JPH11119073A - Automatic optical axis control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To correct a laser beam accompanied by a deviation of an incident angle, and eliminate the need for adjustment man-hours and software development man-hours. SOLUTION: The automatic optical axis control device of the present invention includes a light detecting unit 10 for detecting whether or not an optical axis L of a laser beam passes a fixed point P1, and an optical axis L passing through a fixed point P2. A light detecting unit 12 for detecting whether or not the optical axis L is being driven, a driving unit 14 for changing the direction of the optical axis L, and an optical axis L passing through the fixed points P1 and P2 based on detection signals from the light detecting units 10 and 12. And a control unit 16 for adjusting the optical axis L via the drive unit 14. Since the optical axis L is detected at two locations as described above, it is possible to correct a laser beam accompanied by a deviation in the incident angle.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic optical axis control device used in a laser application apparatus for automatically adjusting the optical axis of a laser beam.

[0002]

2. Description of the Related Art In a conventional laser device, an optical axis adjusting mirror is provided inside in the case where an optical axis shift occurs. Conventionally, as the optical axis adjusting mirror, those which are manually adjusted, those which are adjusted by software, and those which are adjusted by a two-axis driving actuator disclosed in Japanese Patent Application Laid-Open No. 5-66832. .

[0003]

However, there is a problem in that manual adjustment requires too much adjustment man-hour and software-based adjustment requires too much software development man-hour.

Further, since the two-axis drive actuator adjusts the optical axis so that it passes through only one specific point, there is a problem that it is impossible to correct a laser beam accompanied by a deviation of the incident angle. Therefore, the two-axis drive actuator can be applied only to a laser application device using a laser beam without a deviation of the incident angle.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an automatic optical axis control apparatus which can correct a laser beam accompanied by a deviation of an incident angle, and can eliminate the need for man-hours for adjusting and software development.

[0006]

According to the present invention, there is provided an automatic optical axis control device, comprising: a first light detection unit for detecting whether an optical axis of a laser beam passes a first fixed point; A second light detection unit that detects whether the optical axis passes through a second fixed point, a driving unit that changes the direction of the optical axis, and the first light detection unit.
And a control unit that adjusts the optical axis via the drive unit such that the optical axis passes through the first and second fixed points based on a detection signal of the second light detection unit. Things.

According to the present invention, the light detecting units are arranged at two positions on the optical axis, and the optical axis shifts in the X-axis direction and the Y-axis direction are detected, for example, and the detection signals are fed back to the driving unit. To correct the optical axis deviation.

[0008] Even when the incident angle of the laser beam is shifted, the optical axis is monitored at two positions, so that the shift amount can be detected. Therefore, it is possible to correct the deviation of the incident angle so as to match the normal optical axis. In addition, since the optical axis can be adjusted in real time by the control unit, it is not necessary to adjust manually or by software.

[0009]

FIG. 1 is an optical path diagram showing an embodiment of an automatic optical axis control device according to the present invention. Hereinafter, description will be made based on this drawing.

The automatic optical axis control device according to the present embodiment includes a light detecting unit 10 for detecting whether or not an optical axis L of a laser beam passes a fixed point P1, and an optical axis L passing through a fixed point P2. A light detecting unit 12 for detecting whether or not the optical axis L is being driven, a driving unit 14 for changing the direction of the optical axis L, and an optical axis L passing through the fixed points P1 and P2 based on detection signals from the light detecting units 10 and 12. And a control unit 16 for adjusting the optical axis L via the drive unit 14.

The light detecting section 10 is provided with a laser beam (optical axis L).
A beam split mirror 101 for splitting the reflected light R1 into transmitted light T1 and reflected light R1, and a four-segment photodetector 102 for receiving the reflected light R1. The light detection unit 12 includes a beam split mirror 121 that splits the transmitted light T1 into the transmitted light T2 and the reflected light R2, and a four-segment photodetector 122 that receives the reflected light R2.

The driving unit 14 has an X axis and a Y axis orthogonal to each other.
A gimbal adjustment mechanism for rotating the optical axis L about the axis,
A mirror 20 for reflecting a laser beam (optical axis L), and a motor 20 for rotating the mirror 20 about the X axis and the Y axis
x, 20y, a mirror 22 that further reflects the laser beam (optical axis L) reflected by the mirror 20, and X
Motors 22x and 22y that rotate about the axis and the Y axis.

The laser beam (optical axis L) is transmitted to the mirror 20,
After being reflected back at 22, it is partially reflected by beam split mirrors 101 and 121 at fixed points P 1 and P 2, respectively. The reflected light R1, R2 is received by the quadrant photodetectors 102, 122 to detect the optical axis L.

FIG. 2 is a block diagram showing an example of a control system in the automatic optical axis control device of FIG. Hereinafter, description will be made based on this drawing.

