Laser oscillator and laser processing device with them

Abstract

To provide a laser oscillator capable of performing an output measurement and an output correction of a laser light with a small and simple construction.SOLUTION: A laser oscillator 70 comprises: a plurality of laser light sources 12 that emits a module layer beam LBM, respectively; a partial reflection mirror 13; an optical detection device 14; a second mirror 23; and a dumper 24. The second mirror 23 is moved on an optical path and an outside of the optical path of a coupling laser beam LB to which the plurality of module layer beams LBM is coupled. A calculation part 52 calculates an output the coupling laser beam LB on the basis of the output of each module layer beam LBM detected by the optical detection device 14. In the case where a difference between an output value and a target value of the coupling laser beam LB exceeds a predetermined range, a control part 50 enters the coupling laser beam LB into the damper 24 by moving the second mirror 23, and in addition, controls an output of the laser light source 12.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a laser oscillator and a laser processing apparatus including the same. [Background technology]

[0002] In recent years, the development of laser processing equipment using direct diode laser (hereinafter sometimes referred to as DDL) oscillators using laser diodes or semiconductor laser elements such as laser diodes has accelerated. This laser oscillator can obtain high output exceeding several kW by combining laser light emitted from multiple semiconductor laser elements.

[0003] On the other hand, it is known that the output of semiconductor laser elements decreases over time. Therefore, in order to consistently obtain good processing results with a laser processing device, it is necessary to correct the output of the laser light emitted from the laser oscillator at an appropriate time and maintain the output of the laser light within an allowable range.

[0004] Conventionally, for example, the output of a laser beam is measured by a power meter installed in a processing area or the like, and the output of the laser beam is corrected based on the measurement result. Patent Document 1 discloses a configuration in which the output of a laser beam is measured by a power meter arranged inside a housing of a laser oscillator, and the output of the laser beam is corrected based on the measurement result. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-041428 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when measuring the output of a laser beam using a power meter and then correcting the output based on the measurement results, the following problems may occur.

[0007] First, since the power meter is not necessary during laser processing, it takes time to install the power meter in the laser processing device every time the output of the laser light is measured and corrected. Also, if the power meter is not installed properly, there is a risk that the correct measurement results will not be obtained, or that the power meter, the laser processing device, or the workpiece to be processed will be damaged.

[0008] Furthermore, in the conventional configuration disclosed in Patent Document 1, depending on the specifications of the power meter, there were issues such as limited installation positions within the housing due to its large size, and slow response speed to fluctuations in the output of the laser light.

[0009] The present disclosure has been made in consideration of the above points, and has an object to provide a laser oscillator that is small and has a simple configuration and is capable of measuring and correcting the output of laser light, and a laser processing apparatus equipped with the same. [Means for solving the problem]

[0010] In order to achieve the above object, the laser oscillator of the present disclosure comprises at least a laser light source that emits laser light, a light branching member that branches a portion of the laser light, a photodetector that receives the portion of the laser light branched by the light branching member and outputs an electrical signal, a movable mirror that is movably provided to be positioned respectively on and off the optical path of the laser light, a light receiving unit that is positioned farther away from the movable mirror as viewed from the laser light source, and a control unit that calculates an output of the laser light based on the magnitude of the electrical signal, and is characterized in that when a difference between an output value of the laser light calculated by the control unit and a target value exceeds a predetermined range, the control unit moves the movable mirror on or off the optical path of the laser light to cause the remaining portion of the laser light to be incident on the light receiving unit, and controls the laser light source so that the difference is within the predetermined range.

[0011] The laser processing apparatus according to the present disclosure is characterized in that it at least comprises a laser oscillator, an optical fiber that guides the laser light emitted from the laser oscillator, and a laser head that receives the laser light guided by the optical fiber and irradiates it toward a workpiece. Effect of the Invention

[0012] According to the present disclosure, it is possible to perform laser light output measurement and output correction with a small and simple configuration. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic configuration diagram of a laser processing device according to a first embodiment. [Diagram 2] 2 is a schematic diagram of a main part of a laser processing apparatus during laser processing. FIG. [Diagram 3] 4 is a schematic diagram of a main part of the laser processing device during output correction. FIG. [Figure 4] 13 is a schematic diagram of a main part of a laser processing device during laser processing according to a modified example. FIG. [Diagram 5] 13 is a schematic diagram of a main part of a laser processing device during output correction according to a modified example. FIG. [Figure 6] 11 is a schematic diagram of a main part of a laser processing device during laser processing according to embodiment 2. FIG. [Figure 7] 11 is a schematic diagram of a main part of a laser processing device during output correction according to the second embodiment. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the following description of the preferred embodiments is merely illustrative in nature and is not intended to limit the present disclosure, its application, or its uses.

