JP4698092B2 - Galvano scanner device and control method thereof - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a galvano scanner device for moving an irradiation position of a laser beam and a control method thereof, and more particularly to use in a laser drill machine that irradiates a laser beam and punches a hole in a suitable place such as a printed wiring board. The present invention relates to a suitable galvano scanner device and a control method thereof.
[0002]
[Prior art]
In a laser drill machine, a laser beam from a laser light source is deflected by, for example, a galvano scanner and is incident on a desired position on a workpiece as a workpiece. For example, when drilling a printed wiring board or the like using such a laser drill machine, a high throughput is required, and a high speed operation of the galvano scanner is required.
[0003]
In general, galvano scanners have different driving characteristics depending on the operating angle. This difference in characteristics is slight, but cannot be ignored in accordance with the demand for higher speed and higher accuracy.
[0004]
FIG. 9 is a graph showing an error between a target machining position and an actual machining point when drilling is performed in one direction under a certain machining condition. The horizontal axis represents the distance from the start point of the target machining position, and the vertical axis represents the error of the machining point from the target machining position. As the machining position advances, a positive error occurs and the accuracy deteriorates. This is a phenomenon that occurs because the laser is irradiated even though the settling is delayed due to a change in the drive characteristics of the machining position.
[0005]
Conventionally, as countermeasures against such deterioration of machining accuracy, measures have been taken to slow down the drive speed or narrow the machining area so as not to cause a difference in characteristics, but in each case the throughput is lowered. It was.
[0006]
For the purpose of high-speed operation of the galvano scanner, Japanese Patent Application Laid-Open No. 2000-117476 proposes setting a “set waiting time” according to the moving angle of the scanner mirror. Specifically, it is regarded that the positioning of the scanner mirror is completed after the “set waiting time” has elapsed from the output timing of the command value for driving the scanner mirror. Then, as the movement angle (movement distance) of the scanner mirror is smaller, the “set waiting time” is reduced, thereby shortening the machining tact of the workpiece.
[0007]
[Problems to be solved by the invention]
However, in the technique of the above publication, the “set waiting time” is determined as the required time from the output of the command value. Therefore, particularly when the moving angle of the scanner mirror is large, the “setting waiting time” and the actual positioning are determined. The error with time increases. Such an error becomes an error factor of the drilling process. To avoid this error, if the “set waiting time” is lengthened and a large allowable error is taken, the throughput of the drilling process decreases due to the accumulation.
[0008]
Therefore, the present invention has an object to provide a galvano scanner device that enables processing such as drilling with a small processing error and high throughput regardless of factors such as the angle of the scanner mirror, and a control method thereof. And
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a galvano scanner device that moves an irradiation position of a laser beam by a mirror and a mirror driving device, wherein the mirror driving device sets a predetermined set point including a target angle. A settling range detecting means for detecting that the range has been reached, and a standby time expected to be required to reach and hold the target angle after the mirror drive position has reached the settling range, Control means for changing the angle according to the angle of the mirror.
[0010]
In the above apparatus, since the control means changes the waiting time that is expected to be taken until the mirror driving position reaches the target angle and is held after reaching the settling range, according to the angle of the mirror. By using a standby time with a small error, it is possible to perform processing such as a high-throughput laser via with a small error. That is, the waiting time corresponds to the remaining time for positioning from the stage when the mirror drive position approaches the target angle and reaches the settling range, so the set waiting time is determined as the required time from the command value output. Compared to the case, a short-term prediction is sufficient, and the positioning timing can be predicted relatively accurately. Therefore, it is possible not only to accurately predict the time when the driving position of the mirror becomes the target angle and accurately position the laser beam at the irradiation position, but also to accurately determine the positioning timing, based on the waiting time. Since the next operation and its preparation can be performed, the throughput of processing using a laser beam can be increased. Here, the settling range may correspond to a preliminary period for starting preparation for the operation of another predetermined component that operates in relation to the operation of the mirror. Apart from the preliminary period, it may be a specially provided range for ensuring accuracy.
[0011]
In a specific aspect of the above apparatus, the waiting time is set to the value of the mirror. Up to the target angle It changes according to a drive angle, a target angle, or both.
[0012]
In another specific aspect of the apparatus, the waiting time is Laser beam irradiation A standby time table stored corresponding to the position is provided.
[0013]
In another specific aspect of the apparatus, the waiting time is set for each mirror scanning direction.
