Laser Light Source

Abstract

To provide a laser beam source in which a positional deviation between a laser diode chip and a lens is hardly generated.SOLUTION: A laser beam source comprises: a semiconductor lamination structure containing a light emission layer; a laser diode chip that includes a first end surface emitting a laser beam generated in the light emission layer and a second end surface on the opposite side thereof, and in which a length of an oscillator is regulated by a distance of both end surfaces; a sub-mount that has a main flat surface to which the chip is fixed, and a back surface on the opposite side thereof; a pair of lens support parts that is arranged onto the main flat surface, and is positioned to both sides of the first end surface; a coupling part that couples the pair of lens support parts, and is overlapped with the first end surface in a top surface view; a lens that is connected to the end surface of the pair of lens support parts; and a semiconductor laser package that houses those construction elements. The first end surface is projected to a direction of the length of the oscillator from an edge of the main flat surface. The end surface of the pair of lens support parts is projected to the direction of the length of the oscillator from the first end surface, and the pair of lens support parts and the coupling part are integrally formed.SELECTED DRAWING: Figure 8A

Description

[Technical field]

[0001] The present disclosure relates to laser light sources. [Background technology]

[0002] Laser light sources are used for various purposes such as processing, projectors, and lighting equipment. A typical example of such a laser light source includes a laser diode chip, a submount that supports the laser diode chip, and a collimating lens that reduces the divergence angle of the laser light emitted from the laser diode chip (for example, Patent Document 1). When the laser diode chip, the submount, and a lens such as a collimating lens are housed in a semiconductor laser package, it becomes possible to collimate the laser light by a small lens before the laser light diverges significantly. On the other hand, a slight misalignment between the laser diode chip and the lens may cause a large misalignment of the optical axis of the laser light emitted to the outside from the laser light source. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2000-98190 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for a laser light source in which misalignment between the laser diode chip and the lens is unlikely to occur. [Means for solving the problem]

[0005] In one embodiment, a laser light source according to the present disclosure includes: a semiconductor laminated structure including a light emitting layer; a substrate supporting the semiconductor laminated structure; an edge-emitting laser diode chip having a first end face for emitting laser light generated in the light emitting layer and a second end face opposite to the first end face, wherein a cavity length is defined by the distance from the first end face to the second end face; a submount having a main plane to which the laser diode chip is fixed, a pair of lens support parts located on both sides of the first end face of the laser diode chip, and a back surface located on the opposite side to the main plane; the laser diode chip is fixed to the submount with the light emitting layer closer to the submount than the substrate of the laser diode chip, the first end face of the laser diode chip protrudes in the direction of the cavity length beyond an edge of the main plane, and the end faces of the pair of lens support parts protrude in the direction of the cavity length beyond the first end face of the laser diode chip. Effect of the Invention

[0006] According to the present disclosure, it is possible to realize a laser light source in which misalignment between the laser diode chip and the lens is unlikely to occur. [Brief description of the drawings]

[0007] [Figure 1A] FIG. 1A is a perspective view that illustrates a schematic configuration example of a laser light source 100 according to the first embodiment of the present disclosure. [Figure 1B] FIG. 1B is a diagram that illustrates a planar configuration of the laser light source 100 in FIG. 1A. [Figure 2A] FIG. 2A is a perspective view showing in more detail the configuration of the laser light source 100 in FIG. 1A with the semiconductor laser package 40 and the pair of lead terminals 50 omitted. [Figure 2B] FIG. 2B is a top view that diagrammatically illustrates the laser light source 100 of FIG. 2A. [Figure 2C] FIG. 2C is a cross-sectional view of the configuration of FIG. 2B taken along line IIC-IIC parallel to the YZ plane. [Figure 3A] FIG. 3A is a perspective view that illustrates a schematic configuration example of a laser light source 110 in a first modification of the first embodiment of the present disclosure. [Figure 3B] FIG. 3B is a top view that diagrammatically illustrates the laser light source 110 of FIG. 3A. [Figure 3C] FIG. 3C is a cross-sectional view of the configuration of FIG. 3B taken along line IIIC-IIIC parallel to the YZ plane. [Figure 4A] FIG. 4A is a perspective view that illustrates a schematic configuration example of the laser light source 120 in Modification 2 of Embodiment 1 of the present disclosure. [Figure 4B] FIG. 4B is a top view that diagrammatically illustrates the laser light source 120 of FIG. 4A. [Figure 4C] FIG. 4C is a cross-sectional view of the configuration of FIG. 4B taken along line IVC-IVC parallel to the YZ plane. [Figure 5A] FIG. 5A is a perspective view that illustrates a schematic configuration example of a laser light source 130 according to a third modification of the first embodiment of the present disclosure. [Figure 5B] FIG. 5B is a top view that diagrammatically illustrates the laser light source 130 of FIG. 5A. [Figure 5C] FIG. 5C is a cross-sectional view of the configuration of FIG. 5B taken along line VC-VC parallel to the YZ plane. [Figure 6A] FIG. 6A is a perspective view that illustrates a schematic configuration example of the laser light source 140 in the fourth modification of the first embodiment of the present disclosure. [Figure 6B] FIG. 6B is a top view that diagrammatically illustrates the laser light source 140 of FIG. 6A. [Figure 6C] FIG. 6C is a cross-sectional view of the configuration of FIG. 6B taken along line VIC-VIC parallel to the YZ plane. [Figure 7A] FIG. 7A is a perspective view that illustrates a schematic configuration example of a laser light source 150 according to a fifth modification of the first embodiment of the present disclosure. [Figure 7B] FIG. 7B is a top view that diagrammatically illustrates the laser light source 150 of FIG. 7A. [Figure 7C]FIG. 7C is a cross-sectional view of the configuration of FIG. 7B taken along line VIIC-VIIC parallel to the YZ plane. [Figure 7D] FIG. 7D is a perspective view that illustrates a state in which the collimator lens 30 in the laser light source 150 in FIG. 7A is bonded to the submount 20 using a collet 60. As shown in FIG. [Figure 8A] FIG. 8A is a perspective view that illustrates a schematic configuration example of a laser light source 200 according to the second embodiment of the present disclosure. [Figure 8B] FIG. 8B is a top view that diagrammatically illustrates the laser light source 200 of FIG. 8A. [Figure 8C] FIG. 8C is a cross-sectional view of the configuration of FIG. 8B taken along line VIIIC-VIIIC parallel to the YZ plane. [Figure 8D] FIG. 8D is a rear view that diagrammatically illustrates the laser light source 200 of FIG. 8A. [Figure 9A] FIG. 9A is a perspective view that illustrates a schematic configuration example of a laser light source 210 in Modification 1 of Embodiment 2 of the present disclosure. [Figure 9B] FIG. 9B is a top view that diagrammatically illustrates the laser light source 210 of FIG. 9A. [Figure 9C] FIG. 9C is a cross-sectional view of the configuration of FIG. 9B taken along line IXC-IXC parallel to the YZ plane. [Figure 9D] FIG. 9D is a rear view that diagrammatically illustrates the laser light source 210 of FIG. 9A. [Figure 10A] FIG. 10A is a perspective view that illustrates a schematic configuration example of a laser light source 220 in Modification 2 of Embodiment 2 of the present disclosure. [Figure 10B] FIG. 10B is a top view that diagrammatically illustrates the laser light source 220 of FIG. 10A. [Figure 10C] FIG. 10C is a cross-sectional view of the configuration of FIG. 10B taken along line XC-XC parallel to the YZ plane. [Figure 10D] FIG. 10D is a perspective view that diagrammatically illustrates the fourth submount part 20p4 and the collimating lens 30 in FIG. 10A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, a laser light source according to an embodiment of the present disclosure will be described in detail with reference to the drawings. Parts having the same reference numerals appearing in multiple drawings indicate the same or equivalent parts.

