JP2018170431A - Semiconductor laser device and manufacturing method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor laser device capable of suppressing unnecessary power consumption and improving a manufacturing yield, and a manufacturing method for the semiconductor laser device.SOLUTION: A semiconductor laser device 1 includes: a plurality of semiconductor laser elements LD1 to LD11; and a coupling optical system (F-axis collimating lenses FAC1 to FAC11, S-axis collimating lenses SAC1 to SAC11, and double mirrors M1 to M11, an F axis condensing lens FL, and an S axis condensing lens SL) that couples laser light emitted from the plurality of semiconductor laser elements LD1 to LD11 to one optical fiber OF. At least one of the plurality of semiconductor laser elements LD1 to LD11 (the semiconductor laser element LD5) is brought into a light emission impossible state which is electrically short-circuited or insulated by a wire W1 and cannot emit light.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a semiconductor laser device and a manufacturing method thereof.

  A semiconductor laser device generally includes a semiconductor laser element, a collimating lens, and a condensing optical system. The laser light emitted from the semiconductor laser is collimated by a collimating lens and then condensed by a condensing optical system. Output. When one end of the optical fiber is disposed at the output portion of the semiconductor laser device, the laser light output from the semiconductor laser device is coupled to the optical fiber.

  Further, a semiconductor laser device that requires high output includes a plurality of semiconductor laser elements and collimating lenses according to the required output. In such a semiconductor laser device, the laser light emitted from each of the semiconductor laser elements is individually collimated by a collimating lens provided corresponding to each of the semiconductor laser elements, and a plurality of collimated laser lights are collected. Light is collected by the optical optical system and output to the outside (or coupled to an optical fiber).

  Patent Document 1 below discloses an example of a conventional semiconductor laser device including a plurality of semiconductor laser elements. Specifically, the following Patent Document 1 includes 10 LD chips as semiconductor laser elements, 10 F-axis collimating lenses and S-axis collimating lenses as collimating lenses, and F-axis focusing as a condensing optical system. A lens and an S-axis condensing lens, in addition to ten double mirrors, collimate and reflect the laser light emitted from the ten LD chips individually, and then condense to collect one optical fiber. A semiconductor laser device to be coupled to is disclosed.

Japanese Patent No. 5717714

  By the way, in the semiconductor laser device disclosed in Patent Document 1 described above, extremely high mounting accuracy is required for optical components (collimator lenses, mirrors, condensing optical systems) used for coupling laser beams. For example, a submicron mounting accuracy is required for a collimating lens. At the time of manufacturing the semiconductor laser device, the positions of the optical components are fixed after the optical components are positioned so that the mounting accuracy falls within the target accuracy. However, when manufacturing a semiconductor laser device, due to dimensional tolerance of each optical component and variations in the curing method of an adhesive (for example, a thermosetting resin or an ultraviolet curable resin) used to fix each optical component, etc. A positional deviation exceeding the target accuracy may occur.

  Here, some of the optical components (collimating lenses and mirrors) used for coupling the laser light are provided corresponding to the semiconductor laser elements. Therefore, if the number of semiconductor laser elements is small, the number of optical components decreases. It is considered that it is relatively easy to keep the mounting accuracy of each optical component within the target accuracy. However, in semiconductor laser devices that require high output, the number of semiconductor laser elements tends to increase, and along with this, the number of optical components used for laser beam coupling also tends to increase. For this reason, in a semiconductor laser device that requires high output, it is difficult to keep the mounting accuracy of all optical components within the target accuracy. If an optical component with poor mounting accuracy is present in the manufactured semiconductor laser device, there is a problem that the coupling efficiency with respect to the optical fiber is deteriorated.

  In addition, regarding the above-described optical component provided in the semiconductor laser device, it may be considered that an appearance problem (for example, chipping or adhesion of foreign matter) occurs erroneously at the time of manufacturing the semiconductor laser device. If there is an optical component with such an appearance problem, the laser beam incident on the optical component may be scattered, or optical component misalignment or the like may occur due to the absorption and heat generation of a foreign material exceeding the resin glass transition temperature. Therefore, the coupling efficiency to the optical fiber is significantly deteriorated. For this reason, the manufactured semiconductor laser device becomes defective and there is a problem that the yield is lowered.

  Here, when the coupling efficiency of the semiconductor laser device with respect to the optical fiber is decreased, useless laser light that is not coupled to the optical fiber is increased among the light emitted from the semiconductor laser element. For this reason, when trying to obtain a constant output from the optical fiber, it is necessary to supply more power to the semiconductor laser device when the coupling efficiency to the optical fiber is lower than when the coupling efficiency is high. There is a problem of being done.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a semiconductor laser device and a manufacturing method thereof that can suppress wasteful power consumption and can improve manufacturing yield.

In order to solve the above problems, a semiconductor laser device of the present invention includes a plurality of semiconductor laser elements (LD1 to LD11) and laser light emitted from the plurality of semiconductor laser elements into one optical fiber (OF). In a semiconductor laser device (1-3) comprising coupling optical systems (FAC1 to FAC11, SAC1 to SAC11, M1 to M11, FL, SL) to be coupled, at least one of the plurality of semiconductor laser elements is conductive The member (ST, W1, W2) is electrically short-circuited or insulated so that it cannot emit light.
Further, the semiconductor laser device of the present invention has the worst coupling efficiency of the laser beam to the optical fiber when the semiconductor laser element in the non-light emitting state emits light among the plurality of semiconductor laser elements. is there.
Further, in the semiconductor laser device of the present invention, the plurality of semiconductor laser elements are arranged adjacent to each other, and the semiconductor laser element (LD5) in which the light emission is disabled is adjacent on one side. When the positive electrode (13) of the element (LD4) and the negative electrode (12) of the semiconductor laser element (LD6) adjacent on the other side are connected by the conductive wiring (W1), an electrical short circuit or Insulated.
Alternatively, in the semiconductor laser device according to the present invention, the plurality of semiconductor laser elements are arranged adjacent to each other, and the semiconductor laser element in the non-light emitting state includes a positive electrode (13) and a negative electrode (12). Are connected by the conductive wiring (W2), or the positive electrode (13) and the negative electrode (12) are covered with the conductive sheet (ST) to be electrically short-circuited.
In the semiconductor laser device of the present invention, the plurality of semiconductor laser elements are electrically connected in series by connecting the positive electrode (13) and the negative electrode (12) of the adjacent semiconductor laser element by a wiring (W). It is connected.
A method of manufacturing a semiconductor laser device according to the present invention includes a plurality of semiconductor laser elements (LD1 to LD11) and a coupling optical system that couples laser light emitted from the plurality of semiconductor laser elements to one optical fiber (OF). (FAC1 to FAC11, SAC1 to SAC11, M1 to M11, FL, SL), a first step (S11, S14) for arranging and fixing on the substrate, and the fixed coupling optical system A second step (S15) of measuring the laser beam through at least a part, and referring to the measurement result of the second step, the light emission disabled state in which at least one of the plurality of semiconductor laser elements cannot emit light And a third step (S16) for determining whether or not to perform.
Further, in the method of manufacturing a semiconductor laser device according to the present invention, the second step is emitted from the plurality of semiconductor laser elements in a state where all of the plurality of semiconductor laser elements electrically connected in series are emitted. In this step, only one of the laser beams is incident on the coupling optical system in order, and the laser beam is measured via at least a part of the coupling optical system.
In the method for manufacturing a semiconductor laser device according to the present invention, at least one of the plurality of semiconductor laser elements is electrically connected by a conductive member (W1, W2, ST) based on the determination result of the third step. It further includes a fourth step (S17) in which the light emission is disabled by short-circuiting or insulating.
Further, in the method of manufacturing a semiconductor laser device according to the present invention, the fourth step is adjacent on one side of the semiconductor laser element (LD5) in which the light emission is disabled among the semiconductor laser elements arranged adjacently. Electrically connecting the positive electrode (13) of the semiconductor laser element (LD4) to the negative electrode (12) of the semiconductor laser element (LD6) adjacent on the other side by a conductive wiring (W1). This is a process of short-circuiting or insulating.
Alternatively, in the method of manufacturing a semiconductor laser device according to the present invention, the fourth step includes negative and positive electrodes (13) of the semiconductor laser element that are not allowed to emit light among the semiconductor laser elements arranged adjacently. It is a step of electrically short-circuiting the electrode (12) by connecting the conductive wire (W2) or covering the positive electrode (13) and the negative electrode (12) with a conductive sheet (ST). .

