WO2023027096A1

WO2023027096A1 - Optical module and optical module manufacturing method

Info

Publication number: WO2023027096A1
Application number: PCT/JP2022/031822
Authority: WO
Inventors: 大輔森田; 友博京藤; 正人河▲崎▼
Original assignee: 三菱電機株式会社
Priority date: 2021-08-26
Filing date: 2022-08-24
Publication date: 2023-03-02
Also published as: JPWO2023027096A1

Abstract

This optical module (1C) comprises: a multi-emitter semiconductor laser bar (2) equipped with a plurality of light-emitting points; a lens unit (25) having a collimating lens array (4) that causes a plurality of beams outputted from the multi-emitter semiconductor laser bar (2) to be parallel to one another; and a holding member (27) for holding the collimating lens array (4). The orientation of a curve of the collimating lens array (4) in a flat plane which includes the collimating lens array (4) and which is orthogonal to a beam propagation direction is identical with the orientation of a curve of a line connecting the plurality of light-emitting points in a flat plane which includes the plurality of light-emitting points and which is orthogonal to the beam propagation direction. The holding member (27) supports the collimating lens array (4) from one side of a first direction orthogonal to the beam propagation direction and to the orientation of the curve of the collimating lens array (4).

Description

Optical module and method for manufacturing optical module

The present disclosure relates to an optical module that outputs laser light and a method for manufacturing the optical module.

Conventionally, an optical module that outputs a laser beam has been used to process a workpiece. For example, an optical module has been proposed that has a multi-emitter semiconductor laser bar including a plurality of light emitting points and a collimator lens array for collimating the plurality of beams output by the multi-emitter semiconductor laser bar. Conventionally, there has also been proposed a lens component having a plate-like portion, a lens portion provided on the lower surface of the plate-like portion, and a pair of rib portions extending along the plate-like portion with the plate-like portion therebetween (for example, See Patent Document 1).

Japanese Patent No. 5899925

As described above, an optical module is known that has a multi-emitter semiconductor laser bar including multiple light-emitting points and a collimating lens array for collimating the multiple beams output by the multi-emitter semiconductor laser bar. In this optical module, if the direction of warp of the line connecting the plurality of light emitting points is different from the direction of warp of the collimating lens array, the plurality of beams output from the multi-emitter semiconductor laser bar will not travel straight. If the beams do not travel straight, the amount of laser light that can be used for processing is reduced. When the amount of laser light decreases, it becomes difficult to process the workpiece.

Patent Document 1 discloses a technique for suppressing deformation on the lens side. and the warp direction of the collimating lens array are different. In other words, in the conventional technique, a loss in propagation of the laser light output from the optical module may occur.

The present disclosure has been made in view of the above, and aims to obtain an optical module that suppresses the occurrence of propagation loss of output laser light.

In order to solve the above-described problems and achieve the object, an optical module according to the present disclosure includes a multi-emitter semiconductor laser bar having a plurality of light emitting points, and a multi-emitter semiconductor laser bar for collimating a plurality of beams output from the multi-emitter semiconductor laser bar. a lens unit having a collimating lens array of . The lens unit further has a holding member that holds the collimating lens array. The direction of warp of the collimator lens array on a plane that is orthogonal to the propagation direction of the plurality of beams and contains the collimator lens array is determined by a plurality of warps on a plane that is orthogonal to the propagation direction and contains the plurality of light emitting points. It is the same as the warp direction of the line connecting the light emitting points. The holding member supports the collimating lens array from one side in a first direction perpendicular to the warp direction and propagation direction of the collimating lens array.

The optical module according to the present disclosure has the effect of being able to suppress the occurrence of propagation loss of output laser light.

FIG. 2 schematically shows a side surface of the optical module according to the first embodiment; 1 is a diagram schematically showing a plane of an optical module according to Embodiment 1; FIG. FIG. 2 schematically shows the front surface of the optical module according to the first embodiment; 4 is a flow chart showing an example of the procedure of the method for manufacturing the optical module according to the first embodiment; 4A and 4B are diagrams for explaining the method for manufacturing the optical module according to the first embodiment; FIG. 4 is a diagram schematically showing a side surface of an optical module according to Embodiment 2; FIG. 1 is a first diagram for explaining effects obtained by the optical module according to the second embodiment; FIG. 2 is a second diagram for explaining effects obtained by the optical module according to the second embodiment; FIG. 11 is a diagram schematically showing a side surface of an optical module according to Embodiment 3; FIG. 1 is a first diagram for explaining effects obtained by the optical module according to the third embodiment; FIG. 2 is a second diagram for explaining effects obtained by the optical module according to the third embodiment; FIG. 11 is a diagram schematically showing a side surface of an optical module according to Embodiment 4; FIG. 12 is a diagram schematically showing a plane of an optical module according to Embodiment 4; FIG. 11 is a diagram schematically showing the front of an optical module according to a fourth embodiment; FIG. 11 is a diagram schematically showing a side surface of an optical module according to Embodiment 5;

The optical module and the method for manufacturing the optical module according to the embodiment will be described in detail below with reference to the drawings.

