TWI787595B - Laser processing apparatus, laser processing method and error adjusting method - Google Patents

Abstract

A laser processing apparatus (100) includes a control device (10), and repeats the process of interlocking a camera (7A) and a processing table (2A) to thereby measuring four or more reference marks to calculate a correction coefficient when the correction coefficient is to be calculated, wherein the control device (10) calculates a positioning error and the correction coefficient of the processing table (2A) based on the measurement positions of four or more reference marks, calculates a driving correction amount based on the measurement position of an alignment mark of a processed workpiece (3A) which has been corrected with the correction coefficient, and controls laser processing of the processing workpiece (3A) while driving a galvano scanner (5A) by using the drive correction amount.

Description

Laser processing device, laser processing method, and error adjustment method

The present invention relates to a laser processing device, a laser processing method and an error adjustment method for performing laser processing of a processed workpiece placed on a processing table.

The laser processing device performs laser processing on various positions on the workpiece by moving the processing platform on which the workpiece is placed. Since the processing platform in the laser processing device has a positioning error, the laser processing device must correct the irradiation position of the laser light according to the positioning error.

The laser processing device described in Patent Document 1 detects the scale of a glass scale formed on the galvano scanner by using a camera that can observe the surface of the processing object through the galvano scanner. The position of the scale mark, and the correction value for correcting the driving amount of the galvanometer scanner is obtained from the position of the scale mark and the detection result. [Prior Art Literature] [Patent Document]

Patent Document 1: Japanese Patent Laid-Open No. 2008-264789

[Problem to be Solved by the Invention]

However, in the technology of the above-mentioned Patent Document 1, since the galvanometer scanner is not linked with the camera, correction can only be performed within the range where the image of the processing object can be captured by the movement of the galvanometer scanner. , the problem that it cannot be corrected for the processing object area on the processing platform with a wider range than the galvanometer scanning area.

The present invention was developed in view of the above problems, and its object is to obtain a laser processing device capable of processing a processing target area on a processing platform with a wider range than the galvanometer scanning area with good accuracy. [means used to solve a problem]

In order to solve the above-mentioned problems and achieve the purpose, the laser processing device of the present invention is equipped with: a processing platform on which the object to be processed is placed; a galvano mirror (galvano mirror) that scans the object by irradiating laser light; The current meter scanner is driven by the galvano mirror. The laser processing device of the present invention is equipped with a measuring device that measures four or more fiducial marks when a reference plate with four or more fiducial marks arranged in a rectangular area is placed on a processing platform, and the processing object When the object is placed on the processing platform, the position of the alignment mark (alignment mark) provided on the processing surface of the object to be processed is measured. The laser processing device of the present invention is equipped with a control device. The control device calculates the positioning error of the processing platform and the correction coefficient for correcting the positioning error based on the measurement positions of more than four reference marks, and uses the correction coefficient to correct the alignment mark. Measure the position, and calculate the driving correction amount of the galvanometer scanner used to correct the positioning error based on the measured position of the corrected alignment mark, and control the object to be processed while driving the galvanometer scanner using the driving correction amount Laser processing. In the laser processing device of the present invention, when the correction coefficient is to be calculated, the process of making the measuring device interlock with the processing platform to measure more than four reference marks is repeatedly performed, and the control device is set to cover the entire area of the processing platform. to calculate the correction factor. [Efficacy of Invention]

The laser processing device of the present invention can achieve the effect of processing the processing target area on the processing platform with a wider range than the scanning area of the galvanometer with good accuracy.

The laser processing device, laser processing method, and error adjustment method of the embodiment of the present invention will be described in detail below based on the drawings. In addition, the present invention is not limited to this implementation form.

implementation type Fig. 1 is a diagram showing the configuration of a laser processing device of an embodiment. The laser processing device 100 is a device that corrects the positioning error of the processing platforms 2A, 2B on which the processing workpieces 3A, 3B belonging to the processing object are placed, and performs laser drilling processing on the processing workpieces 3A, 3B. The position correction of the processing platforms 2A, 2B performed by the laser processing device 100 is effective in making the galvanometer scanners 5A, 5B and the processing platforms 2A, 2B linked to perform processing.

In the laser processing device 100 , the reference plate used for measuring the positioning error is placed on the processing platforms 2A and 2B to measure the position of the reference mark arranged on the reference plate. The reference plate is a plate for measuring the position of the reference mark in a state placed on the processing platforms 2A and 2B. The laser processing device 100 calculates the positioning error of the processing platforms 2A and 2B based on the difference between the actual position of the reference mark and the measured 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 when the fiducial plate is placed on the processing platforms 2A, 2B.

