JPS63130294A - Laser beam machine - Google Patents

Abstract

PURPOSE:To obtain the reproducibility of a position stabilized at all times by scanning the recognition mark provided on a loading base loading the body to be worked and correcting the projecting position by detecting the dislocation of the projecting position of a laser light from the dislocation of this recognition mark. CONSTITUTION:The laser light 21 projected from the laser light source 1 for working is made incident on a beam positioner 3, condensed by a condensing lens 4 via a Y axial scanner mirror 32 and condensed on the body 8 to be worked on a loading base 7. On the other hand, the reflection light 22 from the projection position of the laser light 21 is made incident on a photoelectric conversion device 9. At this time not only the work point of the body 8 to the worked but also three recognition marks located on the right angled corner of the loading base 7 are imaged on the optical detecting face of the transducing device 9. The output from the device 9 is inputted to a preprocessing part 10 for removing the noise caused from this output and making it bivalent by comparing this output with a reference signal. A control part 11 performs the positional control of both axes XY via a driving part 12, performing the processing of the data made bivalent fed from the preprocessing part 10, the calculation of the correction amt. of the position, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a laser processing device, and more particularly to a laser processing device used for laser trimming, laser marking, and the like.

BACKGROUND ART Conventionally, in laser processing devices such as laser trimming and laser marking, a galvanometer is often used as a drive source for a beam positioner that determines the irradiation position of laser light. Galvanometers have a simple structure and are capable of high-speed positioning, so they are often used as a driving source.

Such a conventional sea 11 processing apparatus uses a galvanometer as a drive source for the beam positioner, and therefore has a disadvantage of poor positioning accuracy because the rotation angle of the galvanometer varies due to temperature drift.

Therefore, during laser processing, a guide light is used, and the position is corrected manually by manual operation while visually observing the guide light, and the gain correction is performed after processing the workpiece and then measuring its dispersion. Corrections were made manually.

Purpose of the Invention The present invention has been made in order to eliminate the drawbacks of the conventional ones as described above, and is capable of automatic offset correction and gain correction of the laser beam irradiation position, and constantly stable position repeatability. The purpose is to provide a laser processing device that can perform

Composition of the Invention A laser processing apparatus according to the present invention is a laser processing apparatus that performs laser processing by moving the irradiation position of a laser beam on a workpiece, and includes a scanning light beam coaxially with the optical axis of the laser beam. A scanning means having an optical axis and scanning a recognition mark provided on a stage on which the workpiece is mounted, and detecting a deviation of the irradiation position from a deviation of the recognition mark scanned by the scanning means. The present invention is characterized in that a detecting means for detecting is provided, and the irradiation position is corrected according to the detection result of the detecting means.

Embodiment Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

In the figure, one embodiment of the present invention shows a processing laser light source 1
, the laser beam 21 is reflected, and the reflected light 2 from the workpiece 8 is reflected.
2, a two-dimensional scanning beam positioner (hereinafter referred to as beam positioner) 3, a condenser lens 4, a folding mirror 5, an illumination lamp 6, and a workpiece 8.
and the reflected light 2 transmitted from the mirror 2.
2 as scanning light, a two-dimensional self-scanning photoelectric conversion device (referred to as a photoelectric conversion device) 9, a preprocessing section 10, a control section 11, and a driving section 12.

The beam positioner 3 has an X-axis scanner mirror 31 and a Y i
t scanner mirror 32.

First, laser light 21 emitted from the processing laser light source 1
is reflected by mirror 2 and is incident on beam position 3. X of beam positioner 3 @ scanner mirror 3
1 and the Y-axis scanner mirror 32 are individually attached to the shaft of a galvanometer (not shown), and have the roles of optical scanning for X@ and Y-axis outputs, respectively.

Laser light 21 emitted from Y-axis scanner mirror 32 is focused by condenser lens 4 , reflected by folding mirror 5 , and focused onto workpiece 8 on stage 7 .

On the other hand, reflected light 22 from the irradiation position of the laser beam 21 passes through the same optical path as the laser beam 21, passes through the mirror 2, and enters the photoelectric conversion station 9. At this time, not only the processing point of the workpiece 8 but also the 3g
The recognition mark is also imaged on the light receiving surface of the photoelectric conversion device 9.

The output from the photoelectric conversion device 9 that converts an image signal into an electrical signal is input to a preprocessing unit 10 that removes noise from this output, compares this output with a reference signal, and binarizes the output. The control unit 11 performs position control in both the X and Y axes via the drive unit 12, and has the role of processing binarized data from the preprocessing unit 10, calculating a position correction field, and the like.

FIG. 2 is a plan view of the stage 7 shown in FIG. 1. In the figure, there are three recognition marks A and B on the stage 7.

A right angle corner 71 having C is provided, and the right angle corner 71
A workpiece 8 is mounted in contact with. The stage 7 has a scanning area 72 of the beam positioner 3, an origin 0 of the scanning area 72, a processing area 73, and the processing area 7.
3 workpiece origins P are provided.