[0009] Furthermore, the following are examples to embody the technical ideas of the present disclosure, and the present disclosure is not limited to the following. Furthermore, the description of the dimensions, materials, shapes, relative positions, etc. of the components is intended to be illustrative, and not to limit the scope of the present disclosure. The sizes and positional relationships of the components shown in each drawing may be exaggerated to make it easier to understand.

[0010] (Embodiment 1) First, a basic configuration example of a laser light source according to a first embodiment of the present disclosure will be described with reference to FIGS. 1A and 1B and FIGS. 2A to 2C.

[0011] FIG. 1A is a perspective view showing a schematic configuration example of a laser light source 100 in the first embodiment of the present disclosure. FIG. 1B is a diagram showing a schematic planar configuration of the laser light source 100 in FIG. 1A. The laser light source 100 in this embodiment includes a laser diode chip 10, a submount 20 supporting the laser diode chip 10, a collimating lens 30 supported by the submount 20, and a semiconductor laser package 40 housing these elements or components. The laser light source 100 in this embodiment also includes a pair of lead terminals 50 penetrating the semiconductor laser package 40 and supplying power to the laser diode chip 10. The semiconductor laser package 40 includes a lid 40L, a base 40b, and a light-transmitting window 40w. In the laser light source 100 in this embodiment, the laser light emitted from the laser diode chip 10 and collimated by the collimating lens 30 is taken out from the light-transmitting window 40w.

[0012] In Fig. 1A, for ease of understanding, the lid 40L, the base 40b, and the light-transmitting window 40w in the semiconductor laser package 40 are shown in a separated state, but in reality, they are joined together. In Fig. 1B, the lid 40L in the semiconductor laser package 40 is omitted.

[0013] In the drawings, for reference, mutually orthogonal X-axis, Y-axis, and Z-axis are shown diagrammatically. For ease of explanation, in this disclosure, the side on which the laser diode chip 10, the submount 20, and the collimating lens 30 are located in the base body 40b may be expressed as "upper". This does not limit the orientation of the laser light source 100 when in use, and the orientation of the laser light source 100 is arbitrary.

[0014] FIG. 2A is a perspective view showing the details of the configuration of the laser light source 100 of FIG. 1A with the semiconductor laser package 40 and the pair of lead terminals 50 omitted. In FIG. 2A, the area surrounded by the dashed line shows an example of the detailed structure of the laser diode chip 10 arranged on the submount 20. In FIG. 2A, the submount 20 and the collimating lens 30 are shown in a separated state, but in reality, they are joined together. FIG. 2B is a top view showing the laser light source 100 of FIG. 2A. FIG. 2C is a cross-sectional view of the configuration of FIG. 2B taken along line IIC-IIC parallel to the YZ plane. In the present disclosure, the side on which the collimating lens 30 is located with respect to the submount 20 may be expressed as "front".

[0015] As shown in FIG. 2A, the laser diode chip 10 is an edge-emitting type laser diode chip, and has a semiconductor laminated structure 10a including a first cladding layer 10C1, a second cladding layer 10C2, and a light-emitting layer 10L, a substrate 10b supporting the semiconductor laminated structure 10a, an emission end face 10e1 that emits high-power laser light generated in the light-emitting layer 10L, and a rear end face 10e2 opposite to the emission end face 10e1. The light-emitting layer 10L is located between the first cladding layer 10C1 and the second cladding layer 10C2. The laser diode chip 10 may include other layers such as a buffer layer and a contact layer. In this disclosure, the "emission end face 10e1" may be referred to as the "first end face 10e1", and the "rear end face 10e2" may be referred to as the "second end face 10e2".

[0016] The laser diode chip 10 is fixed to the submount 20 in a face-down state in which the light emitting layer 10L is closer to the submount 20 than the substrate 10b. The total size in the Y direction of the semiconductor laminated structure 10a and the substrate 10b in the laser diode chip 10 is about 80 μm. The total size in the Y direction of the substrate 10b and the first cladding layer 10C1 is larger than the size in the Y direction of the second cladding layer 10C2. In the face-down state, the distance between the light emitting layer 10L and the submount 20 is about one tenth of that in the face-up state in which the light emitting layer 10L is farther from the submount 20 than the substrate 10b. Therefore, in the face-down state, even if a high-power laser light is emitted from the light emitting layer 10L, the heat generated in the light emitting layer 10L can be efficiently transferred to the submount 20. The output of the laser light in this embodiment is, for example, 3 W or more and 50 W or less.

[0017] The semiconductor laminated structure 10a may have, for example, a double heterostructure that forms an energy level of a quantum well. The band gap of the light emitting layer 10L is smaller than the band gaps of the first cladding layer 10C1 and the second cladding layer 10C2. In this embodiment, the substrate 10b and the first cladding layer 10C1 on the substrate 10b may each be formed from an n-type semiconductor. The light emitting layer 10L may be formed from an intrinsic semiconductor, an n-type semiconductor, or a p-type semiconductor, and the second cladding layer 10C2 on the light emitting layer 10L may be formed from a p-type semiconductor. The n-type and p-type may be reversed. Current injection from the p-type cladding layer to the n-type cladding layer causes carrier population inversion in the light emitting layer 10L, and stimulated emission of light from the light emitting layer 10L occurs. The refractive index of the light emitting layer 10L is designed to be higher than the refractive index of the first cladding layer 10C1 and the second cladding layer 10C2, and the light generated in the light emitting layer 10L is confined in the light emitting layer 10L by total reflection. The light emitting layer 10L functions as a resonator, and laser light is emitted from the emission end face 10e1 of the light emitting layer 10L. The resonator length of the light emitting layer 10L is determined by the distance from the emission end face 10e1 to the rear end face 10e2. The direction of the resonator length is parallel to the Z direction. The resonator length is, for example, 500 μm or more and 5000 μm or less. When the resonator length is long, the contact area between the laser diode chip 10 and the submount 20 can be widened, so that the heat generated in the light emitting layer 10L can be efficiently transferred to the submount 20.