The laser processing apparatus 100 repeats the process of measuring the reference marks by interlocking the cameras 7A and 7B with the processing platforms 2A and 2B, and calculates the correction coefficient so as to cover the entire area of the processing platforms 2A and 2B. The correction coefficient is used when correcting the positions of the processing platforms 2A and 2B. The laser processing apparatus 100 corrects the positions of the processing platforms 2A and 2B by correcting the positions of the alignment marks of the processing workpieces 3A and 3B arranged on the processing platforms 2A and 2B with correction coefficients. The alignment marks are marks for measuring the positions of the workpieces 3A, 3B placed on the processing platforms 2A, 2B, and are used when the positions of the workpieces 3A, 3B are to be corrected. Details about the alignment marks will be described later.

The laser processing apparatus 100 includes: a processing mechanism 20 for performing laser processing on processing workpieces 3A and 3B which are workpieces; and a control device 10 for controlling the processing mechanism 20 . The control device 10 calculates a correction coefficient using the least square approximation or the like for each measurement area where the reference mark is arranged. The control device 10 creates a calibration table showing the correspondence between the correction coefficient and the measurement area. The calibration table is a table used to correct the positioning errors of the processing platforms 2A and 2B. When controlling laser processing, the control device 10 extracts correction coefficients for each measurement area according to the calibration table, and applies the extracted correction coefficients to each measurement area to correct the positions where the laser beams 1A and 1B are to be irradiated.

The processing mechanism 20 separates the laser light (laser beam) output from the laser oscillator (not shown) into laser light 1A, 1B on the optical path, and processes the workpieces 3A, 1B on the processing platforms 2A, 2B. 3B is laser processed at the same time.

The processing mechanism 20 is equipped with: the 1st processing part which irradiates the laser beam 1A to the processing workpiece 3A; and the 2nd processing part which irradiates the laser beam 1B to the processing workpiece 3B. The first processing department has: galvanometer scanner 5A, galvanometer mirror 4A, camera 7A, fθ lens 6A, and processing platform 2A; the second processing department has: galvanometer scanner 5B, galvanometer mirror 4B, Camera 7B, fθ lens 6B, and processing platform 2B.

Moreover, the processing mechanism 20 is equipped with the driving platform 21 which drives the processing platforms 2A, 2B. The processing platforms 2A and 2B are XY processing platforms that can move in the XY plane of the horizontal plane. The processing platforms 2A, 2B move the workpieces 3A, 3B in the XY plane by moving in the X-axis direction and the Y-axis direction respectively, thereby adjusting the position where the laser light 1A, 1B irradiates the workpieces 3A, 3B .

The processing platform 2A fixes the processing workpiece 3A on the processing platform 2A by adsorbing the processing workpiece 3A, and the processing platform 2B fixes the processing workpiece 3B on the processing platform 2B by adsorbing the processing workpiece 3B. In this way, the machining mechanism 20 is configured such that the two machining platforms 2A, 2B are mounted on the driving platform 21, and the two machining workpieces 3A, 3B can be machined simultaneously.

Although the processing platforms 2A and 2B are both mounted on the drive platform 21 , the positioning error of the processing platform 2A is different from the positioning error of the processing platform 2B. Therefore, the control device 10 calculates the correction coefficient for the machining platform 2A and the correction coefficient for the machining platform 2B, respectively.

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

The galvanometer scanner 5A positions the irradiation position of the laser beam 1A at a machining target position on the machining workpiece 3A at high speed. The galvanometer scanner 5A includes: a galvano mirror 4A; a servo motor (not shown) that drives the galvano mirror 4A; and a drive control device (not shown) that controls the drive of the servo motor. In the galvanometer scanner 5A, the drive control device drives the galvano mirror 4A, and the galvano mirror 4A scans the workpiece 3A with the laser light 1A from the laser oscillator.

In the galvanometer scanner 5A, for example, the galvano mirror 4A is rotated within a range of a specific oscillation angle by a drive control device. The galvanometer scanner 5A receives an instruction from the control device 10 to move the irradiation position of the laser beam 1A so that the laser beam 1A is irradiated to the processing position of the target within the scanning area. Thus, in the galvanometer scanner 5A, the drive control device drives the galvano mirror 4A so that the laser light 1A is irradiated to a specific position in each scanning area within the processing surface of the workpiece 3A. The scanning area is an area scanned by the galvano mirror 4A. The scanning area corresponds to the drivable area of the galvanometer scanner 5A. The galvanometer scanner 5A repeats the operation of moving the irradiation position of the laser beam 1A to the next target position and then stopping after the irradiation of the laser beam 1A.

The first processing department 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 workpiece 3A is moved in the X-axis direction by rotating the galvano mirror 4A of the one galvanometer scanner 5A. In addition, in the first processing section, the irradiation position of the laser beam 1A on the workpiece 3A is moved in the Y-axis direction by rotating the galvano mirror 4A of the other galvanometer scanner 5A. The laser light 1A reflected by one galvanometer mirror 4A is transmitted to the other galvanometer mirror 4A, and is reflected by the other galvanometer mirror 4A. The laser light 1A reflected by the other galvanometer mirror 4A is irradiated to the workpiece 3A.