[0015] (Embodiment 1) [Laser processing equipment configuration] FIG. 1 is a schematic diagram of a laser processing apparatus according to this embodiment, and FIG. 2 is a schematic diagram of a main part of the laser processing apparatus during laser processing.

[0016] For ease of explanation, the power supply 60 of the laser oscillator 70 is omitted in Fig. 2 and the following drawings. Only one laser module 10 is shown. Inside the beam combiner 20, first mirrors 22 are provided according to the number of laser modules 10, but only one first mirror 22 is shown in Fig. 2 and the following drawings.

[0017] In addition, in addition to the components shown in the drawings, a number of components are arranged inside the laser module 10, the beam combiner 20, the focusing optical unit 30, and the laser head 90, but illustration and description of these components are omitted.

[0018] In the following description, the traveling direction of the combined laser light LB, which is described later and is emitted from the beam combiner 20, toward the focusing optical unit 30 may be referred to as the Z direction. The Z direction is also the optical axis direction of the laser light LB inside the fourth housing 31 of the focusing optical unit 30. The arrangement direction of the multiple laser modules 10 may be referred to as the X direction. A direction perpendicular to each of the X direction and the Z direction may be referred to as the Y direction.

[0019] In this specification, "orthogonal" or "parallel" means that the two objects are orthogonal or parallel, including the assembly tolerances and processing tolerances of the laser processing apparatus 100 and its components, and does not mean that the objects being compared are orthogonal or parallel in the strict sense.

[0020] 1, the laser processing apparatus 100 includes a first housing 40, a laser oscillator 70, an optical fiber 80, and a laser head 90. Except for a part of the optical fiber 80, a control unit 50, and a power source 60, the laser oscillator 70 is accommodated inside the first housing 40.

[0021] 1 and 2, the laser oscillator 70 includes a plurality of laser modules 10, a beam combiner 20, and a focusing optical unit 30. The laser oscillator 70 also includes a control unit 50 and a power supply 60.

[0022] The laser module 10 has a laser light source 12 made up of a plurality of laser diodes or laser diode bars that emit laser light of different wavelengths inside the second housing 11. The laser light emitted from the laser light source 12 is synthesized in the laser module 10 to be a module laser light LB M are emitted from the laser modules 10, respectively.

[0023] 2, a partial reflection mirror (light branching member) 13 and a photodetector 14 are disposed inside the second housing 11. The partial reflection mirror 13 is configured to branch the module laser light LB M The majority of the modules, specifically, 99.99% or more of the laser light LB M The partial reflection mirror 13 transmits the module laser beam LB while reflecting the remaining portion toward the photodetector 14. M The reflectance and transmittance of the module laser light LB M This can be appropriately changed depending on the power of the laser beam and the saturation value of the amount of light received by the photodetector 14. The photodetector 14 is a known light receiving element, for example, a photodiode. The function of the photodetector 14 will be described later.

[0024] The beam combiner 20 combines the module laser beams LB emitted from the multiple laser modules 10. M These are combined into one laser beam LB (hereinafter, sometimes referred to as a combined laser beam LB) and made to enter the light collecting optical unit 30. Specifically, each module laser beam LB M The optical axes of the two lenses are brought close to each other or are aligned, and the lenses are coupled so that their optical axes are parallel to each other.

[0025] As shown in FIG. 2, the beam combiner 20 combines a plurality of module laser beams LB MThe third housing 21 includes a third housing 21 into which the laser beam LB is incident, a first mirror 22, a second mirror (movable mirror) 23, and a damper (light receiving section) 24. The third housing 21 includes a plurality of module laser beams LB. M The laser beam LB is incident on the light incident port 21a and the combined laser beam LB is emitted from the light incident port 21b.

[0026] The first mirror 22, the second mirror 23, and the damper 24 are housed inside the third housing 21. In addition, inside the third housing 21, two or more module laser beams LB M A polarizing beam splitter for matching the optical path of two or more modules laser light LB M Mirrors (none of which are shown) are provided for spatially combining the

[0027] The first mirror 22 reflects the module laser light LB incident from the light incident port 21a. M The second mirror 23 reflects the incident module laser light LB M and directs the combined laser beam LB toward the light exit port 21b. The second mirror 23 is configured to be movable so as to be positioned on or off the optical path of the combined laser beam LB traveling inside the third housing 21. In the example shown in Fig. 2, the second mirror 23 is configured to be movable along the Z direction by a drive mechanism (not shown) connected to the second mirror 23. The specific operation of the second mirror 23 and the function of the damper 24 will be described later.

[0028] The focusing optical unit 30 has a fourth housing 31 and a first focusing lens 32 arranged inside the fourth housing 31. A light entrance 31a of the fourth housing 31 is connected to a light exit 21b of the third housing 21. An optical fiber 80 is connected to the light exit 31b of the fourth housing 31. The combined laser light LB combined by the beam combiner 20 enters the focusing optical unit 30 from the light exit 21b of the third housing 21, is focused by the first focusing lens 32, and enters the optical fiber 80.