[0014]
In another specific aspect of the above apparatus, the apparatus further includes waveform forming means for forming a command waveform for driving the mirror as digital data. In this case, since a desired command waveform can be given to the mirror driving device with a high degree of freedom, the mirror can be efficiently held at the target angle in a short time, and the standby time can be predicted accurately.
[0015]
In another specific aspect of the apparatus, the waiting time includes a predetermined component that operates in relation to the operation of the mirror and a delay in operation of a control device that controls at least the operation of the predetermined component. Set by. In this case, the linkage with other predetermined parts can be controlled efficiently, and the throughput can be further increased. Here, the other components mean, for example, a laser oscillation device, a stage driving device that supports a workpiece, and the like.
[0016]
In another specific aspect of the apparatus, a characteristic difference detection unit that obtains a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving device with a reference characteristic, and the characteristic difference detection unit Based on the characteristic difference obtained by the above, for example, a correction means for correcting the standby time extracted from the standby time table is further provided. In this case, since the standby time can be corrected in consideration of the characteristic difference corresponding to the situation (response deterioration) until the mirror reaches the settling range, the throughput of processing using the laser beam can be further increased.
[0017]
In another specific aspect of the above apparatus, the apparatus further comprises characteristic difference detection means for obtaining a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving apparatus with a reference characteristic, and the standby time. Are stored as a plurality of standby time tables according to the plurality of patterns of the characteristic difference. In this case, the standby time can be determined in consideration of the characteristic difference corresponding to the situation until the mirror reaches the settling range, so that the throughput of processing using the laser beam can be further increased.
[0018]
Further, in another specific aspect of the above apparatus, the apparatus further comprises characteristic difference detection means for obtaining a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving apparatus with a reference characteristic. The means corrects a command waveform for driving the mirror according to the characteristic difference obtained by the characteristic difference detecting means. In this case, the command waveform can be corrected in consideration of the characteristic difference corresponding to the situation until the mirror reaches the settling range, so that the throughput of processing using the laser beam can be further increased.
[0019]
In another specific aspect of the above apparatus, the apparatus further includes a temperature sensor that detects temperatures in the vicinity of the mirror and the mirror driving device, and stores the standby time for each temperature, for example, as a standby time table. In this case, since the standby time can be determined in consideration of the temperature change, the accuracy of processing using the laser beam can be increased and the throughput can be further increased.
[0020]
According to another specific aspect of the above apparatus, when the mirror enters a predetermined convergence range that is narrower than the settling range and includes the vicinity of the target angle for a predetermined time, the positioning of the mirror is completed. Further, positioning determining means for determining that it has been performed is further provided. In this case, it is possible to increase the throughput of processing using a laser beam while ensuring the processing accuracy by setting the convergence range.
[0021]
The present invention is also a method of controlling a galvano scanner device in which a laser beam irradiation position is moved by a mirror and a mirror driving device, wherein the target position is reached after the driving position of the mirror reaches a predetermined settling range including a target angle. A step of determining a standby time expected to be required to reach and hold the angle according to the angle of the mirror, for example, using a standby time table; and the mirror driving device determines the driving position of the mirror. Detecting the arrival within the settling range, and, for example, outputting the positioning completion signal after waiting until the operation of the mirror is completed based on the waiting time table, for example, when reaching the settling range; Is provided.
[0022]
In the above method, the standby time expected to be required to reach and hold the target angle after the driving position of the mirror reaches the settling range is stored as, for example, a standby time table in accordance with the mirror angle. Therefore, it is possible to process a high-throughput laser via or the like with a small error by using a standby time with a small error.
[0023]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a diagram illustrating the structure of a laser drill machine incorporating a galvano scanner device according to an embodiment of the present invention.
[0024]
The illustrated laser drill machine includes a laser oscillator 10 that emits, for example, a pulsed laser beam LB as a light source, a galvano scanner 20 that deflects the laser beam LB from the laser oscillator 10 in a desired direction, and a laser that passes through the galvano scanner 20. An fθ lens 30 that focuses the light beam LB on the surface of the workpiece W, a stage 50 that supports the workpiece W that is a printed wiring board, a scanner control unit 60 that controls the operation of the galvano scanner 20, and a stage 50 Are provided with a stage control unit 70 for controlling the operation of the laser drilling machine and a host controller 80 for controlling the overall operation of the laser drill machine. Here, the galvano scanner 20 and the scanner control unit 60 constitute a galvano scanner device.