The fθ lens 6A condenses the laser light 1A on the workpiece 3A placed on the processing platform 2A. The camera 7A belonging to the measuring device observes the surface of the processing platform 2A and measures the positions of various marks. The camera 7A detects the position (coordinates) of the reference mark on the reference plate arranged on the processing table 2A when calculating the correction coefficient. The camera 7A detects the position (coordinate) of the alignment mark arranged on the processing workpiece 3A when the processing workpiece 3A is placed on the processing table 2A.

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

The camera 7A transmits the position of the fiducial mark which is the detection result of the fiducial mark and the position of the alignment mark which is the detection result of the alignment mark to the control device 10 .

In the laser processing device 100 , the laser light 1A from the laser oscillator is irradiated into the scanning area of the workpiece 3A through the galvanometer mirror 4A and the fθ lens 6A installed for each axis.

Since the area of the workpiece 3A is larger than the area of the scanning area, the laser processing device 100 moves the processing platform 2A from the scanning area to the next scanning area, and uses the galvanometer scanner 5A to move the scanning area within the scanning area. The irradiation position of the laser beam 1A moves. That is, the laser processing apparatus 100 moves the irradiation position of the laser beam 1A between scanning areas by the processing platform 2A, and moves the irradiation position of the laser beam 1A within the scanning area by the galvanometer scanner 5A. The laser processing apparatus 100 performs laser processing on the entire processing area of the workpiece 3A by irradiating the laser light 1A on each scanning area. That is, the laser processing apparatus 100 is configured to process all regions of the workpiece 3A by repeating the processing of moving the processing table 2A to each scanning area and the processing of irradiating the laser beam 1A on each scanning area.

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

Here, the configuration of the control device 10 will be described. Fig. 2 is a diagram showing the configuration of the control device included in the laser processing device of 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 transmitted from the camera 7A of the processing mechanism 20 and inputs it to the control unit 15 . Hereinafter, the position of the fiducial mark transmitted from the camera 7A is referred to as a measurement position. The input unit 11 receives the position of the alignment mark transmitted from the camera 7A of the processing mechanism 20 and inputs it to the correction amount calculation unit 14 .

The correction coefficient calculation unit 12 reads from the memory unit 13 information indicating the correspondence relationship between the actual position of the reference mark arranged in each measurement area of the reference plate and the measurement area. In addition, the correction coefficient calculation unit 12 reads information indicating the correspondence relationship 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 platform 2A. The actual position of the reference mark is the design value. Hereinafter, the actual position of the fiducial mark is called the actual position, and the information showing the correspondence between the actual position and the measurement area is called the actual position information. In addition, the information showing the correspondence between the measurement position and the measurement area is referred to as measurement position information.

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

The memory unit 13 stores actual location information. In addition, the storage unit 13 stores the measurement position information transmitted from the control unit 15 . In addition, the storage unit 13 stores the correction coefficient information transmitted from the correction coefficient calculation unit 12 .

The correction amount calculation unit 14 reads correction coefficient information from the storage unit 13 . The correction amount calculation unit 14 corrects the position (coordinates) of the alignment mark using the correction coefficient information. Specifically, the correction amount calculation unit 14 specifies the measurement area corresponding to the position of the alignment mark, and extracts the 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 by the correction coefficient is the correct position of the alignment mark after taking into account the position error of the processing platform 2A and the positional deviation of the workpiece 3A. Therefore, the correction amount calculation unit 14 calculates the drive correction amount (hereinafter referred to as the current correction amount) for correcting the drive amount of the galvanometer scanner 5A and the position of the processing table 2A based on the corrected position of the alignment mark. ) The formula of the corresponding relationship. This formula is a formula for obtaining the current correction amount corresponding to the coordinates on the processing platform 2A by substituting the X coordinate and the Y coordinate on the processing platform 2A. The coordinates (X coordinate and Y coordinate) of the processing platform 2A are the center coordinates of the scanning area performed by the galvanometer scanner 5A.

The correction amount calculation unit 14 calculates the current correction amount corresponding to the position of the machining table 2A specified by the machining formula. The correction amount calculation unit 14 sends the calculated current correction amount to the control unit 15 .

The control unit 15 controls the machining mechanism 20 . The control unit 15 transmits a driving instruction to the galvanometer scanner 5A, the processing platform 2A, and the like. The control unit 15 moves the processing table 2A when the correction coefficient information is calculated, thereby moving the imaging position of the camera 7A to the position of the reference mark arranged in the measurement area. The imaging position of the camera 7A is the center position of the scanning area. The control unit 15 generates measurement position information after establishing a correspondence relationship between the measurement area corresponding to the imaging position of the camera 7A and the actual position transmitted from the input unit 11 . The actual position transmitted from the input unit 11 is the actual position measured in the measurement area corresponding to the imaging position of the camera 7A. The control unit 15 transmits the measured position information to the memory unit 13 .

