JP6632781B1 - Laser processing apparatus, laser processing method, and error adjustment method - Google Patents

Abstract

A laser processing apparatus (100) includes a processing table (2A), a galvano scanner (5A) that drives a galvanometer mirror (4A), a camera (7A) that observes a surface of the processing table, and a processing work (3A). A control device (10) for controlling laser processing, a reference plate (8) on which a plurality of reference marks (M) are arranged is placed on the processing table (2A), and the control device (10) Based on the measurement positions (MQ) of the four or more reference marks (M), the positioning error of the processing table (2A) is calculated, and the camera (7A) and the processing table (2A) are linked to each other to obtain the reference mark. The controller (10) repeats the process of measuring (M), calculates the positioning error over the entire area of the processing table (2A), and performs laser processing of the processing target based on the calculated positioning error. To your.

Description

  The present invention relates to a laser processing apparatus, a laser processing method, and an error adjustment method for performing laser processing on a processing work placed on a processing table.

  The laser processing apparatus performs laser processing on various positions on the work by moving a work table on which the work is placed. Since the laser processing apparatus has a positioning error in the processing table, the laser processing apparatus needs to correct the irradiation position of the laser beam based on the positioning error.

  The laser processing apparatus described in Patent Document 1 is a camera that can observe a processing target surface via a galvano scanner, detects the position of a scale mark formed on a glass scale on the galvano scanner, and detects the position of the scale mark and the detection result. Thus, a correction value for correcting the driving amount of the galvano scanner is obtained.

JP 2008-264789 A

  However, in the technology of Patent Document 1, since the camera and the galvano scanner are not linked, the correction can be performed only in a range where the image of the processing target can be captured by the movement of the galvano scanner, and the processing table is wider than the galvano scan area. There is a problem that the correction cannot be performed on the upper processing target area.

  The present invention has been made in view of the above, and an object of the present invention is to provide a laser processing apparatus that can accurately process a processing target area on a processing table that is wider than a galvano scan area.

In order to solve the above-described problems and achieve the object, a laser processing apparatus according to the present invention includes a processing table on which a processing target is placed, a galvanometer mirror configured to irradiate a laser beam onto the processing target to scan, and a galvanometer. It comprises a galvanometer scanner for driving the mirror, a. The laser processing apparatus of the present invention measures four or more reference marks when a reference plate on which four or more reference marks are arranged in a rectangular area is placed on a processing table, and the processing object is processed. A measurement device is provided for measuring the position of an alignment mark provided on a processing surface of a processing target when the processing device is placed on a table. The laser processing apparatus of the present invention calculates a positioning error of the processing table and a correction coefficient for correcting the positioning error based on the measurement positions of the four or more reference marks, and corrects the measurement position of the alignment mark using the correction coefficient. Calculating a galvano scanner drive correction amount for correcting a positioning error based on the corrected alignment mark measurement position, and using the drive correction amount to drive the galvano scanner to perform laser processing on an object to be processed. And a control device for controlling the In the laser processing apparatus of the present invention, when the correction coefficient is calculated, the measurement device and the processing table are linked to each other, so that the processing of measuring four or more reference marks is repeated. The correction coefficient is calculated over the range .

  The laser processing apparatus according to the present invention has an effect that a processing target area on a processing table that is wider than a galvano scan area can be accurately processed.

FIG. 1 is a diagram showing a configuration of a laser processing apparatus according to an embodiment FIG. 2 is a diagram illustrating a configuration of a control device included in the laser processing apparatus according to the embodiment. 9 is a flowchart illustrating a correction coefficient calculation process performed by the laser processing apparatus according to the embodiment. FIG. 4 is a view for explaining a measurement area of a reference plate used in the laser processing apparatus according to the embodiment. FIG. 7 is a diagram for explaining reference marks measured by the laser processing apparatus according to the embodiment. FIG. 7 is a diagram for explaining a relationship between the actual position of the reference mark and the measurement position, which is acquired by the laser processing apparatus according to the embodiment 11 is a flowchart showing a procedure of calculating a galvano correction amount by the laser processing apparatus according to the embodiment. FIG. 4 is a diagram for explaining an alignment mark used by the laser processing apparatus according to the embodiment. FIG. 2 is a diagram illustrating an example of a hardware configuration of a control device according to the embodiment.

  Hereinafter, a laser processing apparatus, a laser processing method, and an error adjustment method according to an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

Embodiment.
FIG. 1 is a diagram illustrating a configuration of a laser processing apparatus according to an embodiment. The laser processing device 100 is a device that performs laser drilling on the work pieces 3A and 3B while correcting a positioning error of the work tables 2A and 2B on which the work pieces 3A and 3B to be processed are placed. The position correction of the processing tables 2A and 2B by the laser processing apparatus 100 is effective for performing the processing in conjunction with the galvano scanners 5A and 5B and the processing tables 2A and 2B.