[0025]
The laser oscillator 10 is, for example, an excimer laser that emits an ultraviolet laser beam LB in a pulse shape, or a CO 2 that emits an infrared laser beam LB in a pulse shape. ₂ It can be a laser or the like. Note that the emission timing of the laser beam LB from the laser oscillator 10 is controlled by the host controller 80.
[0026]
The galvano scanner 20 includes a pair of scanner mirrors M1 and M2 for deflecting the laser beam LB, mirror drive devices 21 and 22 for rotating the scanner mirrors M1 and M2 in two orthogonal directions, and both mirrors. Temperature sensors 24 and 25 are provided in the vicinity of the drive devices 21 and 22 to detect their temperatures.
[0027]
The fθ lens 30 moves the laser beam LB on the workpiece W at a constant speed when the scanner mirrors M1 and M2 rotate at a constant angular speed. Thereby, the incident spot IS of the pulsed light formed on the surface of the workpiece W by the fθ lens 30 can be moved to an arbitrary point in the XY plane. In the incident spot IS of the pulsed light collected by the fθ lens 30 as described above, the resin layer and the copper thin film on the surface of the workpiece W are decomposed and removed by the ablation phenomenon.
[0028]
The stage 50 can move to an arbitrary position in the XY plane while supporting the workpiece W. That is, when the workpiece W is relatively large, the scanning area (processing area) may be larger than the scanning area in which the via hole can be formed by scanning with the galvano scanner 20. In this case, via holes are formed in units of scanning regions while the workpiece W is moved stepwise as appropriate, and this is repeated to form via holes in the entire workpiece W.
[0029]
Based on an instruction from the host controller 80, the scanner control unit 60 outputs an appropriate signal to the mirror driving devices 21 and 22 of the galvano scanner 20 to hold the scanner mirrors M1 and M2 at arbitrary driving positions, that is, target angles. The necessary signal processing is performed based on the output of the drive angle detection device provided in the mirror drive devices 21 and 22.
[0030]
The stage controller 70 can output an appropriate signal to the stage 50 based on an instruction from the host controller 80 to move the workpiece W on the stage 50 to an arbitrary position. Necessary signal processing is performed based on the output of the position detection device.
[0031]
The host controller 80 includes a computer system or the like, and controls the incident position of the laser beam LB on the workpiece W by operating the galvano scanner 20 via the scanner controller 60. Further, the host controller 80 operates the stage 50 to control the position of the workpiece W with respect to the galvano scanner 20 or the like. The host controller 80 controls the emission timing of the pulsed light from the laser oscillator 10 and the like.
[0032]
FIG. 2 is a block diagram mainly illustrating the circuit configuration of the scanner control unit 60 of FIG. The scanner control unit 60 includes a digital calculator 60a that forms a pair of command signals SID for operating the motors MO1 and MO2 as digital data in accordance with an instruction signal SAA from the host controller 80, and a pair of commands from the digital calculator 60a. A D / A converter 60b that forms a pair of command voltage signals SVW obtained by analogizing the signals SID, and a pair of command current signals SCW based on the pair of command voltage signals SVW from the D / A converter 60b. And a power amplifier 60e and 60f for outputting a pair of output signals SO1 and SO2 obtained by amplifying a pair of command current waveforms SDW from the analog circuit 60d to the pair of motors MO1 and MO2, respectively. . In FIG. 2, the motor MO1 and the angle sensor S1 correspond to the mirror driving device 21 of FIG. 1, and the motor MO2 and the angle sensor S2 correspond to the mirror driving device 23 of FIG.
[0033]
The digital calculator 60a functions as waveform forming means, and forms a pair of command signals SID for operating the mirror driving devices 21 and 22 as digital data in accordance with the instruction signal SAA from the host controller 80, and forms a D / A converter 60b. Output to. The digital calculator 60a monitors the angle states (orientations) of the scanner mirrors M1 and M2 based on the angle signals SA and SB from the A / D converter 60h. The digital calculator 60a monitors the temperature states of the scanner mirrors M1 and M2 and the mirror driving devices 21 and 22 in FIG. 1 based on the temperature signal SC from the A / D converter 60h. Further, the digital calculator 60a monitors whether or not the scanner mirrors M1 and M2 are within the settling range based on the settling range signal SD from the analog circuit 60d. Thus, the digital calculator 60a can detect the timing when the scanner mirrors M1 and M2 enter the settling range, which means that the positioning is near, and the target angle after the scanner mirrors M1 and M2 reach the settling range. It is possible to predict a precise waiting time until convergence. Then, the digital calculator 60a outputs a positioning completion signal SRD indicating positioning completion to the host controller 80 as output means.