Embodiment 1.
FIG. 1 is a diagram schematically showing a side surface of an optical module 1 according to Embodiment 1. FIG. In the drawings of this application, each of "X,""Y," and "Z" designates an axis, and each of the X, Y, and Z axes are orthogonal to the other two axes. FIG. 1 schematically shows a side surface of an optical module 1 parallel to a plane containing the Y-axis and Z-axis. FIG. 2 is a schematic plan view of the optical module 1 according to the first embodiment. More specifically, FIG. 2 schematically shows the plane of the optical module 1 parallel to the plane containing the X-axis and Z-axis. The positive direction of the Z-axis is the direction in which the beam of laser light propagates.

The optical module 1 has a multi-emitter semiconductor laser bar 2 containing multiple light emitting points. The multi-emitter semiconductor laser bar 2 is an element that outputs laser light. For example, the semiconductor that mainly contributes to the laser light output of the multi-emitter semiconductor laser bar 2 is gallium arsenide. For example, the oscillation output of the multi-emitter semiconductor laser bar 2 is several hundred watts or more. As described above, the multi-emitter semiconductor laser bar 2 has a plurality of light emitting points and thus outputs a plurality of beams. Details of the plurality of light emitting points will be described later.

The optical module 1 further comprises a cooling structure 3 on which the multi-emitter semiconductor laser bar 2 is mounted to dissipate the heat generated in the multi-emitter semiconductor laser bar 2 . For example, the cooling structure 3 is formed with water channels, and the cooling structure 3 dissipates the heat generated in the multi-emitter semiconductor laser bar 2 by the water flowing through the channels.

The optical module 1 further has a collimating lens array 4 for collimating the multiple beams output by the multi-emitter semiconductor laser bar 2 . The collimator lens array 4 is provided in front of the multi-emitter semiconductor laser bar 2 in the direction in which the multiple beams output by the multi-emitter semiconductor laser bar 2 propagate. The longitudinal direction of the collimator lens array 4 is the direction of the X-axis. For example, in the collimator lens array 4, the shape in the positive direction of the X-axis and the shape in the negative direction of the X-axis are symmetrical with respect to the center in the longitudinal direction. The optical module 1 further has a holding member 5 for holding the collimator lens array 4 . The material forming the holding member 5 and the material forming the collimating lens array 4 are preferably the same.

The optical module 1 further includes a first joint member 6 joining the collimating lens array 4 and the holding member 5 together, and a second joint member 7 joining the cooling structure 3 and the holding member 5 together. have. It is preferable that the heat resistance strength of the first joint member 6 is greater than the heat resistance strength of the second joint member 7 . The second joining member 7 is preferably made of an ultraviolet curable resin adhesive. 1 and 2 do not show a power supply mechanism for supplying current to the multi-emitter semiconductor laser bar 2. FIG. The center of the multi-emitter semiconductor laser bar 2 on a plane parallel to the plane containing the X-axis and Y-axis (hereinafter sometimes referred to as the XY plane) and the center of the collimating lens array 4 on the plane parallel to the XY plane The connecting lines are parallel to the Z-axis.

FIG. 3 is a diagram schematically showing the front of the optical module 1 according to Embodiment 1. FIG. The front side is the side from which the multi-emitter semiconductor laser bar 2 outputs a plurality of beams. More specifically, the front plane is a plane parallel to the plane containing the X and Y axes. As can be understood from FIG. 1, when viewed from the positive side of the Z-axis toward the negative side of the Z-axis, the multiple light-emitting points 2a of the multi-emitter semiconductor laser bar 2 are collimated by the collimating lens array 4. hide. However, FIG. 3 shows a plurality of light emitting points 2a that the multi-emitter semiconductor laser bar 2 has. A plurality of light emitting points 2a in FIG. 3 are shown to explain that the multi-emitter semiconductor laser bar 2 has a plurality of light emitting points 2a.

FIG. 3 shows an arc 4a that indicates the warp of the collimating lens array 4. Arc 4a is indicated by a dashed line. The warp of the collimator lens array 4 is the warp of the collimator lens array 4 on a plane that is perpendicular to the propagation direction of the multiple beams output from the multi-emitter semiconductor laser bar 2 and includes the collimator lens array 4 . As indicated by arc 4a, the direction of warp of collimating lens array 4 in FIG. 3 is the direction of protruding to the negative side of the Y-axis.

In the optical module 1, the direction of the warp of the collimating lens array 4 is a plane orthogonal to the propagation direction of the plurality of beams output from the multi-emitter semiconductor laser bar 2 and a plurality of light emitting points on a plane including the plurality of light emitting points 2a. It is the same as the warp direction of the line connecting 2a.

FIG. 4 is a flow chart showing an example of the procedure of the method for manufacturing the optical module 1 according to the first embodiment. When manufacturing the optical module 1, first, a line connecting a plurality of light emitting points 2a on a plane orthogonal to the propagation direction of a plurality of beams output from the multi-emitter semiconductor laser bar 2 and including the plurality of light emitting points 2a. The direction of warpage is measured (step S1). That is, in step S1, the warp direction of the line connecting the plurality of light emitting points 2a in the Y-axis direction is measured. In FIG. 4, step S1 is described as "measure the direction of warpage of the multi-emitter semiconductor laser bar".