  The laser processing apparatus 100 places a reference plate for measuring a positioning error on the processing tables 2A and 2B, and measures the position of a reference mark arranged on the reference plate. The reference plate is a plate on which the position of the reference mark is measured while being placed on the processing tables 2A and 2B. The laser processing apparatus 100 calculates the positioning error of the processing tables 2A and 2B based on the difference between the actual position of the reference mark and the measurement position of the reference mark, and calculates a correction coefficient for correcting the positioning error. . The actual position of the fiducial mark is the designed position (design value) of the fiducial mark, and the measured position of the fiducial mark is the position of the fiducial mark measured with the fiducial plate placed on the processing tables 2A and 2B. It is.

  The laser processing apparatus 100 repeats the process of measuring the reference mark by linking the cameras 7A and 7B with the processing tables 2A and 2B, and calculates the correction coefficient over the entire area of the processing tables 2A and 2B. The correction coefficient is used when correcting the positions of the processing tables 2A and 2B. The laser processing apparatus 100 corrects the positions of the processing tables 2A and 2B by correcting the positions of the alignment marks arranged on the processing workpieces 3A and 3B on the processing tables 2A and 2B with a correction coefficient. The alignment mark is a mark whose position is measured in a state where the work pieces 3A and 3B are placed on the work tables 2A and 2B, and is used when correcting the position of the work pieces 3A and 3B. Details of the alignment mark will be described later.

  The laser processing apparatus 100 includes a processing mechanism 20 that performs laser processing on the processed workpieces 3A and 3B, and a control device 10 that controls the processing mechanism 20. The control device 10 calculates a correction coefficient using least square approximation or the like for each measurement area where the reference mark is arranged. The control device 10 creates a calibration table indicating the correspondence between the correction coefficient and the measurement area. The calibration table is a table for correcting a positioning error of the processing tables 2A and 2B. When controlling the laser processing, the control device 10 extracts a correction coefficient for each measurement area based on the calibration table, and applies the extracted correction coefficient to each measurement area to irradiate the laser beams 1A and 1B. Correct the position.

  The processing mechanism 20 separates a laser beam (laser beam) output from a laser oscillator (not shown) into laser beams 1A and 1B on an optical path and simultaneously processes the workpieces 3A and 3B on the processing tables 2A and 2B. Process.

  The processing mechanism 20 includes a first processing unit that irradiates the processing work 3A with the laser light 1A and a second processing unit that irradiates the processing work 3B with the laser light 1B. The first processing unit includes a galvanometer scanner 5A, a galvanometer mirror 4A, a camera 7A, an fθ lens 6A, and a processing table 2A, and the second processing unit includes a galvanometer scanner 5B, a galvanometer mirror 4B, a camera 7B, an fθ lens 6B, and a processing table 2B.

  Further, the processing mechanism 20 includes a drive table 21 that drives the processing tables 2A and 2B. The processing tables 2A and 2B are XY processing tables that can move in an XY plane such as a horizontal plane. The working tables 2A and 2B move the work pieces 3A and 3B in the XY plane by moving in the X-axis direction and the Y-axis direction, respectively, whereby the laser beams 1A and 1B are transferred onto the work pieces 3A and 3B. Adjust the irradiation position.

  The processing table 2A fixes the processing work 3A on the processing table 2A by sucking the processing work 3A, and the processing table 2B fixes the processing work 3B on the processing table 2B by suctioning the processing work 3B. As described above, the processing mechanism 20 is configured such that the two processing tables 2A and 2B are attached to the drive table 21 and can simultaneously process the two processed workpieces 3A and 3B.

  The processing tables 2A and 2B are both mounted on the drive table 21, but the positioning error of the processing table 2A is different from the positioning error of the processing table 2B. Therefore, the control device 10 separately calculates a correction coefficient for the processing table 2A and a correction coefficient for the processing table 2B.

  Note that the processing mechanism 20 may be a processing mechanism that performs laser processing on one processing workpiece with one laser light without separating the laser light. That is, the processing mechanism 20 may be a processing mechanism having one of the first processing unit and the second processing unit. Since the first processing unit and the second processing unit perform the same operation with the same configuration, the configuration and operation of the first processing unit will be described below.

  The galvano scanner 5A positions the irradiation position of the laser beam 1A at a high speed at a processing target position on the processing workpiece 3A. The galvano scanner 5A includes a galvanometer mirror 4A, a servomotor (not shown) for driving the galvanometer mirror 4A, and a drive control device (not shown) for controlling the drive of the servomotor. In the galvano scanner 5A, the drive control device drives the galvanometer mirror 4A, and the galvanometer mirror 4A scans the workpiece 3A with the laser light 1A from the laser oscillator.

  In the galvano scanner 5A, the drive control device rotates, for example, the galvanometer mirror 4A within a specific swing angle range. The galvano scanner 5A receives a command from the control device 10 and moves the irradiation position of the laser light 1A so that the target processing position in the scan area is irradiated with the laser light 1A. As described above, in the galvano scanner 5A, the drive control device drives the galvanometer mirror 4A so that the laser beam 1A is applied to a specific position in each scan area on the processing surface of the processing workpiece 3A. The scan area is an area scanned by the galvanomirror 4A. The scan area corresponds to a drivable area of the galvano scanner 5A. After the laser beam 1A is irradiated, the galvano scanner 5A repeats the operation of moving the irradiation position of the laser beam 1A to the next target position and stopping.