[0034]
The analog circuit 60d includes a feedback control circuit, and forms a command current signal SCW based on the command voltage signal SVW from the D / A converter 60b and the angle measurement signal SMA from the angle sensors S1 and S2. The command current signal SCW is output to the power amplifiers 60e and 60f. Here, the command voltage signal SVW is a voltage waveform for converging the scanner mirrors M1 and M2 to the target angle, and the command current signal SCW is a mirror angle corresponding to the command voltage signal SVW. It is the electric current waveform for rotating according to the difference with the mirror angle corresponding to the angle measurement signal SMA. Further, the analog circuit 60d functions as a settling range detection means, generates a setpoint range in- terition SD corresponding to whether or not the scanner mirrors M1 and M2 are in the settling range based on the angle measurement signal SMA, and outputs the digital signal. It outputs to the calculator 60a. Further, the analog circuit 60d generates a deviation SAD or a current angle SAP of the scanner mirrors M1 and M2 based on the angle measurement signal SMA, and outputs it to the digital calculator 60a. Here, the deviation SAD corresponds to the difference between the angle corresponding to the angle measurement signal SMA and the angle corresponding to the command voltage signal SVW.
[0035]
FIG. 3 is a block diagram illustrating a circuit configuration of the digital calculator 60a of FIG. The digital calculator 60a includes a command value generation unit 60cg that forms a pair of command signals SID for operating the mirror driving devices 21 and 22 as digital data based on the instruction signal SAA, an angle signal SAD, SAP, and a settling range. A determination unit 60ad that performs processing such as determination of positioning completion and determination of standby time based on the internal signal SD, temperature signal STE, and the like, and a memory 60me that stores information necessary for processing such as determination of standby time.
[0036]
The command value generating unit 60cg is a pair of command signals for operating the mirror driving devices 21 and 22 based on the pattern for operating the mirror driving devices 21 and 22, that is, the instruction signal SAA including the driving amounts of the scanner mirrors M1 and M2. Form a SID. Both command signals SID correspond to the drive amounts and drive speeds of the motors constituting the mirror drive devices 21 and 22, and change with time to converge to the target value.
[0037]
The determination unit 60ad receives the settling range signal SD, determines the standby time until the positioning is completed based on the standby time table, and outputs the positioning completion signal SRD after this time. The determination unit 60ad can correct the command signal SID for operating the mirror driving devices 21 and 22 based on the monitored signals SAD, SAP, SD, STE and the like. Specifically, for example, when changes in the angle signals SAD and SAP are slower than planned, the characteristics of the pair of command signals SID are changed to cause an angle change with a steeper slope than planned. it can.
[0038]
The memory 60me stores a standby time table Tw that stores the standby time until the scanner mirrors M1 and M2 reach the target angle after the scanner mirrors M1 and M2 reach the set range in association with the drive angle. The memory 60me can also store a reference characteristic Cr in addition to the standby time table Tw. The reference characteristic Cr is an operation waveform in which the standard driving angle of the scanner mirrors M1 and M2 or the standard driving amount of the mirror driving devices 21 and 22 is a function of time.
[0039]
In a laser processing apparatus using a galvano scanner, the operation characteristics of the galvano scanner are non-interfering on the X axis and the Y axis, and therefore the above time setting can be performed separately for the X axis and the Y axis.
[0040]
Hereinafter, the operation of the laser drill machine shown in FIGS. 1 to 3 will be described.
[0041]
First, the workpiece W, which is a printed wiring board, is placed on the stage 50 and fixed.
[0042]
Next, based on an instruction from the host controller 80, while operating the laser oscillator 10, the laser beam LB from the galvano scanner 20 is incident on an appropriate position of the workpiece W on the stage 50 to form a machining hole here. To do. More specifically, the stage 50 is moved in accordance with the output from the stage control unit 70 so that a specific section on the workpiece W becomes an irradiation region of the scanning optical system including the galvano scanner 20 and the fθ lens 30. Move.
[0043]
Next, the galvano scanner 20 is operated in accordance with the output from the scanner control unit 60, and the laser beam LB from the laser oscillator 10 is incident on a proper position of the workpiece W, thereby entering a specific section on the workpiece W. Process holes are formed in a desired arrangement.
[0044]
Next, the stage 50 is moved and moved so that a section adjacent to the specific section becomes an irradiation area of the scanning optical system.