In addition, the control unit 15 corrects the drive amount of the galvanometer scanner 5A using the current correction amount for each stage position belonging to the position of the processing stage 2A when the galvanometer scanner 5A is to be driven. The control unit 15 transmits the driving instruction after the driving amount of the galvanometer scanner 5A is corrected to the processing mechanism 20 . Accordingly, the oscillation angle of the galvanometer mirror 4A is corrected, and thus the irradiation position of the laser beam 1A is corrected.

In this way, the control device 10 of the embodiment calculates the current correction amount for correcting the positioning error of the machining platform 2A using the measurement position of the reference mark, and drives the galvanometer scanner 5A using the current correction amount.

Next, the calculation procedure of the correction coefficient performed by the laser processing apparatus 100 will be described. Fig. 3 is a flow chart showing the calculation processing procedure of the correction coefficient performed by the laser processing device of the embodiment. Fig. 4 is a diagram for explaining the measurement area of the reference plate used in the laser processing device of the embodiment. Fig. 5 is a diagram for explaining reference marks measured by the laser processing device of 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 from the measured position. This is because the positional deviation of the reference mark M cannot be measured when the position correction is enabled. Therefore, the control device 10 of the laser processing device 100 sets the position correction of the processing platform 2A to be invalid when the position correction of the processing platform 2A is already valid (step S1 ). That is, in the laser processing apparatus 100, when the setting of the driving amount of the corrected galvanometer scanner 5A is valid, the setting of the corrected driving amount of the galvanometer scanner 5A is disabled.

The processing table 2A is for mounting the reference plate 8 used as a reference for preparing a calibration table. The reference plate 8 has a plurality of reference marks M printed on the reference plate 8 at equal intervals. The reference marks M are arranged in a grid pattern in an area that can cover the entire surface of the processing platform 2A. In addition, the reference mark M may be arranged on the upper surface of the reference plate 8 by methods other than printing. In addition, the reference mark M may be arranged in a shape other than the grid shape. The reference plate 8 is a quartz glass plate or the like in which the arrangement accuracy of the reference mark M is good. In the laser processing apparatus 100, the reference plate 8 is set as the main scale (master scale) of the processing platform 2A, that is, the reference scale.

As shown in FIG. 4 , in the reference plate 8 , a plurality of measurement regions including a measurement region 30n and a measurement region 30 (n+1) are provided on the entire surface. Here n is a natural number. The measurement regions set on the reference plate 8 have the same shape and size, so the measurement region 30n will be described below. The measurement area 30n is a rectangular area, and a reference mark M is arranged at each of the four vertices. In Fig. 5, four reference marks M in the measurement region 30n are illustrated by reference marks P1 to P4. Among the measurement areas on the reference plate 8 , the more areas there are, that is, the narrower each measurement area is, the more accurate positional offset correction can be performed.

The reference plate 8 is formed using, for example, a plate-shaped member with a length of 800 mm in the X-axis direction and 600 mm in the Y-axis direction. In addition, an example of the scanning area corresponding to the operable area of the galvanometer scanner 5A is 30 mm×30 mm.

In the reference plate 8, there are two reference marks M (one side belonging to the line segment area between the two reference marks M) in common by the measurement areas adjacent to each other. For example, the measurement region 30(n+1) adjacent to the measurement region 30n and the measurement region 30n share two reference marks M. Specifically, the fiducial marks P3 and P4 are fiducial marks arranged on the right side of the measurement area 30n, and are fiducial 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. In this way, the adjacent measurement areas share one side, whereby the measurement areas are set in a grid pattern on the reference plate 8 .

The laser processing device 100 repeats until m=1 to 4: the process of moving the imaging position of the camera 7A to the reference mark Pm of the measurement area 30n, the process of measuring the position of the reference mark Pm, and saving the measured Processing of data. Specifically, the control unit 15 moves the processing table 2A to a table position on the reference mark P1 of the measurement area 30n where the imaging position of the camera 7A becomes. The imaging position of the camera 7A is the position on the reference plate 8 captured by the camera 7A. That is, the laser processing apparatus 100 moves the imaging position of the camera 7A to the reference point of the measurement area 30n by moving 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. Mark P1 on (step S2).

The laser processing apparatus 100 measures the position of the fiducial mark P1 by the camera 7A (step S3). In FIG. 5 , the measurement position of the measurement result belonging to the reference mark P1 is illustrated as the measurement position Q1 . The laser processing device 100 transmits the measurement position Q1 to the control device 10 . Thereby, the laser processing device 100 saves the measurement information (step S4). Specifically, the laser processing device 100 establishes a correspondence relationship between the measurement area 30 n and the measurement position Q1 of the reference mark P1 , and stores them in the memory unit 13 .

