Light source unit, and laser processor

Abstract

To provide a light source unit capable of suppressing deterioration of bonding performance between a collimator lens and a beam twister.SOLUTION: A light source unit 10 includes a laser element 20, a collimating lens 31, and a beam twister 32. The laser element 20 emits a laser beam LB. The collimating lens 31 collimates the laser beam LB emitted from the laser element 20. The beam twister 32 rotates the exit angle of the laser beam LB that has passed through the collimating lens 31. The collimating lens 31 and the beam twister 32 are joined to each other by optical contact.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a light source unit and a laser processing device. [Background technology]

[0002] Patent Document 1 discloses a laser emitter module having an emitter, a collimating lens (first axis collimator), and a beam twister (beam conditioning optical member). The collimating lens collimates the laser light output from the emitter in the fast axis direction. The beam twister rotates the incident laser light by about 90 degrees and outputs it.

[0003] Here, Patent Document 1 does not disclose a method for fixing the collimator lens and the beam twister. However, for example, it is conceivable to bond the two optical components using a bonding material such as a resin adhesive, as disclosed in Patent Document 2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-095916 A [Patent Document 2] JP 2019-140240 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the conventional invention, when the collimator lens and the beam twister are bonded together with a bonding material, there is a risk that the bonding performance between the collimator lens and the beam twister may deteriorate.

[0006] Specifically, if the laser light is scattered outside the optical path as it passes through the collimating lens and becomes stray light, the stray laser light may be emitted toward the bonding material that bonds the collimating lens and the beam twister, which may degrade the bonding performance.

[0007] The present invention has been made in view of the above-mentioned points, and an object of the present invention is to suppress deterioration of the bonding performance between the collimator lens and the beam twister. [Means for solving the problem]

[0008] The first invention is a light source unit comprising a laser element that emits laser light, a collimating lens that collimates the laser light emitted from the laser element, and a beam twister that rotates the emission angle of the laser light that has passed through the collimating lens, the collimating lens and the beam twister being joined to each other by optical contact.

[0009] In the first aspect of the present invention, it is possible to suppress deterioration of the bonding performance between the collimator lens and the beam twister.

[0010] Specifically, if the laser light is scattered outside the optical path as it passes through the collimating lens and becomes stray light, the stray laser light may be emitted toward the bonding material that bonds the collimating lens and the beam twister, which may degrade the bonding performance.

[0011] In contrast, by bonding the collimator lens and the beam twister to each other by optical contact, the problem of the bonding material being deteriorated by stray light does not occur, and the bonding performance can be ensured.

[0012] A second invention is a light source unit according to the first invention, comprising a holder having a support surface extending along the emission direction of the laser light, the support surface supporting the collimating lens and the beam twister, and the holder, the collimating lens and the beam twister being joined to each other by optical contact.

[0013] In the second aspect of the present invention, it is possible to suppress deterioration of the bonding performance between the holder and the collimator lens and between the holder and the beam twister.

[0014] Specifically, when the holder is bonded to the collimator lens and the beam twister using a bonding material, the laser light becomes stray light when passing through the collimator lens and the beam twister and is emitted toward the bonding material, which may degrade the bonding performance.

[0015] In contrast, by bonding the holder to the collimator lens and the beam twister by optical contact, the bonding performance can be ensured without causing the problem of the bonding material deteriorating due to stray light.

[0016] A third invention is the light source unit according to the first or second invention, wherein a joint surface between the collimator lens and the beam twister is flat.

[0017] In the third aspect of the present invention, the joining surface is formed to be flat, thereby improving workability.

[0018] A fourth invention is a laser processing apparatus comprising a light source unit of the first or second invention, a group of focusing lenses that focus the laser light emitted from the light source unit, a transmission fiber that transmits the laser light focused by the group of focusing lenses, and a laser head that emits the laser light transmitted by the transmission fiber.

[0019] In a fourth aspect of the present invention, a laser processing apparatus can be provided that includes a light source unit, a condenser lens group, a transmission fiber, and a laser head. Effect of the Invention

[0020] According to the present invention, it is possible to suppress deterioration of the bonding performance between the collimator lens and the beam twister. [Brief description of the drawings]

[0021] [Figure 1] 1 is a diagram showing a schematic configuration of a laser processing apparatus according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a perspective view showing a configuration of a light source unit. [Diagram 3] FIG. 2 is a side cross-sectional view showing the configuration of the light source unit. [Figure 4] FIG. 2 is a side cross-sectional view showing the configuration of an optical system unit. [Diagram 5] FIG. 2 is a plan view showing the configuration of an optical system unit. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its applications, or its uses.