[0018] The laser light emitted from the emission end surface 10e1 of the laser diode chip 10 diverges quickly in the YZ plane and diverges slowly in the XZ plane as it propagates. When not collimated, the spot of the laser light has an elliptical shape in the far field with the Y direction as the major axis and the X direction as the minor axis in the XY plane.

[0019] The laser diode chip 10 can emit violet, blue, green or red laser light in the visible region, or infrared or ultraviolet laser light. The emission peak wavelength of the violet light is preferably in the range of 350 nm to 419 nm, more preferably in the range of 400 nm to 415 nm. The emission peak wavelength of the blue light is preferably in the range of 420 nm to 494 nm, more preferably in the range of 440 nm to 475 nm. The semiconductor laser element that emits the violet or blue laser light includes a semiconductor laser element that includes a nitride semiconductor. As the nitride semiconductor, for example, GaN, InGaN, and AlGaN can be used. The emission peak wavelength of the green light is preferably in the range of 495 nm to 570 nm, more preferably in the range of 510 nm to 550 nm. As the semiconductor laser element that emits the green laser light, a semiconductor laser element that includes a nitride semiconductor can be used. As the nitride semiconductor, for example, GaN, InGaN, and AlGaN can be used. The emission peak wavelength of the red light is preferably in the range of 605 nm to 750 nm, more preferably in the range of 610 nm to 700 nm. Examples of the semiconductor laser element that emits red laser light include semiconductor laser elements including InAlGaP, GaInP, GaAs, and AlGaAs semiconductors. A semiconductor laser element having two or more waveguide regions can be used as the red semiconductor laser element. The output of the semiconductor laser element including these semiconductors is more likely to decrease due to heat than that of a semiconductor laser element including a nitride semiconductor. By increasing the waveguide region, the heat can be dispersed, thereby reducing the decrease in the output of the semiconductor laser element.

[0020] The submount 20 has a main plane 20s1 to which the laser diode chip 10 is fixed, a pair of lens support parts 20LS located on both sides of the emission end face 10e1 of the laser diode chip 10, a back surface 20s2 located on the opposite side of the main plane 20s1, and a front end face 20fe connecting the main plane 20s1 and the back surface 20s2. The main plane 20s1 and the front end face 20fe define an edge 20ed of the main plane 20s1. In the example shown in FIG. 2A, the pair of lens support parts 20LS are a pair of convex parts located on both sides of the laser diode chip 10 and extending in the Z direction. The submount 20 has the following U-shaped shape extending in the Z direction behind the front end face 20fe. This U-shaped shape is formed by dividing a square cylinder that is mirror symmetric with respect to a plane parallel to the YZ plane and extends in the Z direction by a plane parallel to the XZ plane. The end faces 20se of the pair of lens support parts 20LS protrude in the cavity length direction beyond the emission end face 10e1 of the laser diode chip 10. The normal direction of the main plane 20s1 is parallel to the Y direction.

[0021] The distance in the Z direction between the end faces 20se of the pair of lens support parts 20LS and the emission end face 10e1 of the laser diode chip 10 can be designed to be approximately equal to the focal length of the collimator lens 30. The distance in the Z direction between the end faces 20se of the pair of lens support parts 20LS and the emission end face 10e1 of the laser diode chip 10 is, for example, 50 μm or more and 100 μm or less. The size in the Y direction of the pair of lens support parts 20LS can be approximately the same as the size in the Y direction of the collimator lens 30. The size in the Y direction of the pair of lens support parts 20LS may be larger than, equal to, or smaller than the size in the Y direction of the collimator lens 30. The size in the Y direction of the pair of lens support parts 20LS is, for example, 100 μm or more and 500 μm or less.

[0022] The size of the submount 20 in the X direction is, for example, 1 mm or more and 3 mm or less, the size of the portion of the submount 20 other than the pair of lens support portions 20LS in the Y direction is, for example, 100 μm or more and 500 μm or less, and the size of the portion of the submount 20 other than the pair of lens support portions 20LS in the Z direction is, for example, 1 mm or more and 6 mm or less. In the present disclosure, the upper limit of the size may be determined from the viewpoint of miniaturization of the laser light source 100.

[0023] In the submount 20, the emission end surface 10e1 of the laser diode chip 10 protrudes in the cavity length direction beyond the edge 20ed of the main plane 20s1. The distance in the Z direction between the emission end surface 10e1 of the laser diode chip 10 and the edge 20ed of the main plane 20s1 is, for example, 2 μm or more and 50 μm or less. With this arrangement, even if the laser diode chip 10 and the main plane 20s1 of the submount 20 are fixed with an inorganic bonding material such as gold-tin in a face-down state, the bonding material can be prevented from rising up to the emission end surface 10e1 of the light-emitting layer 10L. In the laser light source disclosed in Patent Document 1, when the laser diode chip is placed in a face-down state, the bonding material bonding the laser diode chip and the submount may rise up to the emission end surface of the light-emitting layer in the laser diode chip. As a result, the output of the laser light emitted from the laser diode chip may decrease. In the laser light source 100 in this embodiment, such a decrease in the output of the laser light can be suppressed.

[0024] A part or the whole of the submount 20 may be formed from, for example, a ceramic containing at least one selected from the group consisting of AlN, SiC, and alumina, and an alloy such as CuW. The submount 20 may be fabricated, for example, by sintering ceramic powder. The thermal conductivity of the ceramic may be, for example, 10 [W / m·K] or more and 500 [W / m·K] or less. Furthermore, the ceramic may have a low thermal expansion coefficient in order to suppress deformation due to heat applied when the laser diode chip 10 is fixed. The thermal expansion coefficient is 2×10 -6 [1 / K] or more 1×10 -5[1 / K] or less. A metal film such as gold plating having a thickness of, for example, 0.5 μm to 10 μm may be formed on the main plane 20s1 and the back surface 20s2 of the submount 20. The metal film formed on the main plane 20s1 allows the laser diode chip 10 to be bonded to the main plane 20s1 with, for example, gold-tin. The metal film formed on the back surface 20s2 allows the submount 20 to be bonded to the bottom 40b1 with, for example, gold-tin.

[0025] The collimating lens 30 is a so-called FAC (Fast Axis Collimator) lens that collimates the components of the laser light emitted from the laser diode chip 10 that diverge greatly in the YZ plane. A so-called SAC (Slow Axis Collimator) lens (not shown) that collimates the components of the laser light that diverge little in the XZ plane may be disposed outside the laser light source 100 as necessary. In this disclosure, "collimating" includes not only making the laser light parallel, but also reducing the divergence angle of the laser light. Note that, depending on the application, other lenses such as a condenser lens may be used instead of the collimating lens 30.