The laser processing apparatus 100 determines whether the positions from the reference mark P1 to the reference mark P4 have been measured (step S5). When the position has not yet been measured to the reference mark P4 (step S5: No), the laser processing apparatus 100 repeats the processing of steps S2 to S5. That is, the laser processing apparatus 100 repeats the process of step S2 to step S5 until the position of the reference mark P4 is measured (until m=4).

That is, the laser processing device 100 moves the processing platform 2A to the position of the fiducial mark P2 (step S2), measures the position of the fiducial mark P2 (step S3), and compares the measurement area 30n with the measurement result belonging to the fiducial mark P2 The corresponding relationship between the measurement positions Q2 is established and stored by the memory unit 13 (step S4).

Similarly, the laser processing device 100 moves the processing platform 2A to the position of the fiducial mark P3 (step S2), measures the position of the fiducial mark P3 (step S3), and compares the measurement area 30n with the measurement result belonging to the fiducial mark P3 The corresponding relationship between the measurement positions Q3 is established and saved by the memory unit 13 (step S4).

Similarly, the laser processing device 100 moves the processing platform 2A to the position of the fiducial mark P4 (step S2), measures the position of the fiducial mark P4 (step S3), and compares the measurement area 30n with the measurement result belonging to the fiducial mark P4 The corresponding relationship between the measurement positions Q4 is established and saved by the memory unit 13 (step S4). In this way, the processing platform 2A moves the fiducial marks sequentially to the measurement position to be performed by the camera 7A by moving. The information corresponding to the measurement area 30n and the measurement locations Q1 to Q4 is the measurement location information.

When the measurement position reaches the reference mark P4 (step S5: Yes), the correction coefficient calculation unit 12 reads the actual position information and the measurement position information from the memory unit 13, and according to the actual position deviation and the measurement position information, Calculate the difference between the actual position and the measured position. 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 it in the memory 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 belonging to the measurement positions. Specifically, the correction coefficient calculation unit 12 calculates a correction coefficient by applying the least square approximation to the differences between the four actual positions and the four measurement positions Q1 to Q4 . In addition, the correction coefficient calculation unit 12 may calculate the correction coefficient for the platform position within the measurement area 30n by performing parallelogram correction or trapezoidal correction in addition to the correction coefficient.

In addition, the camera 7A is not limited to measuring the positions of the fiducial marks P1 to P4 at four places within the measurement area 30n, and may measure the positions of the fiducial marks at five or more places. That is, four or more (at least four) reference marks may be arranged in the measurement area 30n. At this time, the camera 7A measures four or more reference marks in the measurement area 30n, and the correction coefficient calculation unit 12 calculates a correction coefficient using the measurement position information of the four or more reference marks. Here, the reason for measuring the positions of four or more reference marks is that 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.

The control unit 15 determines whether correction coefficients have been calculated for all the measurement areas (step S7). When there is a measurement area for which no correction coefficient has been calculated (step S7: No), the laser processing apparatus 100 executes the processes of step S2 to step S6 for the measurement area for which no correction coefficient has been calculated according to an instruction from the control unit 15 . The laser processing apparatus 100 executes the process of step S2 to step S6 for each measurement area until a correction coefficient is 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 calculation process of the correction coefficient.

The correction coefficient calculation unit 12 uses the correction coefficients for all the calculated measurement areas to create a calibration table showing the correspondence between the correction coefficients and the measurement areas. The correction coefficient calculation unit 12 can perform calibration with high accuracy for the platform position between the reference marks in the measurement area 30n when calculating the correction coefficient in each measurement area by parallelogram correction or trapezoidal correction. surface.

Fig. 6 is a diagram for explaining the relationship between the actual position and the measured position of the reference mark obtained by the laser processing device of the embodiment. In FIG. 6, the correspondence relationship between the actual position AP of the reference mark M arranged on the reference plate 8 and the measurement position MQ is shown. In addition, in FIG. 6 , the difference between the actual position AP and the measured position MQ is magnified 1000 times and illustrated. The actual positions AP are arranged on the entire surface of the reference plate 8, and the laser processing apparatus 100 measures the measurement positions MQ for each actual position AP. The measured position MQ superimposed on the actual position AP is the measured position MQ corresponding to the actual position AP. In addition, when the reference plate 8 is fixed on the processing platform 2A with the reference point BP located at the upper left position in the entire area of the reference plate 8 as a reference, the farther the position is from the reference point BP, the difference between the reference position and the actual position ( error) becomes larger.

The laser processing apparatus 100 calculates the current correction amount after calculating the correction coefficient information, and executes the laser processing of the workpiece 3A using the current correction amount. Here, the calculation processing procedure of the current correction amount performed by the laser processing apparatus 100 will be described.

Fig. 7 is a flow chart showing the calculation processing procedure of the current correction amount performed by the laser processing device of the embodiment. The laser processing apparatus 100 starts processing the workpiece 3A in a state where the reference plate 8 is removed from the processing platform 2A and the workpiece 3A is placed on the processing platform 2A.