[0045]
Next, processing holes are formed in a desired arrangement in the adjacent section on the workpiece W by a scanning optical system.
[0046]
By repeating the operation as described above, a processing hole is formed at an appropriate position on the entire surface of the workpiece W.
[0047]
In the operation as described above, the scanner control unit 60 operates the galvano scanner 20 in five modes described below.
[0048]
(1) In the first mode, the standby time until the driving of both scanner mirrors M1, M2 is completed is switched based on the standby time table Tw stored in the memory 60me of the digital calculator 60a provided in the scanner control unit 60. The waiting time table Tw used here is the target angle of the scanner mirrors M1 and M2 corresponding to the distance (hole distance) between the machining points, indicating the waiting time until the driving is completed that is held at the target angle after reaching the settling range. It is determined according to the driving amount (angle) until. In response to the instruction signal SAA from the host controller 80 instructing driving of the scanner mirrors M1 and M2, the scanner control unit 60 reads the positioning completion signal after the standby time read from the standby time table Tw according to the drive angle. SRD is output to the host controller 80. The host controller 80 sends a trigger signal to the laser oscillation device 10 as soon as the positioning completion signal is detected.
[0049]
Here, the waiting time table Tw is created by accumulating data by repeating experiments in advance. Specifically, for each of the scanner mirrors M1 and M2, the characteristics of the angle deviation (or current angle) when the magnitude of the drive angle is changed are measured by experiment. From this, it is clarified how the operating characteristics of both scanner mirrors M1 and M2 change under each angle condition, and for each angle condition, a waiting time from reaching the settling range to completion of positioning is determined. The standby time table Tw obtained in this way is incorporated in the memory 60me of the digital calculator 60a.
[0050]
When the digital calculator 60a operates after waiting time elapses, internal processing of the host controller 80 and other electrical components (for example, the laser oscillator 10) between the completion of positioning and the actual irradiation of the laser beam LB. , Stage 50, stage control unit 70, etc.) often results in useless delay time. If such a delay time is experimentally clarified in advance and the standby time is determined by subtracting this delay time when determining the standby time, it is effective for further shortening the processing time. Actually, the standby time stored as the standby time table Tw is corrected by increasing the delay time caused by the operation of the host controller 80 or the like.
[0051]
(2) In the second mode, not only the waiting time until the driving of the scanner mirrors M1 and M2 is completed is switched based on the waiting time table Tw, but the switched waiting time is further changed according to the situation. Specifically, the digital calculator 60a functioning as the characteristic difference detecting means and the correcting means compares the reference characteristic Cr stored in the memory 60me with the deviation or current value of the driving position of the scanner mirrors M1 and M2 every predetermined time. Thus, the characteristic difference is detected, and the standby time extracted from the standby time table Tw is corrected based on the characteristic difference. As a correction method, it is conceivable to apply a coefficient corresponding to the characteristic difference to the standby time extracted from the standby time table Tw according to each operation condition, or to add an offset corresponding to the characteristic difference. Further, a method is conceivable in which several standby time tables Tw are prepared in advance and the standby time tables are switched in accordance with changes in operating characteristics. When comparing the characteristic difference, for example, the overshoot difference in which the overshoot of the driving amounts of the scanner mirrors M1 and M2 is compared with the overshoot of the reference characteristic Cr, and the tracking speed of the scanner mirrors M1 and M2 are set as the tracking speed of the reference characteristic Cr. The compared speed difference can be used.
[0052]
Here, the reference characteristic Cr is a standard operation characteristic in the initial stage of the galvano scanner 20, and the current value (drive angle) when the magnitude of the drive angle is changed for each of the scanner mirrors M1 and M2. Further, the change characteristic of the deviation (angle deviation) is measured by experiment, and the operation characteristic is obtained for each predetermined drive angle range. The reference characteristic Cr changes depending on whether the driving positions of the scanner mirrors M1 and M2 are grasped as deviations or as current values. That is, the deviation reference characteristic Cr corresponds to the difference between the current value and the command value.
[0053]
In addition, the convergence value of the reference characteristic Cr is 0 when controlled using the deviation, but when controlled using the current value, it is necessary to shift so as to match the command value from the host controller 80. There is a characteristic that accurately converges to the command value.