[0026] The collimator lens 30 is a cylindrical lens having a structure extending in the X direction, has no curvature in the X-axis direction, and has a curvature in the Y direction. The direction in which the collimator lens 30 extends is perpendicular to both the normal direction of the main plane 20s1 of the submount 20 and the cavity length direction. Since the sizes of the collimator lens 30 and the pair of lens support parts 20LS in the Y direction are approximately the same, it is easy to provide the collimator lens 30 so that its center of gravity is located between the pair of lens support parts 20LS when viewed from the cavity length direction. This arrangement of the center of gravity of the collimator lens 30 allows the collimator lens 30 to be provided on the submount 20 stably and accurately.

[0027] In this embodiment, when the rear surface 20s2 of the submount 20 is used as a reference, the height of the upper surface of the pair of lens support parts 20LS in the Y direction is approximately equal to the height of the upper surface of the collimator lens 30 in the Y direction. The position of the collimator lens 30 relative to the pair of lens support parts 20LS is roughly adjusted so that the above two heights are approximately equal. Thereafter, while emitting laser light from the laser diode chip 10, the position of the collimator lens 30 relative to the pair of lens support parts 20LS is finely adjusted so that the laser light is appropriately collimated. Note that the above two heights do not necessarily need to be approximately equal and may be different.

[0028] Since the collimating lens 30 in this embodiment is uniform along the X direction, there is no need to consider the alignment of the emission end surface 10e1 of the laser diode chip 10 and the collimating lens 30 in the X direction. Of the collimating lens 30, only the facing portion facing the emission end surface 10e1 of the laser diode chip 10 and its peripheral portion need to be uniform along the X direction. Therefore, the other two side portions do not necessarily need to be uniform along the X direction, and do not necessarily need to be transparent. The size of the two side portions of the collimating lens 30 in the Y direction may be larger, equal, or smaller than the size of the facing portion and its peripheral portion in the Y direction. The collimating lens 30 may be formed of at least one of, for example, glass, quartz, synthetic quartz, sapphire, transparent ceramic, and plastic.

[0029] The collimating lens 30 is bonded to the end faces 20se of the pair of lens support parts 20LS in the Z direction. Even if there is some variation in the thickness of the bonding material bonding the collimating lens 30 to the end faces 20se of the pair of lens support parts 20LS, the variation has almost no effect on the position of the collimating lens 30 in the Y direction. Unlike the configuration of this embodiment, it is also possible to place a pedestal having a flat surface parallel to the main flat surface 20s1 in front of the submount 20 and provide the collimating lens 30 on the flat surface of the pedestal. However, in such a configuration, if there is variation in the thickness of the bonding material between the collimating lens 30 and the flat surface of the pedestal, a positional deviation in the Y direction between the laser diode chip 10 and the collimating lens 30 occurs, and the direction of the optical axis of the laser light emitted to the outside from the laser light source 100 may be significantly shifted. In contrast, in this embodiment, positional deviation in the Y direction between the laser diode chip 10 and the collimator lens 30 is less likely to occur, and the optical axis of the laser light emitted to the outside from the laser light source 100 can be directed in the direction as designed. Even if some variation occurs in the thickness of the bonding material, the position of the collimator lens 30 only changes slightly along the optical axis of the laser light, and the variation has almost no effect on the direction of the optical axis of the laser light.

[0030] The collimating lens 30 and the end faces 20se of the pair of lens support parts 20LS may be bonded with an inorganic bonding material such as gold-tin. Metal films may be formed in advance on the bonding surfaces of the collimating lens 30 and the end faces 20se of the pair of lens support parts 20LS. These metal films enable bonding with, for example, gold-tin. The bonding temperature of gold-tin is about 280°C. If the thermal conductivity of the ceramic forming the submount 20 is low, the influence of heat on the laser diode chip 10 during bonding between the collimating lens 30 and the end faces 20se of the pair of lens support parts 20LS can be reduced.

[0031] As another example, the collimator lens 30 and the end faces 20se of the pair of lens support parts 20LS may be bonded with a bonding material containing a thermosetting resin. The bonding temperature of the thermosetting resin is about 100° C., which is lower than the bonding temperature of inorganic materials. Therefore, the influence of heat on the laser diode chip 10 during bonding between the collimator lens 30 and the end faces 20se of the pair of lens support parts 20LS can be further reduced. In bonding between the collimator lens 30 and the end faces 20se of the pair of lens support parts 20LS, the thermosetting resin may be heated, for example, by irradiating the position of point P shown in FIG. 2A with laser light. The distance in the Z direction between the position of point P and the end faces 20se of the pair of lens support parts 20LS is, for example, 50 μm or more and 500 μm or less. In this embodiment, the optical axis of the laser light emitted from the laser diode chip 10 does not overlap with the bonding material when viewed from above, so that even if outgassing occurs from the bonding material containing a thermosetting resin, the outgassing can be suppressed from approaching the laser diode chip 10. As a result, dust collection on the emission end surface 10e1 of the laser diode chip 10 can be suppressed, as will be described later.

[0032] Some inorganic bonding materials may contain organic matter as a binder. Even if such bonding materials are used to bond the collimator lens 30 to the end faces 20se of the pair of lens support parts 20LS, outgassing generated by heating can be prevented from approaching the laser diode chip 10.

[0033] The collimating lens 30 and the end faces 20se of the pair of lens support parts 20LS may be bonded to each other by direct bonding without using a bonding material. Examples of direct bonding include diffusion bonding, room temperature bonding, and anodic bonding.

[0034] As is clear from the description of the embodiment in which a bonding material is used, the direct bonding can also suppress positional deviation of the collimator lens 30 in the Y direction, similar to the bonding using a bonding material.

[0035] In the laser light source 100 of this embodiment, the submount 20 supports the laser diode chip 10 and the collimator lens 30. Since the distance between the emission end face 10e1 of the laser diode chip 10 and the collimator lens 30 is short, the small collimator lens 30 can reduce the divergence of the laser light emitted from the laser diode chip 10 before it diverges significantly. Therefore, it is possible to realize a small-sized laser light source 100. In addition, it is possible to reduce the diameter of the collimated beam that has passed through the collimator lens 30.

[0036] The semiconductor laser package 40 may hermetically seal the laser diode chip 10, the submount 20, and the collimating lens 30. When the laser diode chip 10 emits a short wavelength laser light, for example, 350 nm or more and 570 nm or less, organic gas components contained in the atmosphere may be decomposed by the laser light, and the decomposed products may adhere to the emission end face 10e1 of the laser diode chip 10. In addition, if the emission end face 10e1 of the laser diode chip 10 is in contact with the outside air, the end face may deteriorate during operation due to dust collection, etc. Such end face deterioration may lead to a decrease in the optical output of the laser diode chip 10. In order to increase the reliability of the laser diode chip 10 and extend its life, it is desirable that the semiconductor laser package 40 hermetically seals the laser diode chip 10. The hermetic sealing by the semiconductor laser package 40 may be performed regardless of whether the wavelength of the laser light emitted from the laser diode chip 10 is long or short.