Next, the direction of warp of the collimating lens array 4 is measured on a plane that is orthogonal to the propagation direction of the beams made parallel by the collimating lens array 4 and that includes the collimating lens array 4 (step S2). That is, in step S2, the warp direction of the collimating lens array 4 in the Y-axis direction is measured. Next, the measured warp direction of the collimating lens array 4 is made the same as the measured warp direction of the line connecting the plurality of light emitting points 2a (step S3). In FIG. 4, step S3 is described as "making the direction of warp of the collimating lens array the same as the direction of warp of the multi-emitter semiconductor laser bar". Next, the holding member 5 to which the collimating lens array 4 is bonded by the first bonding member 6 is bonded to the cooling structure 3 by the second bonding member 7 (step S4). Either step S1 or step S2 may be executed first.

Next, the operation of step S3 in FIG. 4 will be further described. That is, the operation for making the warp direction of the collimator lens array 4 the same as the warp direction of the line connecting the plurality of light emitting points 2a will be further described. FIG. 5 is a diagram for explaining the method of manufacturing the optical module 1 according to the first embodiment. As shown on the left side of arrows A and B in FIG. 5, it is assumed that the collimator lens array 4 is warped in the direction of protruding toward the positive side of the Y axis.

As shown on the right side of the arrow A, when the direction of the warp of the line 2b connecting the plurality of light emitting points 2a projects toward the negative side of the Y axis, as shown on the right side of the arrow A1, Secondly, the collimating lens array 4 is rotated halfway around its center axis parallel to the Z-axis, so that the direction of the warp of the collimating lens array 4 protrudes to the negative side of the Y-axis. As a result, the warp direction of the collimating lens array 4 is made the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a. A line 2b connecting the plurality of light emitting points 2a is indicated by a solid line.

As shown on the right side of the arrow B, when the direction of the warp of the line 2b connecting the plurality of light emitting points 2a projects toward the positive side of the Y axis, as shown on the right side of the arrow B1 First, the collimating lens array 4 is not rotated around the central axis parallel to the Z-axis of the collimating lens array 4. - 特許庁As a result, the warp direction of the collimating lens array 4 is made the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a.

As described above, in the optical module 1 according to Embodiment 1, the warp direction of the collimating lens array 4 is the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. Therefore, it is suppressed that a plurality of beams output from the multi-emitter semiconductor laser bar 2 do not travel straight. Therefore, the optical module 1 can suppress the occurrence of propagation loss of the output laser light. In other words, the optical module 1 can efficiently propagate the output laser light.

In Embodiment 1, the optical module 1 is manufactured with the warp direction of the collimator lens array 4 being the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a. Therefore, according to the method for manufacturing an optical module according to the first embodiment, it is possible to manufacture the optical module 1 that suppresses the occurrence of propagation loss of the output laser light.

Embodiment 2.
FIG. 6 is a diagram schematically showing a side surface of the optical module 1A according to the second embodiment. The optical module 1A has all the components of the optical module 1 according to the first embodiment. The optical module 1A has components that the optical module 1 does not have. In Embodiment 2, differences from Embodiment 1 will be mainly described.

The optical module 1A further has an optical element 8a that the optical module 1 does not have. The optical element 8a is provided in front of the collimator lens array 4 in the direction in which the multiple beams output by the multi-emitter semiconductor laser bar 2 propagate. For example, optical element 8a is a microlens array, a beam transfer system or a prism. The optical module 1A further has a joining member 9a joining the optical element 8a and the holding member 5 together. For example, the joint member 9 a is made of the same material as the first joint member 6 .

In the second embodiment, the warp direction of the optical element 8a on the plane orthogonal to the propagation direction of the plurality of beams output from the multi-emitter semiconductor laser bar 2 is the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a. are the same. When manufacturing the optical module 1A, for the optical element 8a, similarly to the collimating lens array 4, the direction of warp on a plane orthogonal to the propagation direction of the passing beam is measured. That is, the warpage of the optical element 8a in the Y-axis direction is measured. Next, the warp direction of the measured optical element 8a is set to be the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a. Note that the process of measuring the direction of warp of the optical element 8a, the above-described steps S1 and S2 may be performed in any order. A line connecting the center of the multi-emitter semiconductor laser bar 2 on a plane parallel to the XY plane, the center of the collimating lens array 4 on a plane parallel to the XY plane, and the center of the optical element 8a on a plane parallel to the XY plane. is parallel to the Z-axis.

FIG. 7 is a first diagram for explaining effects obtained by the optical module 1A according to the second embodiment. In FIG. 7, the warp direction of the collimating lens array 4 is different from the warp direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. In FIG. In addition, the warp direction of the optical element 8 a is different from the warp direction of the collimator lens array 4 .

In the situation shown in FIG. 7, among the multiple beams output from the multi-emitter semiconductor laser bar 2, there are beams 10 that go straight, but there are also beams 20 that do not go straight. A non-linear beam 20 is generated at each of the collimating lens array 4 and the optical element 8a. The generation of the beam 20 that does not travel straight means that the laser light output from the multi-emitter semiconductor laser bar 2 does not propagate efficiently.

FIG. 8 is a second diagram for explaining the effects obtained by the optical module 1A according to the second embodiment. In FIG. 8, the warp direction of the collimating lens array 4 is the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. In FIG. The warping direction of the optical element 8a is also the same as the warping direction of the line 2b connecting the plurality of light emitting points 2a.