[0029] The optical fiber 80 guides the incident coupled laser light LB to the laser head 90. The optical fiber 80 has one or more cores (not shown) which are optical waveguides, and a cladding (not shown) which is an optical confinement layer provided so as to surround the core.

[0030] The control unit 50 controls the laser oscillation of the laser oscillator 70. Specifically, the control unit 50 controls the laser oscillation of each laser module 10 by supplying control signals such as an output voltage and an on-time to the power supply 60. It is also possible to control the laser oscillation of each laser module 10 individually. For example, the laser oscillation output and the on-time may be different for each laser module 10.

[0031] The control unit 50 also includes a calculation unit 52. The calculation unit 52 receives the output signal from the photodetector 14 and calculates the module laser light LB based on the output signal. M The control unit 50 calculates the actual output value of each module laser light LB. M The control unit 50 calculates the output value of the combined laser light LB based on the actual output values ​​of the laser light LB from each module. M In addition, control unit 50 controls power supply 60 so that the difference between the target value of the output of laser light LB and the output value calculated by calculation unit 52 falls within the range of the required specifications used for laser processing.

[0032] The calculation unit 52 is configured with, for example, a CPU (Central Processing Unit). In addition to the calculation unit 52, the control unit 50 may include one or more CPUs.

[0033] The control unit 50 also has a storage unit 51, which stores laser processing conditions, such as a target value for the output of the combined laser light LB during laser processing and an operation program for processing. The storage unit 51 is configured with a semiconductor memory such as a random access memory (RAM) or a read only memory (ROM). The storage unit 51 may also be configured with a hard disk drive (HDD) or a solid state drive (SSD). The control unit 50 may also control the operation of a robot (not shown) to which the laser head 90 is attached.

[0034] The display unit 53 is configured to display the laser processing conditions and the contents of the operation program. The display unit 53 may also be configured to display the target value of the output of the combined laser light LB and the calculated output value calculated by the calculation unit 52. The display unit 53 may also display data other than the above. For example, the output value of each module laser light LB calculated by the calculation unit 52 may be displayed. M The display unit 53 usually includes a display device such as a liquid crystal display or an organic EL display.

[0035] As described above, the power supply 60 supplies power for performing laser oscillation to each of the laser modules 10. The power supplied to each laser module 10 may be different in response to a command from the control unit 50. The power supply 60 may also supply power to a moving part of the laser processing apparatus 100, for example, the above-mentioned robot. The power supply 60 may also supply power to a rotation drive mechanism (not shown) connected to an output detection device 210 (see FIGS. 6 and 7) described later. Note that power may be supplied to the moving part of the laser processing apparatus 100 from a separate power supply (not shown).

[0036] By configuring the laser oscillator 70 in this way, it is possible to obtain a high-output laser processing apparatus 100 in which the output of the combined laser light LB exceeds several kW. In this embodiment, four laser modules 10 are mounted on the laser oscillator 70, but this is not particularly limited. The number of laser modules 10 mounted can be appropriately changed depending on the output specifications required for the laser processing apparatus 100 and the output specifications of each laser module 10.

[0037] The laser head 90 has a collimating lens 92 and a second condenser lens 93 inside a fifth housing 91. An optical fiber 80 is connected to a light entrance 91a of the fifth housing 91. The combined laser light LB guided by the optical fiber 80 enters the inside of the fifth housing 91 from the light entrance 91a and further enters the collimating lens 92.

[0038] The collimator lens 92 converts the combined laser beam LB into a parallel beam. The combined laser beam LB transmitted through the collimator lens 92 is condensed by a second condenser lens 93 and is irradiated to the outside from a light exit port 91b of the fifth housing 91.

[0039] For example, in the laser processing apparatus 100 shown in Fig. 1, the laser head 90 emits the combined laser light LB toward the workpiece W, which is an object to be processed and disposed within the processing area 300. The workpiece W is disposed at a predetermined position on the processing table 200. At this time, the combined laser light LB is focused by the second focusing lens 93 so as to be focused on the surface of the workpiece W or near the surface. In this manner, the workpiece W is laser processed.

[0040] [Laser light output correction] FIG. 3 is a schematic diagram of a main part of the laser processing device during output correction.

[0041] 2, during laser processing, the second mirror 23 is located on the optical path of the combined laser light LB. Therefore, the combined laser light LB is reflected by the second mirror 23 and enters the inside of the fourth housing 31 of the light collecting optical unit 30 from the light exit port 21b of the third housing 21. The combined laser light LB then passes through the optical fiber 80 and is irradiated from the laser head 90 toward the workpiece W.