[0037] The base 40b in the semiconductor laser package 40 is in thermal contact with the back surface 20s2 of the submount 20. The base 40b may be made of a material with high thermal conductivity. The material may be, for example, a metal containing at least one selected from the group consisting of Cu, Al, Ag, Fe, Ni, Mo, Cu, W, and CuMo. In order to match the height of the emission end surface 10e1 of the laser diode chip 10 and the light-transmitting window 40w, a member 40m with high thermal conductivity may be provided between the bottom surface 40bt of the base 40b and the submount 20, as shown in FIG. 1B. The member 40m may be made of the same material as the portion including the bottom surface 40bt of the base 40b. Alternatively, at least a part of the bottom surface 40bt of the base 40b may be raised, and the submount 20 may be disposed on the raised bottom surface 40bt. The portion including the bottom surface 40bt of the base 40b may be made of, for example, copper. The portion of the base 40b surrounding the laser diode 10, the submount 20, and the collimating lens 30 may be made of, for example, kovar. Kovar is an alloy of nickel and cobalt added to iron, which is the main component. The cover 40L of the semiconductor laser package 40 may be made of the same material as the base 40b, or may be made of a different material. The light-transmitting window 40w of the semiconductor laser package 40 is attached to the base 40b and transmits the laser light emitted from the laser diode chip 10. The light-transmitting window 40w of the semiconductor laser package 40 may be made of at least one of glass, quartz, synthetic quartz, sapphire, transparent ceramic, and plastic, similar to the collimating lens 30.

[0038] The pair of lead terminals 50 are electrically connected to the laser diode chip 10 by wires as follows. In the example shown in FIG. 2A, a metal film such as gold plating is formed on the upper surface of the laser diode chip 10. The metal film and one of the pair of lead terminals 50 are electrically connected by wires. Similarly, a metal film such as gold plating is also formed on the main plane 20s1 of the submount 20. The metal film and the other of the pair of lead terminals 50 are electrically connected by wires. A current is injected from the second cladding layer 10C2 to the first cladding layer 10C1 of the laser diode chip 10 by the pair of lead terminals 50. The pair of lead terminals 50 are electrically connected to an external circuit (not shown) that adjusts the emission timing and output of the laser light emitted from the laser diode chip 10. The pair of lead terminals 50 are formed of a material with good conductivity. Examples of such materials include metals such as Fe-Ni alloys and Cu alloys.

[0039] In the laser light source 100 of this embodiment, the submount 20 supports the laser diode chip 10 by the main plane 20s1 between the pair of lens support parts 20LS, and supports the collimator lens 30 by the end face 20se of the pair of lens support parts 20LS. This makes it easy to align the laser diode chip 10 and the collimator lens 30 as described above, and makes it possible to realize a compact laser light source 100. Furthermore, in the laser light source 100 of this embodiment, even if the laser diode chip 10 is placed face-down on the submount 20, it is possible to prevent the bonding material from rising up to the emission end face 10e1 of the laser diode chip 10.

[0040] (Modification of the first embodiment) Next, modified examples 1 to 5 of the laser light source 100 according to the first embodiment of the present disclosure will be described. In the following modified examples, the semiconductor laser package 40 and the pair of lead terminals 50 are omitted. Descriptions that overlap with those described above may be omitted.

[0041] A configuration example of the laser light source 110 in Modification 1 of the embodiment 1 of the present disclosure will be described with reference to FIG. 3A to FIG. 3C. FIG. 3A is a perspective view that shows a schematic configuration example of the laser light source 110 in Modification 1 of the embodiment 1 of the present disclosure. FIG. 3B is a top view that shows a schematic configuration example of the laser light source 110 in FIG. 3A. FIG. 3C is a cross-sectional view of the configuration in FIG. 3B along line IIIC-IIIC parallel to the YZ plane. The laser light source 110 in Modification 1 of the embodiment 1 differs from the laser light source 100 in the embodiment 1 in the shape of the submount 20. The front end face 20fe in the submount 20 has a central end face 20fe1 and both side end faces 20fe2 located on both sides of the central end face 20fe1. The central end face 20fe1 is recessed in the cavity length direction from the both side end faces 20fe2. The edge 20ed of the main plane 20s1 in Modification 1 of the embodiment 1 is defined by the main plane 20s1 and the central end face 20fe1. The size of the recess in the central end face 20fe1 in the Z direction is, for example, 5 μm or more and 100 μm or less, the size in the X direction is, for example, 50 μm or more and 200 μm or less, and the size in the Y direction from the main flat surface 20s1 is, for example, 100 μm or more and 500 μm or less. The recess does not necessarily have to penetrate in the Y direction.

[0042] The emission end face 10e1 of the laser diode chip 10 protrudes in the cavity length direction beyond the edge 20ed of the main plane 20s1 defined by the main plane 20s1 and the central end face 20fe1. The two end faces 20fe2 of the submount 20 protrude in the cavity length direction beyond the emission end face 10e1 of the laser diode chip 10, similar to the end faces 20se of the pair of lens supports 20LS. The edge 20ed of the main plane 20s1 defined by the main plane 20s1 and the central end face 20fe1 can prevent the bonding material from rising up to the emission end face 10e1 of the laser diode chip 10. The submount 20 in the first modification of the first embodiment can be easily manufactured because it is only necessary to remove a part of the front end face 20fe in the above-mentioned U-shaped shape extending in the Z direction. In addition, since the collimating lens 30 is bonded to the L-shaped end faces including the end faces 20se and both side end faces 20fe2 of the pair of lens support parts 20LS, the contact area between the collimating lens 30 and the submount 20 is increased, making bonding easier.

[0043] Next, with reference to FIG. 4A to FIG. 4C, a configuration example of the laser light source 120 in Modification 2 of the embodiment 1 of the present disclosure will be described. FIG. 4A is a perspective view that shows a schematic configuration example of the laser light source 120 in Modification 2 of the embodiment 1 of the present disclosure. FIG. 4B is a top view that shows a schematic configuration example of the laser light source 120 in FIG. 4A. FIG. 4C is a cross-sectional view of the configuration of FIG. 4B along the IVC-IVC line parallel to the YZ plane. The laser light source 120 in Modification 2 of the embodiment 1 differs from the laser light source 100 in the embodiment 1 in the shape of the submount 20. The submount 20 in Modification 2 of the embodiment 1 has a groove 20d extending along the cavity length direction between each of the pair of lens supports 20LS and the laser diode chip 10. In the example shown in FIG. 4B, the groove 20d is adjacent to the pair of lens supports 20LS, but does not necessarily have to be adjacent. The size of the groove 20d in the X direction is, for example, 100 μm or more and 500 μm or less, the size in the Y direction is, for example, 50 μm or more and 300 μm or less, and the size in the Z direction from the edge 20ed of the main plane 20s1 is, for example, 1 mm or more and 6 mm or less. The groove 20d does not necessarily have to penetrate in the Z direction. The groove 20d can reduce the influence of heat on the laser diode chip 10 when the collimator lens 30 and the end faces 20se of the pair of lens support parts 20LS are joined.

