 is fixed to the first installation plane via the optical element.

[0200] This allows the first cylindrical lens 110 and the fixed base 1250 to be fixed via the optical element (laser crystal 1130).

[0201] A light source module 1010ba according to another example of the second modification of the first embodiment includes an optical element having a first installation plane. The first installation plane is fixed to the first installation plane, and an optical member 1600ba is installed on the optical element.

[0202] This allows optical member 1600ba according to another example of modified example 2 of embodiment 1 to be fixed to the optical element (laser crystal 1130).

[0203] The light source module 1010 according to the first embodiment includes a fixing member (fixing base 1250) having a first installation plane. The first installation plane is fixed to the first installation plane, and thus the optical member 1600 is installed on the fixing member (fixing base 1250).

[0204] This allows the optical member 1600 to be fixed to the fixed base 1250.

[0205] In the light source module 1010 according to the first embodiment, the first laser light L1001 has a first emission peak wavelength. The optical element converts the first laser light L1001 incident on the optical element into a second laser light L1002 having a second emission peak wavelength different from the first emission peak wavelength.

[0206] As a result, the output light L1100 emitted by the light source module 1010 can include the second laser light L1002 whose emission peak wavelength is controlled.

[0207] In the light source module 1010 according to the first embodiment, the second emission peak wavelength is longer than the first emission peak wavelength.

[0208] As a result, output light L1100 emitted by light source module 1010 can include second laser light L1002, which has a longer emission peak wavelength than the first laser light L1001.

[0209] The light source module 1010 according to the first embodiment includes, on the incident surface 1131, a first optical filter that reflects the second laser light L1002.

[0210] This allows the second laser light L1002 to be reflected in the direction in which the first laser light L1001 is incident on the optical element (negative y-axis direction).

[0211] The light source module 1010 according to the first embodiment includes an optical system 290 having a predetermined optical axis.

[0212] This makes it possible to realize a light source module 1010 equipped with the optical system 290.

[0213] In the light source module 1010 according to the first embodiment, the optical system 290 is a resonator optical system.

[0214] This allows the second laser light L1002 to be confined in the optical system 290, which is a resonator optical system.

[0215] In the light source module 1010 according to the first embodiment, the first optical filter is a part of the optical system 290 .

[0216] This allows the second laser light L1002 to be confined within the optical system 290 by reflection by the first optical filter.

[0217] The light source module 1010 according to the first embodiment includes a second optical filter that reflects the second laser light L1002.

[0218] This allows the second laser light L1002 to be confined within the optical system 290 by reflection by the second optical filter.

[0219] In the light source module 1010 according to the first embodiment, the second optical filter includes a second installation plane, which is fixed to a surface parallel to the first installation plane.

[0220] This allows the second optical filter to be fixed to the top surface 251T, which is a surface parallel to the first installation plane. In the first embodiment, the surface parallel to the first installation plane includes, for example, the second installation plane (top surface 251T). This allows the position of the second optical filter to be adjusted in the x-axis direction or a direction parallel to the xy plane.

[0221] The second installation plane may be fixed to a plane parallel to the active layer 200a. The plane parallel to the active layer 200a includes, for example, the second installation plane (upper surface 251T). This allows the position of the second optical filter to be adjusted in the slow-axis direction of the first laser light L1001.

[0222] In the light source module 1010 according to the first embodiment, the second optical filter has a concave surface and a reflective film 161 provided on the concave surface.

[0223] This makes it possible to control the divergence angle of the second laser light L1002 incident on the second optical filter.

[0224] A light source module 1010d according to the fourth modification of the first embodiment includes a nonlinear optical crystal 170 disposed between the optical element and the second optical filter.

[0225] This makes it possible to generate second harmonics based on the second laser light L1002.

[0226] The light source module 1010c according to the third modification of the first embodiment includes a second cylindrical lens 105 disposed between the first cylindrical lens 110 and the semiconductor laser element 200.

[0227] As a result, the divergence angle of the first laser light L1001 in the fast axis direction is controlled by the second cylindrical lens 105, and the first laser light L1001 can be incident on the first cylindrical lens 110.

[0228] The light source module 1010 according to the first embodiment includes a semiconductor laser element 200 that emits a first laser beam L1001, and an optical member 1600 that has a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first laser beam L1001 is incident on the first cylindrical lens 110, and the first cylindrical lens 110 changes the divergence angle of the first laser beam L1001 in the fast axis direction. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131 of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A manufacturing method for the light source module 1010 according to the first embodiment includes a first arrangement step, a first alignment step, and a first fixing step. In a first placement step, the optical element 1600 is placed on a first installation surface so that the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation surface. In a first alignment step, the first laser light L1001 emitted from the semiconductor laser element 200 is incident on the first cylindrical lens 110, and the placed optical element 1600 is moved in two directions parallel to the first installation surface and perpendicular to each other. In a first fixing step, the first installation surface of the moved optical element 1600 is fixed to the first installation surface. In the first placement step, the angle θ between the generatrix 115 and the active layer 200a is |θ|<22.5°.

[0229] As a result, as shown in the first embodiment, when the angle θ satisfies 0°<|θ|<22.5°, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx when the position of the optical element 1600 is adjusted in the first alignment step. Therefore, when the position of the optical element 1600 in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. In other words, a manufacturing method for the light source module 1010 that allows for accurate position adjustment is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 is increased, allowing efficient laser oscillation in the laser crystal 1130.

[0230] In the light source module 1010 according to the first embodiment, the first cylindrical lens 110 is fixed to the optical element. The first laser light L1001 has a first emission peak wavelength. The optical element converts the first laser light L1001 incident on the optical element into a second laser light L1002 having a second emission peak wavelength different from the first emission peak wavelength. The light source module 1010 includes an optical system 290 having a predetermined optical axis and including a first optical filter and a second optical filter. The first optical filter is provided on an incident surface 1131 and reflects the second laser light L1002. The second optical filter reflects the second laser light L1002. A manufacturing method for the light source module 1010 according to the present embodiment includes a second arrangement step of arranging the second optical filter on a second installation surface, a second alignment step of moving the arranged second optical filter in two directions, and a second fixing step of fixing the moved second optical filter to the second installation surface.

[0231] As a result, as shown in the first embodiment, when the position of the second optical filter is adjusted in the second alignment step, the first light ray LA1 can be made to overlap the second optical axis LA2 when viewed from the fast axis direction (z-axis direction), and therefore the first laser light L1001 is efficiently converted into the second laser light L1002.

[0232] (Embodiment 2) The following describes embodiment 2. The following mainly describes the differences with embodiment 1 and modifications 1 to 4 of embodiment 1, and omits or simplifies the description of commonalities.

[0233] [composition] Fig. 23 is a perspective view showing the configuration of a light source module 1010f according to embodiment 2. Fig. 24 is a cross-sectional view showing a cut surface of the light source module 1010f taken along line XXIV-XXIV in Fig. 23. Fig. 25 is a cross-sectional view showing a cut surface of the light source module 1010f taken along line XXV-XXV in Fig. 23. Note that some of the hatching indicating cross sections is omitted in Fig. 24, and all of the hatching indicating cross sections is omitted in Fig. 25.

[0234] Light source module 1010f according to the present embodiment has the same configuration as light source module 1010 according to the first embodiment, except that it includes optical member 1600f instead of optical member 1600, and that it includes fixing member 1300. Light source module 1010f is a laser diode pumped solid-state laser.

[0235] The optical member 1600f according to the present embodiment includes a first cylindrical lens 110, a support member 1120f, a laser crystal 1130f, a first installation plane, and a terminal mirror 1140.

[0236] The support member 1120f is a member that is bonded to the first cylindrical lens 110 and supports the first cylindrical lens 110. The support member 1120f is a member having a flat plate shape. The support member 1120f has an upper surface on the positive side of the z axis and a lower surface on the negative side of the z axis. The lower surface on the negative side of the z axis and the upper surface on the positive side of the z axis are planes parallel to the xy plane. The upper surface of the support member 1120f is bonded to the first cylindrical lens 110.

[0237] In addition, in this embodiment, the support member 1120f is joined to the surface (incident surface 1131f) of the laser crystal 1130f facing the terminating mirror 1140, and specifically, the plane on the negative side of the y-axis of the support member 1120f and the plane on the positive side of the y-axis of the terminating mirror 1140 are joined.

[0238] Because the first cylindrical lens 110 is bonded to the upper surface of the support member 1120f, the generatrix 115 of the first cylindrical lens 110 is parallel to the upper surface of the support member 1120f and parallel to the xy plane. That is, in this embodiment, the generatrix 115 and the active layer 200a are parallel, and the angle θ between the generatrix 115 and the active layer 200a satisfies |θ|<22.5°. More specifically, θ=0°.

[0239] Laser crystal 1130f differs from laser crystal 1130 only in its shape. Unlike bottom surface 130B of laser crystal 1130, bottom surface 130Bf of laser crystal 1130 is a plane that is inclined in a direction rotated around the y-axis from the xy-plane. It can also be said that laser crystal 1130f has a shape in which a part of the negative side of the z-axis of laser crystal 1130 is cut by a cut surface that is inclined in a direction rotated around the y-axis from the xy-plane. In this embodiment, this bottom surface 130Bf corresponds to the first installation plane. In addition, laser crystal 1130f has an incident surface 1131f onto which the first laser beam L1001 is incident.

[0240] Fixing member 1300 is a member that is bonded to laser crystal 1130f and supports laser crystal 1130f. It can also be said that fixing member 1300 is a member that supports optical member 1600f that has laser crystal 1130f.

[0241] The fixed member 1300 is a member having the shape of a trapezoidal prism, with a surface that is trapezoidal when viewed from the y-axis direction. The fixed member 1300 has an upper surface 301T on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The lower surface of the fixed member 1300 is a plane parallel to the xy plane, and the upper surface 301T of the fixed member 1300 is a plane that is inclined in a direction rotated around the y-axis from the xy plane.

[0242] Fixing member 1300 and laser crystal 1130f are bonded together; more specifically, upper surface 301T of fixing member 1300 and lower surface 130Bf of laser crystal 1130f are parallel to and bonded together. Fixing member 1300 is placed and fixed in placement area 251 provided on upper surface 251T of fixing base 1250. In this embodiment, this upper surface 301T corresponds to the first installation plane. Note that fixing base 1250 to which fixing member 1300 is fixed may also be used as the fixing member.

[0243] As in the first embodiment, output mirror 160 has bottom surface 160B, which is a second installation plane. Output mirror 160 is placed and fixed in placement area 261, which is provided on top surface 251T of fixed base 1250. Note that the second installation plane in this embodiment is top surface 251T in placement area 261. In other words, bottom surface 160B is fixed to the second installation plane. In this embodiment, the first installation plane is top surface 301T, and therefore the first installation plane is also a plane that is tilted in a direction rotated around the y-axis with respect to the second installation plane.

[0244] The fixing member 1300 is made of a material with high thermal conductivity, such as a metal such as Cu or CuW, or a ceramic such as AlN or SiC. The fixing member 1300 may be formed integrally with the fixing base 1250 using the same material.

[0245] Here, we focus on a plane parallel to the xy plane or a plane tilted in a direction rotated around the y-axis from the xy plane. In this embodiment, the active layer 200a is a plane parallel to the xy plane, and the generatrix 115 is parallel to the xy plane. That is, the active layer 200a, the generatrix 115, and the upper surface 251T (second mounting plane) are parallel to one another. That is, the lower surface 160B, which is the second mounting plane, is fixed to the second mounting plane, which is a plane parallel to the generatrix 115 and the active layer 200a. Furthermore, the upper surface 301T of the fixing member 1300, which is the first mounting plane, and the lower surface 130Bf of the laser crystal 1130f, which is the first mounting plane, are parallel to one another and tilted in a direction rotated around the y-axis from the xy plane.

[0246] As described above, the angle θ satisfies θ=0°. The angle β between the generatrix 115 and the first mounting plane (top surface 301T) satisfies 0°<|β|<45°. More specifically, the angle β satisfies 0°<|β|<22.5°. The generatrix 115 is inclined with respect to the top surface 301T, which is the first mounting plane, and is inclined with respect to the bottom surface 130Bf, which is the first mounting plane. Therefore, it can be said that the first mounting plane (top surface 301T) is inclined at an angle greater than 0° and less than 22.5° with respect to the active layer 200a and the second mounting plane (top surface 251T).