[0023] As shown in FIG. 1, the laser processing apparatus 1 includes a laser oscillator 2, a transmission fiber 4, and a laser head 5.

[0024] The laser oscillator 2 has a condenser lens group 3 and a light source unit 10. The light source unit 10 emits laser light LB. The light source unit 10 will be described in detail later. The condenser lens group 3 has a role of condensing the laser light LB emitted from the light source unit 10 and inputting it to the input end of the transmission fiber 4, and is shown as a single lens in the figure for convenience. In reality, the condenser lens group 3 may include multiple optical elements, such as lenses, mirrors, diffraction gratings, and beam splitters.

[0025] The transmission fiber 4 transmits the laser light LB. An incident end of the transmission fiber 4 is connected to the laser oscillator 2. An exit end of the transmission fiber 4 is connected to a laser head 5.

[0026] The laser head 5 emits the laser light LB transmitted by the transmission fiber 4 toward the workpiece W. The laser head 5 includes a collimator lens 6 and a condenser lens .

[0027] The collimating lens 6 collimates the laser light LB transmitted by the transmission fiber 4. The condensing lens 7 condenses the laser light LB collimated by the collimating lens 6. The laser light LB condensed by the condensing lens 7 is emitted to the workpiece W.

[0028] As shown in FIGS. 2 and 3, the light source unit 10 includes a first block 11, a second block 12, an insulating layer 13, a submount 15, a laser element 20, and an optical system unit 30. The first block 11 and the second block 12 are electrically connected to each other.

[0029] The first block 11 is conductive. The first block 11 is mainly made of copper (Cu). In the first block 11, a copper block is plated with, for example, nickel (Ni) and gold (Au) in that order. A water-cooled jacket (not shown) is connected to the first block 11.

[0030] On the upper surface of the first block 11, a submount 15 and a laser element 20 are disposed.

[0031] The insulating layer 13 has insulating properties. The insulating layer 13 is made of polyimide, ceramic, etc. The insulating layer 13 is sandwiched between the first block 11 and the second block 12.

[0032] The laser element 20 has a plurality of emitters (not shown). The lower surface of the laser element 20 is a positive electrode, and the upper surface is a negative electrode. When a current flows from the positive electrode to the negative electrode, the laser element 20 emits laser light LB from each of the plurality of emitters at the light emitting surface. The laser element 20 is mounted on the submount 15. The laser element 20 is electrically connected to the submount 15.

[0033] The laser element 20 and the submount 15 are disposed at an end portion on the side of the emission direction of the laser light LB (the direction indicated by the arrow in FIG. 2) on the upper surface of the first block 11. The submount 15 is bonded to the upper surface of the first block 11 by, for example, soldering.

[0034] The first block 11 functions as an electrode block that is electrically connected to the laser element 20 via the submount 15 .

[0035] The second block 12 is conductive. The second block 12 is mainly made of copper (Cu). In the second block 12, a copper block is plated with, for example, nickel (Ni) and gold (Au) in that order. The second block 12 is disposed opposite the first block 11.

[0036] The second block 12 is provided on the laser element 20 and the insulating layer 13. The second block 12 is electrically connected to the laser element 20 via a bump (not shown). The second block 12 functions as an electrode block that is electrically connected to the laser element 20.

[0037] <Optical unit> The optical system unit 30 is disposed forward in the emission direction from the light emitting surface of the laser element 20. The optical system unit 30 includes a collimator lens 31, a beam twister 32, and a holder 33.

[0038] The collimator lens 31 is disposed opposite to the light emitting surface of the laser element 20. The collimator lens 31 collimates the spread of the laser light LB emitted from the laser element 20 in the fast axis direction.

[0039] The beam twister 32 is disposed on the opposite side of the collimator lens 31 from the laser element 20. The beam twister 32 rotates the emission angle of the laser light LB that has passed through the collimator lens 31. Specifically, the beam twister 32 rotates the laser light LB that has been emitted from the laser element 20 and passed through the collimator lens 31 by approximately 90 degrees.