[0044] Next, with reference to FIG. 5A to FIG. 5C, a configuration example of the laser light source 130 in the modified example 3 of the embodiment 1 of the present disclosure will be described. FIG. 5A is a perspective view that shows a schematic configuration example of the laser light source 130 in the modified example 3 of the embodiment 1 of the present disclosure. FIG. 5B is a top view that shows a schematic configuration of the laser light source 130 in FIG. 5A. FIG. 5C is a VC-VC line cross-sectional view parallel to the YZ plane of the configuration of FIG. 5B. The laser light source 130 in the modified example 3 of the embodiment 1 differs from the laser light source 100 in the embodiment 1 in the configuration of the submount 20. The submount 20 in the modified example 3 of the embodiment 1 includes a first submount portion 20p1 and a second submount portion 20p2. The first submount portion 20p1 has a pair of lens support portions 20LS on the upper surface 20us. The first submount portion 20p1 has the above-mentioned U-shaped shape extending in the Z direction. The first submount part 20p1 may be formed of, for example, a ceramic including at least one selected from the group consisting of AlN, SiC, and alumina, and an alloy such as CuW. The second submount part 20p2 is fixed to the upper surface 20us of the first submount part 20p1 and is located between the pair of lens supports 20LS. The second submount part 20p2 has a main plane 20s1 on which the laser diode chip 10 is mounted, and a front end face 20fe facing the collimating lens 30. The main plane 20s1 is the surface of the first submount part 20p1 opposite to the surface fixed to the upper surface 20us. In the present disclosure, the front end face 20fe and the back surface 20s2 do not need to be directly connected. In the present disclosure, one side of the front end face 20fe is in contact with one side of the main plane 20s1, and the side where the front end face 20fe is in contact with the main plane 20s1 defines the edge 20ed of the main plane 20s1. If the thermal conductivity of the second submount part 20p2 is higher than that of the first submount part 20p1, the heat generated from the laser diode chip 10 can be efficiently transferred to the outside. The second submount part 20p2 may be formed of at least one selected from the group consisting of, for example, Cu, Al, Ag, Fe, Ni, Mo, Cu, W, CuW, CuMo, AlN, SiC, and alumina.The size of the second submount portion 20p2 in the X direction is, for example, 0.5 mm to 1.5 mm, the size in the Y direction is, for example, 0.1 mm to 0.5 mm, and the size in the Z direction is, for example, 1 mm to 6 mm.

[0045] In this submount 20, the position of the second submount part 20p2 can be adjusted on the first submount part 20p1 by the first submount part 20p1 and the second submount part 20p2, which are separate bodies. As in this submount 20, a part having the main plane 20s1 and a part having a pair of lens support parts 20LS may be separate bodies. In this submount 20, a gap 20g exists between each of the pair of lens support parts 20LS and the second submount part 20p2. The size of the gap 20g in the X direction is, for example, 50 μm or more and 300 μm or less. The sizes of the gap 20g in the Y direction and the Z direction are determined by the sizes of the second submount part 20p2 in the Y direction and the Z direction, respectively. As with the laser light source 120 in the second modification of the first embodiment, the gap 20g can reduce the influence of heat on the laser diode chip 10 when the collimator lens 30 is bonded to the end faces 20se of the pair of lens support parts 20LS.

[0046] Next, with reference to FIG. 6A to FIG. 6C, a configuration example of the laser light source 140 in the modified example 4 of the embodiment 1 of the present disclosure will be described. FIG. 6A is a perspective view that shows a schematic configuration example of the laser light source 140 in the modified example 4 of the embodiment 1 of the present disclosure. In FIG. 6A, the laser diode chip 10, the submount 20, and the collimator lens 30 are illustrated in a separated state, but in reality, they are joined together. FIG. 6B is a top view that shows a schematic configuration of the laser light source 140 in FIG. 6A. FIG. 6C is a VIC-VIC line cross-sectional view parallel to the YZ plane of the configuration of FIG. 6B. The laser light source 140 in the modified example 4 of the embodiment 1 differs from the laser light source 100 in the embodiment 1 in the configuration of the submount 20. The submount 20 in the modified example 4 of the embodiment 1 has a through hole 20h that reaches the back surface 20s2 from the main plane 20s1, and a metal 20m that fills the through hole 20h. The portion of the submount 20 other than the through hole 20h can be formed of, for example, ceramic. The metal 20m has high thermal conductivity and may include at least one selected from the group consisting of Cu, Al, Ag, Fe, Ni, Mo, Cu, W, and CuMo. The maximum size of the metal 20m in the X direction is, for example, 0.5 mm or more and 1.5 mm or less, and the maximum size in the Z direction is, for example, 1 mm or more and 6 mm or less. The metal 20m may entirely overlap the laser diode chip 10 in top view, or may overlap only a part of it. By disposing the laser diode chip 10 in contact with the metal 20m in the submount 20, the heat generated from the laser diode chip 10 can be efficiently transferred to the semiconductor laser package 40 via the metal 20m.

[0047] Next, with reference to FIG. 7A to FIG. 7C, a configuration example of the laser light source 150 in the modified example 5 of the embodiment 1 of the present disclosure will be described. FIG. 7A is a perspective view that shows a schematic configuration example of the laser light source 150 in the modified example 5 of the embodiment 1 of the present disclosure. FIG. 7B is a top view that shows a schematic configuration example of the laser light source 150 in FIG. 7A. FIG. 7C is a cross-sectional view of the configuration of FIG. 7B along the VIIC-VIIC line parallel to the YZ plane. The laser light source 150 in the modified example 5 of the embodiment 1 is different from the laser light source 100 in the embodiment 1 in the shape of the collimator lens 30. The collimator lens 30 in the modified example 5 of the embodiment 1 has a pair of flat portions 30f and a lens curved surface portion 30c sandwiched between the pair of flat portions 30f. The lens curved surface portion 30c in the modified example 5 of the embodiment 1 functions as an FAC lens, similar to the collimator lens 30 in the embodiment 1.

[0048] Next, referring to FIG. 7D, the advantages of the pair of flat parts 30f in the collimator lens 30 will be described. FIG. 7D is a perspective view that shows a schematic view of a state in which the collimator lens 30 in the laser light source 150 in FIG. 7A is joined to the submount 20 using the collet 60. The collet 60 has a bifurcated part 60a and a support part 60b connected to the bifurcated part 60a. The collet 60 has a hollow structure and can support the collimator lens 30 by adsorbing it. Specifically, the tip part of the bifurcated part 60a in the collet 60 adsorbs the pair of flat parts 30f in the collimator lens 30. By holding the support part 60b by a mounting device and supporting the collimator lens 30 by the bifurcated part 60a, and joining the collimator lens 30 to the submount 20, a load can be applied stably in a direction perpendicular to the end faces 20se of the pair of lens support parts 20LS. With the load applied, the bonding material between the collimator lens 30 and the end faces 20se of the pair of lens support portions 20LS is heated.