[0247] In the above configuration, the first laser beam L1001 emitted from the semiconductor laser element 200 is incident on the first cylindrical lens 110. At this time, the angle θ between the active layer 200a and the generatrix 115 is 0°, that is, the active layer 200a and the generatrix 115 are parallel to each other. Therefore, the fast axis of the first laser beam L1001 is parallel to the power axis of the first cylindrical lens 110, and the slow axis of the first laser beam L1001 is parallel to the non-power axis of the first cylindrical lens 110. Therefore, in this embodiment, the divergence angle of the first laser beam L1001 can be easily controlled by the first cylindrical lens 110. In other words, the first laser beam L1001, whose divergence angle in only the slow axis direction is reduced, is incident on the incident surface 1131f of the laser crystal 1130f, and therefore the excitation region M1 can be easily controlled.

[0248] Next, a manufacturing method of light source module 1010f will be described with reference to Figures 24 to 27. The manufacturing method of light source module 1010f according to this embodiment is a method that includes a preparation step, a first arrangement step, a first alignment step, a first fixing step, a second arrangement step, a second alignment step, and a second fixing step, similar to the light source module according to embodiment 1. Here, the differences from the manufacturing method of the light source module according to embodiment 1 will be mainly described.

[0249] First, the effect of adjusting the position of the optical member 1600f in the first alignment step will be described with reference to FIGS.

[0250] 24 and 25, the upper surface 301T is inclined clockwise at an angle β, where 0°<β<45°, with respect to the upper surface 251T and the xy plane when viewed from the positive direction of the y-axis. The lower surface 130Bf of the optical member 1600f, which serves as the first installation plane, is a plane inclined in a direction rotated by an angle β around the y-axis from the generatrix 115. Therefore, in the first placement step, similar to the first embodiment, the optical member 1600f is placed on the first installation plane (upper surface 301T) so that the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane.

[0251] Since the second optical axis LA2 was located on the negative side of the z-axis relative to the emission direction d1 at the position of the optical member 1600f after the first placement step, FIGS. 24 and 25 show the light source module 1010f after the position of the optical member 1600f has been moved. In this case, the position of the optical member 1600f is moved in the negative direction of the x-axis. As a result, as shown in FIG. 24, the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes. Specifically, in the fast axis direction of the light-emitting region 201, the generatrix 115 is positioned in the negative direction of the z-axis relative to the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels with an inclination toward the negative side of the z-axis. The first ray LA1 is guided to the vicinity of the second optical axis LA2 within the laser crystal 1130f near the incident surface 1131f. As a result, as shown in FIG. 25, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130f.

[0252] As shown in Fig. 24, when the position of optical member 1600f is moved in the negative direction of the x-axis by a movement amount Δxc, the position of generatrix 115, which overlaps with the position of light emitting region 201 in the cross-sectional view shown in Fig. 24, can be moved in the negative direction of the z-axis by a movement amount Δzc. At this time, optical member 1600f is moved so that bottom surface 130Bf (first installation plane) of laser crystal 1130f of optical member 1600f is aligned with top surface 301T (first installation plane) of fixing member 1300. At this time, the relationship between movement amount Δxc and movement amount Δzc satisfies the following formula.

[0253] Δzc=Δxc×tanβ

[0254] Therefore, even when θ=0°, by ensuring that 0°<|β|<45°, or even better, 0°<|β|<22.5°, the absolute value of the movement amount Δzc can be made sufficiently small relative to the absolute value of the movement amount Δxc, as described in the first embodiment. In other words, the absolute value of the movement amount Δzc is always smaller than the absolute value of the movement amount Δxc. Therefore, when the position of the optical element 1600f in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130f.

[0255] Then, a second alignment step is performed, which is a process of moving the output mirror 160 in two mutually perpendicular directions parallel to the second installation plane (the upper surface 251T in the placement region 261). In this embodiment, the first installation plane is inclined with respect to the second installation plane. However, in the first alignment step, the optical member 1600f moves along the first installation plane (the upper surface 301T), thereby substantially moving the generatrix 115 in the z-axis direction. Meanwhile, since the second installation plane is parallel to the xy plane, the output mirror 160 can be moved in the x-axis and y-axis directions. This allows for a larger overlap between the excitation region M1 and the resonator mode region M2 in both the x-axis and z-axis directions. Note that in this embodiment, the second installation plane is parallel to the active layer 200a. Therefore, the output mirror 160 can be adjusted to the slow-axis direction of the first laser light L1001. Therefore, it can be said that the overlap between the excitation region M1 and the resonator mode region M2 can be increased in both the slow axis direction and the fast axis direction of the first laser light L1001.

[0256] Furthermore, the effect of adjusting the position of the optical member 1600f in the first alignment step will be described with reference to FIGS.

[0257] Fig. 26 is another example of a cross-sectional view showing a cut surface of light source module 1010f taken along line XXIV-XXIV in Fig. 23. Fig. 26 is a cross-sectional view before the first alignment step is performed. Fig. 27 is a cross-sectional view after the first alignment step is performed on light source module 1010f shown in Fig. 26. Some of the hatching indicating the cross section is omitted in Figs. 26 and 27.

[0258] Unlike FIGS. 24 and 25, FIG. 27 shows the light source module 1010f after the position of the optical member 1600f has been moved because the second optical axis LA2 was located further toward the positive side of the z-axis than the emission direction d1. In this case, the position of the optical member 1600f is moved in the positive direction of the x-axis. As a result, the generatrix 115 is moved in the positive direction of the z-axis, and the positional relationship between the generatrix 115 of the first cylindrical lens 110 and the light-emitting region 201 changes. Specifically, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 is positioned further toward the positive side of the z-axis than the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels with an inclination toward the positive side of the z-axis. The first ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130f near the incident surface 1131f. As a result, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130f.

[0259] As shown in Fig. 27, when the position of optical member 1600f is moved in the positive direction of the x-axis by a movement amount Δxd, the position of generatrix 115, which overlaps with the position of light emitting region 201 in the cross-sectional view shown in Fig. 27, can be moved in the positive direction of the z-axis by a movement amount Δzd. At this time, optical member 1600f is moved so that bottom surface 130Bf (first installation plane) of laser crystal 1130f of optical member 1600f is aligned with top surface 301T (first installation plane) of fixing member 1300. At this time, the relationship between movement amount Δxd and movement amount Δzd satisfies the following formula.

[0260] Δzd=Δxd×tanβ

[0261] Therefore, even when θ=0°, by satisfying 0°<|β|<22.5°, the absolute value of the movement amount Δzd can be made sufficiently small relative to the absolute value of the movement amount Δxd, as described in the first embodiment. In other words, the absolute value of the movement amount Δzd is always smaller than the absolute value of the movement amount Δxd. Therefore, when the position of optical element 1600f in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy.

[0262] With the above configuration, even if the second optical axis LA2 is located on the negative side of the z-axis or the positive side of the z-axis with respect to the emission direction d1, the traveling direction of the first light ray LA1 can be adjusted in the first alignment step. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing efficient laser oscillation in the laser crystal 1130f.

[0263] Furthermore, the lower surface 130Bf (first installation plane) is adjusted along the upper surface 301T (first installation plane) of the fixing member 1300. Therefore, in the first fixing step, the lower surface 130Bf and the upper surface 301T can be firmly fixed together using a joining member or the like.

[0264] The following describes Modifications 1 and 2 of Embodiment 2. The following mainly describes the differences from Embodiment 2 and the like, and omits or simplifies the description of commonalities.

[0265] [Modification 1 of Embodiment 2] FIG. 28 is a perspective view showing a configuration of a part of a light source module according to Modification 1 of Embodiment 2. As shown in FIG.

[0266] The light source module according to this modification has the same configuration as the light source module 1010f according to the second embodiment, except that it includes an optical member 1600g instead of the optical member 1600f.

[0267] The optical member 1600g includes a first cylindrical lens 110, a support member 1120g, a laser crystal 1130, a first installation plane, and a terminal mirror 1140.

[0268] This modification has a first cylindrical lens 110 similar to that of the first modification of the first embodiment. Similarly to the first modification of the first embodiment, the first cylindrical lens 110 of this modification is bonded to the end mirror 1140 without a support member 1120g or the like. The generatrix 115 and the active layer 200a are parallel to each other, and the angle θ between the generatrix 115 and the active layer 200a satisfies |θ|<22.5°. More specifically, θ=0°. In FIG. 28 , as an example, the first cylindrical lens 110 has a convex entrance surface for the first laser beam L1001 and a flat exit surface, and the exit surface for the first laser beam L1001 is bonded to the entrance surface 1131 of the laser crystal 1130. The first laser beam L1001 passes through the first cylindrical lens 110 and is incident on the entrance surface 1131 of the laser crystal 1130.

[0269] Support member 1120g is a member that is bonded to laser crystal 1130 and supports laser crystal 1130.

[0270] The support member 1120g is a member having the shape of a trapezoidal prism, with a surface that is trapezoidal when viewed from the y-axis direction. The support member 1120g has an upper surface on the positive side of the z-axis and a lower surface 1125g on the negative side of the z-axis. The upper surface of the support member 1120g is a plane parallel to the xy plane, and the lower surface 1125g of the support member 1120g is a plane that is tilted in a direction rotated around the y-axis from the xy plane.

[0271] Support member 1120g and laser crystal 1130 are bonded together; more specifically, an upper surface of support member 1120g and a lower surface 130B of laser crystal 1130 are parallel and bonded together. Support member 1120g and fixing member 1300 are also bonded together; more specifically, a lower surface 1125g of support member 1120g and an upper surface 301T of fixing member 1300 are parallel and bonded together. In this modification, lower surface 1125g corresponds to the first installation plane, and upper surface 301T of fixing member 1300 corresponds to the first installation plane.

[0272] Support member 1120g is preferably made of a material with high thermal conductivity similar to that of fixing member 1300. In this modification, laser crystal 1130 is fixed using support member 1120g having lower surface 1125g that is inclined with respect to the xy plane, thereby forming optical member 1600g. Therefore, there is no need to perform special processing on laser crystal 1130, such as forming an inclined surface, and the light source module can be easily constructed.

[0273] In this modified example, the angle θ between the busbar 115 and the active layer 200a satisfies θ=0°, and the angle β between the busbar 115 and the first installation plane (top surface 301T) satisfies 0°<|β|<45°, and more specifically, 0°<|β|<22.5°.

[0274] Then, in the first alignment step, the optical member 1600g is moved in the x-axis direction to adjust the position of the first cylindrical lens 110. Note that the first alignment step is performed after the fixing member 1300 is fixed to the upper surface 251T.

[0275] Therefore, as described in the second embodiment, when optical element 1600g moves in the x-axis direction by a movement amount Δx, the position of generatrix 115 overlapping with the position of light-emitting region 201 moves in the z-axis direction by a movement amount Δz, and at this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of optical element 1600g in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. This increases the overlap between excitation region M1 and resonator mode region M2, allowing efficient laser oscillation in laser crystal 1130.

[0276] [Modification 2 of Embodiment 2] FIG. 29A is a perspective view showing a configuration of a part of a light source module according to Modification 2 of Embodiment 2. FIG.

[0277] The light source module of this modified example has the same configuration as the light source module 1010f of embodiment 2, except that it has optical member 1600h instead of optical member 1600f, and has first auxiliary member 1121h and second auxiliary member 1122h.

[0278] The optical member 1600h includes a first cylindrical lens 110, a support member 1120h, a laser crystal 1130, a first installation plane, and a terminal mirror 1140.

[0279] The first auxiliary member 1121h is a member having a flat plate shape, and has an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper and lower surfaces of the first auxiliary member 1121h are parallel to the xy plane. A part of the first auxiliary member 1121h protrudes from the incident surface 1131 of the laser crystal 1130 toward the semiconductor laser device 200. A part of the lower surface of the first auxiliary member 1121h is bonded to the upper surface of the laser crystal 1130.