  According to the present invention, at least one of the plurality of semiconductor laser elements is electrically short-circuited or insulated by the conductive member so that it cannot emit light. Thus, for example, by making the laser beam having the worst coupling efficiency non-emissionable, it is possible to increase the overall coupling efficiency of the laser beam to the optical fiber. As a result, wasteful power consumption can be suppressed, and the manufacturing yield can be improved.

1 is a plan view of a semiconductor laser device according to a first embodiment of the present invention. It is a front view which shows an example of the connection state of the semiconductor laser element made into the light emission disabled state in 1st Embodiment of this invention. It is a front view which shows the other example of the connection state of the semiconductor laser element made into the light emission disabled state in 1st Embodiment of this invention. It is a perspective view which shows the structure of the double mirror provided in the semiconductor laser apparatus by 1st Embodiment of this invention. 5 is a flowchart showing an example of a method of manufacturing the semiconductor laser device according to the first embodiment of the present invention. It is a top view for demonstrating the measurement process of the reflected laser beam using the optical monitor apparatus in 1st Embodiment of this invention. In 1st Embodiment of this invention, it is a figure which shows an example of the reflected laser beam which injects into an optical monitor apparatus. It is a figure which shows the structure of the semiconductor laser apparatus by 2nd Embodiment of this invention. It is sectional drawing of the semiconductor laser apparatus by 3rd Embodiment of this invention. It is a front view of the semiconductor laser apparatus by 3rd Embodiment of this invention.

  Hereinafter, a semiconductor laser device and a manufacturing method thereof according to embodiments of the present invention will be described in detail with reference to the drawings. In the following, for easy understanding, the positional relationship of each member will be described with reference to the XYZ orthogonal coordinate system (the position of the origin is changed as appropriate) set in the drawing as necessary. Further, in the drawings referred to below, the dimensions of each member are appropriately changed as necessary for easy understanding.

[First Embodiment]
<Semiconductor laser device>
FIG. 1 is a plan view of a semiconductor laser device according to a first embodiment of the present invention. As shown in FIG. 1, the semiconductor laser device 1 of the present embodiment includes a substrate B, (N + 1) (N = 10 in this embodiment) semiconductor laser elements LD1 to LD11, and (N + 1) F-axis collimating lenses FAC1. FAC11, (N + 1) S-axis collimating lenses SAC1 to SAC11, (N + 1) double mirrors M1 to M11, F-axis focusing lens FL, and S-axis focusing lens SL, and a semiconductor laser element The laser light emitted from the LD1 to LD11 is collimated (converted into parallel light) and then condensed and coupled to the optical fiber OF.

  In the XYZ orthogonal coordinate system shown in FIG. 1, the + Z direction of the Z axis is set as the laser light emission direction. The X axis of the XYZ orthogonal coordinate system is set to be parallel to the direction (slow axis) parallel to the pn junction surface of the semiconductor laser elements LD1 to LD11, and the Y axis is the pn of the semiconductor laser elements LD1 to LD11. It is set to be parallel to the direction (fast axis) perpendicular to the joint surface.

  The substrate B includes the above-described semiconductor laser elements LD1 to LD11 and a coupling optical system (F-axis collimating lenses FAC1 to FAC11, S-axis collimating lenses SAC1 to SAC11, double mirrors M1 to M11, F-axis condensing lenses FL, and S The axial condensing lens SL) is a rectangular plate-like member that is mounted directly or via a mount (not shown). The substrate B is formed using a material having a high thermal conductivity in order to increase the heat radiation efficiency of the semiconductor laser elements LD1 to LD11 and a low thermal expansion coefficient in order to reduce the stress caused by the temperature change as much as possible. For example, ceramics such as aluminum nitride (AlN) or metals such as molybdenum (Mo) are suitable.

  The semiconductor laser elements LD1 to LD11 are arranged on the substrate B with a constant interval along the direction parallel to the X axis with the laser beam emitting part directed to the + Z side. These semiconductor laser elements LD1 to LD11 emit laser light in the + Z direction when a drive current is supplied from a drive circuit (not shown). The wavelength of the laser light emitted from these semiconductor laser elements LD1 to LD11 is, for example, the 0.9 μm band. The semiconductor laser elements LD1 to LD11 are mounted on the substrate B so that the pn junction surfaces are parallel to the ZX plane.

  In the semiconductor laser elements LD1 to LD11, adjacent positive electrodes (anode electrodes) and negative electrodes (cathode electrodes) are connected by wires W (wiring) and electrically connected in series. For example, the anode electrode of the semiconductor laser element LD1 and the cathode electrode of the semiconductor laser element LD2 are connected by a wire W, and the anode electrode of the semiconductor laser element LD2 and the cathode electrode of the semiconductor laser element LD3 are connected by a wire W. However, as will be described in detail later, a semiconductor laser element (including a state in which no current flows between the anode and the cathode and a state in which light is short-circuited and light cannot be emitted) is included (see FIG. 1). In the example shown in FIG. 2, the semiconductor laser element LD5) is not connected by the wire W.