[0040] Here, the collimator lens 31 and the beam twister 32 are joined together by optical contact. Optical contact is a technique for joining materials by utilizing the attractive force between them, without using any bonding material.

[0041] Specifically, the bonding surfaces of the collimator lens 31 and the beam twister 32 are polished with high precision, and the bonding surfaces are brought into close contact with each other and intermolecular forces are exerted to bond the collimator lens 31 and the beam twister 32 together.

[0042] As a result, even if the laser light LB is scattered outside the optical path and becomes stray light M when passing through the collimator lens 31 as shown in FIG. 5, the bonding performance can be ensured without causing the problem of the bonding material being deteriorated by the stray light M.

[0043] Here, it is preferable that the joint surface between the collimator lens 31 and the beam twister 32 is flat. By forming the joint surface to be flat in this manner, workability is improved.

[0044] The holder 33 holds the collimator lens 31 and the beam twister 32 and determines the positional relationship between the collimator lens 31 and the beam twister 32. The holder 33 is formed of, for example, a glass plate. The holder 33 is provided above the collimator lens 31 and the beam twister 32. The holder 33 is bonded to the second block 12 by a bonding material 35.

[0045] The holder 33 has a support surface 33a extending along the emission direction of the laser light LB. The support surface 33a of the holder 33 supports the collimator lens 31 and the beam twister 32. The holder 33, the collimator lens 31, and the beam twister 32 are joined to each other by optical contact.

[0046] Specifically, the support surface 33a of the holder 33 and the bonding surfaces (top surfaces in FIG. 4) of the collimating lens 31 and the beam twister 32 that face the support surface 33a are polished with high precision, and the support surface 33a of the holder 33 and the bonding surfaces (top surfaces in FIG. 4) of the collimating lens 31 and the beam twister 32 are brought into close contact with each other and intermolecular forces are exerted to bond the holder 33 to the collimating lens 31 and the beam twister 32.

[0047] In this way, by bonding the holder 33 to the collimator lens 31 and the beam twister 32 by optical contact, the bonding material is not deteriorated due to the stray light M, and the bonding performance can be ensured.

[0048] In the optical system unit 30, the laser light LB emitted from the laser element 20 is first collimated in the fast axis direction by the collimator lens 31, so that the spread of the laser light LB in the fast axis direction can be minimized.

[0049] Furthermore, by rotating the laser light LB that has passed through the collimator lens 31 by the beam twister 32, the overlap with adjacent emitters in the laser element 20 can be minimized and avoided with respect to the spread in the slow axis direction as well.

[0050] This makes it possible to minimize the pitch (arrangement interval) according to the width of the multiple emitters in the laser element 20, and makes it possible to output high-power laser light with high beam quality. [Industrial Applicability]

[0051] INDUSTRIAL APPLICABILITY As described above, the present invention has the highly practical effect of being able to suppress deterioration of the bonding performance between the collimator lens and the beam twister, and is therefore extremely useful and has high industrial applicability. [Explanation of symbols]

[0052] 1 Laser processing equipment 3. Condenser lens group 4 Transmission Fiber 5 Laser Head 10 Light source unit 20 Laser element 31 Collimating Lens 32 Beam Twister 33 Holder 33a Support surface LB laser light

Claims

1. A laser element that emits laser light; a collimator lens for collimating the laser light emitted from the laser element; a beam twister that rotates an emission angle of the laser light that has passed through the collimator lens; The collimating lens and the beam twister are joined to each other by optical contact. Light source unit.

2. The light source unit according to claim 1, a holder having a support surface extending along an emission direction of the laser light, the support surface supporting the collimator lens and the beam twister; The holder, the collimating lens and the beam twister are joined to each other by optical contact. Light source unit.

3. 3. The light source unit according to claim 1, The joint surface between the collimator lens and the beam twister is flat. Light source unit.

4. A light source unit according to claim 1 or 2; a condenser lens group that condenses the laser light emitted from the light source unit; a transmission fiber for transmitting the laser light condensed by the condenser lens group; a laser head that emits the laser light transmitted through the transmission fiber; Laser processing equipment.

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