JP7199256B2 - Pass/Fail Judgment Method for Output Measurement Units - Google Patents

Description

The present invention relates to a pass/fail judgment method for an output measuring unit mounted in a laser processing apparatus.

A laser processing apparatus equipped with a laser oscillator is used to process a semiconductor wafer or the like. Since laser processing equipment must control the energy of the laser beam that irradiates the wafer, it is common to have an output measuring unit such as a power meter to measure the output of the laser beam ( For example, see Patent Document 1 and Patent Document 2).

JP 2009-291818 A Japanese Patent Application Laid-Open No. 2008-114228

However, in the output measurement units disclosed in Patent Documents 1 and 2, if the light receiving surface is irradiated with the laser beam for a long time, the irradiated portion of the light receiving surface will burn, and accurate output measurement cannot be performed. There is If the wafer is processed in this state, the wafer will be processed with an incorrect laser output, and the desired processing result cannot be obtained.

If the irradiated part of the light receiving surface is burned in this way, it is necessary to remove the output measurement unit from the laser processing device and compare it with a power meter for calibration in order to check the accuracy of the output measurement unit. There was a problem that it took time and effort.

The present invention has been made in view of the above problems, and aims to provide a pass/fail determination method for an output measuring unit that can reduce the time and effort required to confirm the accuracy of a laser beam output measuring unit. aim.

In order to solve the above-described problems and achieve the object, a pass/fail judgment method for an output measuring unit according to the present invention includes a laser beam irradiation unit including a laser beam oscillator for oscillating a laser beam for processing a workpiece; Laser processing comprising: an output measuring unit having a light receiving surface for measuring the output of the laser beam oscillated from the laser beam oscillator; and moving means for relatively moving the output measuring unit and the laser beam irradiation unit. In an apparatus, a pass/fail judgment method for judging pass/fail of the output measuring unit, comprising: a center output measuring step of positioning the laser beam at the center of the light receiving surface of the output measuring unit and irradiating it to measure the output; a reference output measurement step of moving the beam and the output measurement unit relative to each other to position and irradiate the laser beam on an area other than the center of the light receiving surface of the output measurement unit to measure the output; and the central output measurement step. and a pass/fail judgment step of judging pass/fail of the output measurement unit based on whether the difference in the output of the laser beam measured in the reference output measurement step is within an allowable range.

The acceptance/rejection determination method for the output measuring unit may further include a notification step in which the laser processing apparatus issues a warning when the difference in the output of the laser beam is out of the allowable range.

Advantageous Effects of Invention The present invention has the effect of reducing the time and effort required to confirm the accuracy of a laser beam output measuring unit.

FIG. 1 is a perspective view showing a configuration example of a laser processing apparatus that implements a pass/fail judgment method for an output measuring unit according to a first embodiment. 2 is a perspective view of a workpiece to be processed by the laser processing apparatus shown in FIG. 1. FIG. 3 is a plan view of an output measuring unit of the laser processing apparatus shown in FIG. 1. FIG. FIG. 4 is a flow chart showing the flow of the pass/fail judgment method for the output measuring unit according to the first embodiment. 5 is a side view schematically showing a center output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG. 6 is a plan view showing a region of the light-receiving surface irradiated with a laser beam in the center output measurement step and the reference output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG. 7 is a side view schematically showing a reference output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG. FIG. 8 is a diagram showing an example of information stored in the storage device at the time of judgment in the pass/fail judgment step of the pass/fail judgment method for the output measuring unit shown in FIG. 4 .

A form (embodiment) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. In addition, the components described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the configurations described below can be combined as appropriate. In addition, various omissions, substitutions, or changes in configuration can be made without departing from the gist of the present invention.

[Embodiment 1]
A pass/fail determination method for the output measuring unit according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a configuration example of a laser processing apparatus that implements a pass/fail judgment method for an output measuring unit according to a first embodiment. 2 is a perspective view of a workpiece to be processed by the laser processing apparatus shown in FIG. 1. FIG. 3 is a plan view of an output measuring unit of the laser processing apparatus shown in FIG. 1. FIG. FIG. 4 is a flow chart showing the flow of the pass/fail judgment method for the output measuring unit according to the first embodiment.