[0042] At this time, the module laser light LB reflected by the partial reflection mirror 13 M A part of the detection laser beam LB P The detection laser light LB is received by the photodetector 14. P This electrical signal is sent to the control unit 50, and the calculation unit 52 calculates the module laser light LB based on the magnitude of the electrical signal. M As described above, the output value of the combined laser beam LB is calculated.

[0043] However, the output characteristics of the laser light source 12 may deteriorate due to heat generation during long-term use, and the output of the combined laser light LB may become lower than the target value even if the laser processing apparatus 100 is operated under the set conditions. If the difference between the actual output of the combined laser light LB and the target value exceeds a predetermined range allowed for laser processing, the required specifications for laser processing may not be satisfied.

[0044] In such a case, the output of the combined laser light LB is corrected to be equal to the target value by correcting the value of the current supplied from the power supply 60 to each laser light source 12. In many cases, as disclosed in Patent Document 1, the output of the combined laser light LB is monitored with a power meter, and the output of the combined laser light LB is corrected based on the result of monitoring.

[0045] In this case, however, the power meter has a slow response speed, so output correction takes time. Also, as described above, the power meter is large in size, so there are restrictions on where it can be placed inside the laser oscillator 70.

[0046] Therefore, in this embodiment, the module laser light LB M An element with high response speed, such as a photodiode, is used as the photodetector 14 for monitoring the output of the laser beam LB. Also, during output correction, the coupled laser beam LB is prevented from being incident on the workpiece W. This will be explained further below.

[0047] 3, when measuring the output, the second mirror 23 is moved out of the optical path of the combined laser light LB. At this time, the combined laser light LB is incident on the damper 24 and is not incident on the focusing optical unit 30. In other words, the combined laser light LB is not irradiated from the laser head 90 toward the workpiece W. The combined laser light LB incident on the damper 24 is converted into heat.

[0048] At this time, the detection laser light LB P The photodetector 14 receives the electric signal. The electric signal output from the photodetector 14 is sent to the control unit 50, and the calculation unit 52 calculates the module laser light LB based on the magnitude of the electric signal. M and further the output value of the combined laser light LB. The control unit 50 controls the power source 60 to change the value of the current supplied to each laser light source 12 so that the difference between the output value of the combined laser light LB and the target value falls within an allowable range, in other words, a predetermined range.

[0049] In the example shown in FIGS. 2 and 3, the module laser light LB M While the detection laser beam LB is being emitted, the photodetector 14 is constantly receiving the detection laser beam LB P However, the present invention is not limited to this. For example, a shutter (not shown) may be provided between the partial reflection mirror 13 and the photodetector 14 to allow the module laser light LB M The detection laser light LB is incident on the photodetector 14 only during the period when the output of the P may be incident on the

[0050] [Effects, etc.] As described above, the laser oscillator 70 according to this embodiment includes at least the laser light source 12, the partial reflection mirror (light branching member) 13, the photodetector 14, the second mirror (movable mirror) 23, and the damper (light receiving unit) 24.

[0051] The laser oscillator 70 is provided with a plurality of laser modules 10 each including a second housing 11 in which at least a laser light source 12, a partial reflection mirror 13, and a photodetector 14 are arranged.

[0052] The laser light source 12 is a module laser light LB M In addition, the module laser light LB emitted from each of the multiple laser light sources 12 is M These are combined with each other and emitted from the laser oscillator 70 as a single combined laser beam LB.

[0053] The second mirror 23 is provided inside the fourth housing 31 so as to be movable to be located on and off the optical path of the combined laser light LB. More specifically, the second mirror 23 is provided inside the fourth housing 31 so as to be movable to be located on and off the optical path of the combined laser light LB, which is different from the optical path leading to the photodetector 14. The damper 24 is also disposed at a position farther away from the laser light source 12 than the second mirror 23.

[0054] The partial reflection mirror 13 reflects the module laser light LB M A part of the module laser light LB is branched off by the partial reflection mirror 13, and the photodetector 14 detects the branched module laser light LB M The detection laser light LB is a part of P and outputs an electrical signal.

[0055] The calculation unit 52 of the control unit 50 calculates the module laser light LB based on the magnitude of the electrical signal. M The calculation unit 52 of the control unit 50 calculates the output of the coupled laser light LB based on the sum of the magnitudes of the electrical signals respectively output from the multiple photodetectors 14.

[0056] When the difference between the output value of the combined laser light LB calculated by the calculation unit 52 of the control unit 50 and the target value exceeds a predetermined range, the control unit 50 moves the second mirror 23 out of the optical path of the combined laser light LB and makes the combined laser light LB incident on the damper 24. Furthermore, the control unit 50 controls each of the multiple laser light sources 12 via the power source 60 so that the difference falls within a predetermined range.