  The first processing unit has two galvanometer scanners 5A and two galvanometer mirrors 4A. In the first processing section, the irradiation position of the laser beam 1A on the processing work 3A is moved in the X-axis direction by rotating the galvanometer mirror 4A of the one galvano scanner 5A. In the first processing unit, the irradiation position of the laser beam 1A on the processing work 3A is moved in the Y-axis direction by rotating the galvanomirror 4A of the other galvano scanner 5A. The laser beam 1A reflected by one galvanometer mirror 4A is sent to the other galvanometer mirror 4A, and is reflected by the other galvanometer mirror 4A. The laser beam 1A reflected by the other galvanometer mirror 4A is applied to the work 3A.

  lens 6A focuses laser beam 1A on work 3A placed on work table 2A. The camera 7A, which is a measuring device, observes the surface of the processing table 2A and measures the positions of various marks. When calculating the correction coefficient, the camera 7A detects the position (coordinate) of the reference mark arranged on the reference plate on the processing table 2A. When the processing work 3A is placed on the processing table 2A, the camera 7A detects the position (coordinates) of the alignment mark arranged on the processing work 3A.

  The alignment mark is a mark for correcting the position of the work 3A. The workpiece 3A placed on the processing table 2A may be displaced due to distortion, expansion and contraction, or the like. The laser processing apparatus 100 detects the position of the alignment mark, and corrects the coordinates in the processed work 3A based on the position of the alignment mark and the correction coefficient.

  The camera 7A sends the control device 10 the position of the reference mark, which is the detection result of the reference mark, and the position of the alignment mark, which is the detection result of the alignment mark.

  In the laser processing apparatus 100, a laser beam 1A from a laser oscillator is applied to a scan area of a processing work 3A via a galvano mirror 4A attached to each axis and an fθ lens 6A.

  Since the area of the work 3A is larger than the area of the scan area, the laser processing apparatus 100 moves the processing table 2A from the scan area to the next scan area, and changes the irradiation position of the laser beam 1A in the scan area to a galvano scanner. Move at 5A. That is, the laser processing apparatus 100 moves the irradiation position of the laser light 1A between the scan areas by the processing table 2A, and moves the irradiation position of the laser light 1A within the scan area by the galvano scanner 5A. The laser processing apparatus 100 irradiates the laser beam 1A in each scan area, thereby performing laser processing on the entire processing area of the processing work 3A. That is, the laser processing apparatus 100 is configured to process the entire area of the processed workpiece 3A by repeating the processing of moving the processing table 2A to each scan area and the processing of irradiating the laser light 1A in each scan area. ing.

  The control device 10 is a computer that controls the processing mechanism 20. The control device 10 controls the driving of the processing table 2A, the laser oscillator, the galvano scanners 5A and 5B, and the like. The control device 10 of the embodiment calculates a calibration table based on information sent from the processing mechanism 20, and corrects a positioning error of the processing table 2A using the calibration table. The control device 10 corrects the position of the processed workpiece 3A using the correction coefficient stored in the calibration table, and corrects the drive amount of the galvano scanner 5A based on the corrected position. The control device 10 corrects the position of the galvanomirror 4A by correcting the driving amount of the galvano scanner 5A, and thereby corrects the irradiation position of the laser beam 1A.

  Here, the configuration of the control device 10 will be described. FIG. 2 is a diagram illustrating a configuration of a control device included in the laser processing apparatus according to the embodiment. The control device 10 includes an input unit 11, a correction coefficient calculation unit 12, a storage unit 13, a correction amount calculation unit 14, and a control unit 15.

  The input unit 11 receives the position of the reference mark sent from the camera 7A of the processing mechanism 20 and inputs the position to the control unit 15. Hereinafter, the position of the reference mark sent from the camera 7A is referred to as a measurement position. The input unit 11 receives the position of the alignment mark sent from the camera 7A of the processing mechanism 20 and inputs the position to the correction amount calculation unit 14.

  The correction coefficient calculation unit 12 reads from the storage unit 13 information indicating the correspondence between the actual position of the reference mark arranged in each measurement area of the reference plate and the measurement area. Further, the correction coefficient calculation unit 12 reads out information indicating the correspondence between the measurement position of the reference mark and the measurement area from the storage unit 13.

  The position of the measurement area of the reference plate corresponds to the position of the processing table 2A. The actual position of the reference mark is a design value. Hereinafter, the actual position of the reference mark is referred to as an actual position, and information indicating the correspondence between the actual position and the measurement area is referred to as actual position information. Information indicating the correspondence between the measurement position and the measurement area is referred to as measurement position information.

  The correction coefficient calculator 12 calculates a difference between the actual position and the measured position based on the actual position information and the measured position information. The correction coefficient calculation unit 12 calculates a correction coefficient for correcting the position of the measurement area based on the difference between the actual position and the measurement position. The correction coefficient calculation unit 12 calculates a correction coefficient for each measurement area, and sends information indicating the correspondence between the correction coefficient and the measurement area to the storage unit 13. Hereinafter, information indicating the correspondence between the correction coefficient and the measurement area is referred to as correction coefficient information.

