JP2022151978A - Laser processing device and method - Google Patents

Abstract

To provide a laser processing device capable of reducing discontinuous movement of a laser beam focal position in a Z-axis direction which crosses at a right angle, an XY axis direction where the laser beam is scanned, for securing quality of laser processing, and shortening a period for laser processing.SOLUTION: A laser processing device is configured so that, in a Z-axis direction, a difference between a first endmost position ME1 where a processing plane 8 of a processing target 7 is closest to an upstream side of processing laser beam P, and a second endmost position ME2 where the processing plane 8 of the processing target 7 is closest to a downstream of the processing laser beam P, is one to two times of a focal depth of the processing laser beam P, identifies a focal position when an upstream limit position of the focal depth matches the first endmost position ME1, as a first focal position F1, and identifies a focal position when a downstream limit position of the focal depth matches the second endmost position ME2, as a second focal position F2, then executes laser processing at a switching mode for switching the focal position to the first or second focal position F1, F2.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a laser processing apparatus in which the focal position of laser light moves discontinuously in the Z-axis direction perpendicular to the XY-axis direction in which the laser light is scanned.

Conventionally, various techniques have been proposed for the laser processing apparatus. For example, the laser processing apparatus described in Patent Document 1 below includes a laser beam emitting unit that emits a laser beam, a scanning unit that scans the laser beam, and an imaging unit that can obtain an image of the laser beam suitable for processing. An imaging plane variable means for varying the distance of the surface from the laser light emitting section, and a control section, wherein the control section controls the laser light emitting section and the scanning section so as to match the processing pattern. Based on the processing of irradiating the laser beam onto the object to be processed, and controlling the imaging plane variable means, the focal depth of the laser beam is controlled according to the height of the processed surface of the object to be processed. and an imaging plane adjustment process of adjusting the position of the imaging plane discontinuously at each predetermined interval, with a predetermined interval as an adjustment unit.

Japanese Patent Application Laid-Open No. 2019-63810

In the laser processing apparatus of Patent Document 1, according to the height of the processing surface of the object to be processed, the position of the imaging plane is discontinuous for each predetermined interval with a predetermined interval based on the depth of focus of the laser beam as an adjustment unit. Therefore, it is possible to shorten the processing time while performing laser processing with appropriate quality, but there is a demand for technological development to further reduce the processing time. .

Therefore, the present disclosure has been made in view of the above points, and reduces discontinuous movement of the focal position of the laser light in the Z-axis direction perpendicular to the XY-axis direction in which the laser light is scanned. To provide a laser processing apparatus that further shortens the time for laser processing while ensuring the quality of laser processing.

This specification includes a laser beam emitting unit that emits a laser beam for performing laser processing on a workpiece surface based on processing data, an XY-axis scanning unit that scans the laser beam in the XY-axis directions of an orthogonal coordinate system, and a laser beam. A variable focus optical system that moves the focal position of light in the Z-axis direction of the orthogonal coordinate system, a receiving unit that receives three-dimensional data of the work surface, and drive control of the XY axis scanning unit and variable focus optical system during laser processing. and a control unit for controlling the laser beam, based on the depth of focus of the laser beam, in the Z-axis direction, the upstream limit position indicating the limit position on the upstream side of the laser beam, and the limit position on the downstream side of the laser beam. a first extreme position indicating the position where the workpiece surface is most upstream of the laser beam in the Z-axis direction; If it is determined based on three-dimensional data that the difference from the second extreme position indicating the position on the downstream side is 1 to 2 times the depth of focus of the laser light, the depth of focus of the laser light Assuming a first state in which the upstream limit position coincides with the first extreme position, the focal position of the laser beam is set to the first focal position, and the downstream limit position of the focal depth of the laser beam is the second extreme position. Assuming a second state that coincides with the end position, the focal position of the laser light is set to the second focal position, and the focal position of the laser light is set to the first focal position or the second focal position based on the three-dimensional data Disclosed is a laser processing apparatus characterized by performing laser processing in switching modes.

According to the present disclosure, the laser processing apparatus reduces discontinuous movement of the focal position of the laser beam in the Z-axis direction perpendicular to the XY-axis direction in which the laser beam is scanned, thereby performing laser processing. To further shorten the laser processing time while ensuring the quality of

BRIEF DESCRIPTION OF THE DRAWINGS It is the figure by which the schematic structure of the laser processing apparatus of this embodiment was represented. It is a block diagram showing an electrical configuration of the same laser processing apparatus. FIG. 4 is a diagram for explaining an upstream limit position and a downstream limit position of the depth of focus of processing laser light; It is a figure for demonstrating the 1st extreme-end position and the 2nd extreme-end position of the processing surface of a workpiece. 4 is a flow chart showing each process executed by the laser processing apparatus; 4 is a flow chart showing each process executed by the laser processing apparatus; FIG. 10 is a diagram for explaining the setting contents of the setting process of the first timing; FIG. FIG. 10 is a diagram for explaining the setting contents of the setting process of the first timing; FIG. FIG. 11 is a diagram for explaining the setting contents of the setting process of the second timing; FIG. FIG. 11 is a diagram for explaining the setting contents of the setting process of the second timing; FIG. FIG. 10 is a diagram for explaining how the focal position of the processing laser beam is switched according to the setting contents of the setting process of the first timing; FIG. 10 is a diagram for explaining how the focal position of the processing laser beam is switched according to the setting contents of the setting process of the second timing;

Hereinafter, a laser processing apparatus of the present disclosure will be described based on specific embodiments with reference to the drawings. In FIGS. 1 and 2 used for the following explanation, a part of the basic configuration is omitted, and the dimensional ratios and the like of the drawn parts are not necessarily accurate. In the following description, the X-axis direction, Y-axis direction, and Z-axis direction of the orthogonal coordinate system are as shown in the drawings. The vertical direction is parallel to the Z-axis direction of the orthogonal coordinate system, as shown in the drawings.