That is, FIG. 8 shows the state of propagation of a plurality of beams in the optical module 1A according to the second embodiment. As described above, since the direction of warp of the collimating lens array 4 and the direction of warp of the optical element 8a are the same as the direction of warp of the line 2b connecting the plurality of light emitting points 2a, generation of the beam 20 that does not travel straight is suppressed. A relatively large number of beams out of the plurality of beams output from the multi-emitter semiconductor laser bar 2 become beams 10 that travel straight. Therefore, the optical module 1A can suppress the occurrence of propagation loss of the output laser light.

As described above, in the optical module 1A according to the second embodiment, the direction of warp of the collimating lens array 4 and the direction of warp of the optical element 8a correspond to the direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. It is the same as the warp direction. Therefore, it is suppressed that a plurality of beams output from the multi-emitter semiconductor laser bar 2 do not travel straight. Therefore, the optical module 1A can suppress the occurrence of propagation loss of the output laser light. In other words, the optical module 1A can efficiently propagate the output laser light.

In Embodiment 2, the optical module 1A is manufactured by setting the warp directions of the collimating lens array 4 and the warp directions of the optical elements 8a to be the same as the warp directions of the lines 2b connecting the plurality of light emitting points 2a. Therefore, according to the optical module manufacturing method according to the second embodiment, it is possible to manufacture the optical module 1A that suppresses the occurrence of propagation loss of the output laser light.

Embodiment 3.
FIG. 9 is a diagram schematically showing a side surface of the optical module 1B according to the third embodiment. The optical module 1B has all the components of the optical module 1 according to the first embodiment. The optical module 1B has components that the optical module 1 does not have. In Embodiment 3, differences from Embodiment 1 will be mainly described.

The optical module 1B further has optical elements 8a, . . . , 8n that the optical module 1 does not have. The optical elements 8a, . For example, each of the optical elements 8a, . . . , 8n has a different function than the other optical elements. For example, each of the optical elements 8a, . . . , 8n is a microlens array, a beam transfer system or a prism. The optical module 1B further includes joining members 9a, . . . , 9n joining the optical elements 8a, . For example, each of the joint members 9a, . . . , 9n is made of the same material as the first joint member 6.

In Embodiment 3, for each of the optical elements 8a, . It is the same as the warp direction of the connecting line 2b.

When manufacturing the optical module 1B, for each of the optical elements 8a, . That is, the warpage of each of the optical elements 8a, . . . , 8n in the Y-axis direction is measured. Next, the direction of warpage of each of the measured optical elements 8a, .

. . , 8n, the process of measuring the warp direction of the line connecting the plurality of light emitting points 2a (step S1), and the collimator lens array 4. The process of measuring the direction of warpage (step S2) may be performed in any order.

In the optical module 1B, the optical elements 8a, . . . , 8n are arranged in the order of the optical elements 8a, . It is The center of the multi-emitter semiconductor laser bar 2 on a plane parallel to the XY plane, the center of the collimator lens array 4 on a plane parallel to the XY plane, and the optical elements 8a, . is parallel to the Z-axis.

FIG. 10 is a first diagram for explaining effects obtained by the optical module 1B according to the third embodiment. In FIG. 10, the warp direction of the collimator lens array 4 is different from the warp direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. In FIG. In addition, the direction of warpage of each of the optical elements 8a, . It is different from the warp direction of the element. That is, in the case of the optical elements 8b, . different.

In the situation shown in FIG. 10, among the plurality of beams output from the multi-emitter semiconductor laser bar 2, there are beams 10 that go straight, but there are also beams 20 that do not go straight. A non-linear beam 20 is generated at each of the collimating lens array 4 and the optical elements 8a, . . . , 8n. The generation of the beam 20 that does not travel straight means that the laser light output from the multi-emitter semiconductor laser bar 2 does not propagate efficiently.

FIG. 11 is a second diagram for explaining the effects obtained by the optical module 1B according to the third embodiment. In FIG. 11, the warp direction of the collimating lens array 4 is the same as the warp direction of the line 2b connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. In FIG. The direction of warp of each of the optical elements 8a, .

That is, FIG. 11 shows the state of propagation of a plurality of beams in the optical module 1B according to the third embodiment. As described above, the direction of warp of the collimating lens array 4 and the direction of warp of each of the optical elements 8a, . Generation of the beams 20 is suppressed, and a relatively large number of beams out of the plurality of beams output from the multi-emitter semiconductor laser bar 2 become the straight beams 10 . Therefore, the optical module 1B can suppress the occurrence of propagation loss of the output laser light.

As described above, in the optical module 1B according to the third embodiment, the direction of warp of the collimator lens array 4 and the direction of warp of each of the optical elements 8a, . It is the same as the warp direction of the line 2b connecting the light emitting points 2a. Therefore, it is suppressed that a plurality of beams output from the multi-emitter semiconductor laser bar 2 do not go straight. Therefore, the optical module 1B can suppress the occurrence of propagation loss of the output laser light. In other words, the optical module 1B can efficiently propagate the output laser light.

In the third embodiment, the direction of warp of the collimating lens array 4 and the direction of warp of each of the optical elements 8a, . An optical module 1B is manufactured. Therefore, according to the optical module manufacturing method according to the third embodiment, it is possible to manufacture the optical module 1B that suppresses the occurrence of propagation loss of the output laser light.