[0280] The second auxiliary member 1122h is a member having a flat plate shape. The second auxiliary member 1122h has an upper surface on the positive side of the z axis and a lower surface on the negative side of the z axis. The upper and lower surfaces of the second auxiliary member 1122h are parallel to the xy plane. The upper surface of the second auxiliary member 1122h is bonded to the other part of the lower surface of the first auxiliary member 1121h. The lower surface of the second auxiliary member 1122h is bonded to the first cylindrical lens 110.

[0281] Support member 1120h is a member having the same shape as support member 1120g described in Modification 1 of Embodiment 2. An upper surface of support member 1120h and lower surface 130B of laser crystal 1130 are parallel to and bonded together. Support member 1120h and fixing member 1300 are also bonded together; more specifically, lower surface 1125h of support member 1120h and upper surface 301T of fixing member 1300 are parallel to and bonded together. In this modification, lower surface 1125h corresponds to the first installation plane, and upper surface 301T of fixing member 1300 corresponds to the first installation plane.

[0282] The first auxiliary member 1121h, the second auxiliary member 1122h, and the support member 1120h are formed by the same processing as the support member 1120 described in the first embodiment, and are also formed from the same material.

[0283] In this modification, as in the second modification of the first embodiment, the first cylindrical lens 110 is bonded to the laser crystal 1130 via a support member 1120h. In this modification as well, the first cylindrical lens 110 can be fixed using a side surface of the laser crystal 1130 other than the incident surface 1131. Therefore, there is no need to provide a bonding surface on the incident surface 1131 of the laser crystal 1130, allowing for greater freedom in designing the optical component.

[0284] Because the first cylindrical lens 110 is bonded to the lower surface of the second auxiliary member 1122h, the generatrix 115 is parallel to the lower surface of the second auxiliary member 1122h and parallel to the xy plane. Therefore, the generatrix 115 and the active layer 200a are parallel, and the angle θ between the generatrix 115 and the active layer 200a satisfies |θ|<22.5°. More specifically, θ=0°.

[0285] Moreover, the angle β formed between the bus 115 and the first installation plane (upper surface 301T) satisfies 0°<|β|<45°, and more specifically, 0°<|β|<22.5°.

[0286] Then, in the first alignment step, the optical member 1600h is moved in the x-axis direction to adjust the position of the first cylindrical lens 110. Note that the first alignment step is performed after the fixing member 1300 is fixed to the upper surface 251T.

[0287] Therefore, as described in the second embodiment, when the optical element 1600h moves in the x-axis direction by the movement amount Δx, the position of the generatrix 115 that overlaps with the position of the light-emitting region 201 moves in the z-axis direction by the movement amount Δz, and at this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the optical element 1600h in the x-axis direction is adjusted by the manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130.

[0288] [Third Modification of Second Embodiment] FIG. 29B is a perspective view showing a configuration of a part of a light source module according to Modification 3 of Embodiment 2. FIG.

[0289] The light source module according to this modification has the same configuration as the light source module according to the first modification of the second embodiment, except that it includes an optical member 1600ha instead of the optical member 1600g.

[0290] The optical member 1600ha includes a first cylindrical lens 110, a support member 1120ha, a first installation plane, a laser crystal 1130, and a terminal mirror 1140.

[0291] The support member 1120ha has a first support member 1121ha and a second support member 1122ha. The first support member 1121ha is a flat plate-shaped member with an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper and lower surfaces of the first support member 1121ha are parallel to the xy plane. The lower surface of the first support member 1121ha is bonded to the upper surface of the second support member 1122ha. The upper surface of the first support member 1121ha is bonded to the first cylindrical lens 110.

[0292] Second support member 1122ha is a member having the same shape as support member 1120g described in Modification 1 of Embodiment 2. An upper surface of second support member 1122ha and lower surface 130B of laser crystal 1130 are parallel to and bonded together. Second support member 1122ha and fixing member 1300 are also bonded together; more specifically, lower surface 1125ha of second support member 1122ha and upper surface 301T of fixing member 1300 are parallel to and bonded together. In this modification, lower surface 1125ha corresponds to the first installation plane, and upper surface 301T of fixing member 1300 corresponds to the first installation plane.

[0293] In this modification, as in the second modification of the second embodiment, the angle θ between the busbar 115 and the active layer 200a satisfies |θ|<22.5°, more specifically, θ=0°.

[0294] Moreover, the angle β formed between the bus 115 and the first installation plane (upper surface 301T) satisfies 0°<|β|<45°, and more specifically, 0°<|β|<22.5°.

[0295] Then, in the first alignment step, the optical member 1600ha is moved in the x-axis direction to adjust the position of the first cylindrical lens 110. Note that the first alignment step is performed after the fixing member 1300 is fixed to the upper surface 251T.

[0296] Therefore, as described in the second embodiment, when the optical element 1600ha moves in the x-axis direction by a movement amount Δx, the position of the generatrix 115 overlapping the position of the light-emitting region 201 moves in the z-axis direction by a movement amount Δz. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the optical element 1600ha in the x-axis direction is adjusted using manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the precision of the manufacturing equipment, and the position in the z-axis direction can be adjusted with an accuracy higher than the precision of the manufacturing equipment. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130. In this modification, the first cylindrical lens 110 can be fixed to the laser crystal 1130 using the first support member 1121ha and the second support member 1122ha. Therefore, there is no need to provide a bonding surface on the incident surface 1131 of the laser crystal 1130, allowing for greater freedom in the design of the optical element.

[0297] [Fourth Modification of the Second Embodiment] Fig. 29C is a perspective view showing the configuration of light source module 1010bb according to Variation 4 of Embodiment 2. Fig. 29D is a cross-sectional view showing a cut surface of laser crystal 1130 and first support member 1121bb taken along line XXIXD-XXIXD in Fig. 29C. Note that in Fig. 29D, first cylindrical lens 110 and second support member 1122bb do not appear on the cut surface, but are shown by dashed lines to indicate their positions. Note that hatching indicating a cross section has been omitted in Fig. 29D.

[0298] Light source module 1010bb according to this modification has the same configuration as light source module 1010b according to modification 2 of embodiment 1, except for the following three main points: light source module 1010bb is a laser diode pumped solid-state laser. Specifically, the three points are that laser crystal 1130bb is provided instead of laser crystal 1130, the first installation plane and the first installation plane are changed, and optical member 1600hb according to this modification does not have laser crystal 1130bb.

[0299] The laser crystal 1130bb differs from the laser crystal 1130 only in its shape. While the top surface of the laser crystal 1130 was a plane parallel to the xy plane, the top surface 130Tb of the laser crystal 1130bb is a plane tilted in a direction rotated around the y-axis from the xy plane. It can also be said that the laser crystal 1130bb has a shape obtained by cutting a part of the positive side of the z-axis of the laser crystal 1130bb along a cut surface tilted in a direction rotated around the y-axis from the xy plane. This top surface 130Tb corresponds to the first installation plane. The laser crystal 1130bb also has an incident surface 1131bb onto which the first laser beam L1001 is incident.

[0300] The optical member 1600hb according to this modification includes a first cylindrical lens 110, a support member 1120bb, a first installation plane, and a terminal mirror 1140.

[0301] The support member 1120bb has a first support member 1121bb and a second support member 1122bb. The first support member 1121bb is a member having the shape of a trapezoidal prism, with a trapezoidal surface when viewed from the y-axis direction, and has an upper surface on the positive side of the z-axis and a lower surface 1125bb on the negative side of the z-axis. The upper surface of the first support member 1121bb is parallel to the xy plane. The lower surface 1125bb of the first support member 1121bb is a plane that is inclined in a direction rotated around the y-axis from the xy plane. A portion of the lower surface 1125bb of the first support member 1121bb is bonded to the upper surface 130Tb of the laser crystal 1130bb.

[0302] The second support member 1122bb is a member having the shape of a trapezoidal prism, with a trapezoidal surface when viewed from the y-axis direction, and has an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper surface of the second support member 1122bb is a plane that is inclined in a direction rotated around the y-axis from the xy plane. The lower surface of the second support member 1122bb is a plane parallel to the xy plane. The upper surface of the second support member 1122bb is bonded to the other part of the lower surface 1125bb of the first support member 1121bb. The lower surface of the second support member 1122bb is bonded to the first cylindrical lens 110.

[0303] Since the first cylindrical lens 110 is bonded to the lower surface of the second support member 1122bb, the generatrix 115 of the first cylindrical lens 110 is parallel to the lower surface of the second support member 1122bb and parallel to the xy plane.

[0304] In this modification, the first installation plane is the lower surface 1125bb of the first support member 1121bb.

[0305] In this modification, as in the second modification of the second embodiment, the angle θ between the busbar 115 and the active layer 200a satisfies |θ|<22.5°, more specifically, θ=0°.

[0306] Moreover, the angle β formed between the bus 115 and the first installation plane (upper surface 130Tb) satisfies 0°<|β|<45°, and more specifically, 0°<|β|<22.5°.

[0307] Then, in the first alignment step, the position of the first cylindrical lens 110 is adjusted by moving the optical member 1600hb according to this modified example in the x-axis direction.

[0308] Therefore, as described in the second embodiment, when the optical element 1600hb according to this modification moves in the x-axis direction by a movement amount Δx, the position of the generatrix 115 overlapping the position of the light-emitting region 201 moves in the z-axis direction by a movement amount Δz. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the optical element 1600hb according to this modification in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130bb. In this modification, the fast axis of the first laser beam L1001 and the power axis of the first cylindrical lens 110 can be aligned parallel to each other, and the first cylindrical lens 110 can be fixed using the side of the laser crystal 1130bb that is not the incident surface 1131bb. Therefore, with a simple configuration, first laser beam L1001 with an adjusted divergence angle can be made incident on incident surface 1131bb of laser crystal 1130bb.

[0309] [Effects, etc.] A light source module 1010f according to the second embodiment includes a semiconductor laser element 200 that emits a first laser beam L1001, and an optical member 1600f that has a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first cylindrical lens 110 receives the first laser beam L1001 and changes the divergence angle of the first laser beam L1001 in the fast axis direction. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131f of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane. The angle θ between the busbar 115 and the active layer 200a is |θ|<22.5°.

[0310] As a result, as shown in the second embodiment, when θ=0° and the angle β between the generatrix 115 and the first installation plane (upper surface 301T) satisfies 0°<|β|<22.5°, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx when the position of the optical member 1600f is adjusted. Therefore, when the position of the optical member 1600f in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. In other words, a light source module 1010f whose position can be adjusted with high accuracy is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 becomes large, and laser oscillation can be efficiently generated in the laser crystal 1130f.

[0311] A light source module 1010f according to the second embodiment includes a semiconductor laser element 200 that emits a first laser beam L1001, and an optical member 1600f that has a first cylindrical lens 110 and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first cylindrical lens 110 receives the first laser beam L1001 and changes the divergence angle of the first laser beam L1001 in the fast axis direction. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131f of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane. The angle θ between the busbar 115 and the active layer 200a is |θ|<22.5°.

[0312] As a result, as shown in the second embodiment, when θ=0° and the angle β between the generatrix 115 and the first installation plane (upper surface 301T) satisfies 0°<|β|<22.5°, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx when the position of the optical member 1600f is adjusted. Therefore, when the position of the optical member 1600f in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. In other words, a light source module 1010f whose position can be adjusted with high accuracy is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 is large, and laser oscillation can be efficiently generated in the laser crystal 1130f.

[0313] The light source module 1010f according to the second embodiment includes a semiconductor laser element 200 that emits a first laser beam L1001, and an optical member 1600f that has a first cylindrical lens 110, an optical element, and a first installation plane. The semiconductor laser element 200 has an active layer 200a. The first laser beam L1001 is incident on the first cylindrical lens 110, and the first cylindrical lens 110 changes the divergence angle of the first laser beam L1001 in the fast axis direction. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on an incident surface 1131f of the optical element. The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens 110. A manufacturing method for the light source module 1010f according to the second embodiment includes a first arrangement step, a first alignment step, and a first fixing step. In the first placement step, the optical member 1600f is placed on the first installation plane so that the generatrix 115 of the first cylindrical lens 110 is inclined with respect to the first installation plane. In the first alignment step, the first laser light L1001 emitted from the semiconductor laser element 200 is incident on the first cylindrical lens 110, and the placed optical member 1600f is moved in two directions parallel to the first installation plane and perpendicular to each other. In the first fixing step, the first installation plane of the moved optical member 1600f is fixed to the first installation plane. In the first placement step, the angle θ between the generatrix 115 and the active layer 200a is |θ|<22.5°.