[0057] According to this embodiment, the module laser light LB is small and simple in configuration. M Therefore, the output of the combined laser light LB can be measured, and the output of the combined laser light LB can be corrected based on the measurement result. Also, the labor required for installing a power meter in the processing area 300 for output measurement and output correction can be saved. Also, as described above, if the power meter is improperly installed, there is a risk that the correct measurement result will not be obtained, or that the power meter, the laser processing apparatus 100, or the workpiece W will be damaged.

[0058] On the other hand, according to this embodiment, there is no need to install a power meter in the processing area 300, and there is no risk of such a problem occurring.

[0059] Furthermore, according to this embodiment, the module laser light LB M In order to measure the output of the combined laser light LB, a photodetector 14 using a high-speed response element such as a photodiode is used. M When measuring the output of the detection laser beam LB P Only the light from the laser beam 11 is incident on the photodetector 14, and the remainder is absorbed by the damper 24. This increases the degree of freedom in arranging these components in the second housing 11 and the third housing 21. In addition, since the response speed during output measurement is increased, the output measurement time and therefore the output correction time can be shortened. This reduces the downtime of the laser processing apparatus 100.

[0060] In the laser oscillator 70 of this embodiment, the laser light source 12, the partial reflection mirror 13, and the photodetector 14 are disposed inside the second housing 11 of the laser module 10.

[0061] On the other hand, the second mirror 23 and the damper 24 are disposed inside a third housing 21 of the beam combiner 20. In addition, the third housing 21 is connected to the second housing 11.

[0062] In this way, the output of the combined laser light LB is not measured directly, but the output of the module laser light LB M By measuring the output of the module laser light LB, the amount of light incident on the photodetector 14 can be reduced. This makes it possible to prevent the amount of light received by the photodetector 14, and in turn the magnitude of the electrical signal output by the photodetector 14, from becoming saturated, and the module laser light LB M This allows the output of the combined laser light LB to be measured accurately. Furthermore, the second mirror 23 and the damper 24 are disposed inside the third housing 21, and when measuring the output of the combined laser light LB, the second mirror 23 is moved to cause the combined laser light LB to be absorbed by the damper 24. In this way, the number of dampers 24 that absorb the combined laser light LB can be reduced.

[0063] The laser processing apparatus 100 according to this embodiment includes at least a laser oscillator 70, an optical fiber 80 that guides the combined laser light LB emitted from the laser oscillator 70, and a laser head 90 that receives the combined laser light LB guided by the optical fiber 80 and irradiates it toward the workpiece W.

[0064] By configuring the laser processing apparatus 100 in this manner, it is possible to perform laser processing by irradiating a high-power combined laser beam LB to a workpiece W arranged in a processing area 300 away from the laser oscillator 70. In addition, since the degree of freedom in arranging the photodetector 14 and the damper 24 can be increased when measuring the output of the combined laser beam LB and correcting the output, the laser processing apparatus 100 can be made compact.

[0065] <Modification> FIG. 4 is a schematic diagram of a main part of a laser processing apparatus during laser processing according to a modified example, and FIG. 5 is a schematic diagram of a main part of the laser processing apparatus during output correction.

[0066] For ease of explanation, in FIG. 4 and the following drawings, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed explanations thereof will be omitted.

[0067] 4 and 5 differs from the laser oscillator 70 of the first embodiment shown in Figures 2 and 3 in that a movable mirror 15 and a damper (light receiving unit) 16 are further arranged inside the second housing 11 of the laser module 10. It also differs from the laser oscillator 70 of the first embodiment in that the damper 24 is omitted from the third housing 21 of the beam combiner 20 and the second mirror 23 is fixed in position.

[0068] In this modified example, when the difference between the output value of the combined laser light LB and the target value exceeds a predetermined range, the control unit 50 moves the movable mirror 15 to the module laser light LB M Then, move the module laser light LB M The remaining portion is made to enter the damper 16. Furthermore, the control unit 50 controls each of the plurality of laser light sources 12 so that the above-mentioned difference falls within a predetermined range.

[0069] When the combined laser light LB has a high output exceeding several kW, absorbing it with a single damper 24 increases the amount of heat generated in the damper 24, which may adversely affect the damper 24 itself and the optical components arranged inside the third housing 21.

[0070] Therefore, as shown in this modification, by providing a movable mirror 15 and a damper 16 for each second housing 11 of the laser module 10, it is possible to disperse the positions of heat generation caused by absorption of the combined laser light LB during output measurement and output correction of the combined laser light LB. In this way, it is possible to prevent the temperature from rising too much locally, and it is possible to stabilize the output characteristics of the combined laser light LB incident on the optical fiber 80.

[0071] (Embodiment 2) FIG. 6 is a schematic diagram of a main part of the laser processing apparatus during laser processing according to the second embodiment, and FIG. 7 is a schematic diagram of a main part of the laser processing apparatus during output correction according to the second embodiment.