[0054]
(3) In the third mode, not only the waiting time until the driving of the scanner mirrors M1 and M2 is completed is switched based on the waiting time table Tw, but also the driving patterns of the scanner mirrors M1 and M2 are changed. More specifically, the reference characteristic Cr stored in the memory 60me by the digital calculator 60a is compared with the deviation or current value of the driving position of the scanner mirrors M1 and M2 at certain time intervals to detect a characteristic difference. Based on this, the drive patterns of the scanner mirrors M1 and M2 are appropriately corrected. As a correction method, for example, when the overshoot such as the current value is larger than the reference characteristic, the overshoot or inclination of the command value is reduced based on the obtained characteristic difference. Further, when the follow-up speed of the current value or the like is slow, a method of increasing the inclination of the command value based on the obtained characteristic difference can be considered.
[0055]
It should be noted that if the angles of the scanner mirrors M1 and M2 are deviated from the target angles when the driving of the scanner mirrors M1 and M2 is completed, a method of shifting the final value of the command value can be considered. In this case, the convergence value of the reference characteristic Cr is set to a value that deviates from the command value.
[0056]
(4) In the fourth mode, the standby time until the driving of the scanner mirrors M1 and M2 is completed is switched based on the standby time table Tw. The standby time table Tw used at this time takes the temperature of the galvano scanner 20 into consideration. It has become. That is, the scanner control unit 60 waits corresponding to the drive amount and the temperature detection signal STE from the temperature sensors 24 and 25 according to the instruction signal SAA from the host controller 80 that instructs to drive both scanner mirrors M1 and M2. An appropriate waiting time is read from the time table Tw. The scanner control unit 60 outputs the read standby time as a data signal SRD to the host controller 80.
[0057]
Here, the waiting time table Tw is created by accumulating data by repeating experiments while changing the temperature of the galvano scanner 20 in advance. Specifically, for both scanner mirrors M1 and M2, the characteristics of the angle deviation when the drive angle is changed are measured in various temperature ranges, and the waiting time from reaching the settling range to completing the positioning is determined. Determine for each temperature range. The standby time table Tw obtained in this way is incorporated in the memory 60me of the digital calculator 60a.
[0058]
(5) In the fifth mode, the waiting time until the driving of the scanner mirrors M1 and M2 is completed is switched based on the waiting time table Tw. In this case, the positioning is performed when a predetermined period has elapsed after entering a predetermined convergence range. A completion signal is transmitted from the digital calculator 60a to the host controller 80. That is, when the positioning completion determination is made based on the deviation of the drive amounts of both scanner mirrors M1 and M2, the digital calculator 60a, which is the positioning determination means, determines the value of the deviation SAD output from the analog circuit 60d after reaching the settling range. Is read for each drive, and positioning is completed when the value of the deviation SAD enters the desired convergence range for a predetermined time or more. In this case, more time is required until the positioning is completed after entering the convergence range, but it is possible to automatically cope with a change in operating characteristics over time.
[0059]
FIG. 4 is a graph for explaining a specific operation of the laser drill machine of the embodiment. FIG. 4A shows a case where the drive angle is large, and FIG. Drive The case where the angle is small is shown. In the figure, the vertical axis represents the angles of the scanner mirrors M1, M2, and the horizontal axis represents time. Both figures show the target angles Caa, Cab, command values Cca, Ccb, operation characteristics Cda1, Cdb1 indicating changes in the current value of the first scanner mirror M1, and operation characteristics indicating changes in the current value of the second scanner mirror M2. Cda2 and Cdb2 are represented. It should be noted that the zone-shaped settling ranges and overshoots of the operation characteristics Cda1, Cdb1, Cda2, and Cdb2 are drawn larger than the actual ones for easy understanding.
[0060]
As is apparent from the figure, the convergence characteristics of the scanner mirrors M1 and M2 toward the target angles Caa and Cab usually vary depending on the size of the scanner mirror, and so on. Different for each scanner mirror M1, M2. For example, as shown in FIG. 4A, when the drive angle is large, the first scanner mirror M1 takes time A to converge, and the second scanner mirror M2 takes time B to converge. Further, the convergence characteristics of the scanner mirrors M1 and M2 change depending on the magnitude of the drive angle. For example, in the case of the first scanner mirror M1, the operating characteristic Cda1 when the driving angle is large requires time A to converge, and the operating characteristic Cdb1 when the driving angle is small requires time C to converge.