[1. Schematic configuration of laser processing device]
First, based on FIG.1 and FIG.2, schematic structure of the laser processing apparatus 1 of this embodiment is demonstrated. A laser processing apparatus 1 of the present embodiment is composed of a print information creating section 2 and a laser processing section 3 . The print information creation unit 2 is composed of a personal computer or the like.

The laser processing unit 3 two-dimensionally scans the processing surface 8 of the processing object 7 with the processing laser beam P to perform marking (printing) processing. The laser processing unit 3 has a laser controller 6 . In the following description, marking (printing) processing may be described as laser processing.

The laser controller 6 is composed of a computer, and is connected to the print information creating section 2 so as to be able to communicate bidirectionally. The laser controller 6 drives and controls the laser processing unit 3 based on the print information, control parameters, various instruction information, and the like transmitted from the print information creation unit 2 .

A schematic configuration of the laser processing unit 3 will be described. The laser processing unit 3 includes a laser oscillation unit 12, a guide light unit 15, a dichroic mirror 101, an optical system 70, a galvanometer scanner 18, an fθ lens 19, and the like, and is covered with a substantially rectangular parallelepiped housing cover (not shown). It is

The laser oscillation unit 12 is composed of a laser oscillator 21 and the like. The laser oscillator 21 is composed of a CO2 laser, a YAG laser, a fiber laser, or the like, and emits processing laser light P. As shown in FIG. The diameter of the processing laser beam P is adjusted (eg, enlarged) by a beam expander (not shown).

The guide light section 15 is composed of a visible semiconductor laser 28 or the like. The visible semiconductor laser 28 emits guide light Q, which is visible coherent light, such as red laser light. The guide light Q is collimated by a lens group (not shown), and is scanned two-dimensionally to surround, for example, an image of a print pattern to be marked (printed) by the processing laser light P, and the image. A rectangular image, an image of a predetermined shape, or the like is drawn on the processing surface 8 of the processing object 7 in a trajectory (time afterimage). In other words, the guide light Q has no marking (printing) processing ability.

The wavelength of the guide light Q is different from the wavelength of the processing laser light P. As shown in FIG. In this embodiment, for example, the wavelength of the processing laser beam P is 1064 nm, and the wavelength of the guide beam Q is 650 nm.

The dichroic mirror 101 allows almost all of the incident processing laser beam P to pass therethrough. Further, in the dichroic mirror 101, the guide light Q is incident at an incident angle of 45 degrees at a substantially central position through which the processing laser light P is transmitted, and is reflected onto the optical path of the processing laser light P at a reflection angle of 45 degrees. . The reflectance of the dichroic mirror 101 has wavelength dependence. Specifically, the dichroic mirror 101 is surface-treated to have a multilayer structure of dielectric layers and metal layers, and has a high reflectance with respect to the wavelength of the guide light Q. is configured to transmit most (99%) of the

1 indicates the optical axis 10 of the processing laser beam P and the guide beam Q. In FIG. Also, the direction of the optical axis 10 indicates the path direction of the processing laser beam P and the guide beam Q. As shown in FIG.

The optical system 70 has a first lens 72 , a second lens 74 and a moving mechanism 76 . In the optical system 70 , the processing laser beam P and the guide beam Q that have passed through the dichroic mirror 101 enter and pass through the first lens 72 . At that time, the light diameters of the processing laser light P and the guide light Q are reduced by the first lens 72 . The processing laser beam P and the guide beam Q that have passed through the first lens 72 enter and pass through the second lens 74 . At that time, the processing laser beam P and the guide beam Q are collimated by the second lens 74 . The moving mechanism 76 includes an optical system motor 80 and a rack and pinion (not shown) that converts the rotational motion of the optical system motor 80 into linear motion. The lens 74 is moved in the path direction of the processing laser beam P and the guide beam Q. As shown in FIG.

The moving mechanism 76 may be configured to move the first lens 72 instead of the second lens 74, or the first lens 72 and the second lens 74 may be moved such that the distance between the first lens 72 and the second lens 74 is changed. A configuration in which both the lens 72 and the second lens 74 are moved may be used. Also, the moving mechanism 76 may be of a voice coil motor type.

The galvanometer scanner 18 two-dimensionally scans the processing laser beam P and the guide beam Q that have passed through the optical system 70 . In the galvano scanner 18, a galvano X-axis motor 31 and a galvano Y-axis motor 32 are mounted so that their respective motor shafts are perpendicular to each other, and scanning mirrors 18X and 18Y mounted on the tips of the respective motor shafts are arranged inside. facing each other. By rotating the scanning mirrors 18X and 18Y by controlling the rotation of the motors 31 and 32, the processing laser beam P and the guide beam Q are two-dimensionally scanned. The two-dimensional scanning directions are the X-axis direction and the Y-axis direction.

The f.theta. Accordingly, the machining laser beam P and the guide beam Q are two-dimensionally scanned in the X-axis direction and the Y-axis direction on the machining surface 8 of the workpiece 7 by controlling the rotation of the motors 31 and 32 .

The processing laser light P and the guide light Q have different wavelengths. Therefore, when the distance between the first lens 72 and the second lens 74 in the optical system 70 is constant, the position where the processing laser light P and the guide light Q converge (hereinafter referred to as "focus position F") is , differ in the vertical direction (Z-axis direction). Therefore, the focal position F of the processing laser beam P and the guide beam Q is moved in the vertical direction (Z-axis direction) by adjusting the distance between the first lens 72 and the second lens 74 in the optical system 70. , and is aligned with the machining surface 8 of the workpiece 7 .