[0314] As a result, as shown in the second embodiment, when θ=0° and the angle β, which is the angle between the generatrix 115 and the first installation plane (upper surface 301T), satisfies 0°<|β|<22.5°, when the position of the optical member 1600f is adjusted in the first alignment step, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of the optical member 1600f in the x-axis direction is adjusted by manufacturing equipment, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. In other words, a manufacturing method for the light source module 1010f that allows for accurate position adjustment is realized. As a result, the overlap between the excitation region M1 and the resonator mode region M2 is increased, allowing efficient laser oscillation in the laser crystal 1130f.

[0315] (Embodiment 3) The following describes embodiment 3. The following description focuses on the differences from embodiment 2, and the description of commonalities will be omitted or simplified.

[0316] [composition] Fig. 30 is a perspective view showing the configuration of a light source module 1010j according to embodiment 3. Fig. 31 is a cross-sectional view showing the cut surface of the light source module 1010j taken along line XXXI-XXXI in Fig. 30. Note that hatching indicating the cross section is omitted in Fig. 31.

[0317] Light source module 1010j according to the present embodiment has the same configuration as light source module 1010f according to the second embodiment, mainly except for the fact that light source module 1010j includes optical member 1600j instead of optical member 1600f and that fixing member 1300j instead of fixing member 1300. Light source module 1010j is a laser diode pumped solid-state laser.

[0318] Optical member 1600j according to this embodiment includes first cylindrical lens 110, support member 1120j, and first installation plane. In this embodiment, light source module 1010j includes laser crystal 1130 and terminal mirror 1140.

[0319] First, the fixing member 1300j will be described.

[0320] The fixing member 1300j is a member that is joined to the support member 1120j and supports the support member 1120j.

[0321] The fixing member 1300j is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The fixing member 1300j has an upper surface 301Tj on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The lower surface of the fixing member 1300j is a plane parallel to the xy plane, and the upper surface 301Tj of the fixing member 1300j is a plane inclined in a direction rotated around the y-axis from the xy plane. In this embodiment, this upper surface 301Tj corresponds to the first installation plane. The fixing member 1300j is placed in a placement area 131 provided on the upper surface 251T.

[0322] The fixing member 1300j is formed by processing a substrate of a semiconductor material such as glass or silicon by partial etching, polishing, cutting, etc. The fixing member 1300j may also be formed of a metal such as Fe or an Fe alloy, or a ceramic such as Al2O3, ZrO2, Si3N4, or AlN.

[0323] Next, the support member 1120j of the optical member 1600j will be described.

[0324] The support member 1120j is a member that is bonded to the first cylindrical lens 110 and supports the first cylindrical lens 110.

[0325] The support member 1120j is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The support member 1120j has an upper surface on the positive side of the z-axis and a lower surface 1125j on the negative side of the z-axis. The upper surface of the support member 1120j is a plane parallel to the xy plane, and the lower surface 1125j of the support member 1120j is a plane tilted in a direction rotated around the y-axis from the xy plane.

[0326] The support member 1120j and the first cylindrical lens 110 are bonded together; more specifically, the upper surface of the support member 1120j and the lower surface of the first cylindrical lens 110 are parallel and bonded together. The support member 1120j and the fixing member 1300j are also bonded together; more specifically, the lower surface 1125j of the support member 1120j and the upper surface 301Tj of the fixing member 1300j are parallel and bonded together. In this embodiment, the lower surface 1125j corresponds to the first installation plane, and the upper surface 301Tj of the fixing member 1300j corresponds to the first installation plane.

[0327] The support member 1120j is fabricated by the same processing as the support member 1120 described in the first embodiment, and is made of the same material.

[0328] 31, the support member 1120j is provided so as to protrude further toward the light emitting region 201 of the semiconductor laser device 200, i.e., toward the positive side of the y-axis, than the fixing member 1300j. The support member 1120j protrudes toward the positive side of the y-axis by a distance d110 than the fixing member 1300j. In other words, a portion of the upper surface 301Tj of the fixing member 1300j and a portion of the lower surface 1125j of the support member 1120j are joined together.

[0329] This allows the first cylindrical lens 110 to be brought closer to the semiconductor laser element 200 even when the fixing member 1300j and the pedestal 1240 are spaced apart to prevent contact between them when they are fixed to the fixed base 1250. As a result, the first cylindrical lens 110 can be made smaller. That is, even if the first cylindrical lens 110 is small, the amount of first laser light L1001 incident on the first cylindrical lens 110 can be increased. Furthermore, the beam width Wf in the fast axis direction of the first laser light L1001 emitted from the first cylindrical lens 110 can be narrowed. This allows the first laser light L1001 with a narrow beam width Wf to be incident on the incident surface 1131 of the laser crystal 1130. This makes it possible to increase the light density in the pumping region M1, and as a result, the laser light densities of the second laser beam L1002 and the output beam L1100 can be increased.

[0330] Because the first cylindrical lens 110 is bonded to the upper surface of the support member 1120j, the generatrix 115 of the first cylindrical lens 110 is parallel to the upper surface of the support member 1120j and parallel to the xy plane. That is, in this embodiment, the generatrix 115 and the active layer 200a are parallel, and the angle θ between the generatrix 115 and the active layer 200a satisfies |θ|<22.5°. More specifically, θ=0°.

[0331] Here, attention is focused on a plane parallel to the xy plane or a plane tilted in a direction rotated around the y axis from the xy plane. In this embodiment, the active layer 200a is a plane parallel to the xy plane, and the generatrix 115 is parallel to the xy plane.

[0332] Furthermore, the upper surface 301Tj of the fixing member 1300j, which is the first installation plane, and the lower surface 1125j of the supporting member 1120j, which is the first installation plane, are parallel to each other and are planes that are inclined in a direction rotated around the y-axis from the xy plane.

[0333] As described above, the angle θ satisfies θ=0°. The angle β formed between the generating line 115 and the first installation plane (upper surface 301Tj) satisfies 0°<|β|<45°. More specifically, the angle β satisfies 0°<|β|<22.5°. The generating line 115 is inclined with respect to the upper surface 301Tj, which is the first installation plane, and is inclined with respect to the lower surface 1125j, which is the first installation plane.

[0334] Then, in the first alignment step, the position of optical member 1600j is adjusted. Note that the first alignment step is performed after laser crystal 1130 and fixing member 1300j are fixed to upper surface 251T.

[0335] Therefore, as described in the second embodiment, when the first cylindrical lens 110, the support member 1120j, and the lower surface 1125j move in the x-axis direction by the amount Δx, the position of the generatrix 115 overlapping with the position of the light-emitting region 201 moves in the z-axis direction by the amount Δz. At this time, the absolute value of the amount Δz can be made sufficiently small relative to the absolute value of the amount Δx. In other words, the absolute value of the amount Δz is always smaller than the absolute value of the amount Δx. Therefore, when the positions of the first cylindrical lens 110, the support member 1120j, and the lower surface 1125j in the x-axis direction are adjusted by manufacturing equipment, the positions in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the positions in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130.

[0336] Here, the position adjustment of the optical member 1600j according to this embodiment will be described with reference to FIGS.

[0337] Fig. 32 is a side view of a light source module 1010j according to this embodiment, in which the support member 1120j is omitted.

[0338] In the light source module 1010j shown in Fig. 32, the emission direction d1, the first light ray LA1, and the second optical axis LA2 are aligned in a straight line. In this case, the overlap between the pumping region M1 and the resonator mode region M2 is large, so laser oscillation occurs efficiently in the laser crystal 1130. In Fig. 32, the overlap between the pumping region M1 and the resonator mode region M2 is indicated by hatching.

[0339] FIG. 33 is a first example of another side view of a light source module 1010j according to the present embodiment.

[0340] 33 shows the light source module 1010j after the positions of the first cylindrical lens 110, the support member 1120j, and the bottom surface 1125j have been moved because the second optical axis LA2 was located on the positive side of the z-axis relative to the emission direction d1. In this case, the positions of the first cylindrical lens 110, the support member 1120j, and the bottom surface 1125j are moved in the negative direction of the x-axis. As a result, as shown in FIG. 33, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 of the first cylindrical lens 110 is positioned in the positive direction of the z-axis relative to the position of the light-emitting region 201 and the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels at an inclination toward the positive side of the z-axis and is incident on the incident surface 1131 of the laser crystal 1130. The first light ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in Fig. 33, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130.

[0341] FIG. 34 is a second example of a side view of a light source module 1010j according to the present embodiment.

[0342] 34 shows the light source module 1010j after the positions of the first cylindrical lens 110, the support member 1120j, and the bottom surface 1125j have been moved because the second optical axis LA2 was located on the negative side of the z-axis relative to the emission direction d1. In this case, the positions of the first cylindrical lens 110, the support member 1120j, and the bottom surface 1125j are moved in the positive direction of the x-axis. As a result, as shown in FIG. 34, in the fast axis direction of the light-emitting region 201, the position of the generatrix 115 of the first cylindrical lens 110 is positioned in the negative direction of the z-axis relative to the position of the light-emitting region 201 and the emission direction d1. As a result, the first ray LA1 of the first laser beam L1001 emitted from the first cylindrical lens 110 travels at an angle inclined toward the negative side of the z-axis and is incident on the incident surface 1131 of the laser crystal 1130. The first light ray LA1 is then guided to the vicinity of the second optical axis LA2 within the laser crystal 1130 near the incident surface 1131. As a result, as shown in Fig. 34, the overlap between the pumping region M1 and the resonator mode region M2 becomes large, and laser oscillation occurs efficiently in the laser crystal 1130.

[0343] The following describes Modification 1 of Embodiment 3. The following description will focus on the differences from Embodiment 3, and the description of the commonalities will be omitted or simplified.

[0344] [Modification 1 of the Third Embodiment] FIG. 35 is a perspective view showing the configuration of a light source module 1010k according to the first modification of the third embodiment.

[0345] Light source module 1010k according to this modification has the same configuration as light source module 1010j according to the third embodiment, except that it includes nonlinear optical crystal 170. Light source module 1010k is a laser diode pumped solid-state laser, and further includes nonlinear optical crystal 170, thereby enabling it to emit harmonic laser light to light source module 1010j.

[0346] Output mirror 160 according to this modification has reflective film 161d. As in the fourth modification of the first embodiment, nonlinear optical crystal 170 is disposed between the optical element (laser crystal 1130) and the second optical filter (output mirror 160). This allows output light L1100 to be converted into third laser light L1003 that has passed through output mirror 160 (reflective film 161d).

[0347] FIG. 36 is a perspective view showing the configuration of a module package 1020 according to this modification.

[0348] The module package 1020 is a package that includes a light source module 1010k and an airtight package 1500.

[0349] The airtight package 1500 includes a lid 1504, a case 501, and a light-transmitting window unit 1505. The case 501 includes lead pins 522, a frame 503, and a bottom plate 502.

[0350] The airtight package 1500 has a space for accommodating the light source module 1010k. The space for accommodating the light source module 1010k is hermetically sealed, and the airtight package 1500 hermetically seals the light source module 1010k.

[0351] The frame 503 is disposed perpendicular to the bottom plate 502 of the case 501. The frame 503 surrounds the light source module 1010k and other components. A pair of lead pins 522 are inserted through the frame 503, and the pair of lead pins 522 electrically connect the outside and the inside of the case 501. The frame 503 has a frame-like and rectangular shape in a plan view, and is made of, for example, Cu, a Cu alloy, an Fe-Ni-Co alloy, or Al. The bottom plate 502 is made of, for example, Cu, a Cu alloy, Al, or a ceramic having high thermal conductivity (for example, AlN or BeO). The lid 1504 is a member that covers the upper part of the case 501, and is made of, for example, an inorganic material such as a metal or ceramic material. The lid 1504 is rectangular in a plan view, and covers the entire upper surface of the frame 503.