Embodiment 4.
FIG. 12 is a diagram schematically showing a side surface of an optical module 1C according to the fourth embodiment. FIG. 12 schematically shows a side surface of the optical module 1C parallel to a plane including the Y-axis and Z-axis (hereinafter referred to as YZ plane). FIG. 13 is a schematic plan view of an optical module 1C according to the fourth embodiment. FIG. 13 schematically shows a plane of the optical module 1C parallel to a plane containing the X-axis and the Z-axis (hereinafter referred to as the XZ plane). FIG. 14 is a diagram schematically showing the front of an optical module 1C according to the fourth embodiment. FIG. 14 schematically shows the front of the optical module 1C parallel to the XY plane, which is a plane containing the X axis and the Y axis.

The front face of the optical module 1C is the side from which the multi-emitter semiconductor laser bar 2 outputs a plurality of beams. More specifically, the front is the XY plane parallel to the plane containing the X and Y axes. 12 to 14 do not show a power supply mechanism for supplying current to the multi-emitter semiconductor laser bar 2. FIG.

In the fourth embodiment, as in the first to third embodiments, the center of the multi-emitter semiconductor laser bar 2 on a plane parallel to the XY plane is connected to the center of the collimator lens array 4 on a plane parallel to the XY plane. The lines are parallel to the Z-axis.

The optical module 1C has the multi-emitter semiconductor laser bar 2 and the cooling structure 3 described in the first to third embodiments. Each of the multi-emitter semiconductor laser bar 2 and the cooling structure 3 is a rectangular parallelepiped having a surface parallel to the XY plane, a surface parallel to the YZ plane, and a surface parallel to the XZ plane.

The optical module 1C further has a lens unit 25 including a collimating lens array 4 for collimating the multiple beams output by the multi-emitter semiconductor laser bar 2. The collimator lens array 4 is provided in front of the multi-emitter semiconductor laser bar 2 in the direction in which the multiple beams output by the multi-emitter semiconductor laser bar 2 propagate.

As can be understood from FIG. 12, when viewed from the positive side of the Z-axis toward the negative side of the Z-axis, the multiple light-emitting points 2a of the multi-emitter semiconductor laser bar 2 are formed by the collimating lens array 4. hide. However, FIG. 14 shows a plurality of light emitting points 2a that the multi-emitter semiconductor laser bar 2 has. A plurality of light emitting points 2a in FIG. 14 are shown for explaining that the multi-emitter semiconductor laser bar 2 has a plurality of light emitting points 2a.

The collimating lens array 4 is a cuboid having a surface parallel to the XY plane, a surface parallel to the YZ plane, and a surface parallel to the XZ plane. The front surface of the collimating lens array 4 is a plane parallel to the XY plane facing the negative direction of the Z axis. The back surface of the collimating lens array 4 is a plane parallel to the XY plane facing the positive direction of the Z axis. A plurality of beams output by the multi-emitter semiconductor laser bar 2 enter from the front surface of the collimating lens array 4 and emerge from the back surface. The longitudinal direction of the collimator lens array 4 is the direction of the X-axis. For example, in the collimator lens array 4, the shape in the positive direction of the X-axis and the shape in the negative direction of the X-axis are symmetrical with respect to the center in the longitudinal direction.

In the optical module 1C, a multi-emitter semiconductor laser bar 2 and a collimator lens array 4 are arranged at the same positions as in the optical module 1. That is, the positional relationship of the collimating lens array 4 with respect to the multi-emitter semiconductor laser bar 2 is the same between the optical module 1 and the optical module 1C.

The lens unit 25 has a holding member 27 for holding the collimating lens array 4. The optical module 1</b>C further has a third joint member 11 joining the cooling structure 3 and the holding member 27 of the lens unit 25 . As shown in FIG. 14, the holding member 27 supports the collimating lens array 4 from one side in the direction orthogonal to the direction of warp of the collimating lens array 4, and supports a plurality of beams collimated by the collimating lens array 4. let it pass. That is, the collimator lens array 4 is a cantilever beam. In other words, the optical module 1C supports the collimator lens array 4 with a cantilever structure.

Thus, the holding member 27 supports the collimating lens array 4 from one side in the first direction perpendicular to the direction of warp of the collimating lens array 4 and the propagation direction of the plurality of beams. The warping direction of the collimating lens array 4 is parallel to the Y-axis. The propagation directions of the multiple beams are parallel to the Z-axis. The first direction is a direction parallel to the X-axis.

The holding member 27 extends in the Z-axis direction. The shape of the holding member 27 is, for example, a columnar shape such as a square column extending in the Z-axis direction. Below, the case where the shape of the holding member 27 is a quadrangular prism extending in the Z-axis direction will be described. The holding member 27 is a cuboid having a surface parallel to the XY plane, a surface parallel to the YZ plane, and a surface parallel to the XZ plane.

A part of the bottom surface of the holding member 27 is joined to the upper surface of the cooling structure 3 by the third joining member 11 . That is, the holding member 27 has its bottom surface joined to the top surface of the cooling structure 3 and extends from the cooling structure 3 in a direction parallel to the Z-axis, which is the propagation direction of the plurality of beams. Both the bottom surface of the holding member 27 and the top surface of the cooling structure 3 are parallel to the XZ plane.

It should be noted that the holding member 27 may be joined to one of the side surfaces parallel to the YZ plane of the multi-emitter semiconductor laser bar 2 by a fourth joining member (not shown). In other words, the holding member 27 may be joined to one end face of the multi-emitter semiconductor laser bar 2 in the X-axis direction by a fourth joining member.

