JPS6264488A - Laser beam machine - Google Patents

Abstract

PURPOSE:To observe the work position of the body to be worked without any positional deviation without performing optical correction by providing the cross line generating circuit to compose the cross line which becomes the target line of the work position of the body to be worked. CONSTITUTION:The video signal of the body to be worked transmitted from a video camera and the scanning position signal being from a control unit are inputted to a cross line generating circuit. A correction arithmetic circuit 101 operates the positional deviation in the work position and image pickup position, and the X axis target line signal generating circuit 102 and Y axis target line signal generating circuit 103 respectively generates the timing signal of the X axis target line and timing signal of the Y axis target line by the arithmetic result of the correction arithmetic circuit 101 and the video signal. A cross line composing circuit 104 forms the cross line by composing the circuit 102 and 103, and the X timing signal and Y timing signal and the video signal. The intersection of the cross line on a video monitor thus thus shown the work position by the laser beam all the time and the image enlarging the peripheral part of the work position is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a laser processing apparatus, and more particularly to a laser processing apparatus equipped with an imaging device that displays the processing position of a workpiece on a video monitor.

[Conventional technology]

Conventionally, in laser processing equipment equipped with a galvanometer-type beam point non-yonning device that performs high-speed positioning and scanning of the processing position of the workpiece, the processing position of the workpiece cannot be observed by magnifying it; The observation light that returns through the opposite path from the processing light is separated by a dichroic mirror placed between the beam positioning device and the laser light source.

An imaging device that performs 1-in-1 imaging is used.

[Problems that Hatsushi attempts to solve] By the way, in the case of the conventional workpiece imaging device described above, since the observation light from the workpiece passes through the f-theta lens,
Scan the area other than the center of the f-θ lens and f? :ny is f-
Due to the chromatic aberration of the θ lens, near-infrared ′#-, ″7- certain N
d: Positional deviation from the YAG laser beam occurs.

This positional deviation is 2. For example, the machining range is 80X80ii1
If it is 111 degrees, it will be about 0.5 ram, which is a large value that cannot be ignored in terms of processing accuracy. Therefore, it becomes difficult to read the coordinate data of the processing position directly from the imaging position.

In order to eliminate this positional deviation, light of multiple wavelengths is
The lens system must be designed to include a correction for so-called "color discoloration" that converts the same angular displacement into the same positional displacement. However, the design of the double series itself was extremely difficult, and it was not possible to completely correct the position deviation.
Another problem is that the lens system becomes expensive.

SUMMARY OF THE INVENTION An object of the present invention is to provide a laser device equipped with an imaging device that can observe the processing position of a workpiece without any positional deviation, while eliminating the above-mentioned drawbacks.

[Failure to solve the problem]

A laser device having a workpiece imaging device according to the present invention includes a laser light source and a galvanometer-driven scanning system that scans the laser light from the laser light source to the processing position of the workpiece (and changes the incident angle of the laser light).
2nd place: a beam positioning device having an f-0 lens that converts a displacement in the angle of incidence into a displacement in position and condenses the light; l
- arranged between the laser beam and the laser beam reflecting the laser beam;
a dichroic mirror that transmits illumination light of the workpiece whose main component is visible light; a video camera that images the processed surface of the workpiece via the beam positioning device and the dichroic mirror; and the f-θ lens. 7. Calculate the positional deviation between the laser beam and the observation beam due to chromatic aberration using the scanning position signal; a crosshair generation circuit that combines a target line of a processing position according to the positional deviation with a video signal from the video camera; a video monitor that images the combined signal; the laser light source, the beam positioning device, and the crosshair generation circuit. It has a control unit that drives and controls the circuit.

〔Example〕

Next, the present invention will be explained with reference to one drawing.

First, referring to FIG. 1, the laser beam 15 emitted from the Nd:YAG laser light source 1 is expanded in beam diameter by a beam expander 2, and then reflected by a dichroic mirror 8 that reflects near-infrared light. Ru. The laser beam 15 is reflected and scanned by an X-axis scanning mirror 3 a driven by a galvanometer 3 , further reflected and scanned by a Y-axis scanning mirror 4 a driven by a lupanometer 4 , and then focused by an f-θ lens 5 . Note that these galvanometers 3. X-axis scanning mirror 3a
.

be done. The laser beam 15 condensed by the f-theta lens 5 is focused on the workpiece 7 and processes the workpiece 7. Note that this workpiece 7 is illuminated by the illumination 6.