[0072] The laser processing apparatus 100 of this embodiment shown in FIGS. 6 and 7 differs from the laser processing apparatus 100 of the first embodiment and the modified examples in that an output detection device 210 is attached to the processing table 200.

[0073] Also, it differs from the laser oscillator 70 of the first embodiment in that the damper 24 is omitted from the third housing 21 of the beam combiner 20 and the second mirror 23 is fixed in position. It also differs from the laser processing apparatus 100 of the modified example in that the movable mirror 15 and the damper 16 are not provided in each of the second housings 11.

[0074] The output detection device 210 has a support 211, a first arm 212, and a second arm 213. The base end of the support 211 is rotatably attached to the processing table 200, and the rotation axis in this case is perpendicular to the surface of the processing table 200. In addition, a damper (light receiving unit) 216 is attached to the tip of the support 211.

[0075] In addition, the base ends of the first arm 212 and the second arm 213 are both attached to a support 211. The first arm 212 is attached at a position closer to the processing table 200 than the second arm 213. A photodetector 214 is attached to the tip of the first arm 212, and a partial reflection mirror 215 is attached to the tip of the second arm 213. When the support 211 rotates, the first arm 212 and the second arm 213 rotate, and accordingly, the photodetector 214 and the partial reflection mirror 215 rotate in a plane parallel to the surface of the processing table 200. The photodetector 214, the partial reflection mirror 215, and the damper 216 are disposed in this order at positions closer to the surface of the processing table 200.

[0076] As shown in FIG. 6, during laser processing, the photodetector 214 and the partial reflection mirror 215 are positioned outside the optical path of the combined laser light LB directed toward the workpiece W from the light emission port 91b provided in the fifth housing 91 of the laser head 90.

[0077] On the other hand, when measuring the output of the combined laser beam LB, as shown in FIG. 7, the support 211 rotates so that the photodetector 214 and the partial reflection mirror 215 are positioned on the optical path of the combined laser beam LB.

[0078] The partial reflection mirror 215 reflects most of the combined laser light LB, specifically, 99.99% or more of the combined laser light LB, toward the dumper 216. Meanwhile, the remaining part of the combined laser light LB passes through the partial reflection mirror and is incident on the photodetector 214. The reflectance and transmittance of the combined laser light LB at the partial reflection mirror 215 can be appropriately changed according to the power of the combined laser light LB and the saturation value of the amount of light received by the photodetector 214. The photodetector 214, like the photodetector 14, is an element with a high response speed, such as a photodiode.

[0079] The laser processing apparatus 100 according to this embodiment includes at least a laser oscillator 70, an optical fiber 80 that guides the combined laser light LB emitted from the laser oscillator 70, and a laser head 90 that receives the combined laser light LB guided by the optical fiber 80 and irradiates it toward the workpiece W.

[0080] The laser processing apparatus 100 also includes a processing table 200 that supports the workpiece W, and an output detection device 210 attached to the processing table 200. The output detection device 210 has a photodetector 214, a partial reflection mirror 215, and a damper (light receiving unit) 216. The photodetector 214, the partial reflection mirror 215, and the damper 216 are all disposed outside the processing area 300.

[0081] The partial reflection mirror 215 can be said to be an integrated member of the partial reflection mirror (light branching member) 13 and the second mirror (movable mirror) 23 in the first embodiment. However, the partial reflection mirror 13 reflects the module laser light LBM , whereas the partially reflecting mirror 215 reflects most of the combined laser beam LB.

[0082] The damper 216 is disposed between the laser head 90 and the processing table 200 .

[0083] The partial reflection mirror 215 is disposed between the laser head 90 and the processing table 200 at a position at the same height as the damper 216 with respect to the surface of the processing table 200 as a reference.

[0084] The photodetector 214 is disposed between the laser head 90 and the processing table 200 and at a position closer to the processing table 200 than the partial reflection mirror 215 is.

[0085] The control unit 50 receives a portion of the combined laser beam LB and calculates the output of the combined laser beam LB based on the magnitude of the electrical signal output by the photodetector 214.

[0086] When the difference between the output value of the combined laser light LB calculated by the control unit 50 and the target value exceeds a predetermined range, The control unit 50 moves the partial reflection mirror 215 onto the optical path of the combined laser light LB to make a part of the combined laser light LB incident on the photodetector 214 and the remaining part of the combined laser light LB incident on the damper 216. Furthermore, the control unit 50 controls each of the multiple laser light sources 12 so that the difference described above falls within a predetermined range.

[0087] By configuring the laser processing apparatus 100 in this manner, it is possible to perform laser processing by irradiating a high-power combined laser beam LB to a workpiece W arranged in a processing area 300 away from the laser oscillator 70. Also, when measuring the output of the combined laser beam LB or correcting the output, the photodetector 214, the partial reflection mirror 215, and the damper 216 can each be disposed outside the laser oscillator 70. This allows the laser oscillator 70, and therefore the laser processing apparatus 100, to be made smaller.