In addition, the holding member 27 is joined by a fifth joining member 13 to one of the side surfaces of the collimating lens array 4 that are parallel to the YZ plane. In other words, the holding member 27 is joined to one end surface of the collimating lens array 4 in the X-axis direction by the fifth joining member 13 .

The side surface parallel to the YZ plane of the holding member 27 is the first surface, and the bottom surface parallel to the XZ plane is the second surface. The side surface of the multi-emitter semiconductor laser bar 2 parallel to the YZ plane is the third surface, and the side surface of the collimating lens array 4 parallel to the YZ plane is the fourth surface.

It should be noted that the holding member 27 may be joined to either of the two side surfaces of the multi-emitter semiconductor laser bar 2 parallel to the YZ plane. For example, the holding member 27 may be joined to the side facing the negative direction of the X-axis out of the two side faces parallel to the YZ plane of the multi-emitter semiconductor laser bar 2, or the side facing the positive direction of the X-axis. may be joined to. Note that the holding member 27 may be joined to both of the two side surfaces parallel to the YZ plane of the multi-emitter semiconductor laser bar 2, the side surface facing the negative direction of the X axis and the side surface facing the positive direction.

The material forming the holding member 27 and the material forming the collimating lens array 4 are preferably the same. The third joint member 11, the fourth joint member and the fifth joint member 13 are, for example, adhesives. The third joint member 11 is preferably made of an ultraviolet curable resin adhesive. The heat resistance strength of the fourth joint member and the heat resistance strength of the fifth joint member 13 are preferably higher than the heat resistance strength of the third joint member 11 .

FIG. 14 shows an arc 4a that indicates the warp of the collimating lens array 4. Arc 4a is indicated by a dashed line. The warp of the collimator lens array 4 is the warp of the collimator lens array 4 on a plane that is perpendicular to the propagation direction of the multiple beams output from the multi-emitter semiconductor laser bar 2 and includes the collimator lens array 4 . As indicated by the arc 4a, the direction of warp of the collimating lens array 4 in FIG. 14 is the direction of protruding to the negative side of the Y axis.

In the optical module 1C, the direction of the warp of the collimating lens array 4 is a plane orthogonal to the propagation direction of the plurality of beams output from the multi-emitter semiconductor laser bar 2 and the plurality of light emitting points on the plane including the plurality of light emitting points 2a. It is the same as the warp direction of the line 2b connecting 2a.

Next, a method for manufacturing the optical module 1C according to Embodiment 4 will be described. The direction of warpage of a line 2b connecting a plurality of light emitting points 2a on a plane orthogonal to the propagation direction of a plurality of beams output from the multi-emitter semiconductor laser bar 2 and including the plurality of light emitting points 2a is measured. That is, the direction of warp in the Y-axis direction of the multi-emitter semiconductor laser bar 2 is measured.

Next, the multi-emitter semiconductor laser bar 2 is fixed on the upper surface of the cooling structure 3 . The warp direction of the multi-emitter semiconductor laser bar 2 may be measured after fixing the multi-emitter semiconductor laser bar 2 to the upper surface of the cooling structure 3 .

Next, the warp direction of the collimating lens array 4 on a plane that is perpendicular to the propagation direction of the beams collimated by the collimating lens array 4 and includes the collimating lens array 4 is measured.

Next, the collimating lens array 4 is joined to the holding member 27 by the fifth joining member 13. The warp direction of the collimating lens array 4 may be measured after the collimating lens array 4 is joined to the holding member 27 .

Next, using the holding member 27, the measured warp direction of the collimating lens array 4 is made the same as the measured warp direction of the line 2b connecting the plurality of light emitting points 2a. Specifically, it is fixed to the collimator lens array 4 so that the measured warp direction of the collimator lens array 4 is the same as the measured warp direction of the line 2b connecting the plurality of light emitting points 2a. A member 27 is secured to the upper surface of the cooling structure 3 by means of a third joining member 11 . Thereby, the optical module 1C is manufactured.

It should be noted that either the process of measuring the warp direction of the line 2b connecting the plurality of light emitting points 2a or the process of measuring the warp direction of the collimating lens array 4 may be performed first. Moreover, the fixing of the multi-emitter semiconductor laser bar 2, the cooling structure 3, the holding member 27, and the collimator lens array 4 may be performed in any order.

As described above, in the optical module 1C according to Embodiment 4, the warp direction of the collimating lens array 4 is the same as the warp direction of the line connecting the plurality of light emitting points 2a of the multi-emitter semiconductor laser bar 2. Therefore, it is suppressed that a plurality of beams output from the multi-emitter semiconductor laser bar 2 do not go straight. Therefore, the optical module 1C can suppress the occurrence of propagation loss of the output laser light. In other words, the optical module 1C can efficiently propagate the output laser light.

In the fourth embodiment, the optical module 1C is manufactured by making the direction of warp of the collimating lens array 4 the same as the direction of warp of the line 2b connecting the plurality of light emitting points 2a. Therefore, according to the optical module manufacturing method according to the fourth embodiment, it is possible to manufacture the optical module 1C that suppresses the occurrence of propagation loss of the output laser light.