The acceptance/rejection determination method for the output measuring unit according to the first embodiment is performed by the laser processing apparatus 1 shown in FIG. The laser processing apparatus 1 is an apparatus for laser processing the workpiece 200 by irradiating a pulsed laser beam 21 to the workpiece 200 shown in FIG. A workpiece 200 to be processed by the laser processing apparatus 1 shown in FIG. 1 is a disk-shaped semiconductor wafer or optical device wafer having a substrate 201 made of silicon, sapphire, gallium arsenide, or the like.

As shown in FIG. 2, the workpiece 200 has dividing lines 203 set in a lattice pattern on the surface 202 of the substrate 201, and devices 204 formed in areas partitioned by the dividing lines 203. doing. The device 204 is, for example, an integrated circuit such as an IC (Integrated Circuit) or LSI (Large Scale Integration), a CCD (Charge Coupled Device), or an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor).

In the first embodiment, the workpiece 200 has an annular frame 210 attached thereto, and a tape 211 having a larger diameter than the outer diameter of the workpiece 200 is attached to the back surface 205 behind the front surface 202 . is supported within the opening 207 of the . In Embodiment 1, the workpiece 200 is split into individual devices 204 along splitting lines 203 .

As shown in FIG. 1, the laser processing apparatus 1 includes a chuck table 10 that holds a workpiece 200 on a holding surface 11, a laser beam irradiation unit 20, an output measuring unit 30, and a moving unit 40 that is moving means. , an imaging unit 90 and a control unit 100 .

The chuck table 10 holds the workpiece 200 on the holding surface 11 . The holding surface 11 is disk-shaped and made of porous ceramic or the like, and is connected to a vacuum suction source (not shown) via a vacuum suction path (not shown). The chuck table 10 sucks and holds the workpiece 200 placed on the holding surface 11 . In Embodiment 1, the holding surface 11 is a plane parallel to the horizontal direction. A plurality of clamping units 12 are arranged around the chuck table 10 to clamp an annular frame 210 that supports the workpiece 200 in the opening 207 . Also, the chuck table 10 is rotated around an axis parallel to the Z-axis direction by the rotation unit 13 . The rotating unit 13 and the chuck table 10 are moved in the X-axis direction by the X-axis moving unit 50 of the moving unit 40 .

The laser beam irradiation unit 20 is a unit that irradiates a pulsed laser beam 21 onto the workpiece 200 held on the chuck table 10 . The laser beam irradiation unit 20 includes a laser beam oscillator 22 that oscillates a laser beam 21 for processing a workpiece 200, and a workpiece that is held on the holding surface 11 of the chuck table 10 with the laser beam 21 oscillated by the laser beam oscillator 22. A mirror 23 that reflects toward the workpiece 200, a condenser lens 24 that converges the laser beam 21 reflected by the mirror 23 onto the workpiece 200, and a converging point 21-1 of the laser beam 21 (see FIG. 5). ) in the Z-axis direction. The laser beam 21 emitted by the laser beam irradiation unit 20 may have a wavelength that is transparent to the workpiece 200 or a wavelength that is absorbent to the workpiece 200 .

The output measuring unit 30 has a light receiving surface 31 for measuring the output of the laser beam 21 oscillated from the laser beam oscillator 22 . The output measurement unit 30 can apply a laser power meter having a sensor that outputs a signal corresponding to the intensity of the laser beam 21 incident on the light receiving surface 31 shown in FIG. 3 to the control unit 100 . In Embodiment 1, the planar shape of the light receiving surface 31 is circular, but in the present invention, the planar shape of the light receiving surface 31 is not limited to circular.

The output measuring unit 30 is arranged, for example, so that the light receiving surface 31 is at the same height as the surface 202 of the workpiece 200 held on the chuck table 10, and the light receiving surface 31 is irradiated with the laser beam 21. As a result, a signal corresponding to the output of the laser beam 21 is output to the control unit 100 so that the output of the laser beam 21 at the processing point on the surface 202 of the workpiece 200 can be measured. In Embodiment 1, the output measuring unit 30 is provided movably together with the chuck table 10, but the present invention is not limited to this, and the output measuring unit 30 is independent of the chuck table 10. may be installed. Also, the position and shape of the light receiving surface 31 are not particularly limited to those described in the first embodiment, and can be appropriately set within a range where the output of the laser beam 21 at the processing point can be measured.