[0061]
In the galvano scanner 20 as described above, it is possible to set a uniform waiting time after reaching the settling range in accordance with the condition that requires the most time for positioning, and to determine that the positioning is completed after this waiting time. In the example shown in the figure, it is conceivable that the entire waiting time is the time B from the arrival in the settling range to the convergence, but the second scanner is in the case of a large drive angle from the settling range to the completion of positioning. In the case of the mirror M1, the time A ′, the case where the drive angle is small, the time C ′ in the case of the first scanner mirror M1, and the time D ′ in the case of the second scanner mirror M2 become the time to wait wastefully. . On the other hand, if the waiting time table Tw stored in the memory 60me shown in FIG. 3 is used, useless waiting times A ′, C ′, and D ′ do not occur.
[0062]
FIG. 5 is a graph for specifically explaining the operation in the third mode. In the figure, the vertical axis represents the angle of the scanner mirror, and the horizontal axis represents time. In the figure, the time change of the target angle Ca, the command value Cc, and the operating characteristic Cd of the scanner mirror is shown. When the characteristics of the galvano scanner 20 change over time due to continued use, the operation characteristic Cd becomes a characteristic Cdd1 having a large overshoot or a characteristic Cdd2 having a small follow-up speed. Further, there may be a characteristic Cdd3 held at an angle deviated from the command value Cc.
[0063]
For example, when the galvano scanner 20 detects that the operation characteristic Cdd1 has a large overshoot, the scanner control unit 60 corrects the command value Cc to a command value Ccc1 that rises relatively smoothly, and the galvano scanner 20 is changed. Make it work. Thereby, the operation of the galvano scanner 20 can be brought close to the operation characteristic Cd. When it is detected that the galvano scanner 20 has the operation characteristic Cdd2 having a small inclination, the scanner control unit 60 corrects the command value Cc to the command value Ccc2 having a large inclination and operates the galvano scanner 20. Further, when it is detected that the galvano scanner 20 has the operation characteristic Cdd3 having a target value deviation, the scanner control unit 60 corrects the command value Cc to a command value that cancels the target value and operates the galvano scanner 20. Let
[0064]
FIG. 6 is a diagram for specifically explaining the standby time table Tw used in the fourth mode. In this case, the temperature of the galvano scanner 20 is divided into four regions of 0 to A ° C., A to B ° C., B to C ° C., and C to C ° C. or more, and a standby time corresponding to the driving angle is set for each region. .
[0065]
According to this embodiment, since only the setting of the digital calculator is changed from the result of the machining experiment, difficult servo adjustment or the like is not required.
[0066]
Next, a second embodiment of the present invention will be described in detail.
[0067]
In the present embodiment, in the first mode with the first embodiment, the waiting time from when the digital computer 60a receives the settling range signal SD to when the positioning completion signal SRD is output to the host controller 80 is shown in FIG. As shown in FIG. 7, it is variable according to the target angle of the mirror corresponding to the processing position. In the case of the example shown in FIG. 9, at the machining position with poor machining accuracy, this waiting time is lengthened and the settling waiting time until machining is lengthened.
[0068]
In the first embodiment, the waiting time is changed according to the mirror driving angle (hole distance), and in the second embodiment, the waiting time is changed according to the mirror target angle (processing position). As in the embodiment, the standby time table is a three-dimensional table corresponding to both the mirror target angle (processing position) and the drive angle (hole distance), and the standby time is determined according to both the mirror target angle and the drive angle. It is also possible to change ae (for example, a <b <c <d <e).
[0069]
According to this embodiment, it is possible to perform better processing.
[0070]
Although the present invention has been described based on the above embodiments, the present invention is not limited to the above embodiments. For example, the galvano scanner apparatus according to the embodiment can be incorporated in various laser processing apparatuses including not only a laser drill machine but also a marking machine.
[0071]
In the above embodiment, the scanner control unit 60 is operated in the first to fifth modes. However, the scanner control unit 60 can be operated by appropriately combining the first to fifth modes. For example, the characteristic difference between the scanner mirrors M1 and M2 can be corrected in consideration of the temperature of the galvano scanner 20 during the operations in the second and third modes. Specifically, a coefficient multiplied by a standard waiting time or an offset to be added can be used as a function of time, or a waiting time table prepared in a large number according to a characteristic difference can include a temperature parameter.
[0072]
【The invention's effect】
According to the present invention, the standby time expected to be required to reach and hold the target angle after the driving position of the mirror reaches the settling range is determined according to the driving angle and target angle of the mirror. Since it is changed, processing such as a laser via with a high throughput can be performed with a small error by using the standby time.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating the structure of a laser drill machine incorporating an apparatus according to an embodiment.