The coordinates of the recognition mark A are (xa, ya), and these coordinates are indicated by offset 1-values from the origin O.

The mark of recognition mark B is (Xa + = 1), and the coordinates of the recognition mark C are (xa, ya + yg), and yg
indicates the Y-axis gain.

Normally, due to temperature drift of the rotating shaft of the galvanometer, the offset values xa, ya and the gains xa, y9 change in response to temporal temperature changes.

FIG. 3 is a diagram showing the bit patterns of the recognition marks Δ, B, and C in FIG. 2. In the figure, bit pattern 91.
92 is a recognition mark A obtained by the reflected light 22 in the photoelectric conversion device 9 before and after the drift, respectively.
, B, and C are scanned. When certain data is specified, before drift, the photoelectric conversion device 9 obtains the bit pattern 91, but after drift, even if the data is specified in the galvanometer, the irradiation position of the laser beam 21 will be changed according to the data. However, the photoelectric conversion device 9 obtains a bit pattern 92. J3, in the figure, Xm, yll are drift 1~
Represents the previous central brokerage, xn.

yn represents the center position after drift, and one section represents a 1-bit element.

Position correction in an embodiment of the present invention will be explained using FIGS. 1 to 3.

First, as shown in FIG. 2, a recognition mark A is created in advance.

B and C are determined in advance, and at a certain point, the X-axis scanner mirror 31 and Y-axis scanner mirror 32 are positioned at each recognition mark A, B, and C. Recognition mark △, B.

The center points xm and ym of the bit pattern 91 of C are determined.

For example, let the offset value and gain obtained at that time be X aO, Y aO, X go, Y (10), respectively.

Next, after an arbitrary period of time has elapsed, for example, when the laser rimming process for 10 glue plates has been completed, the XlN1 scanner mirror 31 and the Y-axis The scanner mirror 32 is positioned. Then, when the center points xn and yn of the pick-pattern 92 of Δ, B, and C of each recognition mark 151 generated from the photoelectric conversion device 9 are found, the offset values are X al, Y
al, and the gain is xg1. Y (denoted by 11. Therefore, the respective temporal drifts of the X111 scanner mirror 31 and the Y-axis scanner mirror 32 are off-sera]・values are (XaO-Xal), (+'aO-Ya1
), and the gain is (X(10-X(II), (Y
go-Ycll). That is, if these drift patterns are fed back to the drive unit 12 as correction ω,
The positional deviation of the beam positioner 3 is corrected. here,
Gain drift t is corrected according to distance. In addition,
The correspondence between the resolution of the photoelectric conversion device 9 and the resolution of the galvanometer is determined in advance as data and input to the control unit 11.

In this way, the recognition marks A, B, and C9r are provided on the stage 7 on which the workpiece 8 is mounted, and the photoelectric conversion device 9 scans the recognition marks A, B, and C. By calculating the deviation value of the beam positioner 3 from the bit patterns 91 and 92 generated by p, and correcting the galvanometer that drives the beam positioner 3 based on this value, the offset value 1 to the value of the irradiation position of the laser beam 21 is calculated. It is also possible to automatically correct the gain, and it is possible to always perform stable position recirculation without worrying about temperature drift with respect to the rotation angle of the galvanometer.

Furthermore, by using this photoelectric conversion device 9, it is possible to obtain the coordinates of the processing point, so it is possible to add a teaching function like an NC processing machine without manually inputting coordinate data. becomes.

DETAILED DESCRIPTION OF THE INVENTION According to the present invention, the recognition mark provided on the stage on which the workpiece is placed is scanned, and the deviation of the laser beam irradiation position is determined from the deviation of the recognition mark. By detecting and correcting the irradiation position according to the detection result, it is possible to automatically correct the offset and gain of the laser's intended irradiation position, and always obtain stable position repeatability. It has the effect of being able to.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing one embodiment of the present invention, and FIG.
FIG. 3 is a plan view of the stage shown in FIG. Explanation of symbols of main parts 3... Two-dimensional scanning beam positioner 7... Stage 9... Two-dimensional self-scanning photoelectric conversion device

Claims (2)

[Claims] (1) A laser processing device that performs laser processing by moving the irradiation position of a laser beam on a workpiece, which has an optical axis of scanning light coaxial with the optical axis of the laser beam, and A scanning means for scanning a recognition mark provided on a stage on which a workpiece is mounted, and a detection means for detecting a shift in the irradiation position from a shift in the recognition mark scanned by the scanning means, A laser processing apparatus characterized in that the irradiation position is corrected according to the detection result of the detection means. (2) The recognition marks are provided at at least three locations on each corner of the document table, and by detecting the displacement of each of these recognition marks, the displacement of the irradiation position in the X-axis direction and the Y-axis direction can be detected. The laser processing apparatus according to claim 1, characterized in that the laser processing apparatus is adapted to be modified.