Similarly, when the position of the processing surface 8 of the processing object 7 is different in the vertical direction (Z-axis direction), the focal position F of the processing laser beam P and the guide beam Q is the first lens in the optical system 70. By adjusting the distance between 72 and second lens 74 , it moves in the vertical direction (Z-axis direction) and is aligned with the processing surface 8 of the processing object 7 .

Next, the circuit configurations of the print information generating section 2 and the laser processing section 3 that constitute the laser processing apparatus 1 will be described with reference to FIG. First, the circuit configuration of the laser processing unit 3 will be described.

As shown in FIG. 2, the laser processing unit 3 includes a laser controller 6, a galvano controller 35, a galvano driver 36, a laser driver 37, a semiconductor laser driver 38, an optical system driver 78, and the like. A laser controller 6 controls the entire laser processing unit 3 . The laser controller 6 is electrically connected to the galvanometer controller 35, the laser driver 37, the semiconductor laser driver 38, the optical system driver 78, and the like. The laser controller 6 is also connected to an external print information generator 2 so as to be capable of two-way communication. Also, the laser controller 6 is configured to be able to receive various pieces of information (eg, print information, control parameters for the laser processing unit 3, various instruction information from the user, etc.) transmitted from the print information creation unit 2 .

The laser controller 6 includes a CPU 41, a RAM 42, a ROM 43, and the like. The CPU 41 is an arithmetic device and control device that controls the entire laser processing unit 3 . The CPU 41, RAM 42, and ROM 43 are interconnected by a bus line (not shown) to exchange data with each other.

The RAM 42 is for temporarily storing various calculation results calculated by the CPU 41, printing pattern (XY coordinate) data, and the like.

The ROM 43 stores various programs. For example, the XY coordinate data of the print pattern is calculated based on the print information sent from the print information creation unit 2 and stored in the RAM 42 as the processed data 44. A program, a program for calculating XY coordinate data of an image drawn by the trajectory of the guide light Q and storing the data in the RAM 42, and the like are stored. In addition to the programs described above, the various programs include, for example, various delay values, the thickness, depth and number of print patterns corresponding to the print information input from the print information creation unit 2, the laser oscillator 21 A program for storing in the RAM 42 various control parameters indicating the laser output, the laser pulse width of the processing laser beam P, the scanning speed of the processing laser beam P by the galvano scanner 18, the scanning speed of the guide light Q by the galvano scanner 18, etc. There is Further, the ROM 43 stores parameters for distortion correction and status information (error information, number of times of processing, processing time, etc.) of the galvanometer scanner 18 and the laser processing device 1 .

The CPU 41 performs various calculations and controls based on various programs stored in the ROM 43 .

The CPU 41 provides processing data 44, XY coordinate data of an image drawn by the trajectory of the guide light Q, galvano scanning indicating the scanning speed of the guide light Q by the galvano scanner 18, the scanning speed of the processing laser beam P by the galvano scanner 18, and the like. Speed information and the like are output to the galvano controller 35 . In addition, the CPU 41 outputs to the laser driver 37 laser drive information indicating the laser output of the laser oscillator 21 and the laser pulse width of the processing laser beam P set based on the print information input from the print information creation unit 2. do.

The CPU 41 outputs to the semiconductor laser driver 38 an ON signal instructing the start of lighting of the visible semiconductor laser 28 or an OFF signal instructing the extinguishing of the visible semiconductor laser 28 .

The galvanometer controller 35 controls the galvanometer X axis based on each information input from the laser controller 6 (for example, the XY coordinate data of the printing pattern, the XY coordinate data of the image drawn by the trajectory of the guide light Q, the galvanometer scanning speed information, etc.). The drive angle, rotation speed, etc. of the motor 31 and galvano Y-axis motor 32 are calculated, and motor drive information indicating the drive angle and rotation speed is output to the galvano driver 36 . The galvano driver 36 drives and controls the galvano X-axis motor 31 and the galvano Y-axis motor 32 based on the motor driving information input from the galvano controller 35 to two-dimensionally scan the processing laser beam P and the guide beam Q. FIG.

The laser driver 37 drives the laser oscillator 21 based on the laser output of the laser oscillator 21 input from the laser controller 6 and the laser driving information indicating the laser pulse width of the processing laser beam P and the like. The semiconductor laser driver 38 turns on or extinguishes the visible semiconductor laser 28 based on the ON signal or OFF signal input from the laser controller 6 .

The optical system driver 78 drives and controls the optical system motor 80 based on the information input from the laser controller 6 to move the second lens 74 .

Next, the circuit configuration of the print information creating section 2 will be described. The print information creation section 2 includes a control section 51, an input operation section 55, a liquid crystal display (LCD) 56, a CD-ROM drive 58, and the like. An input operation unit 55, a liquid crystal display 56, a CD-ROM drive 58, and the like are connected to the control unit 51 via an input/output interface (not shown).

The input operation unit 55 includes a mouse and a keyboard (not shown) and the like, and is used, for example, when the user inputs various instruction information.

The CD-ROM drive 58 reads various data, various application software, etc. from the CD-ROM 57 .

The control unit 51 controls the entire print information creation unit 2, and includes a CPU 61, a RAM 62, a ROM 63, a hard disk drive (hereinafter referred to as "HDD") 66, and the like. The CPU 61 is an arithmetic device and a control device that controls the print information creation section 2 as a whole. The CPU 61, RAM 62, and ROM 63 are interconnected by a bus line (not shown) and exchange data with each other. Furthermore, the CPU 61 and the HDD 66 are connected via an input/output interface (not shown), and exchange data with each other.