The moving unit 40 relatively moves the chuck table 10 and the output measuring unit 30 and the laser beam irradiation unit 20 . The moving unit 40 moves the chuck table 10 and the output measuring unit 30 as well as the X-axis moving unit 50, which is a processing feed means for moving the chuck table 10 and the output measuring unit 30 in the X-axis direction parallel to the holding surface 11. A Y-axis moving unit 60, which is an indexing means for moving in the Y-axis direction parallel to the holding surface 11 and orthogonal to the X-axis direction, and a Z-axis orthogonal to the holding surface 11 for the laser beam irradiation unit 20. and a Z-axis movement unit 70 for moving in the direction.

In Embodiment 1, the X-axis movement unit 50 and the Y-axis movement unit 60 are installed on the device body 2 of the laser processing device 1 . The X-axis movement unit 50 and the Y-axis movement unit 60 support a movement plate 14 that supports a rotation unit 13 that rotates the chuck table 10 around an axis parallel to the Z-axis direction so as to be movable in the X-axis direction. In addition, it is supported so as to be movable in the Y-axis direction. Further, in Embodiment 1, the output measuring unit 30 is installed on the moving plate 14 .

The Z-axis moving unit 70 is installed on a pillar 3 erected from the apparatus main body 2, and supports the laser beam irradiation unit 20 so as to be movable in the Z-axis direction. The X-axis moving unit 50, the Y-axis moving unit 60, and the Z-axis moving unit 70 rotate around the axis of well-known ball screws 51, 61, 71 and ball screws 51, 61, 71 that are rotatably provided around the axis. Known pulse motors 52, 62, 72 for rotating the moving plate 14 or the laser beam irradiation unit 20 in the X-axis direction, the Y-axis direction, or the Z-axis direction. Prepare.

The laser processing apparatus 1 also includes an X-axis position detection unit (not shown) for detecting the position of the chuck table 10 in the X-axis direction, and a Y-axis direction detection unit (not shown) for detecting the position of the chuck table 10 in the Y-axis direction. A position detection unit and a Z-axis direction position detection unit for detecting the position of the laser beam irradiation unit 20 in the Z-axis direction are provided. Each position detection unit outputs a detection result to the control unit 100 .

The imaging unit 90 is for imaging the workpiece 200 held on the chuck table 10 . The imaging unit 90 is composed of a CCD (Charge Coupled Device) camera or an infrared camera that images the workpiece 200 held on the chuck table 10 . In Embodiment 1, the imaging unit 90 is fixed to the laser beam irradiation unit 20 . The imaging unit 90 captures an image of the workpiece 200 to obtain an image for performing alignment for aligning the workpiece 200 and the laser beam irradiation unit, and outputs the obtained image to the control unit 100. .

The control unit 100 controls the above-described components of the laser processing apparatus 1 to cause the laser processing apparatus 1 to perform processing operations on the workpiece 200 . Note that the control unit 100 includes an arithmetic processing unit having a microprocessor such as a CPU (central processing unit), a storage device having a memory such as ROM (read only memory) or RAM (random access memory), and an input/output unit. A computer having an interface device. The arithmetic processing unit of the control unit 100 performs arithmetic processing according to a computer program stored in the storage device, and outputs a control signal for controlling the laser processing apparatus 1 to the laser processing apparatus 1 via the input/output interface device. The functions of the control unit 100 are implemented by outputting to the components described above.

The control unit 100 also includes a display unit (not shown) configured by a liquid crystal display device for displaying the state of the machining operation, an image, etc., an input unit (not shown) used by the operator to register machining content information, and a notification unit. Unit 101 is connected. The input unit is composed of at least one of a touch panel provided on the display unit and an external input device such as a keyboard. The notification unit 101 is controlled by the control unit 100 and emits at least one of sound and light to notify the operator of the laser processing apparatus 1 .

In addition, the laser processing apparatus 1 uses the output measurement unit 30 to measure the laser beam irradiation unit 20 using the output measurement unit 30 at a predetermined timing set in advance during the processing operation or during the processing operation or at a timing set by the operator's operation on the input unit. The output of the laser beam 21 oscillated by the laser beam oscillator 22 is measured. In the first embodiment, the control unit 100 measures the output of the laser beam 21 emitted by the laser beam oscillator 22 of the laser beam irradiation unit 20 using the output measurement unit 30 before, during or after the processing operation. , the laser beam 21 oscillated by the laser beam oscillator 22 of the laser beam irradiation unit 20 is irradiated onto the area 32 including the center of the light receiving surface 31 of the output measurement unit 30, which is the measurement position.

In the first embodiment, the control unit 100 measures the output of the laser beam 21 emitted by the laser beam oscillator 22 of the laser beam irradiation unit 20 using the output measurement unit 30 before, during or after the processing operation. , controls the focal point position adjusting means to adjust the position of the focal point 21-1 to a position where the distance from the light receiving surface 31 is a predetermined distance 300, as shown in FIG. In addition, in the present invention, in addition to controlling the position of the condensing point 21-1 by controlling the condensing point position adjusting means, the light receiving surface 31 of the output measuring unit 30 is set to a height different from the surface height of the workpiece 200. may be configured to position the device. The control unit 100 calculates the output of the laser beam 21 from the signal according to the intensity of the laser beam 21 oscillated by the laser beam oscillator 22 of the laser beam irradiation unit 20 from the output measurement unit 30 . If the difference between the output of the laser beam 21 oscillated by the laser beam oscillator 22 of the laser beam irradiation unit 20 and the output set by the processing content information or the like is outside the range of a predetermined allowable value, the control unit 100 The notification unit 101 is operated to notify the operator.

Further, the control unit 100 includes a measurement position output measurement section 110, a reference output measurement section 111, and a pass/fail determination section 112, as shown in FIG. When performing the pass/fail determination method of the output measurement unit 30 according to the first embodiment, the measurement position output measurement unit 110 irradiates the laser beam 21 on the light receiving surface 31 of the output measurement unit 30 in the area 32 including the center of the output measurement. , and the output of the laser beam 21 is measured.

The reference output measuring unit 111 irradiates the laser beam 21 on the outer peripheral area 33, which is an area other than the center of the light receiving surface 31 of the output measuring unit 30, i.e., the area other than the measurement position, and measures the output of the laser beam 21. be. The pass/fail judgment unit 112 judges pass/fail of the output measurement unit 30 based on whether the difference in the output of the laser beam 21 measured by the measurement position output measurement unit 110 and the reference output measurement unit 111 is within the allowable range. is. The pass/fail judging section 112 judges that the output measuring unit 30 is acceptable if the difference in the output of the laser beam 21 is within the range of the allowable value, and if the difference in the output of the laser beam 21 is outside the range of the allowable value. It is determined that the output measurement unit 30 is rejected.

The functions of the measurement position output measurement unit 110, the reference output measurement unit 111, and the pass/fail determination unit 112 are realized by the arithmetic processing unit executing a computer program stored in the storage device.

Next, a pass/fail determination method for the output measuring unit according to the first embodiment will be described. The output measurement unit 30 receives the laser beam 21 by irradiating the measurement position (the region 32 including the center in the first embodiment) of the light receiving surface 31 before, after or during the processing operation of the laser processing apparatus 1. The measurement location on surface 31 may burn and the power of laser beam 21 may not be measured accurately. That is, the output measurement unit 30 requires periodical confirmation of the measurement accuracy, etc., because the measurement results fluctuate due to aging and the like. The pass/fail determination method of the output measuring unit according to the first embodiment determines whether or not the output measuring unit 30 of the laser processing apparatus 1 can accurately measure the output of the laser beam 21 at the measurement position of the light receiving surface 31, and outputs This is a method for judging whether the measurement unit 30 is acceptable.

The pass/fail judgment method of the output measuring unit is that if the output measuring unit 30 of the laser processing apparatus 1 determines that the output of the laser beam 21 can be accurately measured at the measurement position of the light receiving surface 31, the output measuring unit is judged to be pass (accepted). However, if it is determined that the output measuring unit 30 of the laser processing apparatus 1 cannot accurately measure the output of the laser beam 21 at the measurement position of the light receiving surface 31, it is determined that the output measuring unit has failed (failed).

The pass/fail determination method for the output measuring unit according to the first embodiment is performed at a timing set by an operator's operation on the input unit, for example, after turning on the power to the laser processing apparatus 1 and ending idling. However, in the present invention, the timing at which the pass/fail determination method for the output measuring unit is performed is not limited to this. As shown in FIG. 4, the pass/fail judgment method for the output measurement unit according to the first embodiment includes a central output measurement step ST1, a reference output measurement step ST2, a pass/fail judgment step ST3, and a notification step ST4.

(Center output measurement step)
5 is a side view schematically showing a center output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG. 6 is a plan view showing a region of the light-receiving surface irradiated with a laser beam in the center output measurement step and the reference output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG.

In the center output measurement step ST1, the measurement position output measurement unit 110 positions and irradiates the laser beam 21 on the area 32 including the center, which is the measurement position irradiated at the time of output measurement of the light receiving surface 31 of the output measurement unit 30, and irradiates the laser beam. 21 is the step of measuring the output of . In the center output measurement step ST1, the measurement position output measurement section 110 controls the X-axis movement unit 50 and the Y-axis movement unit 60 to shift the center of the light receiving surface 31 and the condenser lens 24 of the laser beam irradiation unit 20 to Z positioned in axially opposite positions. In the center output measurement step ST1, the measurement position output measurement unit 110 controls the focusing point position adjusting means to focus the light at a position where the distance from the light receiving surface 31 is a predetermined distance 300 as shown in FIG. By adjusting the position of the point 21-1, the laser beam 21 from the laser beam irradiation unit 20 is irradiated onto the area 32 (shown in FIG. 6) including the center of the light receiving surface 31. FIG.

In the center output measurement step ST1, the measurement position output measurement unit 110 receives a signal corresponding to the intensity of the laser beam 21 emitted by the laser beam oscillator 22 of the laser beam irradiation unit 20 from the output measurement unit 30, and measures the light receiving surface 31. is calculated and stored in a storage device. In Embodiment 1, the measurement position output measurement unit 110 receives a signal corresponding to the intensity of the laser beam 21 and stores the output of the laser beam 21 in the storage device in association with the date. In FIG. 6, the area 32 including the center of the light receiving surface 31 irradiated with the laser beam 21 in the center output measurement step ST1 is indicated by a solid circle. For the pass/fail determination method of the output measurement unit, the measurement position output measurement unit 110 stores the output of the laser beam 21 received in the area 32 including the center of the light receiving surface 31 (hereinafter referred to as the center output) in the storage device. Proceed to output measurement step ST2.

(Reference output measurement step)
7 is a side view schematically showing a reference output measurement step of the pass/fail judgment method for the output measurement unit shown in FIG. 4. FIG. In the reference output measurement step ST2, after the measurement position output measurement unit 110 stores the center output in the storage device, the reference output measurement unit 111 compares the chuck table 10 with the laser beam irradiation unit 20 that irradiates the laser beam 21. , the laser beam 21 is positioned and irradiated on the outer peripheral area 33, which is an area other than the area 32 including the center of the light receiving surface 31 of the output measurement unit 30, that is, the area other than the measurement position, and the output of the laser beam 21 is measured. It is a step to

In the reference output measurement step ST2, the reference output measurement section 111 controls the X-axis movement unit 50 and the Y-axis movement unit 60 to measure the area 32 including the center of the condenser lens 24 and the light receiving surface 31 of the laser beam irradiation unit 20. A region 33 of the outer peripheral portion, which is a region other than the above, is positioned at a position facing in the Z-axis direction. In the reference output measurement step ST2, the reference output measurement unit 111 controls the focal point position adjusting means, and as shown in FIG. After adjusting the position of 21-1, the laser beam 21 from the laser beam irradiation unit 20 is irradiated onto the outer peripheral region 33 of the light receiving surface 31. FIG.

In the reference output measurement step ST2, the reference output measurement unit 111 receives a signal corresponding to the intensity of the laser beam 21 oscillated by the laser beam oscillator 22 of the laser beam irradiation unit 20 from the output measurement unit 30, and measures the intensity of the laser beam 21. The output is calculated and stored in memory. In the first embodiment, the reference output measurement unit 111 receives a signal corresponding to the intensity of the laser beam 21 received in the outer peripheral region 33 of the light receiving surface 31, and the date and measurement position output measurement unit 110 stores the signal. The output of the laser beam 21 received by the outer peripheral region 33 of the light receiving surface 31 (hereinafter referred to as reference output) is stored in a storage device in association with the center output.

As shown by solid lines in FIG. 5, in the reference output measurement step ST2, the laser beam 21 is applied to each of the four outer peripheral regions 33 around the region 32 irradiated with the laser beam 21 in the central output measurement step ST1. Then, the reference output received in each area 33 is stored in association with the date and central output. In this specification, reference output 1, reference output 2, reference output 3, and reference output 4 are used when the reference outputs are distinguished from each other, and they are simply referred to as reference outputs when they are not distinguished. A reference output 1, a reference output 2, a reference output 3, and a reference output 4 indicate outputs of the laser beam 21 received in the outer peripheral region 33 at different positions. After the reference output measurement unit 111 stores the reference output in the storage device, the process proceeds to pass/fail determination step ST3. Further, in the present invention, the number of outer peripheral regions 33 irradiated with the laser beam 21 in the reference output measurement step ST2 is not limited to four, as long as the number is plural.

Further, in the first embodiment, the distance between the condensing point 21-1 and the light receiving surface 31 is set to the predetermined distance 300 in the central output measuring step ST1 and the reference output measuring step ST2 because the light receiving surface of the output measuring unit 30 This is because if the laser beam 21 is received by the laser beam 21 in a condensed state, the light receiving surface 31 will be burned immediately.

(pass/fail judgment step)
FIG. 8 is a diagram showing an example of information stored in the storage device at the time of judgment in the pass/fail judgment step of the pass/fail judgment method for the output measuring unit shown in FIG. 4 . The pass/fail judgment step ST3 is a step for judging pass/fail of the output measurement unit 30 based on whether the difference in the output of the laser beam 21 measured in the central output measurement step ST1 and the reference output measurement step ST2 is within the allowable range. be.

In the first embodiment, the information 400 shown in FIG. 8 is already stored in the storage device of the control unit 100 in the acceptance/rejection determination step ST3. Information 400 shown in FIG. 8 associates the date on which the pass/fail judgment method for the output measuring unit was performed with the central output, reference output 1, reference output 2, reference output 3, and reference output 4. FIG.

In the first embodiment, in the acceptance/rejection determination step ST3, the acceptance/rejection determination unit 112 calculates the average value of the reference output 1, the reference output 2, the reference output 3, and the reference output 4, and calculates the average value, which is the difference in the output of the laser beam 21. and the center output. In the first embodiment, in pass/fail judgment step ST3, if the ratio of the difference between the average value and the central output to the average value is equal to or less than a predetermined percentage, the difference between the average value and the central output is set to the allowable value. is within the range, the output measuring unit 30 is determined to be accepted, and if the predetermined percentage is exceeded, it is determined to be outside the allowable range, and the output measuring unit 30 is determined to be rejected.

In the first embodiment, in the pass/fail judgment step ST3, the judgment result of the pass/fail judgment section 112 (pass or fail of the output measurement unit 30) is dated, center output, reference output 1, reference output 2, reference output 3, and reference output. 4 and stored in the storage device. In the example shown in FIG. 8, the predetermined percentage is set to 4%, each output on A month and B is associated with the judgment result, each output on C month and D is associated with the judgment result, and on A month and B day, the pass is made. , and C month and D day are determined to be unsuccessful. In the present invention, the predetermined percentage is determined, for example, by setting the measurement error caused by the installation of the output measurement unit 30 to 2% and considering the accuracy of the laser beam irradiation unit 20, for example, 3% or more and 5% Below is also acceptable.