  The storage unit 13 stores the actual position information. The storage unit 13 stores the measurement position information sent from the control unit 15. The storage unit 13 stores the correction coefficient information sent from the correction coefficient calculation unit 12.

  The correction amount calculation unit 14 reads the correction coefficient information from the storage unit 13. The correction amount calculation unit 14 corrects the position (coordinate) of the alignment mark using the correction coefficient information. Specifically, the correction amount calculation unit 14 specifies a measurement area corresponding to the position of the alignment mark, and extracts a correction coefficient corresponding to the specified measurement area from the correction coefficient information. The correction amount calculation unit 14 corrects the position of the alignment mark using the extracted correction coefficient. The position of the alignment mark corrected using the correction coefficient is an accurate position of the alignment mark in consideration of a position error of the processing table 2A, a position shift of the processed work 3A, and the like. Therefore, the correction amount calculation unit 14 calculates the difference between the position of the processing table 2A and the drive correction amount for correcting the drive amount of the galvano scanner 5A (hereinafter, referred to as a galvano correction amount) based on the corrected position of the alignment mark. A mathematical expression indicating the correspondence is calculated. This formula is a formula that can obtain the galvano correction amount corresponding to the coordinates on the processing table 2A by substituting the X coordinate and the Y coordinate on the processing table 2A. The coordinates (X coordinate and Y coordinate) of the processing table 2A are the center coordinates of the scan area by the galvano scanner 5A.

  The correction amount calculation unit 14 calculates a galvano correction amount corresponding to the position based on the position of the processing table 2A specified by the processing program. The correction amount calculation unit 14 sends the calculated galvano correction amount to the control unit 15.

  The control unit 15 controls the processing mechanism 20. The control unit 15 sends a drive instruction to the galvano scanner 5A, the processing table 2A, and the like. When calculating the correction coefficient information, the control unit 15 moves the imaging table of the camera 7A to the position of the reference mark arranged in the measurement area by moving the processing table 2A. The imaging position of the camera 7A is the center position of the scan area. The control unit 15 generates measurement position information in which a measurement area corresponding to the imaging position of the camera 7A is associated with an actual position transmitted from the input unit 11. The real position sent from the input unit 11 is a real position measured in a measurement area corresponding to the imaging position of the camera 7A. The control unit 15 sends the measurement position information to the storage unit 13.

  When driving the galvano scanner 5A, the control unit 15 corrects the driving amount of the galvano scanner 5A using the galvano correction amount for each table position that is the position of the processing table 2A. The control unit 15 sends a driving instruction in which the driving amount of the galvano scanner 5A is corrected to the processing mechanism 20. Thereby, the swing angle of the galvanometer mirror 4A is corrected, so that the irradiation position of the laser beam 1A is corrected.

  As described above, the control device 10 of the embodiment calculates the galvano correction amount for correcting the positioning error of the processing table 2A using the measurement position of the reference mark, and controls the galvano scanner 5A using the galvano correction amount. Drive.

  Next, a description will be given of a processing procedure of calculating a correction coefficient by the laser processing apparatus 100. FIG. 3 is a flowchart illustrating the procedure of calculating a correction coefficient by the laser processing apparatus according to the embodiment. FIG. 4 is a diagram for explaining a measurement area of a reference plate used in the laser processing apparatus according to the embodiment. FIG. 5 is a diagram for explaining reference marks measured by the laser processing apparatus according to the embodiment.

  When calculating the correction coefficient, the laser processing apparatus 100 measures the position of the reference mark M with the position correction of the processing table 2A disabled, and calculates the correction coefficient based on the measured position. This is because when the position correction is enabled, the positional deviation of the reference mark M cannot be measured. Therefore, when the position correction of the processing table 2A is valid, the control device 10 of the laser processing apparatus 100 invalidates the position correction of the processing table 2A (step S1). That is, when the setting for correcting the drive amount of the galvano scanner 5A is valid, the laser processing apparatus 100 invalidates the setting for correcting the drive amount of the galvano scanner 5A.

  A reference plate 8 serving as a reference for creating a calibration table is placed on the processing table 2A. The reference plate 8 has a plurality of reference marks M printed at equal intervals on the upper surface of the reference plate 8. The reference marks M are arranged in a grid in an area that can cover the entire surface of the processing table 2A. The reference mark M may be arranged on the upper surface of the reference plate 8 by a method other than printing. Further, the reference marks M may be arranged in a shape other than the lattice shape. The reference plate 8 is a quartz glass plate or the like having a good arrangement accuracy of the reference mark M. In the laser processing apparatus 100, the reference plate 8 is used as a master scale of the processing table 2A, that is, a reference scale.

  As shown in FIG. 4, a plurality of measurement areas such as a measurement area 30n and a measurement area 30 (n + 1) are provided on the entire surface of the reference plate 8. Here, n is a natural number. Since each measurement area set on the reference plate 8 has the same shape and size, the measurement area 30n will be described below. The measurement area 30n is a rectangular area in which fiducial marks M are arranged at each of four vertices. In FIG. 5, four reference marks M in the measurement area 30n are illustrated by reference marks P1 to P4. As for the measurement area on the reference plate 8, the more the number of areas, that is, the narrower each measurement area, the more accurate the displacement can be corrected.