2 is a block diagram mainly illustrating the circuit configuration of the scanner control unit in FIG. 1;
3 is a block diagram illustrating a circuit configuration of the digital calculator of FIG. 2;
FIG. 4 is a graph illustrating a specific operation of a laser drill machine
FIG. 5 is a graph for explaining a specific operation of the laser drill machine.
FIG. 6 is a diagram for explaining a modified example of a standby time table used for driving a laser drill machine.
FIG. 7 is a diagram illustrating an example of a relationship between a target angle of a mirror and a standby time in the second embodiment of the present invention.
FIG. 8 is a diagram showing an example of the relationship between the target angle and drive angle of the mirror and the standby time in the third embodiment.
FIG. 9 is a diagram for explaining a conventional problem.
[Explanation of symbols]
10 ... Laser oscillation device
20 ... Galvano scanner
21, 22 ... Mirror drive device
24, 25 ... Temperature sensor
30 ... fθ lens
50 ... Stage
60. Scanner control unit
60a ... Digital calculator
60d ... Analog circuit
60ad ... Judgment part
60cg ... Command value generator
60me ... memory
70: Stage control unit
80: Host controller
Cr: Standard characteristics
LB ... Laser beam
M1 ... 1st scanner mirror
M2 ... second scanner mirror
S1, S2 ... Angle sensor
Tw ... Standby time table
W ... Workpiece

Claims (15)

A galvano scanner device that moves an irradiation position of a laser beam by a mirror and a mirror driving device,
A settling range detecting means for detecting that the mirror drive position has reached a predetermined settling range including a target angle by the mirror driving device;
Control means for changing a waiting time, which is expected to be required to reach and hold the target angle after the driving position of the mirror reaches the settling range, according to the angle of the mirror;
A galvano scanner device comprising: The galvano scanner device according to claim 1, wherein the waiting time is changed according to a driving angle up to a target angle of the mirror. The galvano scanner device according to claim 1, wherein the waiting time is changed according to a target angle of the mirror. The galvano scanner device according to claim 1, wherein the waiting time is changed according to both a target angle of the mirror and a driving angle up to the target angle . The galvano scanner device according to any one of claims 1 to 4, further comprising a standby time table that stores the standby time in correspondence with an irradiation position of a laser beam . 6. The galvano scanner device according to claim 1, wherein the waiting time is set for each mirror scanning direction. 7. The galvano scanner device according to claim 1, further comprising waveform forming means for forming a command waveform for driving the mirror as digital data. 8. The apparatus according to claim 1, further comprising: an output unit that outputs a positioning completion signal after waiting until the operation of the mirror is completed based on the waiting time when reaching the settling range. The galvano scanner device described. 2. The standby time is set including a delay of an operation of a predetermined component that operates in relation to the operation of the mirror and at least a control device that controls the operation of the predetermined component. The galvano scanner device according to claim 8. A characteristic difference detecting means for obtaining a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving device with a reference characteristic, and the standby time based on the characteristic difference obtained by the characteristic difference detecting means. The galvano scanner device according to claim 1, further comprising correction means for correcting. The apparatus further comprises characteristic difference detection means for obtaining a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving device with a reference characteristic, and a plurality of the standby times are set according to the plurality of patterns of the characteristic difference. The galvano scanner device according to claim 1, wherein the galvano scanner device is stored as a waiting time table. The apparatus further comprises a characteristic difference detecting means for obtaining a characteristic difference by comparing a deviation or a current value of the driving position of the mirror by the mirror driving device with a reference characteristic, and the waveform forming means includes the characteristic obtained by the characteristic difference detecting means. The galvano scanner device according to claim 7, wherein a command waveform for driving the mirror is corrected in accordance with the difference. The galvano scanner device according to any one of claims 1 to 12, further comprising a temperature sensor for detecting a temperature in the vicinity of the mirror and the mirror driving device, and storing the standby time for each temperature. Positioning determination means for determining that positioning of the mirror is completed when the mirror enters a predetermined convergence range that is narrower than the settling range and includes the vicinity of the target angle for a predetermined time. A galvano scanner device according to any one of claims 1 to 13. A method of controlling a galvano scanner device that moves an irradiation position of a laser beam by a mirror and a mirror driving device,
Determining a standby time that is expected to be required to reach and hold the target angle after the driving position of the mirror reaches a predetermined settling range including a target angle, according to the angle of the mirror; ,
Detecting that the driving position of the mirror has reached the settling range by the mirror driving device;
And a step of outputting a positioning completion signal after waiting until the operation of the mirror is completed based on the waiting time.

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