JPH0521884A - Gas laser tube device - Google Patents

Abstract

PURPOSE:To provide a gas laser tube device wherein variations of a radiation direction of an output laser beam can automatically be corrected highly accurately. CONSTITUTION:A gas laser tube device includes a plurality of laser beam position detector, parts 35, 36 provided at a predetermined interval frontally of an output mirror 22. Electric signals corresponding to laser beam positions yielded by the laser beam position detector parts are computed to control mirror inclination adjusting mechanisms 25, 26, 27, 28 or control the movement of the optical axis of a laser tube 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas laser tube device, and more particularly to an improvement of a device provided with a mechanism for suppressing the direction variation of its output laser beam.

[0002]

2. Description of the Related Art Generally, a gas / laser tube device has a gas / laser tube fixed to a support frame of a laser head portion, and has high reflection on each mirror fixing plate arranged on both sides of the discharge path. The mirror and the output mirror are fixed to each other, and these are fixed to the support frame. Energizing power is supplied to the laser tube from a power supply unit. In operation, the laser medium is excited by the energizing power, and the light is amplified by the high reflection mirror and the output mirror that form the optical resonator. Part of the light passes through the output mirror and is extracted as laser light.

In such a gas laser tube device,
The support frame and the mirror fixing plate may be deformed due to heat generated from the laser tube during operation, or the tilt of each mirror may change and the laser light output level may drop and the laser beam emission direction may fluctuate. . In order to automatically correct the tilt of this mirror, a pulse motor for mirror tilt adjustment is provided on at least one of the mirror fixing plates, and the pulse motor is driven and controlled by the output electric signal corresponding to the laser beam split by the beam splitter. Devices have also been developed that are configured to control the optical parallelism.

[0004]

A part of the output laser beam is split by a beam splitter, photoelectrically converted by a light receiving element, and the discharge current of a power supply control circuit is controlled by the output electric signal to keep the laser output level constant. It's relatively easy to keep. However, it is not easy to eliminate the variation in the emission direction of the output laser beam. This is because the discharge path of the laser tube and the optical axis of the optical resonator mirror change in an oblique direction, and there is also a change in parallel movement, which cannot be accurately corrected by the photoelectric conversion signal from one light receiving unit. .
The present invention eliminates the above-mentioned inconvenience, and a gas capable of automatically correcting fluctuations in the radiation direction of the output laser beam with high accuracy.
An object is to provide a laser tube device.

[0005]

According to the present invention, a plurality of laser beam position detectors are provided at the tip of an output side mirror at predetermined intervals, and the laser beam positions obtained by these laser beam position detectors are dealt with. A gas / laser tube device configured to arithmetically process an electric signal to drive a mirror tilt adjusting mechanism to adjust the tilt of at least one mirror.

[0006]

According to the present invention, a plurality of laser beam position detectors are provided at predetermined intervals, and the laser beam position signals obtained by these laser beam position detectors are arithmetically processed to drive the mirror tilt adjusting mechanism. Therefore, the variation of the output laser beam in the radiation direction can be automatically corrected with high accuracy.

[0007]

Embodiments will be described below with reference to the drawings. The same parts are denoted by the same reference numerals.

A gas laser tube apparatus according to an embodiment of the present invention has a schematic structure shown in FIG. That is, the laser head portion 31 accommodates a laser tube 11 having a gas discharge path, and a high reflection mirror is provided on one side with the discharge thin tubes 12 and 13 interposed therebetween.
21 and an output mirror 22 on the other side. The high reflection mirror 21 is a mirror tilt adjusting mechanism 25, 2 such as a pulse motor.
The 6 allows the horizontal and vertical tilt to be adjusted. Similarly, the output mirror 22 is adjusted in tilt in the horizontal and vertical directions by mirror tilt adjusting mechanisms 27 and 28 such as pulse motors. A trigger circuit unit 32 is connected to the anode of the laser tube 11. Therefore, a plurality of beam splitters 33, 34 are arranged at predetermined intervals on the output laser optical path, and light receiving portions 35, 36 each made of a photoelectric conversion element are installed on each branch optical path. In the power supply section 37, the commercial power supply is a rectifier circuit section.
38, smoothing circuit 39, heater / transformer 40 and discharge voltage
Connected to the current stabilization circuit 41, their outputs are laser tubes.
Supplied to 11. The electric signal indicating the output laser light level of one light receiving portion 35 is also supplied to the control circuit 42 to control the discharge voltage / current stabilizing circuit 41.