  The reference plate 8 is formed using, for example, a plate-like member having an X-axis direction of 800 mm and a Y-axis direction of 600 mm. An example of the scan area corresponding to the operable area of the galvano scanner 5A is 30 mm × 30 mm.

  In the reference plate 8, the measurement areas adjacent to each other share two reference marks M (one side which is a line segment area between the two reference marks M). For example, the measurement area 30 (n + 1) adjacent to the measurement area 30n and the measurement area 30n share two reference marks M. Specifically, the reference marks P3 and P4 are reference marks arranged on the right side of the measurement area 30n and are reference marks arranged on the left side of the measurement area 30 (n + 1). Similarly, the lower side of the measurement area 30n is shared by other measurement areas. As described above, the adjacent measurement areas share one side, so that the measurement areas are set in the reference plate 8 in a lattice shape.

  The laser processing apparatus 100 performs a process of moving the imaging position of the camera 7A onto the reference mark Pm in the measurement area 30n, a process of measuring the position of the reference mark Pm, and a process of storing measurement data, where m = 1 to 4. Repeat until Specifically, the control unit 15 moves the processing table 2A to a table position where the imaging position of the camera 7A is on the reference mark P1 in the measurement area 30n. The imaging position of the camera 7A is a position on the reference plate 8 at which the camera 7A captures an image. That is, the laser processing apparatus 100 moves the processing table 2A on which the reference plate 8 is placed in a plane parallel to the table surface of the processing table 2A, so that the imaging position of the camera 7A is positioned on the reference mark P1 of the measurement area 30n. (Step S2).

  The laser processing device 100 measures the position of the reference mark P1 with the camera 7A (Step S3). In FIG. 5, a measurement position as a measurement result of the reference mark P1 is illustrated by a measurement position Q1. The laser processing device 100 sends the measurement position Q1 to the control device 10. Thereby, the laser processing apparatus 100 stores the measurement data (Step S4). Specifically, the laser processing apparatus 100 associates the measurement area 30n with the measurement position Q1 of the reference mark P1 and stores it in the storage unit 13.

  The laser processing device 100 determines whether or not the position has been measured from the reference mark P1 to the reference mark P4 (step S5). When the position has not been measured up to the reference mark P4 (Step S5, No), the laser processing apparatus 100 repeats the processing from Step S2 to Step S5. That is, the laser processing apparatus 100 repeats the processing from step S2 to step S5 until the position of the reference mark P4 is measured (until m = 4).

  That is, the laser processing apparatus 100 moves the processing table 2A to the position of the reference mark P2 (Step S2), measures the position of the reference mark P2 (Step S3), and uses the measurement area 30n and the measurement result of the reference mark P2. It is stored in the storage unit 13 in association with a certain measurement position Q2 (step S4).

  Similarly, the laser processing apparatus 100 moves the processing table 2A to the position of the reference mark P3 (Step S2), measures the position of the reference mark P3 (Step S3), and measures the measurement area 30n and the measurement result of the reference mark P3. Is stored in the storage unit 13 in association with the measurement position Q3 (step S4).

  Similarly, the laser processing apparatus 100 moves the processing table 2A to the position of the reference mark P4 (Step S2), measures the position of the reference mark P4 (Step S3), and measures the measurement area 30n and the measurement result of the reference mark P4. Is stored in the storage unit 13 in association with the measurement position Q4 (step S4). As described above, the reference mark is sequentially moved to the measurement position by the camera 7A by moving the processing table 2A. Information in which the measurement area 30n is associated with the measurement positions Q1 to Q4 is the measurement position information.

  When the position is measured up to the reference mark P4 (Step S5, Yes), the correction coefficient calculation unit 12 reads the actual position information and the measured position information from the storage unit 13, and determines the actual position and the actual position based on the actual position information and the measured position information. The difference from the measurement position is calculated. The correction coefficient calculation unit 12 calculates a correction coefficient for each measurement area based on the difference between the actual position and the measurement position, and stores the correction coefficient in the storage unit 13 (Step S6). At this time, the correction coefficient calculation unit 12 calculates a correction coefficient by least square approximation using the four actual positions of the reference marks P1 to P4 and the four measurement positions Q1 to Q4 that are the measurement positions. Specifically, the correction coefficient calculation unit 12 calculates a correction coefficient by applying least square approximation to the difference between the four actual positions and the four measurement positions Q1 to Q4. Further, the correction coefficient calculation unit 12 may calculate the correction coefficient for the table position in the measurement area 30n by performing the parallelogram correction or the trapezoid correction in addition to the calculation of the correction coefficient.