  Here, of the semiconductor laser elements LD1 to LD11, N semiconductor laser elements are inherently provided in the semiconductor laser device 1, and the remaining one semiconductor laser element is a laser beam for the optical fiber OF. It is provided in order to increase the coupling efficiency. That is, N semiconductor laser elements among the semiconductor laser elements LD1 to LD11 are under the condition that the coupling efficiency of the laser light emitted from each of the semiconductor laser elements LD1 to LD11 exceeds a predetermined reference value. It is provided so that laser light with a power higher than the rating (for example, 100 [W]) is output from the semiconductor laser device 1 when a rated drive current is supplied to each.

  On the other hand, the remaining one semiconductor laser element does not satisfy the above-mentioned conditions for the N semiconductor laser elements, and when the coupling efficiency with respect to the optical fiber OF is reduced, for example, the optical fiber OF Is provided in order to increase the overall coupling efficiency to the optical fiber OF. The reduction in the coupling efficiency with respect to the optical fiber OF is caused by, for example, the presence of an optical component with poor mounting accuracy among the optical components forming the above-described coupling optical system, or an optical component having a problem in appearance (for example, chipping or adhesion of foreign matter). Caused by the presence of

  For example, consider the case where the mounting accuracy of the double mirror M5 is poor and the coupling efficiency of the laser light emitted from the semiconductor laser element LD5 to the optical fiber OF is reduced. In such a case, as shown in FIG. 1, the semiconductor laser element LD5 is disabled from the above-described light emission, and any one of the semiconductor laser elements LD1 to LD4 and LD6 to LD11 is the so-called semiconductor laser element LD5. Used as an alternative. Here, to make the semiconductor laser element LD5 in which the coupling efficiency of the laser beam to the optical fiber OF has been lowered not to emit light, the overall coupling efficiency to the optical fiber OF is increased, and the semiconductor laser element LD5 This is to prevent wasteful power consumption by eliminating the drive current that contributes to light emission even if the drive current is not supplied or even if the drive current is supplied to the semiconductor laser element LD5.

  FIG. 2 is a front view showing an example of a connection state of the semiconductor laser elements that are in a light emission disabled state in the first embodiment of the present invention. In FIG. 2, the semiconductor laser elements LD4 and LD6 adjacent to the semiconductor laser element LD5 which is set to the light emission disabled state are also illustrated. As shown in FIG. 2, the semiconductor laser elements LD <b> 4 to LD <b> 6 include a laser mount 11, electrode chips 12 and 13, a semiconductor laser chip 14, and a conductive wire 15. The other semiconductor laser elements (semiconductor laser elements LD1 to LD3, LD7 to LD11) have the same configuration.

  The laser mount 11 is a rectangular parallelepiped member on which the electrode chips 12 and 13 and the semiconductor laser chip 14 are mounted. The electrode chips 12 and 13 are members that are external electrodes of the semiconductor laser chip 14 and are mounted on the laser mount 11 in a state of being electrically insulated from each other. The semiconductor laser chip 14 has an upper surface as one electrode (for example, an anode electrode) and a bottom surface as the other electrode (for example, a cathode electrode), and a drive current is supplied between the electrodes on the upper surface and the bottom surface. An element that emits laser light.

  The semiconductor laser chip 14 is mounted on the electrode chip 12 with its bottom surface conducting to the electrode chip 12. Further, the upper surface of the semiconductor laser chip 14 and the electrode chip 13 are connected by a conductive wire 15. For this reason, the electrode chip 12 is used as a cathode electrode as an external electrode of the semiconductor laser chip 14, for example, and the electrode chip 13 is used as an anode electrode as an external electrode of the semiconductor laser chip 14, for example. Thus, for example, if the electrode chip 12 is connected to the positive electrode of the DC power supply and the electrode chip 13 is connected to the negative electrode of the DC power supply, the DC current is applied to the electrode chip 12, the semiconductor laser chip 14, the conductive wire 15, and the electrode chip 13. As a result, laser light is emitted from the semiconductor laser chip 14.

  As described above, in the semiconductor laser elements (semiconductor laser elements LD1 to LD4 and LD6 to LD11) other than the semiconductor laser element (semiconductor laser element LD5) which is disabled from emitting light, the anode electrode and the cathode electrode of the adjacent ones are wires W. Connected by. Therefore, the electrode chip 12 as the cathode electrode of the semiconductor laser element LD4 is connected to the electrode chip 13 (not shown in FIG. 2) as the anode electrode of the semiconductor laser element LD3 by the wire W. Similarly, an electrode chip 13 as an anode electrode of the semiconductor laser element LD6 is connected to an electrode chip 12 (not shown in FIG. 2) as a cathode electrode of the semiconductor laser element LD7 by a wire W.

  On the other hand, as shown in FIG. 2, the semiconductor laser element LD5 in a state incapable of emitting light is not connected to any of the adjacent semiconductor laser elements LD4 and LD6, and is an electrode chip as an anode electrode of the semiconductor laser element LD4. 13 and the electrode chip 12 as the cathode electrode of the semiconductor laser element LD6 are connected by a wire W1 (conductive member, conductive wiring) in a state of jumping over the semiconductor laser element LD5. As described above, the semiconductor laser element LD5 that is set to the light emission disabled state is electrically insulated from the other semiconductor laser elements (semiconductor laser elements LD1 to LD4, LD6 to LD11).

  The semiconductor laser elements LD1 to LD4 and LD6 to LD11 excluding the semiconductor laser element LD5 are connected in series by the above connections using the wires W and W1. For this reason, the electrode chip 12 as the cathode electrode of the semiconductor laser element LD1 is connected to the negative electrode of the drive circuit (not shown), and the electrode chip 13 as the anode electrode of the semiconductor laser element LD11 is connected to the positive electrode of the drive circuit (not shown). For example, laser light is emitted from the semiconductor laser elements (semiconductor laser elements LD1 to LD4, LD6 to LD11) excluding the semiconductor laser element (semiconductor laser element LD5) that is in a light emission disabled state.

  FIG. 3 is a front view showing another example of the connection state of the semiconductor laser elements that are in the light emission disabled state in the first embodiment of the present invention. In FIG. 3, the same members as those shown in FIG. 2 are denoted by the same reference numerals. In the example shown in FIG. 2, the semiconductor laser element LD5 that is disabled from light emission is electrically insulated from the other semiconductor laser elements (semiconductor laser elements LD1 to LD4, LD6 to LD11). On the other hand, in the example shown in FIG. 3, the semiconductor laser element LD <b> 5 that is set in the light emission disabled state is electrically short-circuited.

  First, in the example shown in FIGS. 3A to 3C, all the semiconductor laser elements (semiconductor laser elements LD1 to LD11) have an anode electrode and a cathode electrode connected to each other by a wire W. This is different from the example shown in FIG. In other words, the semiconductor laser element LD5 that is disabled from light emission is also connected to the adjacent semiconductor laser elements LD4 and LD6 by the wire W. Specifically, the electrode chip 12 as the cathode electrode of the semiconductor laser element LD5 and the electrode chip 13 as the anode electrode of the semiconductor laser element LD4 are connected by the wire W, and the anode of the semiconductor laser element LD5 that is in a light emission disabled state. The electrode chip 13 as an electrode and the electrode chip 12 as a cathode electrode of the semiconductor laser element LD6 are connected by a wire W.