[0352] The light-transmitting window unit 1505 is a unit that transmits the output light L1100 and is provided in the frame body 503. That is, the output light L1100 is output from the inside of the case 501 to the outside through the light-transmitting window unit 1505.

[0353] If foreign matter such as dirt adheres to components of the light source module 1010k, such as the semiconductor laser element 200, the performance of the emitted output light L1100 may be degraded. However, by hermetically sealing the light source module 1010k with the airtight package 1500, the semiconductor laser element 200 and the like are protected from foreign matter such as dirt, and degradation of the performance of the emitted output light L1100 is suppressed.

[0354] [Effects, etc.] In the light source module 1010k according to the first modification of the third embodiment, the semiconductor laser device 200 and the optical element are hermetically sealed in an airtight package 1500.

[0355] This protects the semiconductor laser device 200 and the optical elements from foreign matter such as dirt, thereby suppressing degradation in the performance of the emitted output light L1100.

[0356] Light source module 1010k according to the first modification of the third embodiment further includes nonlinear optical crystal 170. Nonlinear optical crystal 170 is hermetically sealed in hermetic package 1500.

[0357] This protects nonlinear optical crystal 170 from foreign matter such as dirt, thereby suppressing degradation in the performance of emitted output light L1100.

[0358] (Fourth embodiment) The following describes embodiment 4. The following mainly describes the differences from embodiment 3, and the description of commonalities will be omitted or simplified.

[0359] FIG. 37 is a perspective view showing the configuration of a light source module 1010m according to the fourth embodiment.

[0360] Light source module 1010m according to the present embodiment has the same configuration as light source module 1010j according to embodiment 3, except that it includes optical member 1600m instead of optical member 1600j and does not include fixing member 1300j. Light source module 1010m is a laser diode pumped solid-state laser.

[0361] The optical member 1600m according to this embodiment includes a first cylindrical lens 110, a support member 1120m, and a first installation plane. In this embodiment, the light source module 1010m includes a laser crystal 1130 and a terminal mirror 1140.

[0362] The support member 1120m is a member having a first support member 1121m and a second support member 1122m.

[0363] The first support member 1121m is a member that is joined to the fixed base 1250 and the second support member 1122m and supports the second support member 1122m.

[0364] The first support member 1121m is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The first support member 1121m has an upper surface on the positive side of the z-axis and a lower surface 1125m on the negative side of the z-axis. The lower surface 1125m of the first support member 1121m is a plane parallel to the xy plane, and the upper surface of the first support member 1121m is a plane tilted in a direction rotated around the y-axis from the xy plane.

[0365] The first support member 1121m is placed in a placement area 131 provided on the upper surface 251T. In this embodiment, the upper surface 251T corresponds to a first flat installation surface, and the lower surface 1121m corresponds to a first installation flat surface.

[0366] The second support member 1122m is a member that is bonded to the first support member 1121m and the first cylindrical lens 110, and supports the first cylindrical lens 110.

[0367] The second support member 1122m is a member having a flat plate shape. The second support member 1122m has an upper surface on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The upper and lower surfaces of the second support member 1122m are planes that are inclined in a direction rotated around the y-axis from the xy plane.

[0368] The second support member 1122m and the first cylindrical lens 110 are bonded together, more specifically, the upper surface of the second support member 1122m and the lower surface of the first cylindrical lens 110 are parallel and bonded together. Also, the second support member 1122m and the first support member 1121m are bonded together, more specifically, the lower surface of the second support member 1122m and the upper surface of the first support member 1121m are parallel and bonded together.

[0369] The first support member 1121m and the second support member 1122m of the support member 1120m are made by the same processing as the support member 1120 described in the first embodiment, and are made of the same material.

[0370] Here, attention is focused on a plane parallel to the xy plane or a plane tilted in a direction rotated from the xy plane around the y-axis. In this embodiment, the upper surface 251T of the fixed base 1250, the active layer 200a, and the lower surface 1125m of the first support member 1121m are planes parallel to the xy plane. In addition, the upper surface of the first support member 1121m and the upper and lower surfaces of the second support member 1122m are planes tilted in a direction rotated from the xy plane around the y-axis and are parallel to each other.

[0371] Because the first cylindrical lens 110 is bonded to the upper surface of the second support member 1122m, the generatrix 115 of the first cylindrical lens 110 is parallel to the upper surface of the second support member 1122m and is tilted in a direction rotated around the y-axis from the xy plane. That is, in this embodiment, because the generatrix 115 is tilted with respect to the active layer 200a, the angle θ between the generatrix 115 and the active layer 200a satisfies 0°<|θ|<22.5°.

[0372] Furthermore, the angle formed between the generatrix 115 and the first installation plane (upper surface 251T) is defined as angle β. The angle β in this embodiment satisfies 0°<|β|<45°. The angle β is equal to the angle θ. In the above, the first laser light L1001 emitted from the semiconductor laser element 200 is incident on the first cylindrical lens 110. Then, the first laser light L1001, whose divergence angle has been changed, is emitted from the first cylindrical lens 110 in a direction according to the position of the generatrix 115, and is incident on the incident surface 1131 of the laser crystal 1130.

[0373] Then, in the first alignment step, the position of optical member 1600m is adjusted. Note that the first alignment step is performed after laser crystal 1130 is fixed to upper surface 251T.

[0374] Therefore, as described in the first embodiment, when the first cylindrical lens 110, the support member 1120m, and the lower surface 1125m move by a movement amount Δx in the x-axis direction, the position of the generatrix 115 overlapping with the position of the light-emitting region 201 moves by a movement amount Δz in the z-axis direction. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the positions of the first cylindrical lens 110, the support member 1120m, and the lower surface 1125m in the x-axis direction are adjusted by manufacturing equipment, the positions in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the positions in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. This increases the overlap between the excitation region M1 and the resonator mode region M2, thereby enabling efficient laser oscillation in the laser crystal 1130.

[0375] (Embodiment 5) The following describes embodiment 5. The following description focuses on the differences from embodiment 3, and the description of commonalities will be omitted or simplified.

[0376] [composition] Fig. 38A is a side view showing the configuration of a light source module 1010n according to embodiment 5. Fig. 38B is a top view showing the configuration of a light source module 1010n according to embodiment 5.

[0377] Light source module 1010n according to the present embodiment has the same configuration as light source module 1010j according to the third embodiment, except that it does not include laser crystal 1130, terminating mirror 1140, and output mirror 160, it includes diffractive optical element 180 and a third flat installation surface, and the rear end face of semiconductor laser element 200 is terminating mirror 200b. Light source module 1010n according to the present embodiment also differs from light source module 1010j according to the third embodiment in that it does not include second optical axis LA2 and has grating direction 180a.

[0378] The diffractive optical element 180 is an example of an optical element and a second optical filter. That is, the diffractive optical element 180 is both an optical element and a second optical filter. The end mirror 200b and the diffractive optical element 180 constitute an optical system 290b, which is a resonator optical system. The light source module 1010n is an external cavity type laser diode.

[0379] The diffractive optical element 180 is, for example, a surface relief diffraction grating or a volume holographic diffraction grating (VHG), but is not limited to these. Volume holographic grating is also called volume Bragg grating (VBG). The diffractive optical element 180 has a grating direction 180a and emits diffracted light according to the wavelength and incident angle of the incident light. In this embodiment, the diffractive optical element 180 is a volume holographic diffraction grating in which layers whose refractive indexes vary periodically are stacked. The grating direction 180a is a direction perpendicular to the stacked surface, which is the grating surface. The diffractive optical element 180 has a rectangular parallelepiped shape and has a bottom surface 180B facing a top surface 251T of the fixed base 1250. The diffractive optical element 180 is placed in an arrangement region 281 provided on the top surface 251T.

[0380] The rear end facet of semiconductor laser device 200 according to this embodiment is terminating mirror 200b. Terminating mirror 200b reflects first laser beam L1001. Terminating mirror 200b may be configured to reflect first laser beam L1001, and may be configured, for example, by a dielectric multilayer film on the rear end facet of semiconductor laser device 200.

[0381] The emission surface of the light emitting region 201 of the semiconductor laser element 200 is a low-reflectivity surface having a reflectivity of, for example, less than 1% for the wavelength of the first laser beam L1001. The first laser beam L1001 emitted from the semiconductor laser element 200 is incident on the first cylindrical lens 110. The first laser beam L1001 emitted from the first cylindrical lens 110 is incident on the incident surface 181 of the diffractive optical element 180, which is the surface facing the semiconductor laser element 200.

[0382] The diffractive optical element 180 reflects light of a portion of wavelengths of the first laser light L1001 incident on the diffractive optical element 180 that meets the Bragg reflection condition of the diffraction grating formed on the diffractive optical element 180, and transmits light of the other wavelengths. Here, by having the first ray LA1 of the first laser light L1001 incident on the diffractive optical element 180 parallel to the grating direction 180a, the Bragg reflection condition of the diffraction grating is met in the grating direction 180a, and the light of the portion of wavelengths is reflected. The reflected light of the portion of wavelengths is incident on the first cylindrical lens 110 and then emitted from the first cylindrical lens 110 and returns to the light-emitting region 201. The light of the portion of wavelengths is amplified by the optical system 290b of the resonator optical system, which is composed of the terminal mirror 200b and the diffractive optical element 180. This makes the light source module 1010n an external resonance type laser module that performs laser oscillation using light of the portion of wavelengths. The first laser beam L1001 that has passed through the diffractive optical element 180 is output as output beam L1100B with a fixed peak wavelength. The peak wavelength of the first laser beam L1001 changes by approximately 1 nm when the temperature of the fixing base 1250 that fixes the semiconductor laser element 200 changes by approximately 10°C. However, by using the diffractive optical element 180 to cause external resonance, the change in the peak wavelength of the output beam L1100B can be kept to 0.1 nm or less. Note that the output beam L1100B with a fixed peak wavelength refers to the output beam L1100B whose peak wavelength changes by 0.1 nm or less with respect to the temperature of the semiconductor laser element 200 within a predetermined temperature range. As shown in FIG. 38B, the diffractive optical element 180 is a slant-type diffraction grating in which the grating plane of the diffraction grating is inclined with respect to the surface of the diffractive optical element 180 when viewed from above. The diffractive optical element 180 is arranged so that the grating direction 180a of the diffractive optical element 180 is parallel to the first light ray LA1 of the first laser light L1001. As a result, light of a portion of the wavelengths that satisfies the Bragg reflection condition of the diffraction grating in the grating direction 180a and is reflected enters the first cylindrical lens 110, and is further emitted from the first cylindrical lens 110 and returns to the light-emitting region 201.At this time, since the incident surface 181 of the diffractive optical element 180 is inclined from a direction perpendicular to the traveling direction of the first laser light L1001, the laser light of the first laser light L1001 reflected by the surface of the diffractive optical element 180 does not return to the light-emitting region 201.

[0383] As in the third embodiment, in this embodiment, the lower surface 1125j corresponds to the first installation plane, the upper surface 301Tj corresponds to the first installation plane, the lower surface 180B corresponds to the third installation plane, and the upper surface 251T corresponds to the third installation plane.

[0384] As in the third embodiment, the angle θ satisfies θ=0°. The angle β formed between the bus 115 and the first installation plane (upper surface 301Tj) satisfies 0°<|β|<45°. More specifically, the angle β satisfies 0°<|β|<22.5°.

[0385] In this embodiment, the light source module 1010n does not include the output mirror 160, and therefore the manufacturing method does not include the second placement step, second alignment step, and second fixing step, which use the output mirror 160. In the first alignment step, the position of the optical member 1600j is adjusted. Note that the first alignment step is performed after the diffractive optical element 180 and the fixing member 1300j are fixed to the upper surface 251T.