Also, in the optical module 1C, a holding member is not required on the lower side of the collimator lens array 4, that is, on the negative side of the Y axis. Thereby, the shape of the cooling structure 3 in the Y-axis direction can be thinned. Therefore, it is possible to reduce the size of the cooling structure 3 in the Y-axis direction.

Also, since the collimator lens array 4 extending in the X-axis direction is a cantilever beam, the shape of the cooling structure 3 in the X-axis direction can be made thinner. Therefore, it is possible to reduce the size of the cooling structure 3 in the X-axis direction.

Embodiment 5.
FIG. 15 is a diagram schematically showing a side surface of an optical module 1D according to the fifth embodiment. FIG. 15 schematically shows a side surface of the optical module 1D parallel to the YZ plane, which is a plane containing the Y axis and the Z axis. In Embodiment 5, differences from Embodiment 4 will be mainly described. It should be noted that FIG. 15 does not show a power supply mechanism for supplying current to the multi-emitter semiconductor laser bar 2 .

The optical module 1D has a multi-emitter semiconductor laser bar 2, a cooling structure 3, and a collimating lens array 4 similar to the optical module 1C of the fourth embodiment. The arrangement positions of the multi-emitter semiconductor laser bar 2, the cooling structure 3, and the collimating lens array 4 in the optical module 1D are the same as in the optical module 1C.

The optical module 1D further has a lens unit 35 including a collimator lens array 4 for collimating the multiple beams output by the multi-emitter semiconductor laser bar 2. That is, the optical module 1D has a lens unit 35 instead of the lens unit 25 as compared with the optical module 1C.

The lens unit 35 has a holding member 37 for holding the collimating lens array 4. The optical module 1D further has a sixth joint member 14 joining the cooling structure 3 and the holding member 37 of the lens unit 35 . The holding member 37 supports the collimating lens array 4 in a direction orthogonal to the direction of warp of the collimating lens array 4, and allows a plurality of beams collimated by the collimating lens array 4 to pass therethrough.

The holding member 37 extends in the Z-axis direction. The shape of the holding member 37 is, for example, a columnar shape such as a square column extending in the Z-axis direction. Below, the case where the shape of the holding member 37 is a quadrangular prism extending in the Z-axis direction will be described. The holding member 37 is a cuboid having a surface parallel to the XY plane, a surface parallel to the YZ plane, and a surface parallel to the XZ plane. The holding member 37 is longer than the holding member 27 in the propagation direction of the multiple beams output from the multi-emitter semiconductor laser bar 2 . That is, the holding member 37 is longer than the holding member 27 in the Z-axis direction.

A part of the bottom surface of the holding member 37 is joined to the upper surface of the cooling structure 3 by the sixth joining member 14 . Both the bottom surface of the holding member 37 and the top surface of the cooling structure 3 are parallel to the XZ plane.

The sixth joint member 14 is, for example, an adhesive. The sixth joint member 14 is preferably made of an ultraviolet curable resin adhesive.

The optical module 1D further has optical elements 8a, . . . , 8n that the optical module 1C does not have. The optical elements 8a, . . . , 8n of the optical module 1D are arranged at the same positions as the optical elements 8a, . The optical module 1D further has a ninth joining member (not shown) joining the optical elements 8a, . . . For example, each of the ninth joint members is made of the same material as the fifth joint member 13 .

The optical elements 8a, . The front surfaces of the optical elements 8a, . . . , 8n are planes parallel to the XY plane facing the negative direction of the Z axis. The back surfaces of the optical elements 8a, . . . , 8n are planes parallel to the XY plane facing the positive direction of the Z axis. A plurality of beams output by the collimating lens array 4 enter from the front surface of the optical elements 8a, . The longitudinal direction of the optical elements 8a, . . . , 8n is the direction of the X-axis. For example, in the optical elements 8a, . . . , 8n, the positive and negative X-axis shapes are symmetrical with respect to the center in the longitudinal direction.

The holding member 37 supports the optical elements 8a, . The side surfaces of the optical elements 8a, . . . , 8n parallel to the YZ plane are the fifth surfaces.

In the optical module 1D, the optical elements 8a, . . . , 8n are arranged in the order of the optical elements 8a, . It is The center of the multi-emitter semiconductor laser bar 2 on a plane parallel to the XY plane, the center of the collimator lens array 4 on a plane parallel to the XY plane, and the optical elements 8a, . is parallel to the Z-axis.

In Embodiment 5, for each of the optical elements 8a, . It is the same as the warp direction of the connecting line 2b. When manufacturing the optical module 1D, for each of the optical elements 8a, . That is, the warpage of each of the optical elements 8a, . . . , 8n in the Y-axis direction is measured. Next, the direction of warpage of each of the measured optical elements 8a, .

As in the third embodiment, processing for measuring the warp directions of the optical elements 8a, . . . , 8n, processing for measuring the warp directions of the multi-emitter semiconductor laser bar 2, and The process of measuring the orientation of may be executed in any order. Moreover, fixing the multi-emitter semiconductor laser bar 2, the cooling structure 3, the holding member 27, the collimating lens array 4, and the optical elements 8a, . . . , 8n may be performed in any order. Also, the optical module 1D may have one optical element 8a instead of a plurality.

In the optical module 1D, the direction of warp of the collimator lens array 4 and the direction of warp of each of the optical elements 8a, . A relatively large number of beams out of the plurality of beams output from the multi-emitter semiconductor laser bar 2 become beams 10 that travel straight. Therefore, the optical module 1D can suppress the occurrence of propagation loss of the output laser light.