  In the example shown in FIG. 3A, after the connection by the wire W is made, the electrode chip 13 as the anode electrode of the semiconductor laser element LD4 and the electrode chip 12 as the cathode electrode of the semiconductor laser element LD6 are The semiconductor laser element LD5 is connected by a wire W1 so as to jump over the semiconductor laser element LD5. With this connection, the semiconductor laser elements LD4 and LD6 are connected in series by the wire W1, and the anode electrode and the cathode electrode of the semiconductor laser chip 14 are short-circuited by the wire W1. The element LD5 is in a light emission disabled state.

  In the example shown in FIG. 3B, the conductive sheet ST (conductive member) is pressure-bonded to the upper surface of the semiconductor laser element LD5 after the connection by the wire W is made. Specifically, the conductive sheet ST is pressure-bonded to the upper surface of the semiconductor laser element LD5 so as to cover the upper surfaces of the electrode chips 12, 13 forming the semiconductor laser element LD5 and the upper surface of the semiconductor laser chip 14. The conductive sheet ST only needs to be pressure-bonded to the upper surface of the semiconductor laser element LD5 so as to cover at least the upper surface of the semiconductor laser chip 14 forming the semiconductor laser element LD5 and the upper surface of the electrode chip 12.

  As the conductive sheet, a sheet having good heat conductivity and conductivity (for example, a gold foil, a silver foil, a copper foil, a pure indium foil, a sheet made of indium (In) tin (Sn)) can be used. When the conductive sheet ST is pressed, the semiconductor laser elements LD4 and LD6 are connected in series by the wire W1, and the anode electrode and the cathode electrode of the semiconductor laser chip 14 are short-circuited by the conductive sheet ST. As a result, the semiconductor laser element LD5 becomes incapable of emitting light.

  In the example shown in FIG. 3C, after the connection by the wire W is made, the upper surface of the semiconductor laser chip 14 of the semiconductor laser element LD4 and the electrode chip 12 are connected to the wire W2 (conductive member, conductive wiring). Connected by. By making such a connection, the semiconductor laser elements LD4 and LD6 are connected in series by the wires W and W2, and the anode electrode and the cathode electrode of the semiconductor laser chip 14 are short-circuited by the wire W2. The semiconductor laser element LD5 is in a state incapable of emitting light.

  The F-axis collimating lenses FAC1 to FAC11 are arranged on the + Z side of the semiconductor laser elements LD1 to LD11, respectively, and collimate the components of the F axis (fast axis) of the laser light emitted from the semiconductor laser elements LD1 to LD11. The S-axis collimating lenses SAC1 to SAC11 are arranged on the + Z side of the F-axis collimating lenses FAC1 to FAC11, respectively, and collimate the S-axis (slow axis) components of the laser light emitted from the semiconductor laser elements LD1 to LD11. If the spread of the laser light emitted from the semiconductor laser elements LD1 to LD11 in the S-axis direction is sufficiently small, the S-axis collimating lenses SAC1 to SAC11 can be omitted.

  The double mirrors M1 to M11 are provided corresponding to each of the semiconductor laser elements LD1 to LD11, and are respectively disposed on the + Z side of the S-axis collimating lenses SAC1 to SAC11, and pass through the S-axis collimating lenses SAC1 to SAC11. The laser light is individually reflected toward the F-axis condenser lens FL (in the −X direction). Specifically, the double mirrors M1 to M11 reflect the laser light via the S-axis collimating lenses SAC1 to SAC11 in the + Y direction and then in the −X direction, respectively. The laser beams collimated by the F-axis collimating lenses FAC1 to FAC11 are densely arranged by being reflected by the double mirrors M1 to M11. That is, the double mirrors M1 to M11 have a role of placing the laser beams collimated by the F-axis collimating lenses FAC1 to FAC11 in a range where they can be closely arranged and coupled to the optical fiber OF.

  FIG. 4 is a perspective view showing a configuration of a double mirror provided in the semiconductor laser device according to the first embodiment of the present invention. As shown in FIG. 4, the double mirror M (M1 to M11) includes a first mirror m1 and a second mirror m2. The first mirror m1 is a polyhedral member having at least a bottom surface A1, a top surface B1 parallel to the bottom surface A1, and a reflection surface S1. Note that the angle formed by the reflecting surface S1 and the bottom surface A1 is 45 ° as shown in FIG.

  The first mirror m1 is placed on the substrate B so that the bottom surface A1 contacts the top surface of the substrate B. As a result, the angle formed by the normal vector of the reflection surface S1 of the first mirror m1 and the normal vector of the upper surface (ZX surface) of the substrate B becomes 45 °. The direction of the first mirror m1 is set so that the normal line of the reflecting surface S1 is parallel to the YZ plane. Thereby, the reflecting surface S1 of the first mirror m1 reflects the laser light traveling in the + Z direction in the + Y direction.

  The second mirror m2 is a polyhedral member having at least a bottom surface A2 and a reflection surface S2. The angle formed by the reflecting surface S2 and the bottom surface A2 is 45 ° as shown in FIG. The second mirror m2 is placed on the first mirror m1 such that the bottom surface A2 contacts the top surface B1 of the first mirror m1. As a result, the angle formed by the normal vector of the reflecting surface S2 of the second mirror m2 and the normal vector of the upper surface (ZX surface) of the substrate B becomes 135 °. The direction of the second mirror m2 is set so that the normal line of the reflecting surface S2 is substantially parallel to the XY plane. Thereby, the reflecting surface S2 of the second mirror m2 reflects the laser light traveling in the + Y direction in the approximately −X direction.

  Here, when the first mirror m1 is slightly rotated around the Y axis, the propagation direction of the laser beam reflected by the double mirror M and directed substantially in the −X direction is slightly rotated around the Z axis. Further, when the second mirror m2 is slightly rotated around the Y axis, the propagation direction of the laser light reflected by the double mirror M and directed substantially in the −X direction is slightly rotated around the Y axis. As described above, in the double mirror M, the propagation direction of the laser light toward the substantially −X direction can be changed by appropriately setting the directions of the first mirror m1 and the second mirror m2.

  The F-axis condenser lens FL is provided on the optical path of the laser light between the double mirrors M1 to M11 and the optical fiber OF, and the laser light reflected in the substantially −X direction by the double mirrors M1 to M11, The distance is refracted so that the interval is minimized (preferably 0) at the incident end face of the optical fiber OF. The S-axis condensing lens SL is provided on the optical path of the laser light between the F-axis condensing lens FL and the optical fiber OF, and the laser beam via the F-axis condensing lens FL has a beam diameter in the Y direction. The light is focused so as to be minimized (preferably 0) at the incident end face of the optical fiber OF.