[0049] A mirror (not shown) may be provided between the bifurcated portions 60a of the collet 60. The collimator lens 30 is bonded to the submount 20 while emitting laser light in the Z direction from the laser diode chip 10, and the laser light reflected in the Y direction by a mirror (not shown) is received by a light receiving device, thereby enabling accurate alignment of the collimator lens 30 with the emission end surface 10e1 of the laser diode chip 10. The light receiving device may be, for example, a power meter, a parallelism measuring device, or a beam profiler.

[0050] (Embodiment 2) Next, a basic configuration example of a laser light source according to the second embodiment of the present disclosure will be described with reference to FIGS. 8A to 8D.

[0051] FIG. 8A is a perspective view showing a configuration example of the laser light source 200 in the second embodiment of the present disclosure. FIG. 8B is a top view showing the laser light source 200 in FIG. 8A. FIG. 8C is a cross-sectional view of the configuration of FIG. 8B taken along the line VIIIC-VIIIC parallel to the YZ plane. FIG. 8D is a rear view showing the laser light source 200 in FIG. 8A. The laser light source 200 in the second embodiment differs from the laser light source 100 in the first embodiment in the configuration of the submount 20. The submount 20 in the second embodiment includes a third submount portion 20p3 and a fourth submount portion 20p4. The third submount portion 20p3 has a main plane 20s1, a back surface 20s2, and a front end surface 20fe. The fourth submount part 20p4 has a pair of lens support parts 20LS fixed to the main plane 20s1 of the third submount part 20p3, and a connecting part 20L connecting the pair of lens support parts 20LS. The connecting part 20L connects the pair of lens support parts 20LS so as not to impede the propagation of the laser light emitted from the emission end face 10e1 of the laser diode chip 10. In this submount 20, the third submount part 20p3 and the fourth submount part 20p4 are separate. As in this submount 20, the part having the main plane 20s1 and the part having the pair of lens support parts 20LS may be separate. In FIG. 8A, the third submount part 20p3, the fourth submount part 20p4, and the collimating lens 30 are illustrated in a separated state, but in reality, they are joined together. The pair of lens support portions 20LS and the connecting portion 20L in the fourth submount portion 20p4 are integrally molded.

[0052] As shown in FIG. 8B and FIG. 8C, the connecting portion 20L overlaps with the emission end surface 10e1 of the laser diode chip 10 in a top view. As shown in FIG. 8D, the fourth submount portion 20p4 is disposed on the main plane 20s1 of the third submount portion 20p3 so as to straddle the laser diode chip 10. Since the size of the fourth submount portion 20p4 in the X direction is larger than the size of the third submount portion 20p3 in the X direction, the area of ​​the end surfaces 20se of the pair of lens support portions 20LS can be increased. As a result, it becomes easy to bond the collimating lens 30 to the end surfaces 20se of the pair of lens support portions 20LS. The size of the pair of lens support portions 20LS of the fourth submount portion 20p4 in the Y direction can be approximately the same as the size of the collimating lens 30 in the Y direction. The size in the Y direction of the pair of lens support parts 20LS of the fourth submount part 20p4 may be larger than, equal to, or smaller than the size in the Y direction of the collimator lens 30. The size in the X direction of the fourth submount part 20p4 is, for example, 0.5 mm or more and 4 mm or less, the maximum size in the Y direction is, for example, 0.5 mm or more and 2 mm or less, and the size in the Z direction is, for example, 0.5 mm or more and 1 mm or less.

[0053] In the fabrication of the laser light source 200 in the second embodiment, a step of bonding the laser diode chip 10 to the main plane 20s1 of the third submount part 20p3, a step of bonding the fourth submount part 20p4 to the main plane 20s1 of the third submount part 20p3 so as to straddle the laser diode chip 10, and a step of bonding the collimating lens 30 to the end faces 20se of the pair of lens support parts 20LS in the fourth submount part 20p4 may be performed in this order. Alternatively, the fourth submount part 20p4 to which the collimating lens 30 is bonded may be bonded to the third submount part 20p3 to which the laser diode chip 10 is bonded to the main plane 20s1.

[0054] In the laser light source 200 in the second embodiment, similarly to the laser light source 100 in the first embodiment, the submount 20 supports the laser diode chip 10 by the main plane 20s1 between the pair of lens support parts 20LS, and supports the collimator lens 30 by the end face 20se of the pair of lens support parts 20LS. This makes it easy to align the laser diode chip 10 and the collimator lens 30, and makes it possible to realize a small-sized laser light source 200. Furthermore, in the laser light source 200 in the second embodiment, similarly to the laser light source 100 in the first embodiment, even if the laser diode chip 10 is placed face-down on the submount 20, it is possible to prevent the bonding material from rising up to the emission end face 10e1 of the laser diode chip 10.

[0055] (Modification of the second embodiment) Next, modified example 1 and modified example 2 of the laser light source 200 according to the second embodiment of the present disclosure will be described. Descriptions that overlap with those described above may be omitted.

[0056] A configuration example of the laser light source 210 in Modification 1 of the embodiment 2 of the present disclosure will be described with reference to FIG. 9A to FIG. 9D. FIG. 9A is a perspective view that shows a schematic configuration example of the laser light source 210 in Modification 1 of the embodiment 2 of the present disclosure. FIG. 9B is a top view that shows a schematic configuration example of the laser light source 210 in FIG. 9A. FIG. 9C is a cross-sectional view of the configuration of FIG. 9B along the line IXC-IXC parallel to the YZ plane. FIG. 9D is a rear view that shows a schematic configuration example of the laser light source 210 in FIG. 9A. The laser light source 210 in Modification 1 of the embodiment 2 differs from the laser light source 200 in the embodiment 2 in the shape of the fourth submount portion 20p4 in the submount 20. The fourth submount portion 20p4 in Modification 1 of the embodiment 2 has a notch 20co between a pair of lens supports 20LS in the fourth submount portion 20p4 in the embodiment 2. As shown in FIG. 9B and FIG. 9C, the notch 20co prevents the coupling portion 20L from overlapping with the emission end surface 10e1 of the laser diode chip 10 in top view. The size of the notch 20co in the X direction is, for example, 0.2 mm or more and 3 mm or less, and the size in the Z direction is, for example, 0.5 mm or more and 1 mm or less. The size of the notch 20co in the Z direction is larger than the size in the Z direction between the end surfaces 20se of the pair of lens supports 20LS and the edge 20ed of the main plane 20s1 of the third submount portion 20p3. In the manufacture of the laser light source 210 in the first modification of the second embodiment, the notch 20co facilitates the alignment of the emission end surface 10e1 of the laser diode chip 10 with the fourth submount portion 20p4 and the alignment of the emission end surface 10e1 of the laser diode chip 10 with the collimator lens 30.