The electric signals output from the two light receiving sections 35 and 36 are supplied to the A / D converter section 44 of the laser beam position control section 43.
Comparing arithmetic circuit section, that is, microcomputer section
The pulse signal is supplied to the pulse motor 45, and its output signal is supplied to the motor power supply 46 for driving the pulse motor to drive and control the pulse motors 25, 26, 27 and 28. The signal from the microcomputer unit 45 is also transmitted to the laser tube 11 and the mirrors 21 and 22.
Is supplied to a movement control circuit unit 47 for controlling movement of the laser beam in a direction parallel or oblique to the horizontal plane, and the movement control circuit unit 47 is supplied to the movement control elements 48 and 49 of the laser head unit 31.

The laser head section 31 has the structure shown in FIGS. That is, a laser tube 11 having a gas discharge path inside has discharge capillaries 12 and 13 extending on both sides and having Brewster windows, and a resonator frame assembled on a support base 14.
It is fixed at 15. Fixed plates 16 and 17 are vertically installed on both sides of the resonator frame 15, and movable plates 19.20 are held on the fixed plates 16 and 17 through a plurality of plate springs 18, respectively. One movable plate
A high reflection mirror 21 is fixed to the center of 19 and an output mirror 22 is fixed to the center of the other movable plate 20. Further, motor support plates 23 and 24 are fixed to the support base 14, and two motor support plates and two pulse motors 25 and 26,
And 27,28 are installed. The pulse motors 25, 26 connected to one movable plate 19 are an X-axis adjusting motor for moving the high reflection mirror 21 in the X-axis and Y-axis directions, and a Y-axis adjusting motor.
It is a shaft adjusting motor. The pulse motors 27 and 28 connected to the other movable plate 20 are an X-axis adjusting motor and a Y-axis adjusting motor that move the output mirror 22 in the X-axis and Y-axis directions. The rotary shafts 25a, 26a and 27a, 28a of the respective pulse motors are connected to the movable plate 19.20 via screws 25b, 26b and 27b, 28b for coarse mirror tilt adjustment, respectively.
Each movable plate 19.20 is provided with pivots 19a and 20a so that one of the four corners below the figure is a reference point that does not move. As shown in FIG. 4, the high reflection mirror 21 has X
The rotation of the axis adjusting pulse motor 25 causes the pivot 19a to rotate.
The tilt in the horizontal direction (XX) is finely adjusted with the axis as the base axis. Also, by the rotation of the Y-axis adjusting pulse motor 26,
The tilt in the vertical direction (Y-Y) is finely adjusted with the pivot 19a as a base axis. Similarly, as shown in FIG. 5, the output mirror 22 is finely adjusted in the horizontal direction (X-X) about the pivot 20a by the rotation of the X-axis adjusting pulse motor 27. Further, the rotation of the Y-axis adjusting pulse motor 28 causes the pivot 20a to serve as a base axis in the vertical direction (Y-Y).
The tilt of is finely adjusted. In addition, each mirror, by the screws 25b, 26b, and 27b, 28b for coarse adjustment of the mirror tilt described above,
Coarsely adjusted.

Each mirror shows the maximum laser output in a state where each part of the gas laser tube device is thermally stable,
Further, the tilt coarse adjustment screw of each mirror and each pulse motor are adjusted and set so that the emission direction of the output laser beam coincides with the specified direction, which is the reference position. In front of the output mirror, as described above, the two beam splitters 33 and 34 and the light receiving portions 35 and 36 formed of photoelectric conversion elements are respectively attached on their branched optical paths. As shown in the enlarged view of FIG.
Photoelectric conversion elements 35a, 35b, 35c, 35d, and 36a, each consisting of a photodiode, are divided into four regions as divided by the reference horizontal axis X and vertical axis Y of the laser output optical path of the device.
36b, 36c, 36d are arranged in a circle. Thereby, when the laser beam is incident as shown by the dotted line L,
An electric signal corresponding to the intensity distribution and the light receiving area is obtained from each photoelectric conversion element. Therefore, the output level of the output laser light, the direction of the position deviation from the reference origin, and the degree thereof can be calculated and grasped.