[0386] Therefore, as in the third embodiment, when the optical element 1600j (first cylindrical lens 110, support member 1120j, and lower surface 1125j) moves by the movement amount Δx in the x-axis direction during the first alignment step, the position of the generatrix 115 that overlaps with the position of the light-emitting region 201 moves by the movement amount Δz in the z-axis direction. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. In other words, the absolute value of the movement amount Δz is always smaller than the absolute value of the movement amount Δx. Therefore, when the positions of the first cylindrical lens 110, support member 1120j, and lower surface 1125j in the x-axis direction are adjusted by manufacturing equipment, the positions in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the positions in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. In this embodiment, it is easy to adjust the position of the first cylindrical lens 110 so that the first ray LA1 of the first laser beam L1001 and the grating direction 180a are parallel in the fast axis direction. As a result, of the first laser beam L1001 incident on the diffractive optical element 180, light of a portion of the wavelength that meets the Bragg reflection condition of the diffraction grating can be reflected by the diffractive optical element 180 and incident on the light-emitting region 201. This makes it easy to realize the light source module 1010n, which is an external resonance type laser module. Furthermore, in this embodiment, it is possible to set the wavelength of the output beam L1100B to a specific wavelength. In this embodiment, the wavelength of the output beam L1100B is 443.8 nm.

[0387] Fig. 39 is another first example of a side view of the light source module 1010n according to the present embodiment. Fig. 40 is another second example of a side view of the light source module 1010n according to the present embodiment.

[0388] Fig. 39 shows an example in which the first cylindrical lens 110 is shifted in the positive direction of the z axis, and the generatrix 115 is located on the positive side of the z axis relative to the emission direction d1, so the first light ray LA1 travels at an inclination in the positive direction of the z axis. Fig. 40 shows an example in which the first cylindrical lens 110 is shifted in the negative direction of the z axis, and the generatrix 115 is located on the negative side of the z axis relative to the emission direction d1, so the first light ray LA1 travels at an inclination in the negative direction of the z axis.

[0389] In the example shown in FIGS. 39 and 40 , the first light ray LA1 of the first laser light L1001 incident on the diffractive optical element 180 is not parallel to the grating direction 180a. Therefore, when the wavelength of the first laser light L1001 satisfies the Bragg reflection condition for the grating direction 180a in the diffraction grating formed in the diffractive optical element 180, there is no light with a wavelength that meets the Bragg reflection condition, and the first laser light L1001 is transmitted through the diffractive optical element 180. In other words, some wavelengths of the first laser light L1001 are not reflected by the diffractive optical element 180 and return to the light-emitting region 201. Therefore, the example shown in FIGS. 39 and 40 cannot realize an externally resonated laser module. Therefore, the peak wavelength of the output light L1100C, which is the light transmitted through the diffractive optical element 180, is not fixed. Specifically, the peak wavelength of the output light L1100C, which is the light transmitted through the diffractive optical element 180, changes depending on the temperature of the fixing base 1250. However, as described above, the light source module 1010n can move the optical element 1600j, and therefore can change from the state shown in Figures 39 and 40 to the state shown in Figures 38A and 38B, making it easy to realize the light source module 1010n, which is an external resonance type laser module.

[0390] In the manufacturing method of this embodiment, the first alignment step is performed after the diffractive optical element 180 and the fixing member 1300j are fixed to the upper surface 251T, but this is not limited to this. The diffractive optical element 180 may be used instead of the output mirror 160, and the second placement step, second alignment step, and second fixing step may be performed. In this case, in the first placement step, the optical element 1600j is placed on the upper surface 301Tj of the fixing member 1300j. In the second placement step, the diffractive optical element 180 is placed in the placement region 281 on the upper surface 251T of the fixing base 1250. In the first alignment step, the optical element 1600j is moved across the upper surface 301Tj, thereby moving and adjusting the generatrix 115 in the z-axis direction. In the second alignment step, as shown by the dashed arrow in Fig. 38B, the upper surface 251T of the diffractive optical element 180 is slightly rotated in the z-axis direction, thereby adjusting the first light ray LA1 and the grating direction 180a to be parallel when viewed from the z-axis direction. That is, the third installation plane (lower surface 180B) of the diffractive optical element is moved along the third installation plane (upper surface 251T) for adjustment. In the first fixing step, the optical member 1600j is fixed to the fixing member 1300j and fixed to the fixing base 1250. In the second fixing step, the diffractive optical element 180 is fixed to the fixing base 1250. A light source module 1010n may be manufactured using the above manufacturing method.

[0391] Note that, hereinafter, the first placement step, first alignment step, and first fixing step according to this embodiment may be simply referred to as a placement step of placing optical element 1600j, an alignment step of adjusting the position of optical element 1600j, and a fixing step of fixing optical element 1600j, respectively. Similarly, the second placement step, second alignment step, and second fixing step according to this embodiment may be simply referred to as a placement step of placing diffractive optical element 180, an alignment step of adjusting the position of diffractive optical element 180, and a fixing step of fixing diffractive optical element 180, respectively.

[0392] The following describes Modification 1 of Embodiment 5. The following description will focus on the differences from Embodiment 5, and the description of the commonalities will be omitted or simplified.

[0393] [Modification 1 of the Fifth Embodiment] FIG. 41 is a side view showing the configuration of a light source module 1010p according to the first modification of the fifth embodiment.

[0394] Light source module 1010p according to this modification has the same configuration as light source module 1010n according to embodiment 5, except that it further includes laser crystal 1130, terminating mirror 1140, and output mirror 160. In light source module 1010p according to this modification, optical system 290 includes second optical axis LA2. Light source module 1010p is a laser diode pumped solid-state laser.

[0395] The behavior of light in this modified example is as follows. As described in the fifth embodiment, first laser beam L1001 passes through diffractive optical element 180. First laser beam L1001 (output beam L1100B) that has passed through diffractive optical element 180 passes through terminal mirror 1140 and is incident on incident surface 1131 of laser crystal 1130. Then, as described in the first embodiment, output beam L1100B that has entered laser crystal 1130 is converted by laser crystal 1130 into second laser beam L1002, which is incident on output mirror 160. Then, second laser beam L1002 that has passed through output mirror 160 (reflecting film 161) is emitted as output beam L1100. Furthermore, as described in the fifth embodiment, by adjusting the position of the optical member 1600j in the first alignment step and adjusting the position of the diffractive optical element 180 in the second alignment step, it is possible to easily realize the light source module 1010p, which is a module that combines an external resonance laser module with a solid-state laser. That is, by aligning the first light beam LA1 and the grating direction 180a parallel to each other, it is possible to realize an external resonance laser module. Furthermore, by overlapping the first light beam LA1 emitted from the diffractive optical element 180 with the second optical axis LA2, the overlap between the excitation region M1 and the resonator mode region M2 is increased, thereby efficiently generating laser oscillation in the laser crystal 1130. Furthermore, in addition to the first alignment step and the second alignment step, a third alignment step of adjusting the position of the output mirror 160 and a third fixation step of fixing the output mirror 160 may be performed. That is, the second installation plane (lower surface 160B) of output mirror 160 is moved and adjusted along the second installation plane (upper surface 251T in placement region 261). The third alignment step and third fixing step are the same as the second alignment step and second fixing step in embodiment 1. Also in this embodiment, the first light ray LA1 emitted from diffractive optical element 180 is guided to the vicinity of second optical axis LA2 within laser crystal 1130 near incident surface 1131. As a result, the overlap between excitation region M1 and resonator mode region M2 becomes large, and laser oscillation occurs efficiently in laser crystal 1130.

[0396] Furthermore, optical system 290b, which is composed of diffractive optical element 180 and terminating mirror 200b, makes it possible to set the wavelength of first laser beam L1001 (output beam L1100B) to a specific wavelength. For example, since the wavelength of output beam L1100B can be matched to the absorption peak wavelength of laser crystal 1130, laser crystal 1130 can further efficiently emit second laser beam L1002. In other words, output beam L1100 can be efficiently emitted.

[0397] [Effects, etc.] In the light source module 1010n according to the fifth embodiment, the optical element is a diffractive optical element 180.

[0398] As a result, as explained above, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing equipment accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing equipment accuracy. In other words, a light source module 1010n is realized that can be positioned with high accuracy. Therefore, it is possible to easily realize a light source module 1010n that is an external cavity laser module. In addition, it is possible to set the wavelength of the output light L1100B to a specific wavelength.

[0399] In the light source module 1010n according to the fifth embodiment, the diffractive optical element 180 is a volume holographic diffraction grating.

[0400] This makes it possible to realize a light source module 1010n that includes a volume holographic diffraction grating as the diffractive optical element 180.

[0401] (Sixth embodiment) The following describes embodiment 6. The following description focuses on the differences from embodiment 5, and the description of commonalities will be omitted or simplified.

[0402] FIG. 42 is a side view showing the configuration of a light source module 1010q according to the sixth embodiment.

[0403] Light source module 1010q according to the present embodiment has the same configuration as light source module 1010n according to embodiment 5, mainly except that light source module 1010q includes optical member 1600q instead of optical member 1600j and does not include fixing member 1300j. Light source module 1010q is an external cavity laser diode.

[0404] The optical member 1600q includes a first cylindrical lens 110, a support member 1120, a diffractive optical element 180, and a first installation plane.

[0405] In the first embodiment, it has been described that the support member 1120 is bonded to the end mirror 1140, but in the present embodiment, it is bonded to the diffractive optical element 180. More specifically, the plane on the y-axis positive side of the diffractive optical element 180 and the plane on the y-axis negative side of the support member 1120 are bonded together. Therefore, the first cylindrical lens 110 is fixed to the diffractive optical element 180, which is an optical element. In this way, the support member 1120 differs from the first embodiment in that it is fixed to the diffractive optical element 180 rather than the end mirror 1140.

[0406] The diffractive optical element 180 is provided on the upper surface 251T. The diffractive optical element 180 has a lower surface 180B. The lower surface 180B is a plane parallel to the upper surface 251T, that is, a plane parallel to the xy plane.

[0407] In this embodiment, the first installation plane of the optical member 1600q is the lower surface 180B of the diffractive optical element 180. The first installation plane is the upper surface 251T.

[0408] Here, attention is focused on a plane parallel to the xy plane or a plane tilted in a direction rotated around the y-axis from the xy plane. In this embodiment, the upper surface 251T of the fixed base 1250, the active layer 200a, the lower surface 180B of the diffractive optical element 180, and the lower surface of the support member 1120 are planes parallel to the xy plane. In addition, the upper surface of the support member 1120 is a plane tilted in a direction rotated around the y-axis from the xy plane.

[0409] Since the first cylindrical lens 110 is bonded to the upper surface of the support member 1120, the generatrix 115 of the first cylindrical lens 110 is parallel to the upper surface of the support member 1120 and is inclined in a direction rotated around the y-axis from the xy plane. That is, in this embodiment, the generatrix 115 is inclined in a direction rotated around the y-axis from the upper surface 251T, which is the first installation plane, the active layer 200a, and the xy plane.

[0410] Here, the angle θ formed between the busbar 115 and the active layer 200a satisfies |θ|<22.5°. In this embodiment, since the busbar 115 is inclined with respect to the active layer 200a, the angle θ satisfies 0°<|θ|<22.5°.

[0411] Moreover, the angle β formed between the bus line 115 and the first installation plane satisfies 0°<|β|<45° and is equal to the angle θ.

[0412] Then, in the first alignment step, the position of the first cylindrical lens 110 is adjusted by moving the optical member 1600q in the x-axis direction.

[0413] Therefore, as described in the fifth embodiment, when optical element 1600q moves in the x-axis direction by a movement amount Δx, the position of generatrix 115, which overlaps with the position of light-emitting region 201, moves in the z-axis direction by a movement amount Δz. At this time, the absolute value of the movement amount Δz can be made sufficiently small relative to the absolute value of the movement amount Δx. Therefore, when the position of optical element 1600q in the x-axis direction is adjusted by a manufacturing facility, the position in the x-axis direction can be adjusted with an accuracy equal to the manufacturing facility accuracy, and the position in the z-axis direction can be adjusted with an accuracy higher than the manufacturing facility accuracy. In this embodiment, it is easy to adjust the position of first cylindrical lens 110 so that, of the first laser beam L1001 incident on incidence surface 181 of diffractive optical element 180, light of a certain wavelength that meets the Bragg reflection condition of the diffraction grating is reflected by diffractive optical element 180 and enters light-emitting region 201. This makes it easy to realize light source module 1010q, which is an external resonance laser module, and to set the oscillation wavelength of output light L1100B to a specific wavelength.