The RAM 62 is for temporarily storing various calculation results and the like calculated by the CPU 61 . The ROM 63 stores various programs and the like. Further, the ROM 63 stores data such as the start point, end point, focal point, curvature, etc. of each character composed of a straight line and an elliptical arc for each type of font.

The HDD 66 stores various application software programs, various data files, and the like.

In addition, in the input operation unit 55, the user can set the speed at which the galvanometer scanner 18 scans the processing laser beam P (hereinafter referred to as the “scanning speed of the processing laser beam P”) to a first speed or a speed higher than the first speed. A slow second speed can be set. Furthermore, the setting content is stored in the RAM 62 as a control parameter for the scanning speed of the processing laser beam P. FIG. The default scanning speed of the processing laser beam P is the first speed, which is stored in the ROM 63 . In the present embodiment, the first speed is faster than the speed of changing the focal position F of the processing laser beam P in the vertical direction (Z-axis direction) (operating speed of the moving mechanism 76). The second speed is sufficiently slow compared to the speed (operating speed of the moving mechanism 76) of changing the focal position F of the processing laser beam P in the vertical direction (Z-axis direction).

The RAM 62 also stores three-dimensional shape data 64 . The three-dimensional shape data 64 is data representing the three-dimensional shape of the processing surface 8 of the object 7 and is input by the user through the input operation unit 55 or read from the CD-ROM 57 by the CD-ROM drive 58 . However, the three-dimensional shape data 64 may be measured by the three-dimensional measurement function provided in the laser processing apparatus 1, or may be created by three-dimensional CAD software application software executed by the print information creation unit 2. The CAD data may be CAD data input from the outside of the laser processing apparatus 1 via an input/output interface (not shown).

[2. Focus position of processing laser light, etc.]
In the laser processing apparatus 1, as described above, when the position of the processing surface 8 of the processing object 7 is different in the vertical direction (Z-axis direction), the focal position F of the processing laser beam P is shifted in the vertical direction (Z-axis direction). ) onto the machining surface 8 of the workpiece 7 . However, when the processing surface 8 of the processing object 7 satisfies the conditions described later and the scanning speed of the processing laser beam P is set to the first speed, the focal position F of the processing laser beam P is It is switched between the first focus position and the second focus position without being aligned with the processing surface 8 of the object 7, and moves discontinuously. The first focal position and the second focal position will be described below, including related matters.

As shown in FIG. 3, the processing laser beam P that has been two-dimensionally scanned by the galvanometer scanner 18 and has passed through the fθ lens 19 travels along the optical axis 10 from the upper side to the lower side in the Z-axis direction. and converge at the focal position F. In this embodiment, in the Z-axis direction, the side in which the processing laser beam P travels is referred to as the downstream side of the processing laser beam P, and the side opposite to the direction in which the processing laser beam P travels is referred to as the processing laser beam P. called the upstream side of

A focal depth DF of the processing laser beam P exists above and below the focal position F. In the present embodiment, the limit position of the depth of focus DF existing on the upstream side of the processing laser beam P from the focal position F is called an upstream limit position LU, and the depth of focus existing on the downstream side of the processing laser beam P from the focal position F The limit position of DF is called the downstream limit position LD. Note that the (value of) the depth of focus DF of the processing laser beam P is stored in the ROM 43 of the laser controller 6 . As the value of the depth of focus DF, for example, the Rayleigh range can be adopted, and its numerical definition is the range in the direction of the optical axis 10 where the beam diameter is √2 times or less than the minimum diameter. , it can be considered that the beam diameter does not change substantially in this range, and the influence on the processing accuracy need not be considered. However, other than the Rayleigh range may be adopted as the depth of focus DF depending on the required machining accuracy and the material of the object to be machined.

As shown in FIG. 4, the processing surface 8 of the object 7 is an uneven surface that develops on the upper side of the object 7 in the Z-axis direction. Among the positions of the processing surface 8 of the workpiece 7 in the Z-axis direction, the position on the uppermost side (that is, the most upstream side of the processing laser beam P) is defined as a first most end position ME1, and the position on the lowermost side (that is, , furthest downstream of the processing laser beam P) is defined as a second most end position ME2.

Symbol MED indicates the difference between the first extreme position ME1 and the second extreme position ME2. Reference numeral 103 indicates a position on the processing surface 8 of the object 7 where marking (printing) is performed by the processing laser beam P (hereinafter referred to as "processing position 103 for laser processing"). In this embodiment, the processing position 103 for laser processing moves over the entire region of the processing surface 8 of the object 7 in the X-axis direction. The direction indicated by the arrow 105 indicates the direction in which the processing position 103 for laser processing moves.

Reference character F1 indicates the first focal position. The first focal position F1 is assumed to be a state (hereinafter referred to as "first state") in which the upstream limit position LU of the depth of focus DF of the processing laser beam P coincides with the first extreme position ME1. It means the focal position F of the processing laser beam P. Hereinafter, the depth of focus DF in the first state will be referred to as a first depth of focus DF1 by appending the numeral "1" to its code (see FIG. 4). Furthermore, the upstream limit position LU and the downstream limit position LD of the first depth of focus DF1 are appended with the numeral "1" (see FIG. 4), and the upstream limit position of the first depth of focus DF1 It is written as LU1 and the downstream limit position LD1.

Reference character F2 indicates the second focal position. The second focal position F2 is a state in which the downstream limit position LD of the depth of focus DF of the processing laser beam P coincides with the second extreme position ME2 (hereinafter referred to as the "second state"). It means the focal position F of the processing laser beam P. Hereinafter, the depth of focus DF in the second state will be referred to as a second depth of focus DF2 by appending the numeral "2" (see FIG. 4). Furthermore, the upstream limit position LU and the downstream limit position LD of the second depth of focus DF2 are appended with the numeral "2" (see FIG. 4), and the upstream limit position of the second depth of focus DF2 It is written as LU2 and downstream limit position LD2.

[3. control flow]
The program of the laser processing method 200 represented by the flowchart of FIG. , are executed by the CPU 41 of the laser controller 6 . At that time, the three-dimensional shape data 64 and the setting contents of the scanning speed of the processing laser beam P are read from the RAM 62 of the CPU 61 of the print information generating section 2 .

However, the program of the laser processing method 200 may be executed by the CPU 61 of the print information creating section 2 . In such a case, in the processing to be described later, control is performed via the laser controller 6 when the control target is a component of the laser processing unit 3 . Also, when this program is stored in the CD-ROM 57 and read by the CD-ROM drive 58, it is executed by the CPU 61 in the same way.

This program is described below. First, the calculation process of step (hereinafter simply referred to as "S") 10 is performed. In this process, the difference MED between the first extreme position ME1 and the second extreme position ME2 on the processing surface 8 of the object 7 is calculated based on the three-dimensional shape data 64 as described above.

In the determination process S12, the difference MED between the first extreme position ME1 and the second extreme position ME2 on the processing surface 8 of the object 7 and the depth of focus DF of the processing laser beam P are compared. Here, when the difference MED between the first extreme position ME1 and the second extreme position ME2 is less than 1 times the depth of focus DF of the processing laser beam P, a fixed mode setting process S14, which will be described later, is performed. If the difference MED between the first extreme position ME1 and the second extreme position ME2 is longer than twice the focal depth DF of the processing laser beam P, another mode setting process S16, which will be described later, is performed.

On the other hand, when the difference MED between the first extreme position ME1 and the second extreme position ME2 is 1 to 2 times the depth of focus DF of the processing laser beam P, the first specific process S18 is performed. will be

In the first specifying process S18, the first focal position F1 of the processing laser beam P is specified based on the three-dimensional shape data 64, the depth of focus DF of the processing laser beam P, etc., as described above. In the second specifying process S20, the second focal position F2 of the processing laser beam P is specified based on the three-dimensional shape data 64, the focal depth DF of the processing laser beam P, etc., as described above.

In determination processing S22, it is determined whether the scanning speed of the processing laser beam P is set to the first speed or the second speed. Here, when the scanning speed of the processing laser beam P is the second speed, another mode setting process S16, which will be described later, is performed. On the other hand, when the scanning speed of the processing laser beam P is the first speed, a switching mode setting process S24 is performed.

As shown in FIG. 6, in the switching mode setting process S24, first, a first total moving distance calculation process S50 is performed. In this process, the first total moving distance is calculated based on the processing data 44 and the three-dimensional shape data 64. FIG. The first total moving distance is the total distance by which the processing position 103 for laser processing moves in the Z-axis direction at the first focal depth DF1 of the processing laser beam P assuming the first state. Specifically, on the processing surface 8 of the object 7 developed between the upstream limit position LU1 and the downstream limit position LD1 of the first depth of focus DF1, the laser processing position 103 is positioned in the XY axis directions. It is the sum of the distance by which the laser processing position 103 moves upward in the Z-axis direction and the distance by which it moves downward in the Z-axis direction (see FIG. 4).

Subsequently, a second total moving distance calculation process S52 is performed. In this process, the second total moving distance is calculated based on the processing data 44 and the three-dimensional shape data 64. FIG. The second total moving distance is the total distance by which the processing position 103 for laser processing moves in the Z-axis direction at the second focal depth DF2 of the processing laser beam P assuming the second state. Specifically, on the processing surface 8 of the object 7 developed between the upstream limit position LU2 and the downstream limit position LD2 of the second depth of focus DF2, the laser processing position 103 is positioned in the XY axis directions. It is the sum of the distance by which the laser processing position 103 moves upward in the Z-axis direction and the distance by which it moves downward in the Z-axis direction (see FIG. 4).

In the determination processing S54, the first total moving distance and the second total moving distance are compared. Here, if the first total moving distance is longer than the second total moving distance, a first timing setting process S56 is performed. In this process, at the timing when the processing position 103 of the laser processing exceeds the downstream limit position LD1 of the first depth of focus DF1, the focus position F of the processing laser beam P is either the first focus position F1 or the second focus position F2. The content of the switching mode is set so that switching to .

Specifically, as indicated by an arrow 105A in FIG. 7, at the timing when the processing position 103 for laser processing exceeds the downstream limit position LD1 of the first depth of focus DF1 from the upper side to the lower side, the processing laser beam The content of the switching mode is set so that the focal position F of P is switched from the first focal position F1 to the second focal position F2. Furthermore, as indicated by the arrow 105B in FIG. 8, at the timing when the processing position 103 of the laser processing exceeds the downstream limit position LD1 of the first depth of focus DF1 from its lower side to its upper side, the focus of the processing laser beam P The content of the switching mode is set so that the position F is switched from the second focal position F2 to the first focal position F1.

On the other hand, if the second total moving distance is longer than the first total moving distance, a second timing setting process S58 is performed. In this process, at the timing when the processing position 103 for laser processing exceeds the upstream limit position LU2 of the second depth of focus DF2, the focus position F of the processing laser beam P is either the first focus position F1 or the second focus position F2. The content of the switching mode is set so that switching to .