The laser processing apparatus 100 sets the position correction of the processing platform 2A to be valid (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 workpiece 3A (step S12). That is, the laser processing apparatus 100 moves the imaging position of the camera 7A to the stage position corresponding to the alignment mark by moving the processing stage 2A. The camera 7A measures the position of the alignment mark (step S13).

Fig. 8 is a diagram for explaining alignment marks used in the laser processing device of the embodiment. Fig. 8 shows the workpiece 3A when the workpiece 3A placed on the processing platform 2A is viewed from the upper side. Alignment marks 9 are respectively arranged at the positions of the four vertices of the workpiece 3A or near the positions of the vertices.

The camera 7A transmits the position of the alignment mark 9 , which is a measurement result of the alignment mark 9 , to the control device 10 . The correction amount calculation unit 14 of the control device 10 calculates the alignment correction amount based on the position of the alignment mark 9 and the correction coefficient information, and applies it to the correction of 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 or not the alignment correction amounts have 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 executes the step S12 to the processing of step S14. The laser processing apparatus 100 executes the processing of 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 calculates the laser processing time of each platform position based on the calculated alignment correction amounts. The current correction amount (step S16).

In this way, the control device 10 calculates the positioning error of the machining platform 2A in each measurement area based on the measurement position MQ of the reference mark, calculates a correction coefficient for correcting the positioning error based on the positioning error, and corrects the alignment mark using the correction coefficient. 9, and calculate the current correction amount according to the corrected position of the alignment mark 9.

The correction amount calculation unit 14 calculates the current correction amount for each stage position, and the control unit 15 executes laser processing while correcting the drive amount of the galvanometer scanner 5A using the current correction amount for each stage position. Thereby, since the oscillation angle of the galvanometer mirror 4A is corrected for each stage position, the irradiation position of the laser light 1A is corrected for each stage position. The correction of the irradiation position of the laser light 1A corresponds to the correction of the positioning error of the processing platform 2A, so the laser processing device 100 can perform processing in the state where the positioning error of the processing platform 2A is corrected according to each platform position. Laser processing of workpiece 3A.

According to this embodiment, the positioning accuracy of the processing platform 2A is improved from 13.33 μm to 6.46 μm. That is, the positioning error of the laser processing apparatus 100 using the reference plate 8 and correcting the positioning error of the processing table 2A is 6.46 μm compared to the positioning error of 13.33 μm when the positioning error of the processing table 2A is not corrected.

In addition, according to this embodiment, the positioning accuracy of the processing platform 2B is improved from 11.65 μm to 7.62 μm. That is, compared to 11.65 μm when the positioning error of the processing platform 2B is not corrected, the positioning error of the laser processing apparatus 100 using the reference plate 8 and correcting the positioning error of the processing platform 2B is 7.62 μm.

In the processing platform 2A, there is verticality or straightness depending on the processing accuracy of the processing platform 2A itself. Therefore, when the machining table 2A is moved, not only a one-dimensional shift for each moving axis but also a two-dimensional shift (rotational shift) occurs. In this embodiment, 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, the correction coefficient is calculated by the least square approximation, so the processing platform can be corrected Two-dimensional offset of the movement of 2A.

In addition, in this embodiment, since the processing table 2A is moved without driving the galvanometer scanner 5A, a calibration table for correcting the positioning error of the processing table 2A is created. Therefore, a correction coefficient capable of bringing the positioning error of the processing table 2A in the actual position AP of the reference mark M close to zero can be obtained by creating the table once. Therefore, the preparation time of the calibration table can be reduced, and the accuracy of correction of positioning errors can be improved, so that high-precision laser processing can be realized efficiently.

In addition, by performing parallelogram correction or trapezoidal correction, correction coefficients can also be obtained for the stage position in the measurement area 30n, so the positioning error of the processing stage 2A can be corrected between the reference marks M with high accuracy.

Here, the hardware configuration of the control device 10 will be described. Fig. 9 is a diagram showing an example of the hardware configuration of the control device of the embodiment. The control device 10 can be realized by a processor 301 , a memory 302 , and an interface circuit 303 shown in FIG. 9 . The processor 301, the memory 302, and the interface circuit 303 can transmit and receive data with each other through a bus. The example of processor 301 is CPU (Central Processing Unit, also known as central processing device, processing device, calculation device, microprocessor (micro processor), microcomputer (micro computer), processor, DSP (Digital Signal Processor, digital processor) )) or system LSI (Large Scale Integration, large integrated circuit). An example of the memory 302 is RAM (Random Access Memory, random access memory) or ROM (Read Only Memory, read-only memory).

The control device 10 is realized by the processor 301 reading and executing the program stored in the memory 302 for executing the actions of the control device 10 . In addition, this program can also be called a program or a method for causing a computer to execute 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 can also be a computer program product that can be read by a computer and is a non-transitory recording medium that can be executed by a computer and includes a plurality of commands for data processing. The program executed by the processor 301 is to make the computer execute a plurality of commands for data processing.