As described above, in the optical module 1D according to the fifth embodiment, the direction of warp of the collimating lens array 4 and the direction of warp of each of the optical elements 8a, . It is the same as the warp direction of the line 2b connecting the light emitting points 2a. Therefore, it is suppressed that a plurality of beams output from the multi-emitter semiconductor laser bar 2 do not travel straight. Therefore, the optical module 1D can suppress the occurrence of propagation loss of the output laser light. In other words, the optical module 1D can efficiently propagate the output laser light.

In the fifth embodiment, the direction of warp of the collimating lens array 4 and the direction of warp of each of the optical elements 8a, . An optical module 1D is manufactured. Therefore, according to the method for manufacturing an optical module according to the fifth embodiment, it is possible to manufacture an optical module 1D that suppresses the occurrence of loss in propagation of output laser light.

The configurations shown in the above embodiments are only examples, and can be combined with other known techniques, or can be combined with other embodiments, without departing from the scope of the invention. It is also possible to omit or change part of the configuration.

1, 1A, 1B, 1C, 1D optical module, 2 multi-emitter semiconductor laser bar, 2a multiple light emitting points, 2b line connecting multiple light emitting points, 3 cooling structure, 4 collimating lens array, 4a arc, 5, 27, 37 holding member, 6 first joint member, 7 second joint member, 8a, ..., 8n optical element, 9a, ..., 9n joint member, 10 straight beam, 11 third joint member, 13 Fifth joint member, 14 Sixth joint member, 20 Beam that does not go straight, 25, 35 Lens unit.

Claims

a multi-emitter semiconductor laser bar comprising a plurality of light emitting points;
a lens unit having a collimating lens array for collimating a plurality of beams output from the multi-emitter semiconductor laser bar;
with
The lens unit further has a holding member that holds the collimating lens array,
A warp direction of the collimating lens array on a plane that is orthogonal to the propagation direction of the plurality of beams and that includes the collimating lens array is a plane that is orthogonal to the propagation direction and includes the plurality of light emitting points. is the same as the warp direction of the line connecting the plurality of light emitting points on the plane,
The holding member supports the collimating lens array from one side in a first direction orthogonal to the direction of warp of the collimating lens array and the propagation direction.
An optical module characterized by:
Further comprising one or more optical elements arranged in front of the lens unit in the direction in which the plurality of beams propagate,
For each of the optical elements, the warp direction on a plane that is orthogonal to the propagation direction and includes the optical element is the same as the warp direction of the line that connects the plurality of light emitting points.
2. The optical module according to claim 1, wherein:
further comprising a cooling structure for dissipating heat generated by the multi-emitter semiconductor laser bar;
The multi-emitter semiconductor laser bar is positioned on top of the cooling structure,
The holding member extends from the cooling structure in a direction parallel to the propagation direction, with the bottom surface of the holding member joined to the top surface of the cooling structure.
3. The optical module according to claim 2, characterized by:
the holding member has a first surface orthogonal to the first direction and a second surface parallel to the top surface of the cooling structure, which is the bottom surface;
The multi-emitter semiconductor laser bar has a third surface orthogonal to the first direction,
The collimating lens array has a fourth surface orthogonal to the first direction,
The holding member has the first surface bonded to the third surface and the fourth surface, and the second surface bonded to the top surface of the cooling structure.
4. The optical module according to claim 3, characterized by:
each of the optical elements has a fifth surface perpendicular to the first direction;
The holding member supports each of the optical elements from one side in the first direction by bonding the first surface to the fifth surface.
5. The optical module according to claim 4, characterized by:
An optical module manufacturing method for manufacturing an optical module having a multi-emitter semiconductor laser bar having a plurality of light emitting points and a collimating lens array for collimating a plurality of beams output from the multi-emitter semiconductor laser bar,
a first step of measuring the direction of warpage of a line connecting the plurality of light emitting points on a plane orthogonal to the propagation direction of the plurality of beams and containing the plurality of light emitting points;
a second step of measuring the warp orientation of the collimating lens array in a plane orthogonal to the propagation direction and containing the collimating lens array;
supporting the collimating lens array from one side in a first direction orthogonal to the direction of warp of the collimating lens array and the propagation direction of the plurality of beams, and measuring the direction of the warping of the collimating lens array, a third step of making the direction of the warp of the line connecting the plurality of measured light emitting points the same;
A method of manufacturing an optical module, comprising:
The multi-emitter semiconductor laser bar is disposed on an upper surface of a cooling structure for dissipating heat generated by the multi-emitter semiconductor laser bar,
In the third step, the bottom surface of the holding member is joined to the top surface of the cooling structure, and the holding member extends from the cooling structure in a direction parallel to the propagation direction.
7. The method of manufacturing an optical module according to claim 6, wherein:
The optical module further comprises one or more optical elements,
a fourth step of measuring, for each of said optical elements, the direction of warpage in a plane orthogonal to said propagation direction and containing said optical element;
The optical element is supported by the holding member from one side in the first direction, and the measured warp direction of each of the optical elements is the same as the measured warp direction of the line connecting the plurality of light emitting points. a fifth step to
8. The method of manufacturing an optical module according to claim 7, further comprising: