KR20220127348A - laser processing equipment - Google Patents

Abstract

The laser processing apparatus 1 has the laser oscillator 4 which outputs the pulse laser beam 5, and galvanometer mirrors 11X, 11Y, The pulse laser beam 5 in the galvanometer mirrors 11X, 11Y. A galvano scanner (13X, 13Y) which deflects the pulsed laser beam 5 by the reflection of and which rotates the galvanometer mirrors 11X, 11Y by control according to the position command 29a, and a galvano scanner ( 13X, 13Y) has an incident region on which the deflected pulsed laser light 5 is incident, the fθ lens 15 is a lens for condensing the pulsed laser light 5 incident on the incident region, and A lens temperature measuring unit 9 that measures the temperature of the lens by detecting infrared rays to obtain lens temperature information, and a galvano command conversion unit 6 that is a correction unit that corrects the position command 29 based on the temperature information. be prepared

Description

laser processing equipment

The present disclosure relates to a laser processing apparatus for processing a workpiece by irradiation of pulsed laser light.

A laser processing apparatus is known which has a processing head equipped with a galvano scanner for deflecting pulsed laser light and an f? lens for condensing pulsed laser light, and for drilling a workpiece such as a printed wiring board. In such a laser processing apparatus, when a pulsed laser beam penetrates an f(theta) lens, a part of a pulsed laser beam may be absorbed by an f(theta) lens, and the temperature of an f(theta) lens may rise. As the temperature of the fθ lens increases, the refractive index of the fθ lens changes. When the refractive index of the f? lens changes, the irradiation position of the pulsed laser beam on the workpiece changes.

Patent Document 1 discloses a laser processing apparatus that measures the temperature of the fθ lens and corrects the irradiation position based on the temperature of the fθ lens. The laser processing apparatus of Patent Document 1 measures the temperature of the fθ lens by using a temperature sensor provided on the side surface of the fθ lens.

Japanese Patent Laid-Open No. 2003-290944

In the case of correcting the irradiation position by the technique of Patent Document 1, in order to enable high-precision correction, it is desired that the temperature of the region where the pulsed laser light is incident among the fθ lenses can be measured instantaneously and accurately. In the conventional laser processing apparatus disclosed in Patent Document 1, since a temperature sensor is provided on the side surface of the fθ lens, the pulsed laser beam is influenced by the temperature around the fθ lens and the delay of heat conduction in the fθ lens. It is difficult to instantaneously and accurately measure the temperature of this incident region. Therefore, according to the prior art, the laser processing apparatus had a problem that the improvement of processing precision was difficult because high-precision correction of an irradiation position was difficult.

The present disclosure has been made in view of the above, and an object of the present disclosure is to obtain a laser processing apparatus capable of improving processing accuracy.

In order to solve the above problems and achieve the object, a laser processing apparatus according to the present disclosure includes a laser oscillator for outputting pulsed laser light and a galvanometer, and pulses by reflection of the pulsed laser light in the galvanometer mirror. A galvano scanner that deflects a laser beam and rotates a galvanometer mirror by control according to a position command, and a pulse laser that has an incident region into which the deflected pulsed laser beam is incident in the galvano scanner, and is incident on the incident region A lens for condensing light, a lens temperature measuring unit for measuring the temperature of the lens by detecting infrared rays emitted from the incident region to obtain lens temperature information, and a correction unit for correcting a position command based on the temperature information.

The laser processing apparatus which concerns on this indication achieves the effect that the improvement of processing precision becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the structure of the laser processing apparatus which concerns on Embodiment 1. FIG.
It is a figure for demonstrating the measurement area|region which is the object of temperature measurement by the lens temperature measuring part in Embodiment 1. FIG.
It is a figure for demonstrating the laser output command in Embodiment 1, a laser output, and a temperature measurement result.
Fig. 4 is a diagram showing the functional configuration of a temperature calculation unit included in the lens temperature measuring unit in the first embodiment.
It is a figure for demonstrating the correction|amendment of the position command by the galvano command conversion part in Embodiment 1. FIG.
6 is a flowchart showing an operation procedure of a control device included in the laser processing apparatus according to the first embodiment.
It is a figure for demonstrating the measurement wavelength of the radiation temperature sensor in Embodiment 2. FIG.
8 is a diagram showing the configuration of the laser processing apparatus according to the second embodiment.
It is a figure for demonstrating the laser output command in Embodiment 2, a laser output, and a temperature measurement result.
10 is a diagram showing the configuration of the laser processing apparatus according to the third embodiment.
Fig. 11 is a diagram showing a plurality of divided regions set in the incident region of the fθ lens in the third embodiment.
12 is a diagram for explaining a measurement area that is a target of temperature measurement by the lens temperature measurement unit in the third embodiment.
It is a figure which shows the example of the hardware structure of the control apparatus which the laser processing apparatus which concerns on Embodiment 1 - 3 has.

EMBODIMENT OF THE INVENTION Below, the laser processing apparatus which concerns on embodiment is demonstrated in detail based on drawing.

Embodiment 1.

1 : is a figure which shows the structure of the laser processing apparatus 1 which concerns on Embodiment 1. As shown in FIG. The laser processing apparatus 1 which concerns on Embodiment 1 drills the to-be-processed object 16 by irradiation of the pulsed laser beam 5. As shown in FIG. The workpiece 16 is a printed wiring board mounted on an electronic device or the like. The to-be-processed object 16 should just be what can become the object of a drilling process, and things other than a printed wiring board may be sufficient as it.

In Embodiment 1, the X axis, the Y axis, and the Z axis are three axes perpendicular to each other. The X-axis and the Y-axis are horizontal axes. The Z axis is an axis in the vertical direction. The laser processing apparatus 1 performs the drilling process which forms the some hole 17 disperse|distributed in an X-axis direction and a Y-axis direction at high speed.

The laser processing apparatus 1 has the laser oscillator 4 which outputs the pulsed laser beam 5. As shown in FIG. The pulsed laser light 5 is infrared light. In Embodiment 1, the laser oscillator 4 is a carbon dioxide (CO ₂ ) laser. The peak wavelength of the pulsed laser beam 5 is a wavelength included in the range of 9.3 micrometers - 10.6 micrometers.

The processing head 26 of the laser processing apparatus 1 includes the galvano scanners 13X and 13Y for deflecting the pulsed laser light 5 and the fθ lens 15 which is a lens for condensing the pulsed laser light 5 . have

The galvanometer scanner 13X has a galvanometer mirror 11X that reflects the pulsed laser light 5 incident on the processing head 26 and a motor 12X that rotates the galvanometer mirror 11X. The galvano scanner 13X deflects the pulsed laser beam 5 by reflection of the pulsed laser beam 5 in the galvanometer mirror 11X. Moreover, the galvanometer scanner 13X rotates the galvanometer mirror 11X by control according to the position command 29a. The galvano scanner 13X moves the irradiation position of the pulsed laser beam 5 to the X-axis direction by rotating the galvanometer mirror 11X within the range of a specific oscillation angle.

The galvano-scanner 13Y has the galvanometer mirror 11Y which reflects the pulsed laser beam 5 which injected from the galvano-scanner 13X, and the motor 12Y which rotationally drives the galvanometer mirror 11Y. The galvano scanner 13Y deflects the pulsed laser beam 5 by reflection of the pulsed laser beam 5 in the galvanometer mirror 11Y. Moreover, the galvanometer scanner 13Y rotates the galvanometer mirror 11Y by control according to the position command 29a. The galvanometer scanner 13Y moves the irradiation position of the pulsed laser beam 5 to the Y-axis direction by rotating the galvanometer mirror 11Y within the range of a specific oscillation angle.

The fθ lens 15 is fixed to the lens frame 14 . The fθ lens 15 concentrates the pulsed laser light 5 reflected by the galvanometer mirror 11Y on the irradiation position of the workpiece 16 . The material of the fθ lens 15 is germanium or zinc selenide.

The laser processing apparatus 1 has a Z-axis table which moves the processing head 26 in the Z-axis direction above the to-be-processed object 16. As shown in FIG. The illustration of the Z-axis table is omitted. When the Z-axis table moves the processing head 26 , the laser processing apparatus 1 focuses the fθ lens 15 on the workpiece 16 .

The laser processing apparatus 1 has an XY table 18 . The XY table 18 has a top table 19 that moves under control according to a position command 27 . The workpiece 16 is placed on a top table 19 . The XY table 18 moves the workpiece 16 together with the top table 19 .

Here, when driving galvano-scanner 13X, 13Y without moving the top table 19 WHEREIN: Let the area|region which can move an irradiation position be a scanning area|region. The scanning area is, for example, an area of 50 mm in the X-axis direction and 50 mm in the Y-axis direction. The top table 19 can move in a wider range than the size of the workpiece 16 . For example, while the size of the workpiece 16 in the X-axis direction and the Y-axis direction is about 300 mm x 300 mm, the top table 19 is 600 mm x in the X-axis direction and the Y-axis direction. It moves in a range of about 600 mm. The laser processing apparatus 1 enables the drilling process which makes the whole to-be-processed object 16 into object by the drive of galvano scanner 13X, 13Y, and movement of the top table 19.

The laser processing apparatus 1 has the control apparatus 25 which controls the laser processing apparatus 1 whole. The control device 25 includes a command generation unit 2 for generating various commands, a laser control unit 3, a galvano command conversion unit 6 serving as a correction unit, a galvano control unit 10, and an XY table control unit ( 20) has.

The instruction|command generating part 2 produces|generates the position instruction|command 27 with respect to the XY table 18, the laser output instruction|command 28, and the position instruction|command 29 with respect to galvano scanner 13X, 13Y. The command generation unit 2 outputs the generated position command 27 to the XY table control unit 20 . The command generation unit 2 outputs the generated laser output command 28 to the laser control unit 3 . The command generation unit 2 outputs the generated position command 29 to the galvano command conversion unit 6 .

The galvano command conversion unit 6 corrects the position command 29 based on the temperature information output from the lens temperature measurement unit 9 . The lens temperature measuring unit 9 will be described later. The galvano command conversion unit 6 outputs the position command 29a. When the galvano command conversion part 6 correct|amends the position command 29, it outputs the position command 29 after correction|amendment as the position command 29a. The galvano command conversion unit 6 outputs the uncorrected position command 29 as the position command 29a, when the position command 29 is not corrected.

The laser control unit 3 controls the laser oscillator 4 according to the laser output command 28 . The laser control unit 3 controls the power of the pulsed laser light 5 , the pulse width of the pulsed laser light 5 , and the timing at which the pulsed laser light 5 is output according to the laser output command 28 .

The galvano control part 10 controls the galvano scanner 13X and the galvano scanner 13Y according to the position command 29a. The galvano control part 10 controls the rotation of the galvanometer mirror 11X by the motor 12X, and determines the position of the galvanometer mirror 11X. The galvanometer control part 10 controls the rotation of the galvanometer mirror 11Y by the motor 12Y, and determines the position of the galvanometer mirror 11Y. The galvano control unit 10 corrects optical distortion characteristics caused by the galvano scanners 13X and 13Y and the fθ lens 15 . The galvano control unit 10 uses a preset distortion correction function to correct the optical distortion characteristics. By correcting the optical distortion characteristic, the galvano scanner 13X accurately moves the pulsed laser beam 5 in the X-axis direction. The galvano scanner 13Y moves the pulsed laser beam 5 precisely in the Y-axis direction. Thereby, the laser processing apparatus 1 can form the hole 17 in the correct position in XY plane.

The XY table control part 20 controls the XY table 18 according to the position command 27 . The XY table control unit 20 controls the movement of the top table 19 by the XY table 18 to position the top table 19 .

The laser processing apparatus 1 has a lens temperature measuring unit 9 that measures the temperature of the fθ lens 15 . The lens temperature measuring unit 9 obtains temperature information indicating the temperature of the fθ lens 15 . When the pulsed laser light 5 passes through the fθ lens 15, a part of the pulsed laser light 5 is absorbed by the fθ lens 15, so that the temperature of the fθ lens 15 rises. When the temperature of the f(theta) lens 15 rises, the irradiation position of the pulsed laser beam 5 in the to-be-processed object 16 changes because the refractive index of the f(theta) lens 15 changes. The laser processing apparatus 1 corrects the irradiation position of the pulsed laser beam 5 in the to-be-processed object 16 by correct|amending the position command 29 based on the measurement result by the lens temperature measuring part 9. do.

The lens temperature measuring unit 9 has a temperature calculating unit 7 and a radiation temperature sensor 8 . The temperature calculator 7 is included in the control device 25 . The temperature calculation unit 7 performs calculations for temperature measurement. The command generation unit 2 outputs the laser output command 28 and the temperature calculation parameter 34 to the temperature calculation unit 7 .

The radiation temperature sensor 8 is a non-contact temperature sensor. The radiation temperature sensor 8 is disposed above the incident region among the fθ lenses 15 . The incident region is a region on the surface of the fθ lens 15 , and is a region where the deflected pulsed laser light 5 in the galvano scanners 13X and 13Y enters. The fθ lens 15 condenses the pulsed laser light 5 incident on the incident region. The radiation temperature sensor 8 measures the temperature of the fθ lens 15 in the incident region by detecting infrared rays radiated from the incident region of the fθ lens 15 .

The temperature of the fθ lens 15 changes in the range of, for example, 25°C to 30°C. In this case, the intensity of infrared rays emitted from the f? lens 15 is strongest at a wavelength of about 10 mu m. In the case of this example, as the radiation temperature sensor 8, an infrared detector having a sensitivity to a wavelength of 8 µm to 12 µm is used. As such an infrared detector, an inexpensive infrared detector such as a thermopile or a thermistor can be used.

In Embodiment 1, the radiation temperature sensor 8 is not limited to having a sensitivity in a wavelength of 8 micrometers - 12 micrometers, What is necessary is just to have a sensitivity in a wavelength range of 9.3 micrometers - 10.6 micrometers. The lens temperature measuring unit 9 has a radiation temperature sensor 8 having a sensitivity in a wavelength range of at least 9.3 μm to 10.6 μm. Since the radiation temperature sensor 8 faces each other in the incident region of the fθ lens 15, the infrared rays emitted from the fθ lens 15 depending on the temperature of the fθ lens 15 and the fθ lens 15 The reflected light 21 , which is the reflected pulsed laser light 5 , is incident on the radiation temperature sensor 8 . The illustration of infrared rays emitted from the fθ lens 15 is omitted.

When the reflected light 21 is incident on the infrared detector, the reflected light 21 affects the measurement result by the infrared detector. That is, the measurement result by the infrared detector becomes a value higher than the actual temperature of the fθ lens 15 . Therefore, in the first embodiment, the lens temperature measuring unit 9 obtains the temperature information from which the influence of the reflected light 21 is removed in the temperature calculating unit 7 . The exclusion of the influence of the reflected light 21 indicates that the increase in the measurement result due to the incident of the reflected light 21 on the radiation temperature sensor 8 is eliminated. The temperature calculation unit 7 outputs the obtained temperature information to the galvano command conversion unit 6 .

2 : is a figure for demonstrating the measurement area|region 23 which is the object of temperature measurement by the lens temperature measuring part 9 in Embodiment 1. As shown in FIG. FIG. 2 shows the fθ lens 15 fixed to the lens frame 14 as viewed from the vertical direction.

The pulsed laser light 5 deflected in the galvano scanners 13X and 13Y enters the incident region 22 of the fθ lens 15 . The measurement area 23 by the radiation temperature sensor 8 is an area within the incident area 22 . The radiation temperature sensor 8 measures the average temperature of the incident region 22 by temperature measurement of the measurement region 23 . The temperature of the fθ lens 15 measured by the lens temperature measuring unit 9 is the average temperature of the incident region 22 .

Next, with reference to FIG. 3 , the operation of the lens temperature measuring unit 9 will be described. 3 : is a figure for demonstrating the laser output command 28 in Embodiment 1, a laser output, and a temperature measurement result.

Fig. 3(a) shows a change in a signal that is a laser output command 28 output from the command generation unit 2 to the laser control unit 3 . FIG. 3B shows a change in the laser output by the laser oscillator 4 , that is, a change in the output of the pulsed laser light 5 . In FIG.3(c), the graph of the solid line shows the output of the radiation temperature sensor 8, ie, the measured value of the radiation temperature sensor 8. As shown in FIG. In Fig. 3(c) , the broken line graph indicates the temperature that can be measured by the radiation temperature sensor 8 when the radiation temperature sensor 8 is not affected by the reflected light 21 . . That is, the graph of the broken line indicates the temperature of the fθ lens 15 to be measured by the radiation temperature sensor 8 . 3D shows temperature information that is output from the lens temperature measurement unit 9 , that is, the measurement result of the lens temperature measurement unit 9 .

In Fig. 3A, the command generation unit 2 generates a laser output command 28 having a peak power of P1 and a pulse width of td, t1, t2, t3, t4, t5, t7, t8. , t9, t10, and t11. During the period from t1 to t12, the period in which the laser output command 28 is on is from t1 to t1+td, t2 to t2+td, t3 to t3+td, t4 to t4+td, t5 to t5+td, and t7 Each period is t7+td, t8 to t8+td, t9 to t9+td, t10 to t10+td, and t11 to t11+td. During the period from t1 to t12, a period other than the on-time period is a period during which the laser output command 28 is turned off. When the laser output command 28 is on, the laser control unit 3 controls the laser oscillator 4 so that the laser output becomes P1. When the laser output command 28 is off, the laser control unit 3 makes the laser output zero.

As shown in FIG.3(b), the laser oscillator 4 outputs the pulsed laser beam 5 equivalent to the laser output command 28. As shown in FIG. In addition, although not shown in FIG. 3, the operation|movement of the laser output by the laser oscillator 4 originates in the dynamic characteristic of the laser oscillator 4, and it is delayed slightly from the laser output command 28. As shown in FIG.

As shown in the graph of the solid line in Fig. 3(c), the output of the radiation temperature sensor 8 varies greatly up and down in the period from t1 to t6, and is different from the temperature indicated by the graph of the broken line. are greatly separated. The output of the radiation temperature sensor 8 is delayed by the measurement time constant of the radiation temperature sensor 8 from the change of the pulsed laser light 5, and changes up and down. When the radiation temperature sensor 8 receives the reflected light 21 together with the infrared rays emitted by the fθ lens 15, from the radiation temperature sensor 8, both the infrared measurement results and the reflected light 21 measurement results are combined. The result is output. Since the ratio of the reflected light 21 is larger than the ratio of infrared rays, a large waveform appears in the graph showing the output of the radiation temperature sensor 8 . Since the output of the radiation temperature sensor 8 is greatly affected by the reflected light 21 , the lens temperature measuring unit 9 uses the measurement result of the radiation temperature sensor 8 as it is the measurement result of the temperature of the fθ lens 15 . can't be done with In addition, the radiation temperature sensor 8 has a measurement time constant on the order of milliseconds. The temperature of the f? lens 15 changes with a time constant that is later than the measurement time constant of the radiation temperature sensor 8 . For this reason, as shown in the graph of the broken line, the change in the temperature of the fθ lens 15 becomes a gradual change.

After the laser output command 28 is output at t5, the laser output command 28 is not output in the period from t5+td to t7. The graph of the solid line shown in Fig. 3C gradually approaches the graph of the broken line after t5+td. That is, the measurement result by the radiation temperature sensor 8 gradually decreases and converges to the temperature of the fθ lens 15 . In the period from t6 to t7, the measurement result by the radiation temperature sensor 8 becomes equal to the temperature of the fθ lens 15. The fact that the measurement result is equal to the temperature of the fθ lens 15 indicates that even if there is a difference between the measurement result and the temperature of the fθ lens 15 , the difference is negligible in the correction of the position command 29 .

In the following description, the period required for the measurement result by the radiation temperature sensor 8 to converge to the temperature of the fθ lens 15 is referred to as a sensor recovery period “twait”. In the above description, the period from t5+td to t6 is the sensor recovery period "twait". When the laser pulse signal does not turn on in the sensor recovery period "twait" from when the laser output command 28 is turned off, the measurement result by the radiation temperature sensor 8 after the lapse of the sensor recovery period "twait" is equal to the temperature of the fθ lens 15 . In the following description, the period in which the measurement result by the radiation temperature sensor 8 becomes equal to the temperature of the fθ lens 15 is referred to as the sensor validity period. In addition, a period other than a sensor validity period is called a sensor invalid period. In the case of the example shown in FIG. 3, each of the period from t1 to t6 and the period from t7 to t12 is a sensor invalidation period. In Fig. 3, each of the period from t1, the period from t6 to t7, and the period from t12 is a sensor validity period.

The temperature calculation unit 7 has a laser output command when the laser output command 28 output from the command generation unit 2 is switched from on to off, and the sensor recovery period “twait”, which is a preset period, elapses. The period until the output of (28) turns on is determined as the sensor valid period. The temperature calculation unit 7 measures the temperature of the fθ lens 15 during the sensor validity period. The temperature calculation part 7 outputs the measurement result by the radiation temperature sensor 8 as temperature information in the sensor validity period.

On the other hand, the temperature calculation unit 7 estimates the temperature information of the fθ lens 15 in the sensor invalid period based on the temperature measured in the sensor valid period. The temperature calculation unit 7 uses parameters such as the output of the radiation temperature sensor 8 immediately before the sensor invalidation period, the laser output command 28, and the time constant of the fθ lens 15, the fθ lens ( 15) to estimate the temperature information. The temperature calculation unit 7 outputs an estimation result of the temperature information of the fθ lens 15 as temperature information in the sensor invalidation period.

Fig. 3(d) shows the measurement result of the temperature of the fθ lens 15 in the sensor valid period and the estimation result of the temperature of the fθ lens 15 in the sensor invalid period. The change in the output of the lens temperature measuring unit 9 shown in Fig. 3D almost coincides with the change in the temperature of the fθ lens 15 shown by the broken line graph in Fig. 3C. In this way, the lens temperature measuring unit 9 can obtain temperature information that can be regarded as the temperature of the fθ lens 15 , and can obtain accurate temperature information of the fθ lens 15 .

Next, the process by the temperature calculation part 7 is demonstrated. 4 is a diagram showing the functional configuration of the temperature calculation unit 7 provided in the lens temperature measurement unit 9 in the first embodiment. The temperature calculation unit 7 includes a sensor state determination unit 30 , a sensor output storage unit 31 , a temperature estimation unit 32 , and a temperature information switching unit 33 . A laser output command 28 , a temperature calculation parameter 34 , and a measurement value that is a measurement result by the radiation temperature sensor 8 are input to the temperature calculation unit 7 .

The temperature calculation parameter 34 is a parameter used in the calculation in the temperature calculation unit 7 . The temperature calculation parameter 34 includes a set value indicating the length of the sensor recovery period "twait". The temperature calculation parameter 34 includes a conversion gain and a thermal time constant of the fθ lens 15 . The conversion gain is an energy-temperature conversion gain for converting the energy of the pulsed laser light 5 into the temperature change amount of the fθ lens 15 .

A laser output command 28 and a temperature calculation parameter 34 are input to the sensor state determination unit 30 . The sensor state determination unit 30 determines the sensor valid period and the sensor invalid period based on the laser output command 28 and the set value of the sensor recovery period "twait". The sensor state determination unit 30 selects a period in which the ON of the laser output command 28 is repeated with an OFF period shorter than the sensor recovery period “twait”, such as the period from t1 to t5+td. considered as invalid. The sensor state determination unit 30, such as the period from t5+td to t6, sets the period from when the laser output command 28 is turned off until the sensor recovery period "twait" elapses as the sensor invalid period. judge The sensor state determination unit 30 determines, as in the period from t6 to t7, the period from the elapse of the sensor recovery period "twait" until the laser output command 28 is turned on as the sensor validity period. do.

The sensor state determination unit 30 outputs a sensor state flag 35 , which is information indicating the determination result, to the sensor output storage unit 31 and the temperature information switching unit 33 . The sensor state determination unit 30 turns on the sensor state flag 35 when it is determined that the present is the sensor invalidation period. The sensor state determination unit 30 turns off the sensor state flag 35 when it is determined that the present is the sensor valid period.

The measured value of the radiation temperature sensor 8 and the sensor state flag 35 are input to the sensor output storage unit 31 . The sensor output storage unit 31 stores the measured value input from the radiation temperature sensor 8 immediately before the sensor invalidation period. The sensor output storage unit 31 outputs the stored corresponding measured value to the temperature estimation unit 32 . Moreover, the sensor output storage part 31 preserve|saves the measured value input from the radiation temperature sensor 8, when the sensor state flag 35 which is off is input. The sensor output storage unit 31 outputs, to the temperature estimation unit 32 , the measured value stored in the sensor valid period when the on-sensor state flag 35 is input.

A laser output command 28 , a temperature calculation parameter 34 , and a sensor state flag 35 are input to the temperature estimation unit 32 . To the temperature estimation unit 32 , the measured value of the radiation temperature sensor 8 is input from the sensor output storage unit 31 . The temperature estimation unit 32 performs calculations for estimating the temperature of the fθ lens 15 in the sensor invalid period.

When the on-sensor state flag 35 is input, the temperature estimation unit 32 multiplies the laser output command 28 by a conversion gain. The temperature estimation unit 32 estimates the amount of change in temperature of the fθ lens 15 by using the multiplication result and the low-pass filter using the thermal time constant of the fθ lens 15 . Moreover, the temperature estimation part 32 adds the measured value of the radiation temperature sensor 8 in just before the sensor invalidation period to the estimation result of the temperature change amount. Thereby, the temperature estimation unit 32 obtains an estimated value of the temperature of the fθ lens 15 in the sensor ineffective period. The temperature estimation unit 32 outputs the calculated estimated value to the temperature information conversion unit 33 .

The temperature estimation unit 32 does not perform calculations for estimating the temperature when the off-sensor state flag 35 is input. The temperature estimation unit 32 reads the measured value of the radiation temperature sensor 8 from the sensor output storage unit 31 during the sensor validity period. The temperature estimation unit 32 clears the state quantity of the low-pass filter so that the calculation result of the estimated value in the sensor invalid period coincides with the measured value in the sensor valid period.

In the temperature information switching unit 33, the estimated value of the temperature of the fθ lens 15 in the sensor invalid period, the measured value of the radiation temperature sensor 8 in the sensor valid period, and the sensor state flag 35 are provided. is input The temperature information switching unit 33 selects an estimated value of the temperature of the fθ lens 15 when the on-sensor state flag 35 is input. The temperature calculation unit 7 outputs the estimated value input from the temperature estimation unit 32 as temperature information during the sensor ineffective period.

On the other hand, the temperature information switching part 33 selects the measured value of the radiation temperature sensor 8, when the sensor state flag 35 which is off is input. The temperature calculation unit 7 outputs the measured value input from the radiation temperature sensor 8 as temperature information during the sensor validity period. In this way, the temperature information output from the temperature calculation unit 7 is converted into an estimated value of the temperature of the fθ lens 15 and a measured value of the radiation temperature sensor 8 by the temperature information conversion unit 33 .

The lens temperature measuring unit 9 outputs the measured value of the radiation temperature sensor 8 as temperature information in the sensor validity period during which the influence of the reflected light 21 is not present. In addition, the lens temperature measuring unit 9 does not use the measured value of the radiation temperature sensor 8 in the sensor invalid period when the effect of the reflected light 21 is large, and the radiation temperature sensor ( 8) is used to estimate the temperature of the fθ lens 15 . The lens temperature measuring unit 9 outputs an estimated value of the temperature of the fθ lens 15 as temperature information in the sensor invalid period. In this way, the lens temperature measuring unit 9 obtains the temperature information from which the influence of the reflected light 21 is removed.

Next, the process by the galvano command conversion part 6 is demonstrated. The position command 29 from the command generation unit 2 and the temperature information from the lens temperature measurement unit 9 are input to the galvano command conversion unit 6 . Here, let the position command 29 with respect to the galvano scanner 13X be Xg(k), and let the position command 29 with respect to the galvano scanner 13Y be Yg(k). k is a machining hole number. The machining hole number is an integer assigned to each of the plurality of holes 17 formed in the to-be-processed object 16 in order from 1 . The temperature information of the fθ lens 15 at time t is θ(t), and the initial temperature, which is the temperature of the fθ lens 15 before processing, is θ0. The galvano command conversion unit 6 calculates ΔXg(k) and ΔYg(k), which are correction amounts based on temperature information, by the procedure shown below. In addition, the calculation method shown in Embodiment 1 is one example, and you may change the calculation method suitably.

With respect to the fθ lens 15, Δθ(t), which is the amount of temperature change from θ0 at time t, is expressed by the following equation (1).

[Equation 1]

…(1)

… (One)

The galvano command conversion part 6 calculates|requires Pg which is a temperature conversion parameter using following Formula (2).

[Equation 2]

…(2)

… (2)

Each of a0, a1, a2, b0, b1, and b2 is a correction coefficient. A correction coefficient is calculated|required beforehand by drilling-processing to test boards, such as an acrylic board, using the laser processing apparatus 1. Based on the amount of deviation between the position of the hole 17 formed in the test board and the command position, and the temperature information of the fθ lens 15 obtained by the lens temperature measuring unit 9 during processing, adjustment is made so that the processing error is minimized. Each correction coefficient obtained is obtained.

The galvano command conversion part 6 calculates|requires (DELTA)Xg(k) and (DELTA)Yg(k) shown by following Formula (3) by using said Formula (2).

[Equation 3]

…(3)

… (3)

The galvano command conversion unit 6 uses the formula (3) and Xg(k) and Yg(k) which are the position commands 29, and Xgout(k) which is the position command 29 after correction based on the temperature. ), Ygout(k) is obtained. Xgout(k) and Ygout(k) are represented by the following formula (4). The galvano command conversion unit 6 outputs Xgout(k) and Ygout(k) as the position command 29a.

[Equation 4]

…(4)

… (4)

5 : is a figure for demonstrating correction of the position command 29 by the galvano command conversion part 6 in Embodiment 1. FIG. Fig. 5(a) shows a state in which the drilling process was performed when the temperature of the fθ lens 15 was θ0. In Fig. 5, a position 40, which is the center of a cross indicated by a broken line, is a machining position indicated by Xg(k) and Yg(k), which are the position commands 29 . In FIG. 5A , the center of the formed hole 17a overlaps the position 40 . There is no deviation between the position command 29 and the hole 17a.

Fig. 5(b) shows a state in which the drilling process was performed when the temperature of the fθ lens 15 is θ(t) higher than θ0. In FIG.5(b), the center of the formed hole 17b turns into a position in the lower-left direction from the position 40. In FIG. A deviation between the position command 29 and the hole 17b has occurred.

Fig. 5 (c) is a state in which the temperature of the fθ lens 15 is θ(t), and after the position command 29 is corrected by the galvano command conversion unit 6, drilling is performed. is indicating The position 41, which is the center of the cross indicated by the broken line, is a machining position indicated by Xgout(k) and Ygout(k). In Fig. 5(c) , the position 41 is moved from the position 40 to the upper right direction in the paper. The center of the formed hole 17c coincides with the position 40 . The galvano command conversion unit 6 corrects the position command 29 by obtaining Xgout(k) and Ygout(k) capable of resolving the shift between the position command 29 and the hole 17c in this way. . The laser processing apparatus 1 can form the hole 17c in the correct position by correct|amending the position command 29 in the galvano command conversion part 6 .

Next, with reference to FIG. 6, the operation|movement of the control apparatus 25 is demonstrated. 6 is a flowchart showing an operation procedure of the control device 25 included in the laser processing device 1 according to the first embodiment.

In step S1 , the control device 25 interprets the machining program by the command generation unit 2 , and transmits initial parameters from the command generation unit 2 to each unit within the control device 25 . The command generation unit 2 transmits the temperature calculation parameter 34 which is an initial parameter to the temperature calculation unit 7 . The command generation unit 2 transmits a correction coefficient that is an initial parameter to the galvano command conversion unit 6 .

In step S2, the control device 25 analyzes the machining program by the command generation unit 2, and the position of the XY table 18 is based on the position information of the machining hole which is the hole 17 to be formed next. The command 27 and the position command 29 of the galvano scanners 13X and 13Y are generated. The command generation unit 2 generates the position command 27 and the position command 29 so that the irradiation position of the pulsed laser beam 5 on the workpiece 16 follows the position information of the processing hole. The command generation unit 2 also corrects a positioning error that is an error in the installation position of the XY table 18 , and also corrects a pitch error of the XY table 18 .

In step S3, the control apparatus 25 positions the to-be-processed object 16 by control of the XY table 18 according to the position command 27 of the XY table 18. As shown in FIG. The command generation unit 2 sends a position command 27 to the XY table control unit 20 . The XY table control part 20 positions the top table 19 of the XY table 18 according to the position instruction|command 27. As shown in FIG. In this way, the control device 25 positions the workpiece 16 placed on the top table 19 .

In step S4 , the control device 25 calculates the temperature of the fθ lens 15 in the lens temperature measuring unit 9 . The command generating unit 2 sends a laser output command 28 to the lens temperature measuring unit 9 . The temperature calculation unit 7 calculates the temperature of the fθ lens 15 based on the laser output command 28 and the measured value of the radiation temperature sensor 8 . The lens temperature measuring unit 9 sends temperature information, which is a calculation result, to the galvano command converting unit 6 .

In step S5, the control apparatus 25 correct|amends the position command 29 of galvano scanner 13X, 13Y based on temperature information. The command generation unit 2 sends the position command 29 to the galvano command conversion unit 6 . Temperature information of the fθ lens 15 is input from the lens temperature measuring unit 9 to the galvano command conversion unit 6 . The galvano command conversion unit 6 corrects the position command 29 based on the temperature information. The galvano command conversion unit 6 sends the corrected position command 29a to the galvano control unit 10 .

In step S6, the control device 25 controls the galvano scanners 13X and 13Y according to the corrected position command 29a by the galvano control unit 10, and the galvano mirrors 11X and 11Y. to position

In step S7 , the control device 25 controls the laser oscillator 4 according to the laser output command 28 . The command generating unit 2 sends a laser output command 28 to the laser control unit 3 . The laser control unit 3 controls the laser oscillator 4 according to the laser output command 28 . When the laser oscillator 4 outputs the pulsed laser light 5 , the laser processing apparatus 1 forms a processing hole in the to-be-processed object 16 .

In step S8, the control apparatus 25 determines whether or not to complete|finish a process. The command generation unit 2 checks the presence or absence of a hole 17 to be machined next after the machining hole is formed. If there is a hole 17 to be machined next, it is determined that the machining is not finished. When processing is not finished (step S8, No), the control device 25 repeats the procedure from step S2 for the next processing hole. When there is no hole 17 to be machined next, it is determined that the machining is finished. When finishing processing (step S8, Yes), the control apparatus 25 ends the operation|movement by the procedure shown in FIG. As mentioned above, the laser processing apparatus 1 drills the to-be-processed object 16 based on a processing program.

In Embodiment 1, although the sensor state determination part 30 demonstrated the case where the sensor valid period and the sensor invalid period were judged based on the laser output command 28, the detection signal of the pulsed laser beam 5 was demonstrated. Based on this, the sensor valid period and the sensor invalid period may be determined. The laser output shown in Fig. 3B can be simulated by the detection signal. A part of the pulsed laser light 5 is branched by a beam splitter disposed near the exit port of the laser oscillator 4, and the branched light is detected by a high-speed laser power sensor, so that the control device 25 detects the corresponding detection. signal can be obtained.

According to the first embodiment, the laser processing apparatus 1 measures the temperature of the fθ lens 15 by detecting infrared rays radiated from the incident region 22 . The laser processing apparatus 1 calculates|requires the temperature information from which the influence of the pulsed laser beam 5 reflected by the f(theta) lens 15 was removed. The laser processing apparatus 1 correct|amends the position command 29 based on the said temperature information. The laser processing apparatus 1 can instantaneously and accurately measure the temperature of the fθ lens 15 in the incident region 22 without being affected by the reflected light 21 . Since the laser processing apparatus 1 can measure the temperature of the f(theta) lens 15 instantaneously and accurately, high-precision correction of an irradiation position becomes possible. Thereby, the laser processing apparatus 1 achieves the effect that the improvement of a processing precision becomes possible.

In Embodiment 1, the laser processing apparatus 1 provided with the radiation temperature sensor 8 which has a sensitivity in the wavelength range of 8 micrometers - 12 micrometers was demonstrated. In this wavelength range, when the temperature of the fθ lens 15 is around 25°C to 30°C, the intensity of infrared rays emitted from the fθ lens 15 becomes the strongest. Therefore, the radiation temperature sensor 8 having a sensitivity in a wavelength range of 8 µm to 12 µm is suitable as a sensor for detecting infrared rays emitted from the fθ lens 15 . Moreover, the radiation temperature sensor 8 which has a sensitivity in the wavelength range of 8 micrometers - 12 micrometers also has the advantage that it is comparatively cheap and easy to use. Since a wavelength range of 9.3 μm to 10.6 μm, which is a wavelength range of a CO ₂ laser, is included in the wavelength range of 8 μm to 12 μm, the laser processing apparatus 1 includes a pulse laser reflected by the fθ lens 15 in the first embodiment. It was decided that the temperature information from which the influence of the light 5 was removed is calculated|required. In the following embodiment 2, an example in which the influence of the pulsed laser light 5 reflected by the fθ lens 15 is eliminated by using a radiation temperature sensor having sensitivity in a wavelength region other than the wavelength region of 9.3 μm to 10.6 μm. explain about

Embodiment 2.

In the laser processing apparatus according to the second embodiment, the radiation temperature sensor has sensitivity in a wavelength range other than the wavelength range of 9.3 μm to 10.6 μm, and emits infrared rays emitted from the fθ lens 15 in the vicinity of 25° C. to 30° C. detect In Embodiment 2, the same code|symbol is attached|subjected to the same component as said Embodiment 1, and the structure different from Embodiment 1 is mainly demonstrated.

Here, the measurement wavelength of the radiation temperature sensor in Embodiment 2 is demonstrated. It is a figure for demonstrating the measurement wavelength of the radiation temperature sensor in Embodiment 2. FIG. 7, the graph which shows the infrared rays transmission characteristic in air|atmosphere is shown. The radiation temperature sensor measures the temperature of the fθ lens 15 by detecting infrared rays passing through the atmosphere. For this reason, it is required that the measurement wavelength of a radiation temperature sensor be a wavelength with high transmittance|permeability in air|atmosphere.

According to FIG. 7, the transmittance|permeability in air|atmosphere is comparatively high in the wavelength range of 8 micrometers - 13.5 micrometers. In the following description, a wavelength range of 8 µm to 13.5 µm is referred to as a “10 µm wavelength band”. The wavelength of the 10 µm wavelength band is suitable for the measurement wavelength of the radiation temperature sensor. On the other hand, the transmittance is zero in a wavelength range of 14 µm or more and a wavelength range of 5.5 µm to 7.5 µm. A wavelength range of 14 µm or more and a wavelength range of 5.5 µm to 7.5 µm are not suitable for the measurement wavelength of the radiation temperature sensor. The wavelength range of 3.0 µm to 5.0 µm includes wavelengths having a large transmittance but having a relatively high transmittance. In the following description, a wavelength range of 3.0 µm to 5.0 µm is referred to as a “4 µm wavelength band”. In the 4 µm wavelength band, the wavelength range of 3.4 µm to 4.2 µm has high transmittance.

In Embodiment 2, the wavelength range in which the radiation temperature sensor has sensitivity includes a wavelength band of 4 µm. An infrared detector using indium antimony (InSb) is mentioned as an infrared detector which can measure infrared rays in a 4 micrometer wavelength band. When the temperature of the fθ lens 15 was measured by a radiation temperature sensor using InSb, it was confirmed that good measurement was possible without being affected by the reflected light 21 of the CO ₂ laser. The measurement wavelength of the radiation temperature sensor using InSb is 3 μm to 5 μm. The wavelength range of 9.3 µm to 10.6 µm is not included in the measurement wavelength of the radiation temperature sensor using InSb. In Embodiment 2, since the radiation temperature sensor is an infrared detector containing InSb, it has sensitivity in a wavelength range other than the wavelength range of 9.3 μm to 10.6 μm, and an fθ lens 15 near 25° C. to 30° C. ) can detect infrared radiation from

8 : is a figure which shows the structure of 1 A of laser processing apparatuses which concern on Embodiment 2. FIG. A laser processing apparatus 1A according to the second embodiment includes a lens temperature measuring unit 49 that measures the temperature of the fθ lens 15 to obtain temperature information of the fθ lens 15 . The lens temperature measuring unit 49 has a radiation temperature sensor 48 . The radiation temperature sensor 48 is a non-contact temperature sensor and is an infrared detector containing InSb. The radiation temperature sensor 48 has a sensitivity in a wavelength range of 3 μm to 5 μm. The radiation temperature sensor 48 is arrange|positioned above the incident area|region 22 shown in FIG. The radiation temperature sensor 48 measures the temperature of the fθ lens 15 in the incident region 22 by detecting infrared rays emitted from the incident region 22 .

The control device 45 is the same as the control device 25 of the first embodiment except that the temperature calculation unit 7 is not provided. The lens temperature measurement unit 49 outputs temperature information that is a measurement value of the radiation temperature sensor 48 to the galvano command conversion unit 6 . The lens temperature measuring unit 49 outputs the measured value of the radiation temperature sensor 48 at the time t as θ(t) which is the temperature information of the fθ lens 15 at the time t.

Next, an operation of the lens temperature measuring unit 49 will be described with reference to FIG. 9 . 9 is a diagram for explaining a laser output command 28, a laser output, and a temperature measurement result in the second embodiment.

Fig. 9(a) shows a change in a signal that is a laser output command 28 output from the command generation unit 2 to the laser control unit 3 . Fig. 9(a) is the same as Fig. 3(a). Fig. 9(b) shows a change in the laser output by the laser oscillator 4, that is, a change in the output of the pulsed laser light 5. As shown in FIG. Fig. 9(b) is the same as Fig. 3(b).

FIG. 9(c) shows the output of the radiation temperature sensor 48, that is, the measured value of the radiation temperature sensor 48. As shown in FIG. FIG. 9( d ) shows temperature information output from the lens temperature measuring unit 49 , that is, the measurement result of the lens temperature measuring unit 49 . The output of the radiation temperature sensor 48 shown in FIG.9(c) and the output of the lens temperature measuring part 49 shown in FIG.9(d) are the same.

As shown in FIG. 9C , the output of the radiation temperature sensor 48 is not affected by the reflected light 21 , and changes gently so as to correspond to the time constant of the fθ lens 15 . This indicates that the temperature of the fθ lens 15 is accurately measured by the radiation temperature sensor 48 . Accordingly, the lens temperature measuring unit 49 may output accurate temperature information of the fθ lens 15 to the galvano command converting unit 6 .

According to the second embodiment, the laser processing apparatus 1A measures the temperature of the fθ lens 15 using the radiation temperature sensor 48 having a sensitivity in a wavelength range of 3 µm to 5 µm. The laser processing apparatus 1A uses the radiation temperature sensor 48 which has no sensitivity in the wavelength range of the pulsed laser beam 5, and the influence of the pulsed laser beam 5 reflected by the fθ lens 15 is eliminated. Obtain temperature information. The laser processing apparatus 1A can instantaneously and accurately measure the temperature of the fθ lens 15 in the incident region 22 without being affected by the reflected light 21 . The laser processing apparatus 1A correct|amends the position command 29 based on the said temperature information, and high-precision correction of an irradiation position becomes possible. Thereby, 1 A of laser processing apparatuses achieve the effect that the improvement of a processing precision becomes possible.

In addition, although the material of the radiation temperature sensor 48 demonstrated that it is InSb in Embodiment 2, the material of the radiation temperature sensor 48 may be indium gallium arsenide (InGaAs). In the laser processing apparatus 1A, even when the material of the radiation temperature sensor 48 is InGaAs, the effect similar to the case where the material of the radiation temperature sensor 48 is IsSb can be acquired.

In Embodiment 1, the laser processing apparatus 1 which measures the average temperature of the f(theta) lens 15 using the one radiation temperature sensor 8 was demonstrated. In Embodiment 2, the laser processing apparatus 1A which measures the average temperature of the f(theta) lens 15 using one radiation temperature sensor 48 was demonstrated. The average temperature of the fθ lens 15 may be measured by using a plurality of radiation temperature sensors. In the following Embodiment 3, an example in which the average temperature of the fθ lens 15 is measured using a plurality of radiation temperature sensors will be described.

Embodiment 3.

The laser processing apparatus according to the third embodiment measures the average temperature of the fθ lens 15 using a plurality of radiation temperature sensors. In Embodiment 3, the same code|symbol is attached|subjected to the same component as said Embodiment 1 or 2, and the structure different from Embodiment 1 or 2 is mainly demonstrated.

Depending on the pattern of the plurality of holes 17 formed in the workpiece 16 , the pulsed laser light 5 may enter a deflected region among the incident regions 22 shown in FIG. 2 . In this case, a temperature gradient may occur in the incident region 22 . The refractive index of the fθ lens 15 changes not only with changes in average temperature but also with temperature gradients. In the third embodiment, the laser processing apparatus uses a plurality of radiation temperature sensors in order to obtain temperature information including a temperature gradient. The laser processing apparatus makes it possible to correct the irradiation position with higher precision by performing correction according to the change in the average temperature of the fθ lens 15 and the temperature gradient of the incident region 22 .

In Embodiment 3, a plurality of divided regions are set in the incident region 22, and the temperature of each divided region is measured using a plurality of radiation temperature sensors. Further, in the third embodiment, the incident region 22 is divided into four divided regions, and the temperature of each divided region is measured using four radiation temperature sensors. The number of divided regions and the number of radiation temperature sensors may be appropriately changed.

10 : is a figure which shows the structure of the laser processing apparatus 1B which concerns on Embodiment 3. FIG. The laser processing apparatus 1B concerning Embodiment 3 has the lens temperature measuring part 59 which measures the temperature of the f(theta) lens 15. As shown in FIG. The lens temperature measuring unit 59 has four radiation temperature sensors 58A, 58B, 58C and 58D.

Each of the radiation temperature sensors 58A, 58B, 58C, and 58D has a sensitivity in a wavelength band of 4 µm, similarly to the radiation temperature sensor 48 of the second embodiment. Each of the radiation temperature sensors 58A, 58B, 58C, and 58D is a non-contact temperature sensor and is an infrared detector containing InSb. Each of the radiation temperature sensors 58A, 58B, 58C, and 58D has a sensitivity in a wavelength range of 3 µm to 5 µm. The radiation temperature sensors 58A, 58B, 58C, and 58D measure the temperature of the fθ lens 15 by dividing and detecting infrared rays emitted from each of the four divided regions. The lens temperature measuring unit 59 individually measures a temperature for each of the plurality of divided regions included in the incident region 22 , and obtains temperature information for each divided region.

The control device 55 is the same as the control device 45 of the second embodiment, except that the galvano command conversion unit 56 is provided instead of the galvano command conversion unit 6 . The lens temperature measuring unit 59 outputs temperature information that is a measurement value of each of the radiation temperature sensors 58A, 58B, 58C, and 58D to the galvano command converting unit 56 serving as a correction unit.

The galvano command conversion unit 56 corrects the position command 29 based on the temperature information output from the lens temperature measurement unit 59 . The galvano command conversion unit 56 corrects the position command 29 based on the temperature information for each of the plurality of divided regions. The galvano command conversion part 56 outputs the position command 29a which is the position command 29 after correction|amendment by correct|amending the position command 29. As shown in FIG. The galvano command conversion part 56 outputs the position command 29a which is the position command 29 which is not corrected, when the position command 29 is not corrected.

11 is a diagram showing a plurality of divided regions 62A, 62B, 62C, and 62D set in the incident region 22 of the fθ lens 15 in the third embodiment. 12 is a diagram for explaining measurement regions 63A, 63B, 63C, and 63D that are objects of temperature measurement by the lens temperature measurement unit 59 in the third embodiment. 11 and 12, the fθ lens 15 fixed to the lens frame 14 is shown as viewed from the vertical direction.

As shown in Fig. 11, the incident region 22 is divided into 4 divided regions 62A, 62B, 62C, and 62D of 2x2. The areas of each of the divided regions 62A, 62B, 62C, and 62D are all equal.

Fig. 12 shows divided regions 62A, 62B, 62C, and 62D shown in Fig. 11 and measurement regions 63A, 63B, 63C, and 63D. The measurement area 63A is an area within the divided area 62A. The measurement area 63B is an area within the divided area 62B. The measurement area 63C is an area within the divided area 62C. The measurement area 63D is an area within the divided area 62D.

The radiation temperature sensor 58A measures the average temperature of the fθ lens 15 in the measurement area 63A by measuring the temperature in the measurement area 63A. The radiation temperature sensor 58B measures the average temperature of the fθ lens 15 in the measurement area 63B by measuring the temperature in the measurement area 63B. The radiation temperature sensor 58C measures the average temperature of the fθ lens 15 in the measurement area 63C by measuring the temperature in the measurement area 63C. The radiation temperature sensor 58D measures the average temperature of the fθ lens 15 in the measurement area 63D by measuring the temperature in the measurement area 63D.

The lens temperature measuring unit 59 includes temperature information that is a measurement value of the radiation temperature sensor 58A, temperature information that is a measurement value of the radiation temperature sensor 58B, temperature information that is a measurement value of the radiation temperature sensor 58C, and measurement of the radiation temperature sensor 58D. The temperature information, which is a value, is output to the galvano command conversion unit 56 .

Next, the process by the galvano command conversion part 56 is demonstrated. The position command 29 from the command generation unit 2 and the temperature information from the lens temperature measurement unit 59 are input to the galvano command conversion unit 56 . The galvano command conversion unit 56 obtains a temperature conversion parameter based on the temperature information. The galvano command conversion unit 56 corrects the position command 29 based on the calculated temperature conversion parameter. The galvano command conversion part 56 outputs the position command 29a which is the position command 29 after correction|amendment based on temperature to the galvano control part 10.

Xg(k) which is the position command 29 with respect to the galvano-scanner 13X, and Yg(k) which is the position command 29 with respect to the galvano-scanner 13Y are input to the galvano command conversion part 56. do. The galvano command conversion unit 56 receives temperature information of the fθ lens 15 , θ _A (t), θ _B (t), θ _C (t), and θ _D (t). Let θ _A (t) be temperature information that is a measurement value of the radiation temperature sensor 58A at time t. Let θ _B (t) be temperature information that is a measured value of the radiation temperature sensor 58B at time t. Let θ _C (t) be temperature information that is a measured value of the radiation temperature sensor 58C at time t. Let θ _D (t) be temperature information that is a measured value of the radiation temperature sensor 58D at time t.

The galvano command conversion unit 56 calculates ΔXg(k) and ΔYg(k), which are correction amounts based on temperature information, by the procedure shown below. In addition, the calculation method shown in Embodiment 3 is one example, and you may change a calculation method suitably.

The galvano command conversion unit 56 calculates Δθ _A (t), which is the amount of temperature change from θ0, for the divided region 62A. Δθ _A (t) is represented by the following formula (5). The galvano command conversion unit 56 calculates Δθ _B (t), which is the amount of temperature change from θ0, for the divided region 62B. Δθ _B (t) is represented by the following formula (6). The galvano command conversion unit 56 calculates Δθ _C (t), which is the amount of temperature change from θ0, for the divided region 62C. Δθ _C (t) is represented by the following formula (7). The galvano command conversion unit 56 calculates Δθ _D (t), which is the amount of temperature change from θ0, for the divided region 62D. Δθ _D (t) is expressed by the following formula (8).

[Equation 5]

…(5)

… (5)

…(6)

… (6)

…(7)

… (7)

…(8)

… (8)

The galvano command conversion part 56 calculates|requires Pg _A which is a temperature conversion parameter with respect to division|segmentation area|region 62A using following Formula (9). The galvano command conversion part 56 calculates|requires _PgB which is a temperature conversion parameter with respect to division|segmentation area|region 62B using following Formula (10). The galvano command conversion part 56 calculates|requires Pg _C which is a temperature conversion parameter with respect to division|segmentation area|region 62C using following Formula (11). The galvano command conversion part 56 calculates|requires PgD which is a temperature conversion parameter with respect to division|segmentation area|region _62D using following Formula (12).

[Equation 6]

…(9)

… (9)

…(10)

… (10)

…(11)

… (11)

…(12)

… (12)

a0 _A , a1 _A , a2 _A , b0 _A , b1 _A , b2 _A , a0 _B , a1 _B , a2 _B , b0 _B , b1 _B , b2 _B , a0 _C , a1 _C , a2 _C , b0 _C , b1 _C , b2 _C , a0 _D , a1 _D , a2 _D , b0 _D , b1 _D , and b2 _D are each a correction coefficient. A correction coefficient is calculated|required beforehand by drilling-processing to test boards, such as an acrylic board, using the laser processing apparatus 1B. Based on the amount of deviation between the position of the hole 17 formed in the test board and the command position, and the temperature information of the fθ lens 15 obtained by the lens temperature measuring unit 59 during processing, adjustment is made so that the processing error is minimized. Each correction coefficient obtained is obtained.

The galvano command conversion part 56 calculates|requires (DELTA)Xg(k) and (DELTA)Yg(k) shown by following Formula (13) by using said Formula (9) - (12).

[Equation 7]

…(13)

… (13)

The galvano command conversion unit 56 uses the formula (13) and Xg(k) and Yg(k) which are the position commands 29, and Xgout(k) which is the position command 29 after correction based on the temperature. ), Ygout(k) is obtained. Xgout(k) and Ygout(k) are represented by the following formula (14). The galvano command conversion unit 56 outputs Xgout(k) and Ygout(k) as the position command 29a.