[0088] In addition, by positioning the photodetector 214 between the laser head 90 and the processing table 200 and closer to the processing table 200 than the partial reflection mirror 215, the actual output of the combined laser light LB irradiated toward the workpiece W can be reliably measured.

[0089] Consider the case where the photodetector 14 is disposed inside the laser module 10, as shown in the first embodiment and the modified example. In this case, the module laser light LB M Even if a malfunction occurs in a member on the optical path of the combined laser beam LB and the output of the combined laser beam LB emitted from the laser head 90 does not reach the target value, this cannot be detected.

[0090] On the other hand, according to the present embodiment, when measuring the output of the combined laser light LB, the photodetector 214 is disposed at a position outside the laser head 90 and closest to the workpiece W. M If a malfunction occurs in a component on the optical path of the combined laser light LB, causing a drop in the output of the combined laser light LB, this can be reliably detected. If the photodetector 214 is located inside the processing area 300, the photodetector 214 may be irradiated with the reflected light of the combined laser light LB reflected by the workpiece W, or spatters, fumes, and the like generated by melting the workpiece W during laser processing may adhere to the photodetector 214. In order to prevent these from happening, it is preferable to place the photodetector 214 outside the processing area 300. This also applies to the partially reflecting mirror 215 and the damper 216.

[0091] It is also possible to attach the output detection device 210 to the laser head 90. However, in this case, the weight of the laser head 90 increases and operability decreases, so it is preferable to attach the output detection device 210 to the processing table 200 as shown in this embodiment.

[0092] (Other embodiments) The components shown in the first and second embodiments and the first modification may be appropriately combined to form a new embodiment. For example, the output detection device 210 shown in the second embodiment may be attached to the laser processing device 100 shown in the first embodiment or the modification. In this way, the module laser light LB emitted by each of the laser light sources 12 may be M The actual output of the module laser beam LB and the actual output of the combined laser beam LB irradiated onto the workpiece W can be measured. M Alternatively, it is possible to determine whether or not there is a defect in an optical component through which the coupled laser light LB passes.

[0093] In addition, in the first and second embodiments and the first modification, the laser oscillator 70 is configured to use a plurality of laser modules 10 each having one or a plurality of laser light sources 12, but the present invention is not particularly limited to this. For example, the laser oscillator 70 may have a single laser module 10. Also, the laser oscillator 70 may have only a laser light source 12 that emits a single laser beam. Also, the module laser beam LB M Alternatively, the partial reflection mirror 13 or the partial reflection mirror 215 is used to make a part of the coupled laser beam LB incident on the photodetector 14 or the photodetector 214, but the present invention is not limited to this. For example, a prism or a diffraction grating with a defined diffraction efficiency may be used.

[0094] That is, the present specification discloses a laser oscillator 70 having the following configuration.

[0095] The laser oscillator 70 includes at least a laser light source that emits laser light, a light branching member that branches a portion of the laser light, and a photodetector that receives the portion of the laser light branched by the light branching member and outputs an electrical signal.

[0096] The laser oscillator 70 also includes a movable mirror that is movably provided so as to be positioned on and off the optical path of the laser light, and a light receiving unit that is disposed at a position farther away from the laser light source than the movable mirror. The laser oscillator 70 also includes a control unit that calculates the output of the laser light based on the magnitude of the electrical signal output by the photodetector.

[0097] When the difference between the output value of the laser light calculated by the control unit and the target value exceeds a predetermined range, the control unit moves the movable mirror onto or off the optical path of the laser light to cause the remaining part of the laser light to be incident on the light receiving unit, and at the same time controls the laser light source so that the difference falls within the predetermined range.

[0098] Moreover, it can be said that the present specification discloses a laser processing apparatus 100 having the following configuration.

[0099] The laser processing apparatus 100 includes at least a laser oscillator 70, an optical fiber 80 that guides the laser light emitted from the laser oscillator 70, and a laser head 90 that receives the laser light guided by the optical fiber 80 and irradiates it toward the workpiece W.

[0100] Depending on the laser processing conditions, the surface of the workpiece W may be irradiated with the laser light while scanning it two-dimensionally. In such a case, an optical scanning component such as a galvanometer mirror may be provided inside the laser head 90. This galvanometer mirror may be used as a movable mirror located outside and on the optical path of the combined laser light LB or the laser light. For example, in the second embodiment, a galvanometer mirror may be provided inside the laser head 90, and when measuring the output of the combined laser light LB, the galvanometer mirror may direct the combined laser light LB to a damper provided inside the head. In this case, a partial reflection mirror 13 and a photodetector 14 may be provided inside the second housing 11 of the laser module 10, and a partial reflection mirror 13 and a photodetector 14 may be provided inside the second housing 11 of the laser module 10 to detect the module laser light LB. M The output of the [Industrial Applicability]