The pass/fail judgment method of the output measuring unit ends when pass/fail judgment section 112 judges pass/fail in pass/fail judgment step ST3.

(Notification step)
In the notification step ST4, if the acceptance/rejection determination unit 112 determines in the acceptance/rejection determination step ST3 that the difference between the average value of the output of the laser beam 21 and the center output is outside the allowable range, laser processing is performed. This is the step in which the device 1 issues a warning. In the notification step ST4, when the control unit 100 of the laser processing apparatus 1 determines that the difference between the average value and the center output is outside the allowable range by the pass/fail determination unit 112, the notification unit 101 is operated to Alert the operator. The acceptance/rejection determination method of the output measurement unit ends when the notification unit 101 notifies the operator in notification step ST4.

As described above, the pass/fail determination method of the output measuring unit according to the first embodiment is based on the central output measured in the area 32 including the center of the light receiving surface 31 of the output measuring unit 30 and the area other than the center of the light receiving surface 31. The reference outputs measured in the peripheral area 33 are compared and the output measuring unit 30 is judged to pass or fail depending on whether the difference between them is within an acceptable range. For this reason, the acceptance/rejection determination method for the output measuring unit according to the first embodiment determines whether or not the output measuring unit 30 can accurately measure the output of the laser beam 21 without removing the output measuring unit 30 from the laser processing apparatus 1. Since it is possible for the user of the laser processing apparatus 1 to easily make a judgment, the time and effort required to check the accuracy of the output measurement unit 30 of the laser beam 21 can be reduced, and the number of man-hours can be reduced. There is an effect that it can contribute to

Also, in the pass/fail judgment method of the output measurement unit according to the first embodiment, the center output and the reference output are compared, and the pass/fail of the output measurement unit 30 is judged based on whether the difference between them is within the allowable range. Even if the light-receiving surface 31 is burnt, the replacement of the output measuring unit 30, which itself can accurately measure the output of the laser beam 21, with a new one can be suppressed.

It should be noted that the present invention is not limited to the above embodiments. That is, various modifications can be made without departing from the gist of the present invention. For example, in the present invention, it is not desirable to wash the light-receiving surface 31 of the output measuring unit 30. Therefore, when the output of the laser beam 21 is measured by the output measuring unit 30, the light-receiving surface 31 is dusty. Assuming such a case, the pressurized gas may be sprayed or the gas on the light receiving surface 31 may be sucked before the measurement. Further, according to the present invention, the order of the center output measurement step ST1 and the reference output measurement step ST2 may be reversed from that of the first embodiment, that is, the center output measurement step ST1 may be performed after the reference output measurement step ST2. Also good.

1 laser processing device 20 laser beam irradiation unit 21 laser beam 21-1 focal point 22 laser beam oscillator 30 output measurement unit 31 light receiving surface 33 area (area other than the center)
40 mobile unit (means of transportation)
200 Workpiece ST1 Center output measurement step ST2 Reference output measurement step ST3 Pass/fail judgment step ST4 Notification step

Claims (2)

a laser beam irradiation unit including a laser beam oscillator that oscillates a laser beam for processing a workpiece;
an output measuring unit having a light receiving surface for measuring the output of the laser beam oscillated from the laser beam oscillator;
In a laser processing apparatus having a moving means for relatively moving the output measuring unit and the laser beam irradiation unit,
A pass/fail judgment method for judging pass/fail of the output measurement unit,
a center output measurement step of positioning and irradiating the laser beam at the center of the light receiving surface of the output measurement unit and measuring the output;
a reference output measurement step of moving the laser beam and the output measurement unit relative to each other, irradiating the laser beam on a region other than the center of the light receiving surface of the output measurement unit, and measuring the output;
a pass/fail judgment step for judging pass/fail of the output measurement unit based on whether the difference in the output of the laser beam measured in the central output measurement step and the reference output measurement step is within a range of allowable values;
A pass/fail judgment method for an output measurement unit, comprising: 2. The pass/fail judgment method for an output measuring unit according to claim 1, further comprising a reporting step of issuing a warning from the laser processing device when the difference in output of the laser beams is out of a permissible range. .

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