X- and Y-axis detection signals 102a and 122a detected by the four-divided photodetectors 102 and 122
Is converted into an angle correction amount of the mirrors 20 and 22 by the gain control circuit 162 via the differential amplifier circuit 161, and is output to the motors 20x, 20y, 22x and 22y via the motor drive circuit 163. You. Also,
The comparator circuit 164 always detects the optical axis shift amount by comparing the detection signals in the X and Y axis directions after passing through the differential amplifier circuit 161 with a reference value. The timing control circuit 165 includes a gain control circuit 162 for each axis.
The sequence for correcting the optical axis shift is generated by generating the timing for converting the gain into the optical axis.

FIG. 3 is a chart showing an example of a control sequence for correcting an optical axis shift in the automatic optical axis control device of FIG. Hereinafter, description will be made with reference to FIGS.

When the optical axis shift occurs, the detection signal 102a for the X and Y axes at the fixed point P1 and the fixed point P2
It is assumed that the detection signals 122a for the X and Y axes in the above state are in the respective states. Then, the detection signal 102
An output signal is output to the motors 20x and 20y so that a is displaced in the reverse direction by a displacement ΔY / 2 which is half of the displacement ΔY. Subsequently, output signals are output to the motors 22x and 22y so that the detection signal 122a is displaced to the 0 level. At this time, if the level of the detection signal 102a is not 0, the process of → is repeated again. Detection signal 102
If the levels of a and 122a both become 0 (state),
The correction ends.

[0018]

According to the automatic optical axis control device according to the present invention, the first optical detector for detecting whether or not the optical axis of the laser beam passes through the first fixed point, A second light detection unit that detects whether or not the light passes through a second fixed point;
A drive unit for changing the direction of the optical axis, and adjusting the optical axis via the drive unit based on detection signals from the first and second light detection units so that the optical axis passes through the first and second fixed points. Since the optical axis is detected at two locations by providing the control unit, the laser beam accompanied by the deviation of the incident angle can be corrected. Therefore, the present invention can also be applied to a laser application device that uses a laser beam with a deviation of the incident angle. In addition, the man-hour for adjusting the optical axis by hand and the man-hour for developing the software for adjusting the optical axis can be eliminated.

A first mirror for reflecting the laser beam, a first motor for rotating the first mirror about the X axis and the Y axis, and further reflecting the laser beam reflected from the first mirror The first mirror and the motor, the second mirror, and the second mirror are configured as a drive unit including a second mirror to be rotated and a second motor that rotates about the X axis and the Y axis. Since the optical axis can be translated in combination with a motor, the laser beam can be corrected even for a variety of deviations of the incident angle.

[Brief description of the drawings]

FIG. 1 is an optical path diagram showing an embodiment of an automatic optical axis control device according to the present invention.

FIG. 2 is a block diagram showing an example of a control system in the automatic optical axis control device of FIG.

FIG. 3 is a chart showing an example of a control sequence for correcting an optical axis shift in the automatic optical axis control device of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 1st light detection part 12 2nd light detection part 14 drive part 16 control part 20 1st mirror 20x, 20y 1st motor 22 2nd mirror 22x, 22y 2nd motor 101 1st beam split Mirror 102 First quadrant photodetector 121 Second beam split mirror 122 Second quadrant photodetector L Optical axis P1 First fixed point P2 Second fixed point R1 First reflected light R2 Second reflection Light T1 First transmitted light T2 Second transmitted light

Claims (4)

[Claims] A first light detection unit that detects whether an optical axis of the laser beam passes through a first fixed point; and whether the optical axis passes through a second fixed point. A second light detection unit for detecting a direction of the optical axis, a drive unit for changing the direction of the optical axis, and the first and second fixed positions of the optical axis based on detection signals from the first and second light detection units. A control unit for adjusting the optical axis via the driving unit so as to pass through a point. A first beam splitting mirror for splitting the laser beam into a first transmitted light and a first reflected light; and a first light splitting mirror for receiving the first reflected light. A four-segment photodetector, wherein the second light detection unit is configured to split the first transmitted light into a second transmitted light and a second reflected light, a second beam split mirror, 2. The automatic optical axis control device according to claim 1, further comprising a second quadrant photodetector that receives the two reflected lights. 3. 3. The automatic optical axis control device according to claim 1, wherein the drive unit is a gimbal adjustment mechanism that rotates the optical axis about an X axis and a Y axis that are orthogonal to each other. 4. The gimbal adjustment mechanism includes: a first mirror for reflecting the laser beam; a first motor for rotating the first mirror about the X axis and the Y axis; 4. The apparatus according to claim 3, further comprising a second mirror that further reflects the laser beam reflected by the mirror, and a second motor that rotates the second mirror about the X axis and the Y axis. Automatic optical axis control device.