[0057] Next, with reference to Figs. 10A to 10D, a configuration example of the laser light source 220 in Modification 2 of the embodiment 2 of the present disclosure will be described. Fig. 10A is a perspective view that shows a schematic configuration example of the laser light source 220 in Modification 2 of the embodiment 2 of the present disclosure. Fig. 10B is a top view that shows a schematic configuration example of the laser light source 220 in Fig. 10A. Fig. 10C is a cross-sectional view of the XC-XC line parallel to the YZ plane of the configuration in Fig. 10B. Fig. 10D is a perspective view that shows a schematic configuration example of the fourth sub-mount part 20p4 and the collimating lens 30 shown in Fig. 10A. The laser light source 220 in Modification 2 of the embodiment 2 is different from the laser light source 200 in the embodiment 2 in the fourth sub-mount part 20p4 of the sub-mount 20 and the collimating lens 30. As shown in Fig. 10D, the fourth sub-mount part 20p4 and the collimating lens 30 in Modification 2 of the embodiment 2 are integrally molded. Since there is no need to bond the fourth submount part 20p4 and the collimating lens 30, the size in the X direction of the fourth submount part 20p4 in the second modification of the second embodiment does not need to be as large as the size in the X direction of the fourth submount part 20p4 in the second modification of the second embodiment. The size in the X direction of the fourth submount part 20p4 in the second modification of the second embodiment is, for example, 0.2 mm or more and 3 mm or less, the maximum size in the Y direction is, for example, 0.3 mm or more and 1 mm or less, and the size in the Z direction is, for example, 0.5 mm or more and 1 mm or less.

[0058] The integrally molded fourth submount part 20p4 and collimating lens 30 may be made of at least one of glass, quartz, synthetic quartz, sapphire, transparent ceramic, and plastic. If the integrally molded fourth submount part 20p4 and collimating lens 30 are transparent, alignment between the emission end surface 10e1 of the laser diode chip 10 and the collimating lens 30 becomes easy.

[0059] The components in the above-described embodiments and their modifications may be combined in any manner.

[0060] (Application example) The laser light source of the present disclosure can be used, for example, as a light source of a direct diode laser that combines multiple laser beams to increase output. The beam combination is performed by accurately combining the laser beams emitted from multiple laser light sources. A high-intensity laser beam with a wavelength of 570 nm or less makes it easy to process metals such as copper. In the laser light source of the present disclosure, the positional deviation between the laser diode chip and the lens is unlikely to occur, so that the direction of the optical axis of the laser light emitted to the outside from the laser light source does not deviate significantly. It is possible to accurately combine the laser beams emitted from multiple laser light sources to improve the beam quality. [Industrial Applicability]

[0061] The laser light sources of the present disclosure may also be used in projectors and lighting fixtures, for example. [Explanation of symbols]

[0062] 10 Laser Diode Chip 10a Semiconductor laminated structure 10b Board 10C1 First cladding layer 10C2 Second Cladding Layer 10e1 output end face 10e2 rear end face 10L Light-emitting layer 20 Submount 20co cutout 20d groove 20ed Edge 20fe front end 20fe1 center end face 20fe2 both end faces 20L connection part 20LS Lens support 20p1 1st submount part 20p2 second submount part 20p3 3rd submount part 20p4 4th submount part 20s1 main plane 20s2 back side 20se End faces of a pair of lens supports 20us Top surface of the first submount 30 Collimating Lens 30c Lens curved surface 30f flat area 40 Semiconductor laser package 40b Base 40L lid body 40w transparent window 50 Lead terminal 60 Colette 60a Fork part 60b Support part 100, 110, 120, 130, 140, 150 Laser light source 200, 210, 220 Laser light source

Claims

1. an edge-emitting type laser diode chip having a semiconductor laminated structure including a light-emitting layer, a first end face for emitting laser light generated in the light-emitting layer, and a second end face opposite to the first end face, the edge-emitting type laser diode chip having a cavity length defined by a distance from the first end face to the second end face; a submount having a main surface to which the laser diode chip is fixed and a back surface located opposite to the main surface; a pair of lens support portions disposed on the main plane of the submount and positioned on both sides of the first end face of the laser diode chip; a connecting portion that connects the pair of lens support portions so as not to interfere with the propagation of the laser light emitted from the first end face of the laser diode chip and that overlaps with the first end face of the laser diode chip in a top view; a lens bonded to the end faces of the pair of lens support parts; a semiconductor laser package that accommodates the laser diode chip, the lens, the pair of lens support portions, the connecting portion, and the submount; Equipped with the first end face of the laser diode chip protrudes beyond an edge of the main plane in a direction of the cavity length; the end faces of the pair of lens support parts protrude in the direction of the cavity length beyond the first end face of the laser diode chip, The pair of lens support portions and the connecting portion are integrally molded.

2. 2. The laser light source according to claim 1, wherein the semiconductor laser package has a base in thermal contact with the back surface of the submount, hermetically sealing the laser diode chip, the submount, and the lens.

3. the submount has a front end surface connecting the main surface and the back surface; The front end surface has a central end surface and side end surfaces located on both sides of the central end surface, the central end face is recessed in a direction of the cavity length from the two side end faces, The laser light source according to claim 1 , wherein the edge of the main plane is defined by the main plane and the central end face of the submount.

4. 3. The laser light source according to claim 1, wherein the submount has grooves extending along the direction of the cavity length between the laser diode chip and each of the pair of lens supports.

5. The laser light source according to claim 1 , wherein the lens is bonded to the end faces of the pair of lens support parts by an inorganic material.

6. The laser light source according to claim 1 , wherein a part or the whole of the submount is made of ceramic.

7. The laser light source according to claim 6 , wherein the submount has a through hole extending from the main surface to the rear surface, and a metal filling the through hole.

8. The laser light source according to claim 1 , wherein a center of gravity of the lens is located between the pair of lens support parts when viewed from the direction of the resonator length.

9. The laser light source according to claim 1 , wherein the wavelength of the laser light is not less than 350 nm and not more than 570 nm.

10. the lens has a structure extending along a direction perpendicular to both a normal direction of the principal plane and a direction of the cavity length, The laser light source according to claim 1 , wherein the lens reduces a divergence angle of the laser light in a plane including both a normal direction to the principal plane and a direction of the cavity length.

11. The laser light source according to claim 1 , wherein the lens has a pair of flat portions and a lens curved surface portion sandwiched between the pair of flat portions.

12. The laser light source according to claim 1 , wherein the pair of lens support portions, the connecting portion, and the lens are integrally molded.

Images