[0101] INDUSTRIAL APPLICABILITY The laser oscillator of the present disclosure is small and has a simple configuration, and is capable of measuring and correcting the output of laser light, and is useful when applied to a laser processing device. [Explanation of symbols]

[0102] 10 Laser module 11 Second cabinet 12 Laser light source 13 Partially reflecting mirror (light branching component) 14 Photodetector 15 Movable mirror 16 Damper (light receiving part) 20 Beam combiner 21 3rd cabinet 21a Light entrance 21b Light exit port 22 Mirror No. 1 23 Second mirror (movable mirror) 24 Damper (light receiving part) 30 Condenser optical unit 31 4th cabinet 31a Light entrance 31b Light exit port 32 First focusing lens 40 1st cabinet 50 Control section 51 Storage section 52 Arithmetic section 53 Display section 60 power supply 70 Laser Oscillator 80 Optical Fiber 90 Laser Head 91 5th cabinet 91a Light entrance 91b Light exit port 92 Collimating Lens 93 Second focusing lens 100 Laser processing equipment 200 Processing table 210 Output detection device 211 Post 212 First Arm 213 Second Arm 214 Photodetector 215 Partially reflecting mirror (movable mirror, light branching component) 216 Damper (light receiving part) 300 Processing Area

Claims

1. A laser light source that emits laser light; a light branching member that branches a part of the laser light; a photodetector that receives a part of the laser light branched by the optical branching member and outputs an electrical signal; a movable mirror movably provided so as to be positioned on and off the optical path of the laser light; a light receiving unit disposed at a position farther from the laser light source than the movable mirror; a control unit that calculates an output of the laser light based on the magnitude of the electrical signal, When a difference between the output value of the laser light calculated by the control unit and a target value set in the control unit exceeds a predetermined range, The control unit moves the movable mirror onto or off the optical path of the laser light to cause the remaining part of the laser light to be incident on the light receiving unit, and controls the laser light source so that the difference is within the predetermined range.

2. 2. The laser oscillator according to claim 1, a plurality of second housings are provided, each housing having at least the laser light source, the light branching member, and the light detector disposed therein; the laser beams emitted from the plurality of laser light sources are combined with each other and emitted from the laser oscillator as a single combined laser beam; The control unit calculates an output of the combined laser light based on a sum of the magnitudes of the electrical signals respectively output from the plurality of photodetectors.

3. 3. The laser oscillator according to claim 2, the laser light source, the light branching member, and the light detector are disposed inside a second housing, 2. A laser oscillator comprising: a first housing; a second housing; a movable mirror; and a light receiving portion, the movable mirror and the light receiving portion being disposed inside a third housing connected to the second housing.

4. 4. The laser oscillator according to claim 3, the laser light beams emitted from the plurality of laser light sources are combined with each other inside the third housing and are emitted from the laser oscillator as the combined laser light beam; the movable mirror is provided movably so as to be positioned on and off the optical path of the combined laser light, When the difference between the output value of the combined laser light and the target value exceeds a predetermined range, the control unit moves the movable mirror out of the optical path of the combined laser light to cause the remaining part of the combined laser light to be incident on the light receiving unit, and controls each of the plurality of laser light sources so that the difference is within the predetermined range.

5. 3. The laser oscillator according to claim 2, The laser oscillator further comprises the movable mirror and the light receiving section disposed inside the second housing.

6. 6. The laser oscillator according to claim 5, When the difference between the output value of the combined laser light and the target value exceeds a predetermined range, The control unit moves the movable mirror onto the optical path of the laser light to cause the remaining portion of the laser light to be incident on the light receiving unit, and controls each of the multiple laser light sources so that the difference is within the predetermined range.

7. 2. The laser oscillator according to claim 1, A laser oscillator characterized in that the movable mirror is movably arranged so as to be positioned on an optical path of the laser light other than the optical path toward the photodetector and outside the other optical path.

8. The laser oscillator according to claim 1 ; an optical fiber that guides the laser light emitted from the laser oscillator; a laser head that receives the laser light guided by the optical fiber and irradiates the laser light toward a workpiece.

9. 9. The laser processing apparatus according to claim 8, Further comprising a processing table for supporting the workpiece, the movable mirror is integrated with the light branching member, The light receiving unit is disposed between the laser head and the processing table, the movable mirror is disposed between the laser head and the processing table, at a position at the same height as the light receiving unit with respect to a surface of the processing table; the photodetector is disposed between the laser head and the processing table and at a position closer to the processing table than the movable mirror is, When the difference between the output value of the laser light calculated by the control unit and the target value exceeds a predetermined range, The control unit moves the movable mirror onto the optical path of the laser light to cause a portion of the laser light to be incident on the photodetector and the remainder to be incident on the light receiving unit, and controls the laser light source so that the difference is within the predetermined range.

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