  The optical fiber OF is disposed in a direction orthogonal to the traveling direction of the laser light emitted from the semiconductor laser elements LD1 to LD11, and the incident end surface thereof is disposed at the focal position of the S-axis condenser lens SL, for example. Is positioned. The optical fiber OF guides the laser light emitted from each of the semiconductor laser elements LD1 to LD11 to the outside of the semiconductor laser device 1. As the optical fiber OF, any optical fiber can be used depending on the application. For example, a single core fiber, a multi-core fiber, a single clad fiber, a double clad fiber, and other optical fibers can be used.

  When a drive current is supplied from a drive circuit (not shown) to the semiconductor laser device 1 having the above configuration, the supplied drive current flows to the semiconductor laser elements LD1 to LD4 and LD6 to LD11 connected in series, and these semiconductor lasers Laser light is emitted in the + Z direction from the elements LD1 to LD4 and LD6 to LD11. The semiconductor laser element LD5 does not emit light because it is electrically insulated from the semiconductor laser elements LD1 to LD4 and LD6 to LD11 connected in series.

  The laser beams emitted from the semiconductor laser elements LD1 to LD4 and LD6 to LD11 in the + Z direction are first incident on the F axis collimating lenses FAC1 to FAC4 and FAC6 to FAC11 to collimate the F axis components, respectively. The light enters the S-axis collimating lenses SAC1 to SAC4, SAC6 to SAC11, and the S-axis components are collimated. The collimated laser beams are incident on the double mirrors M1 to M4 and M6 to M11, and are individually reflected in the + Y direction and then reflected in the -X direction.

  The laser light reflected in the −X direction by the double mirrors M1 to M4 and M6 to M11 is first incident on the F-axis condenser lens FL and refracted so that the distance between them is small, and then the S-axis collection. The light beam SL enters the optical lens SL and is focused so that the beam diameter in the Y direction becomes small. Then, these laser beams are incident on the optical fiber OF at the incident end face of the optical fiber OF and the beam diameter in the Y direction is minimized (preferably zero), and propagate through the optical fiber OF. Output to the outside.

  As described above, in the semiconductor laser device 1 according to the present embodiment, at least one of the plurality of semiconductor laser elements LD1 to LD11 is electrically insulated (or short-circuited) by the wire W1 (or the conductive sheet ST or the wire W2). In this state, the light cannot be emitted. For example, among the plurality of semiconductor laser elements LD1 to LD11, the one having the lowest coupling efficiency of the laser beam to the optical fiber OF is in a light emission disabled state. As described above, since the laser beam with the lowest coupling efficiency is disabled, the overall coupling efficiency of the laser beam to the optical fiber OF can be increased. As a result, wasteful laser light that is not coupled to the optical fiber OF can be reduced, and wasteful power consumption can be suppressed.

<Method for manufacturing semiconductor laser device>
FIG. 5 is a flowchart showing an example of the manufacturing method of the semiconductor laser device according to the first embodiment of the present invention. When manufacturing of the semiconductor laser device 1 is started, first, the semiconductor laser elements LD1 to LD11, the collimating lenses (F-axis collimating lenses FAC1 to FAC11, S-axis collimating lenses SAC1 to SAC11), and the double mirrors M1 to M11 are mounted on the substrate B. A process of mounting on top is performed (process S11: first process). For the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11, for example, an ultraviolet curable resin is provided as an adhesive between the substrate B.

  Next, as shown in FIG. 6, an optical monitor device OM is installed on the substrate B, and reflected laser light (laser light reflected in the −X direction by the double mirrors M1 to M11) is used by using the optical monitor device OM. A measuring step is performed (step S12). FIG. 6 is a plan view for explaining a process of measuring reflected laser light using the optical monitor device according to the first embodiment of the present invention. The optical monitor device OM is for detecting the direction and position of the incident laser light, and is disposed on the optical path of the reflected laser light with its light receiving surface facing the + X side. Specifically, in this step, an operation is performed in which a current is supplied to the semiconductor laser elements LD1 to LD11 by a jig (not shown) to emit light in order, and the incident position of the reflected laser light with respect to the light receiving surface of the optical monitoring device OM is sequentially measured. Is called.

  Next, a step of adjusting the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11 is performed while referring to the measurement result of the optical monitor device OM (step S13). For example, for the double mirrors M1 to M11, the first mirror m1 shown in FIG. 4 is slightly rotated around the Y axis to adjust the position of the reflected laser beam in the Y direction, and the second mirror m2 is rotated around the Y axis. The operation of adjusting the position of the reflected laser light in the Z direction by performing a slight rotation is performed.

  FIG. 7 is a diagram showing an example of reflected laser light incident on the optical monitor device in the first embodiment of the present invention. In FIG. 7, a rectangular area to which a reference sign RS is attached is a light receiving surface of the optical monitor device OM. In FIG. 7, all laser beams emitted from the semiconductor laser elements LD1 to LD11 are illustrated for easy understanding. However, in actuality, since the semiconductor laser elements LD1 to LD11 are sequentially emitted to perform the above adjustment, only one laser beam is incident on the light receiving surface RS of the optical monitor device OM.

  In this step, the laser light emitted from the semiconductor laser elements LD1 to LD11 (reflected laser light incident on the optical monitor device OM) has the same position in the Y direction as shown in FIG. 7, for example, and is constant in the Z direction. The S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11 are adjusted so that they are arranged with an interval of. In addition, adjustment is performed so that the cross-sectional shape of each laser beam becomes an elliptical shape extending in the Y direction.

  When the above adjustment is completed, a step of fixing the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11 on the substrate B is performed (step S14: first step). Specifically, the ultraviolet curable resin provided between the substrate B and the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11 is irradiated with ultraviolet rays to cure the ultraviolet curable resin. Is done.

  Subsequently, a step of measuring the reflected laser beam using the optical monitor device OM is performed while causing the semiconductor laser elements LD1 to LD11 to emit light individually (step S15: second step). In the above step S14, misalignment or the like of the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11 may occur due to variations in how the ultraviolet curable resin is cured. When such misalignment or the like occurs, for example, the reflection direction of the reflected laser light changes, and the coupling efficiency of the laser light with respect to the optical fiber OF shown in FIG. 1 deteriorates. For this reason, in this step, the deterioration of the coupling efficiency due to the change in the reflection direction of the reflected laser beam is estimated by measuring the change in the irradiation position of the reflected laser beam individually using the optical monitor device OM. ing.

  When the measurement using the optical monitor device OM is completed, a step of determining whether or not at least one of the semiconductor laser elements LD1 to LD11 is in a light emission disabled state is performed based on the measurement result of the optical monitor device OM. (Step S16: Third step). For example, the measurement result after adjustment in step S13 is compared with the measurement result in step S15, and the laser beam having the largest positional deviation among the laser beams emitted from each of the semiconductor laser elements LD1 to LD11 is specified. It is determined whether or not the semiconductor laser element that emits the laser light is in a light emission disabled state. This determination may be performed automatically using, for example, a computer or may be performed manually by a human. In addition, the number of semiconductor laser elements that are disabled from light emission may be zero, or may be two or more.