On the other hand, the viewing light (visible light) 16 from the workpiece 7 takes the opposite path to the laser light (YAG laser processing light) 15,
f-theta lens5. Visible light passes through the scan mirror 4a and the ditaloic mirror 8 through which visible light is transmitted, and is separated from the path of the YAG laser light 15. This observation light 16 is focused by a lens 9, converted into a video signal by a video camera 10, and input to a crosshair generation circuit 11.

The crosshair generation circuit 11 synthesizes a vertical line serving as a Y-axis target line and a horizontal line serving as a Y-axis target line with the above-mentioned video signal. The combined position of the two target lines is controlled by a scanning position signal from the control unit 13, as will be described later. A video monitor 12 displays a composite video signal of the two target lines. Moreover, the control unit 13
It controls the on/off movement of the laser light source 1, the drive control of the galvanometer type beam positioning device, and the control of the crosshair generation circuit 11.

Next, referring also to FIGS. 2(,) and (b), the processing position when the galvanometer type beam positioning device scans the center of the processing range of the workpiece is the center of the screen of the video camera 12. The video camera IG is aligned so that the intersection of the X fine target line 21 and the Y fine target line 22 indicates one machining position 25.

X thin target line 21. Align the Y thin target line 22.

Here, the X thin target line 21. The outline of the synthesis of the Y minutiae # lines 22 will be explained with reference to FIGS. 3(,) and (b).

Based on the synchronization signal of the horizontal synchronization signal 201 included in the video signal 202 as shown in FIG.

After one hour, the output of the video signal 202 is set to low level. That is, by inserting a black signal into the video signal 202 after one hour, the X-axis reference line signal 206 is synthesized with the video signal. Further, as shown in FIG. 3<b), the thousand synchronization signals 204 of the horizontal synchronization signal 204 are activated after n cycles of the horizontal synchronization signal 204 based on the synchronization pulse of the vertical synchronization signal 203 included in the video signal 205. By inserting one cycle of the black signal into the video signal 205, the YI111 target line signal 207 is synthesized with the video signal. Then, if we control the above time T, xg line of sight composite position]?
By controlling 5 and the above n, the composite position of Y@target line can be controlled.

Referring again to FIGS. 2(a) and (b), FIG. 2(b)
), the positional deviation dx, dy (shown in Figure 7(,)) on the video monitor when scanning the processing position of the workpiece by ΔX, Δy from the center position 28 is the following (1 ) and equation (2).

dx=f(ΔX, Δy): a1Δx+a2ΔX
+a3Δx3+b, Δy+b2Δy +b3Δy3
...(1) dy-g(ΔX, Δy) YuC
1Δx+C2Δx +c3Δx30d, Δy10d2Δy
+d3Δy3...(2) However, j
alj C2j C3f bj t b2 t b3
j C1jQ2 s C3y dl y d2 t d
3 is a unique constant.

Positional deviation dx shown by equations (1) and (2),
dy(t Therefore, the parameters T and n for the composition of the X thin target line and the composition of the Y thin target line are expressed by the quadratic equation (3) and the
4) It is shown by Eq.

T=αf(ΔX, Δy) + T, , C
3) n=βf(ΔX, Δy')+n...(4
) However, α and β are fixed constants tTQy and n. is a constant for composing the X-axis and Y fine target lines at the center position of the screen.

Next, the crosshair generation circuit will be explained with reference to FIG. The crosshair generation circuit receives the video signal of the workpiece from the video camera and the scanning position signal from the control unit as described above.