  Note that the camera 7A is not limited to measuring the positions of the four reference marks P1 to P4 in the measurement area 30n, but may measure the positions of the reference marks at five or more positions. That is, four or more (at least four) reference marks may be arranged in the measurement area 30n. In this case, the camera 7A measures four or more reference marks in the measurement area 30n, and the correction coefficient calculation unit 12 calculates the correction coefficients using the measurement position information of the four or more reference marks. Here, the positions of the four or more reference marks are measured because the correction coefficients in the X-axis direction and the Y-axis direction can be easily and accurately calculated if the positions of the four or more reference marks are known. It is.

  The control unit 15 determines whether the correction coefficients have been calculated for all the measurement areas (Step S7). If there is a measurement area for which the correction coefficient has not been calculated (No at Step S7), the laser processing apparatus 100 performs the processing from Step S2 to Step S6 for the measurement area for which the correction coefficient has not been calculated according to the instruction from the control unit 15. Execute the processing of The laser processing apparatus 100 executes the processing from step S2 to step S6 for each measurement area until the correction coefficients have been calculated for all the measurement areas. When there is no more measurement area for which the correction coefficient has not been calculated (Step S7, Yes), the laser processing apparatus 100 ends the correction coefficient calculation process.

  The correction coefficient calculation unit 12 creates a calibration table indicating the correspondence between the correction coefficients and the measurement areas, using the calculated correction coefficients for all the measurement areas. When calculating the correction coefficient in each measurement area by performing the parallelogram correction or the trapezoid correction, the correction coefficient calculation unit 12 also performs the calibration table with high accuracy on the table positions between the reference marks in the measurement area 30n. Can be created.

  FIG. 6 is a diagram for explaining the relationship between the actual position of the reference mark and the measurement position, which is acquired by the laser processing apparatus according to the embodiment. FIG. 6 shows the correspondence between the actual position AP of the reference mark M arranged on the reference plate 8 and the measurement position MQ. In FIG. 6, the difference between the actual position AP and the measurement position MQ is shown as 1000 times. The actual position AP is arranged on the entire surface of the reference plate 8, and the laser processing apparatus 100 measures the measurement position MQ for each actual position AP. The measurement position MQ overlapping the real position AP is the measurement position MQ corresponding to the real position AP. When the reference plate 8 is fixed to the processing table 2A with reference to the reference point BP at the upper left position in the entire area of the reference plate 8, the distance between the reference point BP and the reference position and the actual position increases as the distance from the reference point BP increases. The difference (error) between them increases.

  After calculating the correction coefficient information, the laser processing apparatus 100 calculates the galvano correction amount, and performs the laser processing of the processing work 3A using the galvano correction amount. Here, the procedure of calculating the galvano correction amount by the laser processing apparatus 100 will be described.

  FIG. 7 is a flowchart illustrating a procedure of a galvano correction amount calculation process performed by the laser processing apparatus according to the embodiment. The laser processing apparatus 100 starts processing the processing work 3A with the reference plate 8 removed from the processing table 2A and the processing work 3A placed on the processing table 2A.

  The laser processing apparatus 100 enables the position correction of the processing table 2A (step S11). The laser processing apparatus 100 moves the imaging position of the camera 7A to the position of the alignment mark of the processing work 3A (Step S12). That is, the laser processing apparatus 100 moves the imaging position of the camera 7A to a table position corresponding to the alignment mark by moving the processing table 2A. The camera 7A measures the position of the alignment mark (Step S13).

  FIG. 8 is a diagram for explaining an alignment mark used by the laser processing apparatus according to the embodiment. FIG. 8 shows the work 3A when the work 3A placed on the work table 2A is viewed from the upper surface side. Alignment marks 9 are arranged at or near the positions of the four vertices of the processed workpiece 3A.

  The camera 7 </ b> A sends the position of the alignment mark 9, which is the measurement result of the alignment mark 9, to the control device 10. The correction amount calculation unit 14 of the control device 10 calculates an alignment correction amount based on the position of the alignment mark 9 and the correction coefficient information and applies the correction amount to the position of the alignment mark 9 (Step S14). The alignment correction amount is a correction amount for correcting the position of the alignment mark 9.

  The control unit 15 determines whether the alignment correction amount has been calculated for all the alignment marks 9 (Step S15). When there is an alignment mark 9 for which the alignment correction amount has not been calculated (step S15, No), the laser processing apparatus 100 performs a step for the alignment mark 9 for which the alignment correction amount has not been calculated in accordance with an instruction from the control unit 15. The processing from step S12 to step S14 is executed. The laser processing apparatus 100 executes the processing from step S12 to step S14 for each measurement area until the alignment correction amount is calculated for all the alignment marks 9. When there is no alignment mark 9 for which the alignment correction amount has not been calculated (step S15, Yes), the correction amount calculation unit 14 determines the galvano correction amount at the time of laser processing of each table position based on the calculated plurality of alignment correction amounts. Is calculated (step S16).

  As described above, the control device 10 calculates the positioning error of the processing table 2A in each measurement area based on the measurement position MQ of the reference mark, calculates the correction coefficient for correcting the positioning error based on the positioning error, and calculates the correction coefficient. Is used to correct the position of the alignment mark 9, and a galvano correction amount is calculated based on the corrected position of the alignment mark 9.