Specifically, as indicated by an arrow 105C in FIG. 9, at the timing when the processing position 103 for laser processing exceeds the upstream limit position LU2 of the second depth of focus DF2 from its upper side to its lower side, the processing laser beam The content of the switching mode is set so that the focal position F of P is switched from the first focal position F1 to the second focal position F2. Furthermore, as indicated by the arrow 105D in FIG. 10, at the timing when the processing position 103 of the laser processing exceeds the upstream limit position LU2 of the second depth of focus DF2 from its lower side to its upper side, the focus of the processing laser beam P The content of the switching mode is set so that the position F is switched from the second focal position F2 to the first focal position F1.

Further, when the first total moving distance and the second total moving distance are equal, a third timing setting process S60 is performed. In this process, the contents of the switching mode are set to either the contents set in the first timing setting process S56 or the contents set in the second timing setting process S58.

After the first timing setting process S56, the second timing setting process S58, or the third timing setting process S60 is performed, returning to FIG. 5, the laser machining process S26 is performed. In this process, the processing laser light P is two-dimensionally scanned by the galvanometer scanner 18 based on the printing pattern (that is, the processing data 44). Further, the focal position F of the processing laser beam P is set according to the content of the switching mode set in either the first timing setting process S56, the second timing setting process S58, or the third timing setting process S60. is switched to either the first focal position F1 or the second focal position F2, the second lens 74 of the optical system 70 is moved. In this manner, marking (printing) processing is performed on the processing surface 8 of the processing object 7 with the processing laser beam P. FIG. The laser processing method 200 then ends.

In FIG. 11, there is a mode in which the focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2 according to the content of the switching mode set in the first timing setting process S56. , indicated by line 107 . In FIG. 12, the focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2 according to the content of the switching mode set in the second timing setting process S58. Aspects are indicated by line 109 . The mode in which the focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2 according to the content of the switching mode set in the third timing setting process S60 is shown in FIG. 11 line 107 or line 109 in FIG.

Regardless of the content of the switching mode, when the focal position F of the processing laser beam P is at the first focal position F1, the laser processing position 103 that moves on the processing surface 8 of the object 7 is , between the upstream limit position LU1 and the downstream limit position LD1 of the first depth of focus DF1 that exist above and below the first focal position F1, and the focal position F of the processing laser beam P is the second focal position F2. , the processing position 103 for laser processing that moves on the processing surface 8 of the object 7 is the upstream limit position LU2 of the second depth of focus DF2 that exists above and below the second focal position F2. Since it is between the downstream limit position LD2, the quality of marking (printing) processing by the processing laser beam P is ensured.

Since the difference MED between the first extreme position ME1 and the second extreme position ME2 on the processing surface 8 of the object 7 is less than 1 times the depth of focus DF of the processing laser beam P, the fixed mode is set. When the process S14 is performed, in the fixed mode setting process S14, the content of the fixed mode is set so that the focal position F of the processing laser beam P is fixed to either the first focal position F1 or the second focal position F2. be done. Further, in the laser processing processing S26 performed thereafter, the focus position F of the processing laser beam P is set to the first focus position F1 or the second focus position F2 according to the content of the fixed mode set in the above-described fixed mode setting processing S14. The second lens 74 of the optical system 70 is moved so as to be fixed either way. Furthermore, the processing laser beam P is two-dimensionally scanned by the galvanometer scanner 18 based on the printing pattern (that is, the processing data 44). In this manner, marking (printing) processing is performed on the processing surface 8 of the processing object 7 with the processing laser beam P. FIG. The laser processing method 200 then ends.

Further, since the difference MED between the first extreme position ME1 and the second extreme position ME2 on the processing surface 8 of the object 7 is longer than twice the depth of focus DF of the processing laser beam P, another mode is set. When the process S16 is performed, in the setting process S16 of the different mode, the content of the different mode is set so that the focal position F of the processing laser beam P coincides with the position of the processing surface 8 of the object 7 to be processed. Further, in the laser processing S26 performed thereafter, the second lens 74 of the optical system 70 is moved based on the three-dimensional shape data 64, so that the focal position F of the processing laser beam P is shifted to the processing target 7. Along with being aligned on the surface 8, the processing laser light P is two-dimensionally scanned by the galvanometer scanner 18 based on the printing pattern (that is, the processing data 44). Thereby, marking (printing) processing is performed on the processing surface 8 of the processing object 7 by the processing laser beam P. FIG. The laser processing method 200 then ends.

[4. summary]
As described in detail above, in the present embodiment, when the laser processing processing S26 is performed via the switching mode setting processing S24, the focal position F of the processing laser beam P is changed to the first focal position F1 or the second focal position F1. Marking (printing) processing by the processing laser beam P is performed on the processing surface 8 of the processing object 7 while switching to one of the focal positions F2. Thus, in the laser processing apparatus 1 and the laser processing method 200 of the present embodiment, the focal position F of the processing laser beam P is set to By reducing the number of discontinuously moving locations to two, the laser processing time is further shortened while ensuring the quality of the laser processing.

In the switching mode setting process S24, the first timing setting process S56, the second timing setting process S58, the Alternatively, either the third timing setting process S60 is performed. Therefore, of the first depth of focus DF1 and the second depth of focus DF2 of the processing laser beam P, the one having the longer total distance in the Z-axis direction of the processing position 103 of the laser processing moving within those ranges is prioritized for marking. The focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2 so that (printing) processing can be performed. In this way, the laser processing apparatus 1 and the laser processing method 200 of the present embodiment reduce the number of times the focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2. As a result, the laser processing time is further reduced while ensuring the quality of the laser processing.