In addition, the control device 10 can also be realized by dedicated hardware. In addition, the functions of the control device 10 may be partially implemented by dedicated hardware and partially implemented by software or firmware.

In addition, in this embodiment, although it has been described that the processing mechanism 20 separates the laser light into two laser beams 1A, 1B, and the two processing workpieces 3A, 3B are simultaneously processed by the two processing platforms 2A, 2B. In the case of laser processing, the configuration of the processing mechanism 20 is not limited to this configuration. The machining mechanism 20 may also be configured to process a plurality of workpieces with one machining platform, or may be configured to process a plurality of workpieces by installing a plurality of machining platforms on a plurality of drive systems.

In this way, according to the embodiment, the positioning error of the processing platform 2A is calculated based on the measurement positions of more than four fiducial marks, and the process of making the camera 7A and the processing platform 2A linked to measure the fiducial marks is repeated to cover the processing platform 2A. The positioning error can be calculated in the manner of the entire area of the galvanometer scanner, so the range that the galvanometer scanner 5A can correspond to (the range where the image of the processing object can be captured by the movement of the galvanometer scanner 5A), that is, can be compared The galvanometer scans the larger processing object area, and calculates the current correction amount for the positioning error. Therefore, it is possible to precisely process a processing target area larger than the range that the galvanometer scanner 5A can handle. In addition, since the positioning error of the machining platform 2A is calculated based on the measurement positions MQ of the four or more reference marks M, and the current correction amount is calculated according to the positioning error, the accuracy corresponding to the positioning error of the machining platform 2A can be calculated in a short time. High current correction amount. Therefore, high-precision machining can be realized in a short time.

The configuration shown in the above embodiments is an example showing the content of the present invention, and may be combined with other known techniques, and a part of the configuration may be omitted or changed without departing from the gist of the present invention.

1A, 1B: laser light 2A, 2B: processing platform 3A, 3B: machining workpiece 4A, 4B: Galvano mirror 5A, 5B: Galvanometer Scanner 6A, 6B: fθ lens 7A, 7B: camera 8: Reference plate 9: Alignment marks 10: Control device 11: Input part 12: Correction coefficient calculation part 13: Memory Department 14: Correction amount calculation part 15: Control Department 20: Processing mechanism 21: Drive platform 30n, 30(n+1): measurement area 100:Laser processing device 301: Processor 302: memory 303: interface circuit AP: actual location BP: benchmark point M, P1 to P4: Fiducial marks MQ, Q1 to Q4: Measuring positions

Fig. 1 is a diagram showing the configuration of a laser processing device of an embodiment. Fig. 2 is a diagram showing the configuration of the control device included in the laser processing device of the embodiment. Fig. 3 is a flow chart showing the calculation processing procedure of the correction coefficient performed by the laser processing device of the embodiment. Fig. 4 is a diagram for explaining the measurement area of the reference plate used in the laser processing device of the embodiment. Fig. 5 is a diagram for explaining reference marks measured by the laser processing device of the embodiment. Fig. 6 is a diagram for explaining the relationship between the actual position and the measured position of the reference mark obtained by the laser processing device of the embodiment. FIG. 7 is a flow chart showing the calculation processing procedure of the current correction amount performed by the laser processing device of the embodiment. Fig. 8 is a diagram for explaining alignment marks used in the laser processing device of the embodiment. Fig. 9 is a diagram showing an example of the hardware configuration of the control device of the embodiment.

10: Control device

11: Input part

12: Correction coefficient calculation part

13: Memory Department

14: Correction amount calculation part

15: Control Department

20: Processing mechanism

Claims (7)