  The correction amount calculation unit 14 calculates a galvano correction amount for each table position, and the control unit 15 executes laser processing while correcting the drive amount of the galvano scanner 5A using the galvano correction amount for each table position. Thereby, the swing angle of the galvanomirror 4A is corrected for each table position, so that the irradiation position of the laser beam 1A is corrected for each table position. Since the correction of the irradiation position of the laser beam 1A is a correction corresponding to a positioning error of the processing table 2A, the laser processing apparatus 100 corrects the positioning error of the processing table 2A for each table position, and then processes the processing work 3A. Laser processing can be performed.

  According to the present embodiment, the positioning accuracy of the processing table 2A has been improved from 13.33 μm to 6.46 μm. That is, while the positioning error when the positioning error of the processing table 2A was not corrected was 13.33 μm, the laser processing apparatus 100 corrected the positioning error of the processing table 2A using the reference plate 8. The positioning error was 6.46 μm.

  Further, according to the present embodiment, the positioning accuracy of the processing table 2B has been improved from 11.65 μm to 7.62 μm. That is, while the positioning error when the positioning error of the processing table 2B was not corrected was 11.65 μm, the laser processing apparatus 100 corrected the positioning error of the processing table 2B using the reference plate 8. The positioning error was 7.62 μm.

  The processing table 2A has a squareness or straightness that depends on the processing accuracy of the processing table 2A itself. Therefore, when the processing table 2A is moved, not only one-dimensional displacement for each moving axis but also two-dimensional displacement (rotational displacement) occurs. In the present embodiment, the correction coefficient is calculated by least squares approximation for the measurement area 30n using the four actual positions of the reference marks P1 to P4 and the four measurement positions Q1 to Q4. It is possible to correct the two-dimensional displacement of the 2A movement.

  In the present embodiment, the calibration table for correcting the positioning error of the processing table 2A is created by moving the processing table 2A without driving the galvano scanner 5A. For this reason, it is possible to obtain a correction coefficient that can make the positioning error of the processing table 2A at the actual position AP of the reference mark M close to 0 by one table creation. Therefore, the time required to create the calibration table can be reduced, and the accuracy of correction of the positioning error can be improved, so that efficient and high-precision laser processing can be realized.

  In addition, by performing the parallelogram correction or the trapezoid correction, a correction coefficient can be obtained even for the table position in the measurement area 30n. The error can be corrected.

  Here, a hardware configuration of the control device 10 will be described. FIG. 9 is a diagram illustrating an example of a hardware configuration of a control device according to the embodiment. The control device 10 can be realized by the processor 301, the memory 302, and the interface circuit 303 illustrated in FIG. The processor 301, the memory 302, and the interface circuit 303 can transmit and receive data to and from each other via a bus. Examples of the processor 301 are a CPU (Central Processing Unit, central processing unit, processing unit, arithmetic unit, microprocessor, microcomputer, processor, DSP (Digital Signal Processor)) or system LSI (Large Scale Integration). Examples of the memory 302 are a RAM (Random Access Memory) or a ROM (Read Only Memory).

  The control device 10 is realized by the processor 301 reading and executing a program for executing the operation of the control device 10 stored in the memory 302. It can also be said that this program causes a computer to execute the procedure or method of the control device 10. The memory 302 is also used as a temporary memory when the processor 301 executes various processes.

  The program executed by the processor 301 may be a computer program product having a computer-readable non-transitory recording medium including a plurality of instructions for performing data processing, which can be executed by a computer. . A program executed by the processor 301 causes a computer to execute a plurality of instructions to perform data processing.

  Further, the control device 10 may be realized by dedicated hardware. Further, some of the functions of the control device 10 may be realized by dedicated hardware, and some may be realized by software or firmware.

  In the present embodiment, the processing mechanism 20 separates the laser light into two laser lights 1A and 1B and performs laser processing on the two processing works 3A and 3B simultaneously on the two processing tables 2A and 2B. However, the configuration of the processing mechanism 20 is not limited to this configuration. The processing mechanism 20 may be configured to process a plurality of workpieces with one processing table, or may be configured to process a plurality of workpieces by attaching a plurality of processing tables to a plurality of drive systems. .

  As described above, according to the embodiment, the positioning error of the processing table 2A is calculated based on the measurement positions of the four or more reference marks, and the camera 7A and the processing table 2A are linked to measure the reference mark. Is repeated, and the positioning error is calculated over the entire area of the processing table 2A, so that the galvano scanner 5A can handle (a range in which an image of a processing target can be captured by the movement of the galvano scanner 5A), that is, the galvano scan area. The galvano correction amount for the positioning error can be calculated for a large processing target area. Therefore, a processing target area larger than the range that the galvano scanner 5A can handle can be processed with high accuracy. Further, the positioning error of the processing table 2A is calculated based on the measurement positions MQ of the four or more reference marks M, and the galvano correction amount is calculated based on the positioning error. Therefore, the accuracy corresponding to the positioning error of the processing table 2A is calculated. Can be calculated in a short time. Therefore, highly accurate processing can be realized in a short time.

  The configurations described in the above embodiments are merely examples of the contents of the present invention, and can be combined with other known technologies, and can be combined with other known technologies without departing from the gist of the present invention. Parts can be omitted or changed.