Further, when the scanning speed of the processing laser beam P is the second speed (determination processing S22), the laser processing processing S26 is performed via another mode setting processing S16. In such a case, the scanning speed of the processing laser beam P is the second speed that is slower than the first speed. While matching, it is possible to move the second lens 74 of the optical system 70 based on the three-dimensional shape data 64 . That is, in the laser processing apparatus 1 and the laser processing method 200 of the present embodiment, when the scanning speed of the processing laser beam P is the relatively high first speed, the focal position F of the processing laser beam P is set to the first focal position While moving in the Z-axis direction by switching to either F1 or the second focal position F2, when the scanning speed of the processing laser beam P is a relatively low second speed, the processing laser beam P is scanned by the galvanometer scanner 18. Since the focal position F of the processing laser beam P is moved in the Z-axis direction by the moving mechanism 76 while being aligned with the processing surface 8 of the workpiece 7 in accordance with the two-dimensional scanning in the XY-axis directions, the processing laser beam Optimal laser processing quality is ensured according to the scanning speed of P.

Note that when the difference MED between the first extreme position ME1 and the second extreme position ME2 on the processing surface 8 of the workpiece 7 is longer than twice the focal depth DF of the processing laser beam P, another mode Laser processing S26 is performed via setting processing S16. As a result, the laser processing apparatus 1 and the laser processing method 200 of the present embodiment can optimize the ensure the quality of laser processing.

Incidentally, the processing surface 8 of the processing object 7 is an example of the "work surface". The laser oscillation unit 12 is an example of a "laser light emitting section". The galvanometer scanner 18 is an example of an "XY-axis scanning unit". The CPU 41 or CPU 61 is an example of a "control section". Input operation unit 55 is an example of a “setting unit”. The input operation portion 55 or the CD-ROM drive 58 are examples of the "receiving portion." The three-dimensional shape data 64 is an example of "three-dimensional data of the work surface". The optical system 70 is an example of a "variable focus optical system". The processing laser beam P is an example of "laser beam". The focal position F of the processing laser beam P is an example of "the focal position of the laser beam". The first specifying process S18 is an example of a "first specifying step". The second specifying process S20 is an example of a "second specifying step". The laser processing S26 is an example of a "laser processing step".

[5. others]
It should be noted that the present disclosure is not limited to the present embodiment, and various modifications can be made without departing from the scope of the present disclosure.
For example, in the determination process S54, the number of times the laser processing position 103 exceeds the downstream limit position LD1 of the first depth of focus DF1 from the lower side to the upper side (hereinafter referred to as "first number"), and the laser The number of times the machining position 103 of machining exceeds the upstream limit position LU2 of the second depth of focus DF2 from the upper side to the lower side (hereinafter referred to as "second number of times") may be compared. In such a case, when the first number of times is greater than the second number of times, the second timing setting process S58 is performed, and when the second number of times is greater than the first number of times, the first timing setting process S56 is performed. If the number of times of the former is equal to the number of times of the latter, a third timing setting process S60 is performed. This minimizes the number of times the focal position F of the processing laser beam P is switched to either the first focal position F1 or the second focal position F2.

In the above embodiment, the first timing is the timing when the laser processing position 103 exceeds the downstream limit position LD1 of the first focal depth DF1 from the upper side to the lower side, and the laser processing position 103 is Although the timing is set to exceed the downstream limit position LD1 of the first depth of focus DF1 from the lower side to the upper side, it is not limited to this. Specifically, between the upstream limit position LU2 of the second depth of focus DF2 and the downstream limit position LD1 of the first depth of focus DF1, the specific position set closer to the downstream limit position LD1 is The focal position F may move with the timing of exceeding from the lower side and the timing of exceeding from the lower side to the upper side as the first timing. Furthermore, the specific position when the processing position 103 for laser processing is directed from the upper side to the lower side and the specific position when the processing position 103 for laser processing is directed from the lower side to the upper side may be different positions.

Similarly, in the above embodiment, the second timing is the timing when the laser processing position 103 exceeds the upstream limit position LU2 of the second focal depth DF2 from the upper side to the lower side, and the laser processing position Although 103 is the timing when the upstream limit position LU2 of the second depth of focus DF2 is exceeded from the lower side to the upper side, it is not limited to this. Specifically, between the upstream limit position LU2 of the second depth of focus DF2 and the downstream limit position LD1 of the first depth of focus DF1, a specific position set near the upstream limit position LU2 is The focal position F may be moved using the timing of moving downward and the timing of moving from the bottom to the top as second timings. Furthermore, the specific position when the processing position 103 for laser processing is directed from the upper side to the lower side and the specific position when the processing position 103 for laser processing is directed from the lower side to the upper side may be different positions.

1: laser processing device, 8: processing surface of processing object, 12: laser oscillation unit, 18: galvanometer scanner, 41: CPU, 44: processing data, 55: input operation unit, 58: CD-ROM drive, 61: CPU, 64: three-dimensional shape data, 70: optical system, 103: processing position of laser processing, 200: laser processing method, DF: depth of focus of laser light, DF1: first depth of focus, DF2: second depth of focus, F: focal position of processing laser beam, F1: first focal position, F2: second focal position, LU: upstream limit position of depth of focus, LU1: upstream limit position of first depth of focus, LU2: second focus LD: downstream limit position of depth of focus; LD1: downstream limit position of first depth of focus; LD2: downstream limit position of second depth of focus; ME1: first extreme position; : second extreme position, MED: difference between the first extreme position and the second extreme position, P: processing laser beam, S18: first specific processing, S20: second specific processing, S26: laser machining processing.