[0414] In this embodiment, the lower surface 180B may be the third installation plane, and the upper surface 251T may be the third installation plane. That is, in a first alignment step, the position of the first cylindrical lens 110 may be adjusted by moving the optical member 1600q in the x-axis direction, and then in a second alignment step, the position of the diffractive optical element 180 may be adjusted by moving the optical member 1600q in a rotational direction with respect to the z-axis direction on the upper surface 251T.

[0415] In the following, the first placement step and the first fixing step according to this embodiment may be simply referred to as a placement step of placing the optical member 1600q and a fixing step of fixing the optical member 1600q, respectively. Also, the first alignment step and the second alignment step according to this embodiment may be simply referred to as an alignment step of adjusting the position of the optical member 1600q.

[0416] The following describes Modification 1 of Embodiment 6. The following description will focus on the differences from Embodiment 6, and the description of the commonalities will be omitted or simplified.

[0417] [Modification 1 of the Sixth Embodiment] FIG. 43 is a side view showing the configuration of a light source module 1010r according to the first modification of the sixth embodiment.

[0418] Light source module 1010r according to this modification has the same configuration as light source module 1010q according to the sixth embodiment, except that it further includes laser crystal 1130, terminating mirror 1140, and output mirror 160.

[0419] The behavior of light in this modified example is as follows. First laser beam L1001 is incident on incident surface 181 of diffractive optical element 180 and then passes through diffractive optical element 180. Having passed through diffractive optical element 180, first laser beam L1001 passes through terminal mirror 1140 and enters laser crystal 1130. As described in the first embodiment, first laser beam L1001 that has entered laser crystal 1130 is converted by laser crystal 1130 into second laser beam L1002, which then enters output mirror 160. Second laser beam L1002 that has passed through output mirror 160 (reflecting film 161) is then emitted as output beam L1100. Furthermore, by adjusting the position of optical member 1600q in the first alignment step and the second alignment step as described in the sixth embodiment, light source module 1010r, which is a module combining an external cavity laser module with a solid-state laser, can be easily realized, and the wavelength of first laser beam L1001 (output beam L1100B) transmitted through diffractive optical element 180 can be set to a specific wavelength. For example, since the wavelength of first laser beam L1001 (output beam L1100B) transmitted through diffractive optical element 180 can be matched to the absorption peak wavelength of laser crystal 1130, laser crystal 1130 can efficiently emit second laser beam L1002. In other words, output beam L1100 can be efficiently emitted. Furthermore, as in the first modification of the fifth embodiment, steps of adjusting the position of output mirror 160 and fixing it may be performed as the third alignment step and the third fixing step.

[0420] (Embodiment 7) The seventh embodiment will be described below. The following description will focus on the differences from the fifth embodiment, and the description of the commonalities will be omitted or simplified.

[0421] FIG. 44 is a side view showing the configuration of a light source module 1010s according to the seventh embodiment.

[0422] Light source module 1010s according to the present embodiment has the same configuration as light source module 1010n according to embodiment 5, except that it further includes laser crystal 1130, terminating mirror 1140, output mirror 160, fixing member 1300s, and a fourth flat installation surface, and that it also includes optical members 1600j and 1600s. Light source module 1010s is a laser diode pumped solid-state laser.

[0423] The optical member 1600s includes a third cylindrical lens 106, a support member 1120s, and a fourth installation plane.

[0424] In this embodiment, the fixing member 1300 s, the support member 1120 s, and the third cylindrical lens 106 are placed between the laser crystal 1130 and the end mirror 1140 and the diffractive optical element 180 .

[0425] The third cylindrical lens 106 is a lens disposed between the diffractive optical element 180 and the laser crystal 1130. That is, the first laser light L1001 emitted from the diffractive optical element 180 is incident on the third cylindrical lens 106. The first laser light L1001 emitted from the third cylindrical lens 106 is incident on the laser crystal 1130.

[0426] The third cylindrical lens 106 changes the divergence angle of the first laser beam L1001 in the fast axis direction. For example, the third cylindrical lens 106 changes the divergence angle of the first laser beam L1001 in the fast axis direction so that it becomes smaller, that is, the third cylindrical lens 106 emits the first laser beam L1001 with a small divergence angle in the fast axis direction.

[0427] The divergence angle of the first laser beam L1001 emitted from the third cylindrical lens 106 in the fast axis direction is, for example, between −1° and +1°. Angle angles with a negative sign indicate convergence. The third cylindrical lens 106 is a lens that quasi-collimates the first laser beam L1001 in the fast axis direction.

[0428] The third cylindrical lens 106 is an optical component having a power axis (refractive power) and a non-power axis. The power axis and the non-power axis are disposed perpendicular to each other. That is, the third cylindrical lens 106 has a third cylindrical surface. The third cylindrical lens 106 has a cylindrical surface that is convexly curved toward the power axis, i.e., the surface of a convex cylinder. The third cylindrical lens 106 is a convex cylindrical lens. The power axis is inclined with respect to the fast axis of the first laser light L1001.

[0429] The third cylindrical lens 106 has an incident surface onto which the first laser beam L1001 is incident and an exit surface from which the laser beam is emitted. In this embodiment, the third cylindrical lens 106 is a plano-convex cylindrical lens with a flat incident surface and a convex exit surface. In this embodiment, the incident surface is a surface parallel to the zx plane. The exit surface is a third cylindrical surface, which is a convex surface whose curved surface is expressed by a spherical function or an aspherical function. The power axis is an axis parallel to the zx plane and inclined with respect to the z axis. Note that in this embodiment, a plano-convex cylindrical lens is used as the third cylindrical lens 106. However, a biconvex cylindrical lens, such as a convex meniscus cylindrical lens with one side convex and the other concave, may also be used.

[0430] The third cylindrical lens 106 is a member made of an inorganic transparent material such as glass, and has an anti-reflection coating film that matches the wavelength of the first laser light L1001 formed on the incident surface and the exit surface for the first laser light L1001.

[0431] Furthermore, the generatrix 115s of the third cylindrical lens 106 will be described.

[0432] The third cylindrical lens 106 is a cylindrical lens having a third cylindrical surface. The third cylindrical surface has a generatrix 115s. The emission surface of the third cylindrical lens 106 is a convex third cylindrical surface. Generally, a generatrix is a straight line at each position when the cylindrical surface (curved surface) of the third cylindrical surface is formed by moving a straight line (when drawn by moving a straight line). Of the countless generatrixes, the generatrix 115s is a straight line that follows the convex vertex of the surface of the convex cylinder.

[0433] In this embodiment, the generatrix 115s of the third cylindrical lens 106 is parallel to the xy plane.

[0434] Next, the fixing member 1300s will be described.

[0435] The fixing member 1300s is a member that is joined to the support member 1120s and supports the support member 1120s.

[0436] The fixing member 1300s is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The fixing member 1300s has an upper surface 301Ts on the positive side of the z-axis and a lower surface on the negative side of the z-axis. The lower surface of the fixing member 1300s is a plane parallel to the xy plane, and the upper surface 301Ts of the fixing member 1300s is a plane inclined in a direction rotated around the y-axis from the xy plane. In this embodiment, this upper surface 301Ts corresponds to the fourth installation plane.

[0437] The fixing member 1300s is formed by processing a substrate made of a semiconductor material such as glass or silicon by partial etching, polishing, or cutting. The fixing member 1300s may be formed of a metal such as Fe or an Fe alloy, or a ceramic such as Al2O3, ZrO2, Si3N4, or AlN. The fixing member 1300s is disposed on the upper surface 251T.

[0438] Furthermore, the support member 1120s of the optical member 1600s will be described.

[0439] The support member 1120s is a member that is bonded to the third cylindrical lens 106 and supports the third cylindrical lens 106. The support member 1120s is made of the same material as the fixing member 1300s.

[0440] The support member 1120s is a member having the shape of a trapezoidal prism, with a surface trapezoidal when viewed from the y-axis direction. The support member 1120s has an upper surface on the positive side of the z-axis and a lower surface 1125s on the negative side of the z-axis. The upper surface of the support member 1120s is a plane parallel to the xy plane, and the lower surface 1125s of the support member 1120s is a plane tilted in a direction rotated around the y-axis from the xy plane.

[0441] The support member 1120s and the third cylindrical lens 106 are bonded together; more specifically, the upper surface of the support member 1120s and the lower surface of the third cylindrical lens 106 are parallel and bonded together by, for example, soldering or welding. The support member 1120s and the fixing member 1300s are bonded together; more specifically, the lower surface 1125s of the support member 1120s and the upper surface 301Ts of the fixing member 1300s are parallel and bonded together. In this embodiment, the lower surface 1125s corresponds to the fourth installation plane, and the upper surface 301Ts of the fixing member 1300s corresponds to the fourth installation plane. In the first alignment step, the third cylindrical lens 106 and the support member 1120s are moved so that the fourth installation plane (lower surface 1125s) is aligned with the fourth installation plane (upper surface 301Ts).

[0442] The support member 1120s is fabricated by the same processing as the support member 1120 described in the first embodiment, and is made of the same material.

[0443] Because the third cylindrical lens 106 is bonded to the upper surface of the support member 1120s, the generatrix 115s of the third cylindrical lens 106 is parallel to the upper surface of the support member 1120s and parallel to the xy plane. That is, in this embodiment, the generatrix 115s and the active layer 200a are parallel, and the angle formed between the generatrix 115s and the active layer 200a is, for example, the same as the angle θ, satisfying θ=0°.

[0444] Here, attention is focused on a plane parallel to the xy plane or a plane tilted in a direction rotated around the y axis from the xy plane. In this embodiment, the active layer 200a is a plane parallel to the xy plane, and the generatrix 115s is parallel to the xy plane.

[0445] Furthermore, the upper surface 301Ts of the fixing member 1300s, which is the fourth installation plane, and the lower surface 1125s of the support member 1120s, which is the fourth installation plane, are parallel to each other and are planes that are inclined in a direction rotated around the y-axis from the xy plane.

[0446] The angle formed between the bus 115s and the fourth installation plane (top surface 301Ts) is, for example, the same as angle β. In this embodiment, angle β also satisfies 0°<|β|<45°. More specifically, angle β satisfies 0°<|β|<22.5°.

[0447] Then, before the first arrangement step of arranging optical element 1600s, an arrangement step of arranging optical element 1600j shown in embodiment 5, an arrangement step of arranging diffractive optical element 180, an alignment step of adjusting the position of optical element 1600j, an alignment step of adjusting the position of diffractive optical element 180, a fixing step of fixing optical element 1600j, and a fixing step of fixing diffractive optical element 180 are performed. These six steps are performed before the first arrangement step of arranging optical element 1600s. In the first alignment step, the position of optical element 1600s is adjusted. Note that the first alignment step is performed after laser crystal 1130 and fixing member 1300s are fixed to upper surface 251T.

[0448] As described above, the angle between the generatrix 115s and the active layer 200a is, for example, the angle θ, and the angle between the generatrix 115s and the fourth installation plane (upper surface 301Ts) is, for example, the angle β. Therefore, when the optical element 1600s (the third cylindrical lens 106, the support member 1120s, and the lower surface 1125s) moves by the amount Δx in the x-axis direction, the position of the generatrix 115s that overlaps with the position of the light-emitting region 201 moves by the amount Δz in the z-axis direction. At this time, the absolute value of the amount Δz can be made sufficiently small relative to the absolute value of the amount Δx. In other words, the absolute value of the amount Δz is always smaller than the absolute value of the amount Δx. Therefore, when the positions of the third cylindrical lens 106, the support member 1120s, and the lower surface 1125s in the x-axis direction are adjusted by the manufacturing equipment, the positions in the x-axis direction can be adjusted with an accuracy equal to the accuracy of the manufacturing equipment, and the positions in the z-axis direction can be adjusted with an accuracy higher than the accuracy of the manufacturing equipment. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing efficient laser oscillation in the laser crystal 1130.