  When the above steps are completed, a step of bonding the semiconductor laser elements LD1 to LD11 is performed (step S17: fourth step). For example, as shown in FIGS. 1 and 2, the anode electrode and the cathode electrode of adjacent semiconductor laser elements LD <b> 1 to LD <b> 4 and LD <b> 6 to LD <b> 11 that are set in a light-emitting disabled state are connected by a wire W. Further, the anode electrode of the semiconductor laser element LD4 and the cathode electrode of the semiconductor laser element LD6 are connected by a wire W1 in a state of jumping over the semiconductor laser element LD5.

  Thereby, the semiconductor laser elements LD1 to LD4, LD6 to LD11 are electrically connected in series, and the semiconductor laser element LD5 is electrically insulated from the semiconductor laser elements LD1 to LD4 and LD6 to LD11. Thus, if the cathode electrode of the semiconductor laser element LD1 electrically connected in series is connected to the negative electrode of the drive circuit (not shown) and the anode electrode of the semiconductor laser element LD11 is connected to the positive electrode of the drive circuit (not shown), the semiconductor Laser light is emitted from the semiconductor laser elements LD1 to LD4 and LD6 to LD11 excluding the laser element LD5. As described above, in this step, at least one of the semiconductor laser elements LD1 to LD11 is electrically insulated so as not to emit light. Note that, using the method described with reference to FIG. 3, at least one of the semiconductor laser elements LD <b> 1 to LD <b> 11 may be electrically short-circuited so as not to emit light.

  Finally, a step of mounting the condensing lens (F-axis condensing lens FL and S-axis condensing lens SL) and the optical fiber OF on the substrate B is performed (step S18). In addition, the condenser lens is fixed to the substrate B using, for example, an ultraviolet curable resin, similarly to the S-axis collimating lenses SAC1 to SAC11 and the double mirrors M1 to M11. Through the above series of steps, the semiconductor laser device 1 shown in FIG. 1 is manufactured.

  In the example shown in FIG. 5, it is determined whether or not at least one of the semiconductor laser elements LD1 to LD11 is in a light emission disabled state based on the measurement result of the optical monitor device OM (step S16). Based on this, wire bonding of the semiconductor laser elements LD1 to LD11 was performed (step S17). However, first, wire bonding of the semiconductor laser elements LD1 to LD11 is performed, and then it is determined whether or not at least one of the semiconductor laser elements LD1 to LD11 is in a light emission disabled state, and further wire is based on the determination result. Bonding may be performed.

  That is, first, all the semiconductor laser elements LD1 to LD11 are connected in series by wire bonding so that all the semiconductor laser elements LD1 to LD11 can emit light. Next, in a state where all the semiconductor laser elements LD1 to LD11 are caused to emit light, any one of the laser beams emitted from the semiconductor laser elements LD1 to LD11 is sequentially coupled using a shutter device (shutter jig). The light is incident on the system, is incident on the optical fiber OF, and the power of light emitted from the optical fiber OF is sequentially measured. In other words, the overall coupling efficiency of laser light to the optical fiber OF is measured.

  After the measurement is completed, it is determined whether or not at least one of the semiconductor laser elements LD1 to LD11 is in a light emission disabled state. Then, based on the determination result, the semiconductor laser element that makes the light emission impossible state by performing further wire bonding is electrically short-circuited. For example, the semiconductor laser element is short-circuited using any one of the directions described with reference to FIGS.

  As described above, in the method of manufacturing the semiconductor laser device 1 according to the present embodiment, the coupled optical system (F-axis collimating lenses FAC1 to FAC11, S-axis collimating lenses SAC1 to SAC11, 2) is emitted from the plurality of semiconductor laser elements LD1 to LD11. Fix and fix the coupling optical system so that the laser beam through at least a part of the continuous mirrors M1 to M11, the F-axis condenser lens FL, and the S-axis condenser lens SL) has a predetermined positional relationship. Yes. Whether or not at least one of the plurality of semiconductor laser elements LD1 to LD11 is made to emit light is measured by measuring the laser beam through at least a part of the fixed coupling optical system and referring to the measurement result. Judging. Thereafter, based on the determination result, at least one of the plurality of semiconductor laser elements LD1 to LD11 is electrically short-circuited or insulated by a conductive member so that light emission is disabled.

  For example, among the plurality of semiconductor laser elements LD1 to LD11, the semiconductor laser element having the worst coupling efficiency of the laser beam to the optical fiber OF, or the semiconductor laser element having the longest optical path length of the laser beam is set in a light emission disabled state. By making such a laser light emitting element in a state incapable of emitting light, overall coupling efficiency of the laser light to the optical fiber OF can be increased. As a result, wasteful laser light that is not coupled to the optical fiber OF can be reduced, and wasteful power consumption can be suppressed.

  In addition, for example, when the semiconductor laser device 1 is manufactured, if an optical appearance problem (for example, chipping or adhesion of foreign matter) that may cause significant deterioration in coupling efficiency occurs erroneously, the optical By preventing the laser light from passing through the component, the overall coupling efficiency can be prevented from deteriorating, and wasteful power consumption can be suppressed. If the overall coupling efficiency does not satisfy a predetermined reference value, the manufactured semiconductor laser device 1 should be defective, but does not emit laser light through the optical component. As a result, the overall coupling efficiency can be increased, so that the manufacturing yield can be improved.

[Second Embodiment]
8A and 8B are diagrams showing the configuration of the semiconductor laser device according to the second embodiment of the present invention, in which FIG. 8A is a plan view and FIG. 8B is a cross-sectional view taken along line AA in FIG. (C) is a cross-sectional view taken along line BB in (a). In FIG. 8, the same members as those shown in FIG. Further, FIG. 8 illustrates a configuration in which the semiconductor laser element LD5 is in a light emission disabled state, as in FIG.

  As shown in FIG. 8, the semiconductor laser device 2 of this embodiment includes a substrate B, a stepped mount MT (submount), (N + 1) semiconductor laser elements LD1 to LD11 (N = 10 in this embodiment), ( N + 1) F-axis collimating lenses FAC1 to FAC11, (N + 1) S-axis collimating lenses SAC1 to SAC11, (N + 1) mirrors RM1 to RM11, F-axis focusing lens FL, and S-axis focusing lens SL. Prepare. Similar to the semiconductor laser device 1 of the first embodiment, such a semiconductor laser device 2 collimates (converts into parallel light) the laser light emitted from the semiconductor laser elements LD1 to LD11, and then collects the light. Coupled to fiber OF.