A laser processing device is provided with: a processing platform, on which an object to be processed is placed; a galvanometer, which scans the object by irradiating laser light on the object to be processed; a galvanometer scanner, which drives the above-mentioned galvano mirror; A device for measuring the above-mentioned four or more fiducial marks when a reference plate with four or more fiducial marks arranged in a rectangular area is placed on the aforementioned processing platform, and measuring when the aforementioned processing object is placed on the aforementioned processing platform The position of the alignment mark provided on the processing surface of the aforementioned object to be processed; and the control device, which calculates the positioning error of the aforementioned processing platform and the correction coefficient for correcting the aforementioned positioning error based on the measurement positions of the aforementioned four or more reference marks, and The measurement position of the alignment mark is corrected using the correction coefficient, and the driving correction amount of the galvanometer scanner for correcting the positioning error is calculated based on the corrected measurement position of the alignment mark, and while using the aforementioned Drive the correction amount to drive the galvanometer scanner to control the laser processing of the object to be processed; on the reference plate, a plurality of the reference marks are arranged in a grid at equal intervals in an area that can cover the entire surface of the processing platform shape; the aforementioned rectangular area is provided with plural numbers on the entire surface of the aforementioned reference plate; when the aforementioned correction coefficient is to be calculated, the process of making the aforementioned measuring device and the aforementioned processing platform linked to measure the aforementioned four or more benchmark marks is repeated, and by the aforementioned The control device calculates the correction coefficient so as to cover the entire area of the processing platform. The laser processing device as described in claim 1 of the patent claims, wherein the control device calculates the driving correction amount by using the positioning error of the rectangular area corresponding to the position of the alignment mark among the positioning errors. The laser processing device as described in item 1 or item 2 of the scope of patent application, wherein the aforementioned control device applies the least square approximation to the difference between the actual position of the aforementioned reference mark and the aforementioned measured position, and calculates the area of the aforementioned rectangular area. The aforementioned positioning error. The laser processing device as described in claim 3 of the patent application, wherein the aforementioned control device calculates the positioning error in the aforementioned rectangular area through parallelogram correction or trapezoidal correction. In the laser processing device described in claim 1 of the patent application, wherein, the aforementioned rectangular area is adjacent to an adjacent rectangular area and shares the adjacent sides. A laser processing method comprising the following steps: a placing step, for a laser processing device, a step of placing a reference plate with four or more reference marks arranged in a rectangular area on a processing platform, the laser processing The device is equipped with: the aforementioned processing platform, which places the object to be processed; the galvanometer, which scans the object by irradiating laser light on the object to be processed; the galvanometer scanner, which drives the aforementioned galvanometer; the measuring device, which Observe the surface of the aforementioned processing platform; and the control device is to control the laser processing of the aforementioned processing object; the first measurement step is to measure the aforementioned four or more reference marks by the aforementioned measuring device; the first calculation step is to use the aforementioned control device The device calculates the positioning error of the processing platform and the correction coefficient to correct the positioning error according to the measurement positions of the above-mentioned four or more above-mentioned reference marks; the second measurement step is when the object to be processed is placed on the processing platform In this state, the position of the alignment mark set on the processing surface of the object to be processed is measured by the measuring device; The correcting step is to correct the measurement position of the aforementioned alignment mark by the aforementioned control device using the aforementioned correction coefficient; The driving correction amount of the aforementioned galvanometer scanner for the positioning error; and the control step is that the aforementioned control device uses the aforementioned driving correction amount to drive the aforementioned galvanometer scanner while controlling the laser processing of the aforementioned processing object; For the aforementioned reference plate, a plurality of the aforementioned reference marks are arranged in a grid at equal intervals in an area that can cover the entire surface of the aforementioned processing platform; the aforementioned rectangular area is provided with plural numbers on the entire surface of the aforementioned reference plate; when the aforementioned correction is to be calculated For the coefficient, the process of measuring the reference mark by interlocking the measuring device with the processing platform is repeated, and the correction coefficient is calculated by the control device so as to cover the entire area of the processing platform. An error adjustment method comprising the following steps: a placing step, for a laser processing device, a step of placing a reference plate with four or more reference marks arranged in a rectangular area on a processing platform, the laser processing device The system includes: the aforementioned processing platform, which places the object to be processed; the galvanometer, which scans the object by irradiating laser light; the galvanometer scanner, which drives the aforementioned galvanometer; the measuring device, which observes The surface of the aforementioned processing platform; and the control device is to control the laser processing of the aforementioned processing object; the first measurement step is to measure the aforementioned four or more reference marks by the aforementioned measuring device; the first calculation step is to use the aforementioned control device Calculate the positioning error of the aforementioned processing platform and the correction coefficient to correct the aforementioned positioning error according to the measurement positions of the aforementioned reference marks at more than four locations; The second measurement step is to measure the position of the alignment mark provided on the processing surface of the aforementioned object to be processed by the aforementioned measuring device under the condition that the aforementioned object to be processed is placed on the aforementioned processing platform; the correction step is to The aforementioned control device uses the aforementioned correction coefficient to correct the measured position of the aforementioned alignment mark; the second calculation step is to calculate the aforementioned detection position for correcting the aforementioned positioning error by the aforementioned control device based on the corrected measured position of the aforementioned alignment mark. The driving correction amount of the galvanometer scanner; and the control step, the aforementioned control device uses the aforementioned driving correction amount to drive the aforementioned galvanometer scanner while controlling the laser processing of the aforementioned object to be processed; on the aforementioned reference plate, a plurality of The above-mentioned reference marks are arranged in a grid at equal intervals in an area that can cover the entire surface of the aforementioned processing platform; the aforementioned rectangular area is provided with multiples on the entire surface of the aforementioned reference plate; when the aforementioned correction coefficient is to be calculated, it is repeated. The process of measuring the reference mark by linking the measuring device with the processing platform, and calculating the correction coefficient by the control device covering the entire area of the processing platform; the control device is controlling the laser of the object to be processed During processing, the aforementioned positioning error is corrected with the aforementioned correction coefficient.

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