  1A, 1B laser beam, 2A, 2B processing table, 3A, 3B processing work, 4A, 4B galvanometer mirror, 5A, 5B galvano scanner, 6A, 6B fθ lens, 7A, 7B camera, 8 reference plate, 9 alignment mark, 10 Control device, 11 input unit, 12 correction coefficient calculation unit, 13 storage unit, 14 correction amount calculation unit, 15 control unit, 20 processing mechanism, 21 drive table, 30n, 30 (n + 1) measurement area, 100 laser processing device, AP Actual position, BP reference point, M, P1 to P4 reference mark, MQ, Q1 to Q4 measurement position.

Claims (7)

A processing table on which the processing object is placed,
A galvanomirror that scans by irradiating the object with laser light,
A galvano scanner that drives the galvanometer mirror,
When a reference plate on which four or more reference marks are arranged in a rectangular area is placed on the processing table, the four or more reference marks are measured, and the workpiece is placed on the processing table. A measuring device that measures the position of an alignment mark provided on a processing surface of the processing target when
Calculating a positioning error of the processing table and a correction coefficient for correcting the positioning error based on the measurement positions of the four or more reference marks, correcting the measurement position of the alignment mark using the correction coefficient, and correcting Calculating a drive correction amount of the galvano scanner for correcting the positioning error, based on the measured position of the alignment mark, and driving the galvano scanner using the drive correction amount to thereby process the workpiece. A control device for controlling the laser processing of the
With
When calculating the correction coefficient, by interlocking the measuring device and the processing table, the processing of measuring the four or more reference marks is repeated, and the control device performs the processing over the entire area of the processing table. Calculating a correction coefficient ,
A laser processing apparatus characterized by the above-mentioned. The control device calculates the drive correction amount using a positioning error of a rectangular area corresponding to the position of the alignment mark among the positioning errors,
The laser processing apparatus according to claim 1 , wherein: The control device applies least square approximation to the difference between the actual position of the reference mark and the measurement position to calculate the positioning error of the rectangular area,
The laser processing apparatus according to claim 1, wherein: The control device calculates a positioning error in the rectangular area by parallelogram correction or trapezoid correction,
The laser processing apparatus according to claim 3 , wherein: The rectangular area is adjacent to an adjacent rectangular area and shares an adjacent side,
The laser processing apparatus according to any one of claims 1 to 4 , wherein: A processing table on which a processing target is placed, a galvanometer mirror that scans the processing target by irradiating a laser beam, a galvano scanner that drives the galvanometer mirror, and a measurement device that observes the surface of the processing table. And a control device for controlling the laser processing of the object to be processed. A reference plate having four or more reference marks arranged in a rectangular area is placed on the processing table with respect to the laser processing device. Placing step;
A first measurement step in which the measurement device measures the four or more reference marks;
Wherein the controller, a first calculation step of calculating a correction coefficient based on the measured positions of the reference marks or the four points, to correct the positioning error and the positioning error of the machining table,
A second measurement step of measuring the position of an alignment mark provided on a processing surface of the processing object while the processing object is placed on the processing table;
The control device, a correction step of correcting the measurement position of the alignment mark using the correction coefficient,
A second calculation step of calculating a drive correction amount of the galvano scanner, wherein the control device calculates a correction amount of the galvano scanner based on the corrected measurement position of the alignment mark;
A control step of controlling the laser processing of the processing object while driving the galvano scanner using the drive correction amount,
Including
When calculating the correction coefficient, by linking the measuring device and the processing table, the process of measuring the reference mark is repeated, and the control device calculates the correction coefficient over the entire area of the processing table. Do
A laser processing method characterized by the above-mentioned. A processing table on which a processing target is placed, a galvanometer mirror that scans the processing target by irradiating a laser beam, a galvano scanner that drives the galvanometer mirror, and a measurement device that observes the surface of the processing table. And a control device for controlling the laser processing of the object to be processed. A reference plate having four or more reference marks arranged in a rectangular area is placed on the processing table with respect to the laser processing device. Placing step;
A first measurement step in which the measurement device measures the four or more reference marks;
Wherein the controller, a first calculation step of calculating a correction coefficient based on the measured positions of the reference marks or the four points, to correct the positioning error and the positioning error of the machining table,
A second measurement step of measuring the position of an alignment mark provided on a processing surface of the processing object while the processing object is placed on the processing table;
The control device, a correction step of correcting the measurement position of the alignment mark using the correction coefficient,
A second calculation step of calculating a drive correction amount of the galvano scanner, wherein the control device calculates a correction amount of the galvano scanner based on the corrected measurement position of the alignment mark;
A control step of controlling the laser processing of the processing object while driving the galvano scanner using the drive correction amount,
Including
When calculating the correction coefficient, by linking the measuring device and the processing table, the process of measuring the reference mark is repeated, and the control device calculates the correction coefficient over the entire area of the processing table. And
The control device, when controlling the laser processing of the processing target, corrects the positioning error with the correction coefficient ,
An error adjusting method, characterized in that:

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