  The stepped mount MT is a stepped member having a plurality of planes that are parallel to the ZX plane and have different heights (positions in the Y direction). As shown in FIG. 8B, each plane of the step-like mount MT is configured to advance (become higher) in the + Y direction side as it advances in the + X direction side. As shown in FIGS. 8A and 8B, semiconductor laser elements LD1 to LD11, F-axis collimating lenses FAC1 to FAC11, and S-axis collimating lenses SAC1 to SAC11 are mounted on a plurality of planes of the stepped mount MT. Placed.

  Here, the stepped mount MT is formed using a material having a high thermal conductivity in order to increase the heat radiation efficiency of the semiconductor laser elements LD1 to LD11 and a low thermal expansion coefficient in order to reduce the stress caused by the temperature change as much as possible. Is done. For example, similar to the substrate B, the stepped mount MT is suitably made of ceramics such as aluminum nitride (AlN) or metals such as molybdenum (Mo).

  The mirrors RM1 to RM11 emit laser beams (laser beams traveling in the + Z direction) emitted from the semiconductor laser elements LD1 to LD11 and passing through the F axis collimating lenses FAC1 to FAC11 and the S axis collimating lenses SAC1 to SAC11, respectively, by approximately −X. Reflect in the direction. The lengths of the mirrors RM1 to RM11 in the Y direction are set to be longer than the height of the laser light emitted from the semiconductor laser elements LD1 to LD11 (distance from the substrate B to the laser light).

  The mirrors RM1 to RM11 are surfaces parallel to the ZX plane and parallel to the laser light emitted from the semiconductor laser elements LD1 to LD11, and the optical axis of the laser light incident on the mirrors RM1 to RM11 and the mirror RM1. It arrange | positions so that the angle | corner with the reflective surface of -RM11 may become 45 degrees. Further, the mirrors RM1 to RM11 are arranged so that the distance (distance in the Z direction) from the semiconductor laser elements LD1 to LD11 is constant. For this reason, the optical axes of the laser beams emitted from the semiconductor laser elements LD1 to LD11 are aligned along the Y axis in a plane parallel to the ZX plane.

  As shown in FIG. 8C, the mirrors RM1 to RM11 are arranged with a slight inclination with respect to the Y axis. Further, the mirrors RM1 to RM11 are fixed on the substrate B by a fixture FX (for example, an adhesive or the like) in order to maintain an inclination angle. Further, the mirrors RM1 to RM11 are set so that the inclination angle with respect to the Y axis intersects at one point regardless of the optical axis of each laser beam regardless of the F-axis condenser lens FL. The laser beams reflected by the mirrors RM1 to RM11 are sequentially transmitted through the F-axis condenser lens FL and the S-axis condenser lens SL, and then combined at the incident end face of the optical fiber OF, as in the first embodiment. .

  The semiconductor laser device 2 of this embodiment differs from the semiconductor laser device 1 of the first embodiment in that the semiconductor laser elements LD1 to LD11 are mounted on the stepped mount MT, and the double mirrors M1 to M11. Instead, the only difference is that the mirrors RM1 to RM11 are provided. Such a semiconductor laser device 2 is manufactured by a method similar to the manufacturing method described in the first embodiment. For this reason, the description of the manufacturing method of the semiconductor laser device 2 is omitted.

  As described above, also in the semiconductor laser device 2 according to the present embodiment, at least one of the plurality of semiconductor laser elements LD1 to LD11 is electrically insulated (or short-circuited) by the wire W1 (or the conductive sheet ST or the wire W2). ) And cannot emit light. For this reason, the overall coupling efficiency of the laser beam to the optical fiber OF can be increased, and wasteful power consumption can be suppressed. Since the semiconductor laser device 2 according to the present embodiment is manufactured by the same method as that of the first embodiment, the manufacturing yield can be improved.

[Third Embodiment]
FIG. 9 is a cross-sectional view of a semiconductor laser device according to the third embodiment of the present invention, and FIG. 10 is a front view of the semiconductor laser device according to the third embodiment of the present invention. FIG. 9 is a cross-sectional view in a plane parallel to the YZ plane. 9 and 10, the same members as those shown in FIG. 1 are denoted by the same reference numerals.

  The semiconductor laser device 3 of the present embodiment has substantially the same basic configuration as the semiconductor laser device 1 described above. Specifically, the substrate B, (N + 1) (N = 10 in this embodiment) semiconductor laser elements LD1 to LD11, (N + 1) F-axis collimating lenses FAC1 to FAC11, and (N + 1) S-axis collimators. Lenses SAC1 to SAC11, (N + 1) mirrors SM1 to SM11, an F-axis condenser lens FL, and an S-axis condenser lens SL are provided. Similar to the semiconductor laser device 1 of the first embodiment, such a semiconductor laser device 3 collimates the laser light emitted from the semiconductor laser elements LD1 to LD11 (converts it into parallel light) and then condenses the light. Coupled to fiber OF.

  Although not shown in FIGS. 9 and 10, the semiconductor laser elements LD1 to LD11 provided in the semiconductor laser device 3 of the present embodiment are the semiconductor laser elements LD1 to LD11 provided in the semiconductor laser device 1 of the first embodiment. It is assumed that the same connection is made. Specifically, the semiconductor laser elements LD1 to LD4, LD6 to LD11 are electrically connected in series, and the semiconductor laser element LD5 is electrically insulated from the semiconductor laser elements LD1 to LD4 and LD6 to LD11. . Thereby, also in the present embodiment, it is assumed that the semiconductor laser element LD5 is in a state incapable of emitting light.

  A semiconductor laser element LDi (i is an integer satisfying 1 ≦ i ≦ N) shown in FIG. 9 indicates any one of the semiconductor laser elements LD1 to LD11, and the S-axis collimating lens SACi is an S-axis collimating lens SAC1 to SAC1. One of the SACs 11 is shown, and the mirror SMi is one of the mirrors SM1 to SM11. In FIG. 9, the F-axis collimating lenses FAC1 to FAC11 are not shown. As shown in FIG. 9, the semiconductor laser element LDi, the S-axis collimating lens SACi, and the mirror SMi are mounted on the submount SB fixed on the substrate B by soldering. Further, the semiconductor laser element LDi and the S-axis collimating lens SACi are fixed on the laser mount LM fixed on the submount SB.

  As shown in FIG. 9, the mirror SMi has a reflection surface P1 that reflects the laser light emitted from the semiconductor laser element LDi and a fixed surface P2 that is fixed to the submount SB. In the mirror SMi, the angle formed by the reflecting surface P1 and the fixed surface P2 is an acute angle. For this reason, by arranging the mirror SMi so that the fixed surface P2 is parallel to the surface of the submount SB, the reflecting surface P1 is inclined with respect to the normal of the surface of the submount SB. The

  The mirror SMi is a glass body having a reflective surface P1 formed on the surface by a reflective film made of a dielectric multilayer film, for example, and the fixed surface P2 is fixed to the surface of the submount SB with an adhesive. Such a mirror SMi is obtained, for example, by forming a reflective film after obliquely shaving the surface on the side where the fixed surface P2 is formed in a rectangular parallelepiped glass body. The reflective surface P1 may be formed of a metal film, and the mirror SMi may be formed of a prism.