[Equation 8]

…(14)

… (14)

In addition, the average temperature of the fθ lens 15 is an average value of θ _A (t), θ _B (t), θ _C (t), and θ _D (t). The amount of change in the average temperature of the fθ lens 15 is an average value of Δθ _A (t), Δθ _B (t), Δθ _C (t), and Δθ _D (t). The temperature gradient of the fθ lens 15 is obtained by the difference in the amount of change in the average temperature between the divided regions 62A, 62B, 62C, and 62D. The temperature gradient is, for example, θ _A (t) - θ _B (t), θ _A (t) - θ _C (t), θ _A (t) - θ _D (t), θ _B (t) - It is represented by θ _C (t), θ _B (t) - θ _D (t), and θ _C (t) - θ _D (t).

The galvano command conversion unit 56 corrects the position command 29 by obtaining Xgout(k) and Ygout(k). The laser processing apparatus 1B can form the hole 17 in an accurate position by correct|amending the position command 29 in the galvano command conversion part 56. As shown in FIG. The galvano command conversion unit 56, based on the temperature information of each of the divided regions 62A, 62B, 62C, 62D, according to the change in the average temperature of the fθ lens 15 and the temperature gradient of the incident region 22 correction can be made. Thereby, the laser processing apparatus 1B becomes possible to correct|amend an irradiation position with higher precision.

In Embodiment 3, the incident region 22 can be divided into any number of divided regions. In the laser processing apparatus 1B, the number of radiation temperature sensors equal to the number of divided areas in the incident area 22 is provided. Thereby, in the laser processing apparatus 1B, the correction|amendment of the irradiation position according to the change of the average temperature of the f(theta) lens 15 and the temperature gradient of the incident area|region 22 becomes possible.

The lens temperature measuring unit 59 according to the third embodiment is the same as the lens temperature measuring unit 49 in the second embodiment except that a plurality of radiation temperature sensors are provided. As an application of the third embodiment, the lens temperature measuring unit 59 may be one in which a plurality of radiation temperature sensors are provided in the same lens temperature measuring unit 9 as in the first embodiment. In this case, the lens temperature measuring unit 59 has a plurality of radiation temperature sensors and a temperature calculating unit 7 . Each of the plurality of radiation temperature sensors has a sensitivity in the 10 µm wavelength band, similarly to the radiation temperature sensor of the first embodiment.

According to Embodiment 3, the laser processing apparatus 1B measures a temperature individually with respect to each of the several division area included in the incidence area|region 22, and calculates|requires temperature information for every division area. The laser processing apparatus 1B correct|amends the position instruction|command 29 based on the temperature information about each of a some division|segmentation area|region. The laser processing apparatus 1B can perform correction including the change in the average temperature of the fθ lens 15 and the temperature gradient of the incident region 22 . Thereby, the laser processing apparatus 1B achieves the effect that the improvement of a processing precision becomes possible.

Next, the hardware configuration of the control devices 25 , 45 , 55 according to the first to third embodiments will be described. 13 : is a figure which shows the example of the hardware structure of the control apparatuses 25, 45, 55 which the laser processing apparatuses 1, 1A, 1B which concern on Embodiment 1-3 have. Fig. 13 shows a hardware configuration in a case where the functions of the control devices 25, 45, 55 are realized by using hardware for executing a program.

The processor 71 is a CPU (Central Processing Unit). The processor 71 may be a processing device, an arithmetic device, a microprocessor, a microcomputer, or a DSP (Digital Signal Processor). The memory 72 is RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), or EEPROM (Electrically Erasable Programmable Read Only Memory).

The storage device 73 is a hard disk drive (HDD) or a solid state drive (SSD). A program for causing the computer to function as the control devices 25 , 45 , 55 is stored in the storage device 73 . The processor 71 reads the program stored in the storage device 73 into the memory 72 and executes it.

The program may be stored in a storage medium capable of being read by a computer system. The control devices 25 , 45 , 55 may store the program recorded on the storage medium in the memory 72 . The storage medium may be a portable storage medium that is a flexible disk or a flash memory that is a semiconductor memory. The program may be installed in the computer system via a communication network from another computer or server device.

Each function of the command generation unit 2, the laser control unit 3, the galvano command conversion units 6 and 56, the temperature calculation unit 7, the galvano control unit 10, and the XY table control unit 20 is a processor (71) and software. Each of these functions may be realized by a combination of the processor 71 and firmware, or may be realized by a combination of the processor 71, software, and firmware. Software or firmware is described as a program and stored in the storage device 73 .

The interface circuit 74 receives signals from radiation temperature sensors 8, 48, 58A, 58B, 58C, 58D, which are devices connected to hardware. The interface circuit 74 transmits a signal to the laser oscillator 4, the galvano scanners 13X and 13Y, and the XY table 18, which are devices connected to hardware.

The configuration shown in each of the above embodiments represents an example of the content of the present disclosure. The configuration of each embodiment can be combined with other known techniques. The structures of each embodiment may be combined suitably. It is possible to omit or change a part of the structure of each embodiment in the range which does not deviate from the summary of this indication.

1, 1A, 1B: laser processing device 2: command generation unit
3: laser control unit 4: laser oscillator
5: pulse laser beam 6, 56: galvano command conversion part
7: Temperature calculator
8, 48, 58A, 58B, 58C, 58D: Radiant temperature sensor
9, 49, 59: lens temperature measurement unit 10: galvano control unit
11X, 11Y: Galvanometer Mirror 12X, 12Y: Motor
13X, 13Y: Galvano Scanner 14: Lens Frame
15: fθ lens 16: work piece
17, 17a, 17b, 17c: hole 18: XY table
19: top table 20: XY table control unit
21: reflected light 22: incident area
23, 63A, 63B, 63C, 63D: Measuring area 25, 45, 55: Control unit
26: machining head 27, 29, 29a: position command
28: laser output command 30: sensor state determination unit
31: sensor output storage unit 32: temperature estimation unit
33: temperature information conversion unit 34: temperature calculation parameter
35: sensor status flag 40, 41: position
62A, 62B, 62C, 62D: Partition 71: Processor
72: memory 73: memory device
74: interface circuit

Claims (7)

a laser oscillator for outputting pulsed laser light;
a galvanometer scanner having a galvanometer mirror, deflecting the pulse laser beam by reflection of the pulse laser beam in the galvanometer mirror, and rotating the galvanometer mirror by control according to a position command;
a lens having an incident area on which the pulsed laser light deflected in the galvano scanner is incident, and condensing the pulsed laser light incident on the incident area;
a lens temperature measuring unit that measures the temperature of the lens by detecting infrared rays emitted from the incident region and obtains temperature information of the lens;
and a correction unit for correcting the position command based on the temperature information. The method according to claim 1,
and a command generator for generating a laser output command for controlling the laser oscillator and outputting the laser output command;
The lens temperature measuring unit determines a period from when a preset period elapses after the laser output command is switched from on to off until the output of the laser output command turns on as a sensor valid period, The said temperature information in the said sensor validity period is calculated|required, The laser processing apparatus characterized by the above-mentioned. 3. The method according to claim 2,
The said lens temperature measuring part estimates the said temperature information in the sensor invalidation period which is a period other than the said sensor valid period based on the temperature measured in the said sensor valid period, The laser processing apparatus characterized by the above-mentioned. 4. The method according to claim 2 or 3,
The laser oscillator is a carbon dioxide laser,
The lens temperature measuring unit laser processing apparatus, characterized in that it has a radiation temperature sensor having a sensitivity in a wavelength range of 9.3㎛ to 10.6㎛. The method according to claim 1,
The laser oscillator is a carbon dioxide laser,
The lens temperature measuring unit laser processing apparatus, characterized in that it has a radiation temperature sensor having a sensitivity in a wavelength range of 3㎛ to 5㎛. 6. The method of claim 5,
The radiation temperature sensor is a laser processing apparatus, characterized in that the infrared detector containing indium antimony. 7. The method according to any one of claims 1 to 6,
The lens temperature measuring unit separately measures a temperature for each of a plurality of divided regions included in the incident region to obtain the temperature information for each of the divided regions,
The correction unit corrects the position command based on the temperature information for each of the plurality of divided regions.

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