Between the support base 14 and the support frame 15 fixed thereon, a pair of movement control elements 48, 49 whose height can be controlled and varied are interposed. These movement control elements 48,49
Can be composed of, for example, a bimetal and a heater wound around the bimetal. Then, the electric power passed through the heater is appropriately supplied from the movement control circuit unit 47 of the laser beam position control unit 43. Thereby, the laser tube 11 and the mirrors 21 and 22 can be moved in parallel with respect to the horizontal plane or can be displaced obliquely by a predetermined angle.

In operation, a part of the output laser light is split by a plurality of beam splitters which are separated by a predetermined distance and is detected by a light receiving portion having a photoelectric conversion element divided into four. The output electric signal of one light receiving portion is transmitted to the control circuit of the power supply portion as a signal indicating the intensity level of the output laser light, that is, the power, and the discharge current is controlled so as to keep the laser light output level stable.
It is used as an information signal for determining the positional deviation of the laser beam from the reference axis by signal comparison and arithmetic processing of the individual photoelectric conversion elements. The output electric signal of the other light receiving portion is used as a signal for determining the positional deviation of the laser beam from the reference axis by the signal comparison and arithmetic processing of the four photoelectric conversion elements. Therefore, when the emission direction of the laser beam coincides with the specified direction, the maximum laser power is incident on the laser output detector 35 and the center of the laser beam coincides with the intersection of the X axis and the Y axis. . When the laser beams L incident on the two light receiving portions deviate from the intersections of the X axis and the Y axis as shown in FIG. 2, the output signal levels of the four photoelectric conversion elements of the respective light receiving portions are accordingly changed. Create balance. Output signals from a total of eight photoelectric conversion elements are converted from analog signals into digital signals by the A / D converter section of the beam position control section and transmitted to the microcomputer section 45.
The input signal is compared with the reference value and arithmetic processing is performed by this microcomputer unit to determine in which direction and how much the laser beam emission direction is parallel or obliquely displaced with respect to the specified reference direction. Outputs a correction signal in the direction. And that signal is the motor power,
And a movement control circuit unit, and a horizontal and vertical adjustment mechanism for each mirror, and a bimetal heater for each movement control element to control the parallel movement or tilt movement of the laser tube discharge path to control the laser beam. The emission direction of is controlled to return to the reference position. In this way, the resonator mirror or the mirror and the optical axis of the laser tube can be moved and controlled automatically so as to have a prescribed laser beam emission direction.

[0014]

As described above, according to the present invention,
Since a plurality of laser beam position detectors are provided at predetermined intervals and the laser beam position signals obtained by these laser beam position detectors are arithmetically processed to drive the mirror tilt adjusting mechanism, It is possible to automatically correct the fluctuation with high accuracy and make it constant.

[Brief description of drawings]

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

FIG. 2 is a side view showing the main part thereof.

FIG. 3 is a top view thereof.

FIG. 4 is a right side view thereof.

FIG. 5 is a left side view thereof.

[Explanation of symbols]

11 ... Gas laser tube, 21 ... High-reflecting mirror, 22 ... Output mirror, 31 ... Laser head section, 37 ... Power supply section, 43 ... Beam position control section, 25, 26, 27, 28 ... Mirror tilt control mechanism, 35.36
… Light receiving part, 48, 49… movement control part.

Claims (2)

[Claims] 1. A high-reflection mirror arranged on one side of a discharge path of a gas laser tube and an output side mirror arranged on the other side, and a mirror tilt adjusting mechanism for adjusting the tilt of at least one of these mirrors. A gas / laser tube device configured to control a mirror tilt adjusting mechanism by detecting a laser light output of the gas / laser tube, the power source device supplying an energizing power to the laser tube; First, a plurality of laser beam position detectors are provided at predetermined intervals, and an electric signal corresponding to the laser beam position obtained by these laser beam position detectors is arithmetically processed to drive the mirror tilt adjusting mechanism, A gas laser tube device, characterized in that it is configured to adjust the tilt of one of the mirrors. 2. A movement control element is provided so as to control the movement of the gas laser tube in parallel or in an oblique direction with respect to the support table, and an electric signal corresponding to the laser beam position obtained by the laser beam position detection section is transmitted. The gas according to claim 1, which is configured to perform arithmetic processing to drive and control the movement control element to control movement of the optical axis of the gas laser tube discharge path.
Laser tube device.