  The light emitted from the semiconductor laser element LDi is reflected in the direction in which the mirrors SMi are arranged as viewed from the F-axis (fast axis) direction (Y-axis direction). Further, the reflection surface P1 of the mirror SMi is inclined as described above, and incident laser light can be reflected in an oblique direction with respect to the surface of the submount SB. For this reason, as shown in FIG. 10, the light reflected by each mirror SMi propagates in the space opposite to the submount SB of the other mirror SMi disposed adjacent to the F-axis condenser lens FL side. . In this way, the mirrors SM1 to SM11 can reflect the laser beams emitted from the semiconductor laser elements LD1 to LD11 so that they are aligned in the F-axis direction.

  Further, the mirrors SM1 to SM11 reflect the laser beams emitted from the semiconductor laser elements LD1 to LD11 so that the propagation directions are parallel to each other. That is, when the distances between the semiconductor laser elements LD1 to LD11 are equal and the laser beams emitted from the semiconductor laser elements LD1 to LD11 are parallel to each other, the reflection surface P1 of the mirrors SM1 to SM11 is relative to the surface of the submount SB. Are generally at the same angle. The laser light reflected by each of the mirrors SM1 to SM11 sequentially passes through the F-axis condenser lens FL and the S-axis condenser lens SL, and then is coupled at the incident end face of the optical fiber OF.

  The semiconductor laser device 3 of the present embodiment is different from the semiconductor laser device 1 of the first embodiment in that mirrors SM1 to SM11 are provided instead of the double mirrors M1 to M11, and the laser reflected in an oblique direction by the mirrors SM1 to SM11. The only difference is that the light is coupled to one optical fiber OF. Such a semiconductor laser device 3 is manufactured by a method similar to the manufacturing method described in the first embodiment. For this reason, the description of the manufacturing method of the semiconductor laser device 3 is omitted.

  As described above, also in the semiconductor laser device 3 according to the present embodiment, at least one of the plurality of semiconductor laser elements LD1 to LD11 is electrically insulated (or short-circuited) by the wire W1 (or the conductive sheet ST or the wire W2). ) And cannot emit light. For this reason, the overall coupling efficiency of the laser beam to the optical fiber OF can be increased, and wasteful power consumption can be suppressed. Since the semiconductor laser device 2 according to the present embodiment is manufactured by the same method as that of the first embodiment, the manufacturing yield can be improved.

  As mentioned above, although embodiment of this invention was described, this invention is not restrict | limited to the said embodiment, It can change freely within the scope of the present invention. For example, in the above embodiment, 11 semiconductor laser elements LD1 to LD11, 11 collimating lenses (F-axis collimating lenses FAC1 to FAC11, S-axis collimating lenses SAC1 to SAC11), and 11 double mirrors M1 to M11. The semiconductor laser device including the mirrors RM1 to RM11 or the mirrors SM1 to SM11 has been described as an example. However, the number of semiconductor laser elements, collimating lenses, and reflection optical systems is arbitrary.

DESCRIPTION OF SYMBOLS 1-3 ... Semiconductor laser apparatus, 12, 13 ... Electrode chip, FAC1-FAC11 ... F-axis collimating lens, FL ... F-axis condensing lens, LD1-LD11 ... Semiconductor laser element, M1-M11 ... Double mirror, OF ... Optical fiber, SAC1 to SAC11 ... S axis collimating lens, SL ... S axis condensing lens, ST ... conductive sheet, W, W1, W2 ... wire

Claims (10)

In a semiconductor laser device comprising: a plurality of semiconductor laser elements; and a coupling optical system that couples laser light emitted from the plurality of semiconductor laser elements to one optical fiber.
At least one of the plurality of semiconductor laser elements is a semiconductor laser device in which light emission is disabled by being electrically short-circuited or insulated by a conductive member and cannot emit light.   2. The semiconductor laser device according to claim 1, wherein the semiconductor laser element that is in a state in which light emission is disabled has the worst coupling efficiency of laser light to the optical fiber when light is emitted from the plurality of semiconductor laser elements. . The plurality of semiconductor laser elements are arranged adjacent to each other,
The semiconductor laser element in the non-light emitting state is configured such that a positive electrode of the semiconductor laser element adjacent on one side and a negative electrode of the semiconductor laser element adjacent on the other side are connected by a conductive wiring. Electrically shorted or insulated,
The semiconductor laser device according to claim 1 or 2. The plurality of semiconductor laser elements are arranged adjacent to each other,
The semiconductor laser element in the non-light emitting state is electrically short-circuited by connecting a positive electrode and a negative electrode by a conductive wiring or by covering a positive electrode and a negative electrode with a conductive sheet. Yes,
The semiconductor laser device according to claim 1 or 2.   5. The semiconductor laser device according to claim 3, wherein the plurality of semiconductor laser elements are electrically connected in series with a positive electrode and a negative electrode of the adjacent semiconductor laser elements connected by wiring. 6. A first step of disposing and fixing a plurality of semiconductor laser elements and at least a part of a coupling optical system for coupling laser beams emitted from the plurality of semiconductor laser elements to one optical fiber on a substrate; ,
A second step of measuring laser light via at least a part of the fixed coupling optical system;
Referring to the measurement result of the second step, a third step of determining whether or not to enter a light emission disabled state in which at least one of the plurality of semiconductor laser elements cannot emit light;
Of manufacturing a semiconductor laser device.   In the second step, in a state where all of the plurality of semiconductor laser elements electrically connected in series are made to emit light, only one of the laser beams emitted from the plurality of semiconductor laser elements is sequentially combined. The method for manufacturing a semiconductor laser device according to claim 6, wherein the method is a step of measuring a laser beam incident on an optical system and passing through at least a part of the coupling optical system.   7. The fourth step further includes a fourth step in which at least one of the plurality of semiconductor laser elements is electrically short-circuited or insulated by a conductive member based on the determination result of the third step so as not to emit light. Alternatively, a method for manufacturing a semiconductor laser device according to claim 7.   In the fourth step, among the semiconductor laser elements arranged adjacent to each other, the positive electrode of the semiconductor laser element that is adjacent on one side of the semiconductor laser element that is not allowed to emit light is adjacent to the positive electrode of the semiconductor laser element that is adjacent to the other side. 9. The method of manufacturing a semiconductor laser device according to claim 8, wherein the semiconductor laser device is a step of electrically short-circuiting or insulating by connecting the negative electrode of the semiconductor laser element with a conductive wiring.   In the fourth step, among the semiconductor laser elements arranged adjacent to each other, a positive electrode and a negative electrode of the semiconductor laser element that is in a non-light-emitting state are connected by a conductive wiring, or the positive electrode and the The method of manufacturing a semiconductor laser device according to claim 8, wherein the semiconductor laser device is a step of electrically short-circuiting the negative electrode with a conductive sheet.

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