Claims (8)

a laser beam emitting unit that emits a laser beam for performing laser processing on the surface of the workpiece based on the processing data;
an XY-axis scanning unit that scans the laser light in the XY-axis directions of an orthogonal coordinate system;
a variable focus optical system that moves the focal position of the laser beam in the Z-axis direction of the orthogonal coordinate system;
a receiving unit that receives three-dimensional data of the work surface;
a control unit that drives and controls the XY-axis scanning unit and the variable focus optical system during the laser processing;
Based on the depth of focus of the laser light, the laser light indicates an upstream limit position indicating a limit position on the upstream side of the laser light and a limit position on the downstream side of the laser light in the Z-axis direction. a downstream limit position;
The control unit indicates a first extreme position indicating a position where the work surface is most upstream of the laser beam and a position where the work surface is most downstream of the laser beam in the Z-axis direction. When determining based on the three-dimensional data that the difference from the second extreme position is 1 to 2 times the depth of focus of the laser beam,
identifying the focal position of the laser beam as a first focal position when assuming a first state in which the upstream limit position of the depth of focus of the laser beam coincides with the first extreme position;
identifying the focal position of the laser beam as a second focal position when assuming a second state in which the downstream limit position of the depth of focus of the laser beam coincides with the second extreme position;
A laser processing apparatus, wherein the laser processing is performed in a switching mode in which the focal position of the laser beam is switched between the first focal position and the second focal position based on the three-dimensional data. The control unit
The processing data and Calculated based on the three-dimensional data,
The processing data and Calculated based on the three-dimensional data,
2. The laser processing apparatus according to claim 1, wherein the switching timing of the focal position of the laser beam is determined based on a comparison between the first total moving distance and the second total moving distance. The control unit
When it is determined that the first total moving distance is longer than the second total moving distance, the focal position of the laser beam at the timing when the processing position of the laser processing exceeds the downstream limit position of the first depth of focus to switch
When it is determined that the second total moving distance is longer than the first total moving distance, the focal position of the laser beam at the timing when the processing position of the laser processing exceeds the upstream limit position of the second depth of focus to switch
When determining that the first total moving distance and the second total moving distance are equal, the processing position of the laser processing is the downstream limit position of the first depth of focus or the upstream side of the second depth of focus. 3. The laser processing apparatus according to claim 2, wherein the focal position of the laser beam is switched at timing when the limit position is exceeded. The control unit
The downstream limit position of the first depth of focus, which is the depth of focus of the laser beam when the first state is assumed, is shifted from the downstream side of the laser beam to the upstream side of the laser beam. The number of times exceeding the first number is calculated based on the processed data and the three-dimensional data,
The upstream limit position of the second depth of focus, which is the depth of focus of the laser beam when the second state is assumed, is shifted from the upstream side of the laser beam to the downstream side of the laser beam. Calculate the number of times exceeding the second number based on the processed data and the three-dimensional data,
2. The laser processing apparatus according to claim 1, wherein the switching timing of the focal position of the laser beam is determined based on a comparison between the first number of times and the second number of times. The control unit
When determining that the second number of times is greater than the first number of times, switching the focus position of the laser beam at the timing when the processing position of the laser processing exceeds the downstream limit position of the first depth of focus,
When determining that the first number of times is greater than the second number of times, switching the focus position of the laser beam at the timing when the processing position of the laser processing exceeds the upstream limit position of the second depth of focus,
When determining that the first number of times and the second number of times are equal, the processing position of the laser processing exceeds the downstream limit position of the first depth of focus or the upstream limit position of the second depth of focus. 5. The laser processing apparatus according to claim 4, wherein the focal position of said laser light is switched at the timing. A setting unit for setting a scanning speed of the laser beam scanned by the XY-axis scanning unit to a first speed or a second speed slower than the first speed,
The control unit
when the scanning speed is set to the first speed, performing the laser processing in the switching mode;
6. The method according to any one of claims 1 to 5, wherein when the scanning speed is set to the second speed, the laser processing is performed in another mode different from the switching mode. The laser processing apparatus described. 7. The laser processing apparatus according to claim 6, wherein the different mode matches the focal position of the laser beam with the position of the work surface based on the three-dimensional data. A laser beam emitting unit for emitting a laser beam for performing laser processing on a work surface based on processing data, an XY-axis scanning unit for scanning the laser beam in the XY-axis directions of an orthogonal coordinate system, and a focus of the laser beam. A laser processing apparatus comprising a variable focus optical system that moves in the Z-axis direction of the orthogonal coordinate system, and a receiving unit that receives three-dimensional data of the work surface, based on the processing data and the three-dimensional data A laser processing method for performing laser processing on the work surface with the laser beam,
Based on the depth of focus, the laser beam has an upstream limit position indicating a limit position on the upstream side of the laser beam and a downstream limit position indicating a limit position on the downstream side of the laser beam in the Z-axis direction. having a limit position and
In the Z-axis direction, a first most extreme position indicating a position where the work surface is most upstream of the laser beam, and a second most extreme position indicating a position where the work surface is most downstream of the laser beam. is 1 to 2 times the depth of focus of the laser beam, a first setting step, a second setting step, and a laser processing step;
In the first setting step, the focal position of the laser beam is specified as the first focal position, assuming that the upstream limit position of the depth of focus of the laser beam coincides with the first endmost position. ,
In the second setting step, specifying a focal position of the laser beam as a second focal position, assuming a state in which the downstream limit position of the depth of focus of the laser beam coincides with the second extreme position. ,
In the laser processing step, the laser processing is performed by switching the focal position of the laser beam to the first focal position or the second focal position based on the three-dimensional data.

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