[0449] Furthermore, in this embodiment, as in the fifth embodiment, the positions of optical member 1600j (first cylindrical lens 110, support member 1120j, and lower surface 1125j) and diffractive optical element 180 are adjusted, that is, adjustment is made so that first laser light L1001 is amplified by optical system 290b, which is a resonator optical system. Furthermore, as in the third embodiment, the positions of optical member 1600s and output mirror 160 are adjusted, and adjustment is made so that second laser light L1002 is amplified by optical system 290, which is a resonator optical system. This makes it possible to easily realize light source module 1010s, which is a module combining an external resonance type laser module with a solid-state laser, and to set the wavelength of first laser light L1001 (output light L1100B) transmitted through diffractive optical element 180 to a specific wavelength. For example, since the wavelength of first laser beam L1001 (output beam L1100B) transmitted through diffractive optical element 180 can be matched to the absorption peak wavelength of laser crystal 1130, laser crystal 1130 can efficiently emit second laser beam L1002. In other words, output beam L1100 can be efficiently emitted.

[0450] (Embodiment 8) The following describes embodiment 8. The following mainly describes the differences from embodiment 6, and omits or simplifies the description of commonalities.

[0451] FIG. 45 is a side view showing the configuration of a light source module 1010t according to the eighth embodiment.

[0452] A light source module 1010t according to this embodiment has the same configuration as the light source module 1010q according to embodiment 6, except that it further includes an output mirror 160 and an optical member 1600t. The light source module 1010t is a laser diode pumped solid-state laser.

[0453] The optical member 1600t includes a third cylindrical lens 106, a laser crystal 1130, a terminal mirror 1140, and a fourth installation surface. The fixed base 1250 includes a fourth installation surface.

[0454] The third cylindrical lens 106 is bonded to the terminal mirror 1140 without a support member. Of the convex and flat surfaces of the third cylindrical lens 106, the flat surface is bonded to the terminal mirror 1140. In this embodiment, the entrance surface is a convex surface and the exit surface is a flat surface.

[0455] The generatrix 115s of the third cylindrical lens 106 according to this embodiment is inclined with respect to the first installation plane (upper surface 251T). The angle between the generatrix 115s and the active layer 200a is, for example, the same as the angle θ, where |θ|<22.5°, more specifically, 0°<|θ|<22.5°.

[0456] The fourth installation plane of optical member 1600t corresponds to lower surface 130B (plane on the negative side of the z-axis) of the rectangular parallelepiped shape of laser crystal 1130. Lower surface 130B, which is the fourth installation plane, is placed in placement region 251 of upper surface 251T of fixed base 1250. The fourth installation plane according to this embodiment is upper surface 251T of fixed base 1250.

[0457] Then, before the first arrangement step of arranging the optical member 1600t, similar to the sixth embodiment, an arrangement step of arranging the optical member 1600q, an alignment step of adjusting the position of the optical member 1600q, and a fixing step of fixing the optical member 1600q are performed. These three steps are performed before the first arrangement step of arranging the optical member 1600t. In the first alignment step, the position of the optical member 1600t is adjusted. Then, in the second alignment step, the position of the output mirror 160 is adjusted.

[0458] In the first modification of the first embodiment, the first cylindrical lens 110 bonded to the end mirror 1140 has been described. Also, in the first modification of the first embodiment, it has been described that laser oscillation can be efficiently generated by adjusting the position of the optical member 1600a. In the present embodiment, the position of the optical member 1600t is similarly adjusted. This increases the overlap between the excitation region M1 and the resonator mode region M2, allowing laser oscillation to be efficiently generated in the laser crystal 1130.

[0459] Furthermore, in this embodiment, as in the sixth embodiment, the position of optical member 1600q is adjusted, i.e., the first laser beam L1001 is adjusted so as to be amplified within optical system 290b, which is a resonator optical system. Furthermore, as in the third modification of the first embodiment, the position of optical member 1600t and output mirror 160 is adjusted, i.e., the second laser beam L1002 is adjusted so as to be amplified within optical system 290, which is a resonator optical system. This facilitates realization of light source module 1010t, which is a module combining an external-resonator laser module with a solid-state laser, and allows the wavelength of first laser beam L1001 (output beam L1100B) transmitted through diffractive optical element 180 to be a specific wavelength. For example, since the wavelength of first laser beam L1001 (output beam L1100B) transmitted through diffractive optical element 180 can be matched to the absorption peak wavelength of laser crystal 1130, laser crystal 1130 can efficiently emit second laser beam L1002. In other words, output beam L1100 can be efficiently emitted.

[0460] (Other embodiments) While the light source module 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. As long as the modifications 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 are also included within the scope of the present disclosure.

[0461] In the above-described embodiments, the first embodiment provides the following example for joining the first installation plane and the first installation surface. Specifically, this example refers to a case in which heat is applied to a joining material (e.g., a solder material) provided between the upper surface 251T (the first installation surface) and the lower surface 130B (the first installation surface) to melt the joining material. However, this is not limited to this example. The optical member may be fixed to the first installation surface by joining the side surface connected to the first installation plane with a joining material. Alternatively, the first installation plane and the first installation surface may be fixed by direct bonding without using a joining material, such as optical contact. The above applies not only to an example for joining the first installation plane and the first installation surface, but also to an example for joining the second installation plane and the second installation surface.

[0462] 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. [Industrial Applicability]

[0463] According to the present disclosure, it is possible to provide a light source module that can be adjusted in position with high precision. [Explanation of symbols]

[0464] 105 Second cylindrical lens 106 Third cylindrical lens 110 First cylindrical lens 130B, 130Bf, 160B, 180B, 1125ba, 1125bb, 1125g, 1125h, 1125ha, 1125j, 1125m, 1125s bottom 130T, 130Tb, 251T, 301T, 301Tj, 301Ts top surface 131 Placement area 160 Output mirror 161, 161d reflective film 170 Nonlinear Optical Crystals 180 Diffractive Optical Elements 180a grid direction 200 Semiconductor laser element 200a active layer 200p p electrode 200n n electrode 200r optical waveguide 201 Luminous Area 230 Submount 241, 251, 261, 271, 281 placement area 501 cases 502 Bottom plate 503 Frame 522 Lead pin 1010, 1010a, 1010b, 1010ba, 1010bb, 1010c, 1010d, 1010f, 1010j, 1010k, 1010m, 1010n, 1010p, 1010q, 1010r, 1010s, 1010t Light Source Module 1020 module package 1120, 1120b, 1120bb, 1120f, 1120g, 1120h, 1120ha, 1120j, 1120m, 1120s support members 1121b, 1121bb, 1121ha, 1121m First supporting member 1121h First auxiliary component 1122b, 1122bb, 1122ha, 1122m Second supporting member 1122h Second auxiliary member 1130, 1130bb, 1130f laser crystals 1131, 1131f, 1131bb, 181 entrance plane 1140, 200b end mirror 1240 Pedestal 1250 Fixed base 1300, 1300j, 1300s fixing parts 1500 airtight packages 1504 Lid 1505 Translucent window unit d1 Output direction L1001 First laser beam L1002 Second laser beam L1003 Third laser beam L1100, L1100B, L1100C output light LA1 1st light LA2 2nd optical axis M1 Energize the field M2 Resonator Mode Field 1600, 1600a, 1600b, 1600ba, 1600f, 1600g, 1600h, 1600ha, 1600hb, 1600j, 1600m, 1600q, 1600s, 1600t optical components 290, 290b Department of Optics

Claims

1. a semiconductor laser element that emits a first laser beam; an optical member having a first cylindrical lens and a first installation plane; Equipped with the semiconductor laser element has an active layer, The first cylindrical lens is the first laser light is incident, changing a divergence angle of the first laser beam in a fast axis direction; the first laser light emitted from the first cylindrical lens is incident on an incident surface of an optical element, The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens; a generatrix of the first cylindrical lens is inclined with respect to the first installation plane, The angle θ between the busbar and the active layer is |θ| < 22.5° is Light source module.

2. a semiconductor laser element that emits a first laser beam; an optical member having a first cylindrical lens and a first installation plane; Equipped with the semiconductor laser element has an active layer, The first cylindrical lens is the first laser light is incident, changing a divergence angle of the first laser beam in a fast axis direction; the first laser light emitted from the first cylindrical lens is incident on an incident surface of an optical element, The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens; a generatrix of the first cylindrical lens is inclined with respect to the first installation plane; The angle θ between the busbar and the active layer is |θ| < 22.5° is Light source module.

3. The busbar is inclined with respect to the first installation plane. The light source module according to claim 2 .

4. The first cylindrical lens is fixed to the optical element. The light source module according to any one of claims 1 to 3.

5. a fixing member having the first flat installation surface, the optical member includes the optical element having the first installation plane, The first cylindrical lens is fixed to the first installation plane via the optical element. The light source module according to claim 4 .

6. The optical element has the first installation plane, The first installation plane is fixed to the first installation plane, whereby the optical member is installed on the optical element. The light source module according to claim 4 .

7. a fixing member having the first flat installation surface, The first installation plane is fixed to the first installation surface, and the optical member is installed on the fixing member. The light source module according to any one of claims 1 to 3.

8. the first laser light has a first emission peak wavelength, The optical element converts the first laser light incident on the optical element into a second laser light having a second emission peak wavelength different from the first emission peak wavelength. The light source module according to any one of claims 1 to 7.

9. The second emission peak wavelength is longer than the first emission peak wavelength. The light source module according to claim 8 .

10. a first optical filter provided on the incident surface for reflecting the second laser light; 10. The light source module according to claim 8 or 9.

11. Equipped with an optical system having a predetermined optical axis The light source module according to claim 10.

12. The optical system is a resonator optical system. The light source module according to claim 11 .

13. The first optical filter is part of the optical system. The light source module according to claim 11 or 12.

14. a second optical filter that reflects the second laser light; The light source module according to any one of claims 11 to 13.

15. the second optical filter has a second mounting plane; The second installation plane is fixed to a plane parallel to the first installation plane. The light source module according to claim 14.

16. The second optical filter has a concave surface and a reflective film provided on the concave surface.

16. The light source module according to claim 14 or 15.

17. a nonlinear optical crystal disposed between the optical element and the second optical filter; The light source module according to any one of claims 14 to 16.

18. a second cylindrical lens disposed between the first cylindrical lens and the semiconductor laser element; The light source module according to any one of claims 1 to 17.

19. The semiconductor laser element and the optical element are hermetically sealed in an airtight package. The light source module according to any one of claims 1 to 18.

20. Furthermore, it is equipped with a nonlinear optical crystal, The nonlinear optical crystal is hermetically sealed in the hermetic package.

20. The light source module of claim 19.

21. The optical element is a diffractive optical element. The light source module according to any one of claims 1 to 7.

22. The diffractive optical element is a volume holographic diffraction grating.

22. The light source module of claim 21.

23. A method for manufacturing a light source module, comprising: The light source module includes: a semiconductor laser element that emits a first laser beam; an optical member having a first cylindrical lens, an optical element, and a first installation plane; Equipped with the semiconductor laser element has an active layer, The first cylindrical lens is the first laser light is incident, changing a divergence angle of the first laser beam in a fast axis direction; the first laser light emitted from the first cylindrical lens is incident on an incident surface of the optical element, The first installation plane is fixed to a first installation plane, thereby fixing the first cylindrical lens; The manufacturing method includes: a first placement step of placing the optical member on the first installation plane so that a generatrix of the first cylindrical lens is inclined with respect to the first installation plane; a first alignment step of causing the first laser light emitted from the semiconductor laser element to be incident on the first cylindrical lens and moving the arranged optical member in two directions parallel to the first installation plane and perpendicular to each other; a first fixing step of fixing the first installation plane of the moved optical member to the first installation plane, In the first arranging step, the angle θ between the busbar and the active layer is |θ| < 22.5° is Manufacturing method.

24. the first cylindrical lens is fixed to the optical element; the first laser light has a first emission peak wavelength, the optical element converts the first laser light incident on the optical element into a second laser light having a second emission peak wavelength different from the first emission peak wavelength, the light source module includes an optical system having a predetermined optical axis and including a first optical filter and a second optical filter; the first optical filter is provided on the incident surface and reflects the second laser light; the second optical filter reflects the second laser light; The manufacturing method includes: a second placement step of placing the second optical filter on a second installation surface; a second alignment step of moving the second optical filter in the two directions; and a second fixing step of fixing the moved second optical filter to the second installation surface. The method of claim 23.

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