The correction calculation circuit 101 calculates the positional deviation between the processing position and the imaging position, and the calculation result of the correction calculation circuit 101 and the video signal are used to generate a +
This is called a timing signal. ) and Y thin target line timing signals (hereinafter referred to as Y timing signals), an X thin target line signal generation circuit 102 and a Y thin target line signal generation circuit 103, and an X timing signal and a Y timing signal 18.
and a crosshair synthesis circuit 104 that synthesizes the signal and the video signal to form a crosshair.

As described above, since the cross line generation circuit is equipped with the cross line generating circuit 1 which synthesizes the cross line which becomes the target line of the processing position of the workpiece, the processing position can be scanned to a position other than the center of the f-theta lens using the beam positioning device. Even though.

The intersection of the crosshairs on the video monitor always indicates the position processed by the laser beam, and an enlarged image of the peripheral area of the processed position can be obtained. Therefore, it is possible to read the coordinate data of the processing position of the workpiece directly from the imaging position on the video monitor without adding optical correction called "color discoloration". In this way, there is no need to perform optical correction due to "color discoloration."

The f-theta lens can be designed for monochromatic YAG laser light, and angle-position conversion and focusing of the YAG laser light can be performed at low cost.

〔Effect of the invention〕

As explained above, according to the laser processing apparatus of the present invention, there is no need to design a lens system including correction for "discoloration", and positional deviation can be completely corrected. The effect tends to be

[Brief explanation of drawings]

FIG. 1 is a diagram showing a schematic configuration of a laser processing device according to the present invention, and FIGS. 2 (,) and (b) are diagrams schematically showing an image obtained by the laser processing device of the present invention and a workpiece, respectively. Diagrams schematically showing things, Figures 3 (a) and (b)
4 is a diagram for explaining the outline of cross-hair synthesis, and FIG. 4 is a block diagram showing a cross-hair synthesis circuit used in the laser processing apparatus according to the present invention. 1...Nd: YhG laser light source, 2...beam expander, 3...X-axis galvanometer, 3a.
...X-axis scanning mirror, 1...Y-axis galvanometer, 4
a...Y-axis scanning mirror, 5...f-θL/lens, 6.
...Lighting, 7.Workpiece, 8.Gook clock mirror, 9.Condensing lens. 10... Video camera, 11... Crosshair generation circuit. 12... Video monitor, 13... Control unit, 1
5... YAG laser processing light, 16... Observation light of the workpiece. 20... Video monitor, 21... Y-axis layer mark line (center position) 222... X-axis layer mark line (center position), 23...
・Y cuff mark line (outer circumferential position), 24...X-axis layer mark line (outer circumferential position), 25...imaged processing position (center position)
. 26... Imaged processing position (outer circumferential position), 101.
...Correction calculation circuit, 102...X-axis layer mark line signal generation circuit, 103...Y-axis layer mark line signal generation circuit, 104...
・Crosshair synthesis circuit, 105...Scanning position signal, 106
. . . video signal, 107 . . . crosshair composite video signal. 201...Horizontal synchronization signal, 202...Video signal. 203...Vertical synchronization signal, 204...Horizontal synchronization signal. 205...Video signal, 206...X-axis layer gauge line signal. 207...Y-axis load mark signal, 27...Workpiece, 2
8...Scanning position (center position), 29...Scanning position (
Outer circumference position) Figure 1 Section 2

Claims (1)

[Claims] 1. A laser light source, a galvanometer-driven beam scanner that scans the laser light from the laser light source to the processing position of the workpiece, and proportional to the displacement of the incident angle of the laser light,
a beam positioning device including an f-theta lens that converts the incident angle displacement into a positional displacement and condenses light; and a beam positioning device disposed between the laser light source and the beam positioning device that reflects the laser beam. , a dichroic mirror that transmits illumination light of the workpiece whose main component is visible light; a video camera that images the processed surface of the workpiece via the beam positioning device and the dichroic mirror; - A crosshair that calculates a positional deviation between the laser beam and the observation light due to chromatic aberration of the θ lens using a scanning position signal, and synthesizes a target line of the processing position according to the positional deviation with a video signal from the video camera. A laser processing apparatus comprising a workpiece imaging device having a generation circuit, a video monitor that images the composite signal, and a control unit that drives and controls the laser light source, beam positioning device, and crosshair generation circuit.