JPH06314830A - Adjusting device for laser beam - Google Patents

Abstract

PURPOSE:To provide a beam adjusting device of a laser which can realize operational efficiency and safety by enabling accurate optical axis and beam adjustment in a laser by a simple constitution and can improve processing accuracy and processing speed of laser beam by adjusting laser beam during laser oscillation. CONSTITUTION:This device, wherein beam intensity and other physical quantity of a laser are measured and fed back to a laser oscillation means, has a beam intensity measurement means 3 for measuring beam intensity of oscillated laser light, a control means 4 for outputting a control signal based on a beam intensity detection signal from the beam intensity measurement means 3 and an adjustment driving means 5 for adjusting an optical axis of a laser oscillation means 2 by a control signal from the control means 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser beam adjusting device, and more particularly to a laser beam adjusting device capable of adjusting the beam intensity of a laser such as an excimer laser.

[0002]

2. Description of the Related Art Conventionally, for example, in order to oscillate an excimer laser with high efficiency, accurate optical axis adjustment is essential.

In the first conventional method for adjusting the optical axis, the position of the reflecting mirror in the optical resonator is roughly adjusted by using a helium neon laser or the like.

In the second method, laser light emitted from a backing paper called burn paper is irradiated, and the beam shape and the beam intensity are confirmed by the unevenness of the burn paper.

In the third method, while monitoring a beam intensity measuring device such as an energy meter, the tilt of the reflecting mirror in the optical resonator is manually adjusted to fix the reflecting mirror at a position where the laser output is maximized. .

In such a conventional adjustment method, since the beam intensity is repeatedly measured and confirmed visually,
There is a problem that the quality becomes unstable as a result of the adjustment taking time and the accuracy of the adjustment depending on the skill of the adjuster.

For example, in the excimer laser, the optical axis is adjusted by manually operating the optical axis adjusting device supporting the semi-reflecting mirror located on the front surface side.

Normally, in an excimer laser, its output is compensated by gradually increasing the applied voltage as the output decreases, or by additionally injecting a rare gas that decreases as the laser is emitted.

Further, during various kinds of processing using a laser such as an excimer laser, the processing accuracy may be lowered due to a change in output of a laser beam during processing, a change in beam shape, or the like.

In such a case, the control usually performed during the laser oscillation is the output compensation accompanied with the decrease of the average output of the laser as described above, and this control is to increase the voltage applied to the laser excitation circuit. However, there is a problem in that it is impossible to automatically adjust depending on the above-mentioned fluctuation state.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it makes it possible to accurately perform an optical axis or beam adjustment in a laser with a simple structure to improve work efficiency and work efficiency. It is an object of the present invention to provide a laser beam adjusting device which can improve the processing accuracy and the processing speed of a laser beam by adjusting the laser beam during laser oscillation for safety.

[0012]

That is, the present invention focuses on measuring the beam intensity and other physical quantities of the laser and feeding it back to the laser oscillating means. A beam adjusting device for a laser for adjusting the beam intensity of the oscillated laser beam, and a control means for outputting a control signal based on a beam intensity detection signal from the beam intensity measuring means. And a laser beam adjusting device for adjusting the optical axis of the laser oscillating means by the control signal from the controlling means.

The adjustment drive means can adjust a reflection mirror such as a total reflection mirror or a semi-reflection mirror of the laser oscillation means.

A second invention is a laser beam adjusting device for properly adjusting a beam of laser light for processing a material to be processed, which is a processing position on a processing surface of the material to be processed by the oscillated laser light. Deviation, surface temperature, beam intensity, and other physical quantities for measuring physical quantities, control means for outputting a control signal based on the physical quantity detection signal from this machining area, and control signals from this control means A beam adjusting apparatus for a laser, comprising: an adjusting driving means for adjusting a laser oscillating means.

The adjustment drive means can adjust at least one of the optical system drive means of the laser oscillation means and the laser excitation voltage control means.

A third aspect of the invention is a laser beam adjusting device for properly adjusting the beam of laser light,
Measuring means for measuring at least one of the beam intensity of the oscillated laser light and the physical quantity on the processed surface of the material to be processed by the oscillated laser light, and the control signal is output based on the detection signal from this measuring means. The laser beam adjusting device is characterized by comprising: a control means for controlling the laser oscillation means and an adjusting driving means for adjusting the laser oscillation means by the control signal from the control means.

[0017]

In the laser beam adjusting device according to the first invention, the intensity of the oscillated laser beam is measured, and the optical axis of the laser oscillating means is adjusted by the control signal according to the beam intensity detection signal. Therefore, the optical axis of the laser can be automatically adjusted and the laser oscillation can be stabilized.

Further, in the laser beam adjusting apparatus according to the second aspect of the invention, the laser beam intensity and other physical quantities on the processed surface are measured and fed back, so that the laser beam is stabilized and the processing accuracy is improved. And the processing speed can be improved.

Further, in the laser beam adjusting apparatus according to the third aspect of the invention, at least one of the beam intensity and the physical quantity on the processing surface is measured and fed back, so that the stage of laser oscillation and the processing can be improved. In both stages, the laser beam can be stabilized and the processing accuracy and processing speed can be improved.

[0020]

EXAMPLE Next, taking an excimer laser as an example,
A laser beam adjusting apparatus 1 according to a first embodiment of the present invention will be described with reference to FIG.

FIG. 1 is a schematic explanatory view of the laser beam adjusting apparatus 1, in which the laser beam adjusting apparatus 1 is
It has a beam intensity measuring means 3 for measuring the laser light from the laser oscillating means 2, a control means 4, and a reflecting mirror driving means 5 as an adjusting driving means.

The laser oscillating means 2 comprises a laser container 6
And a laser optical resonator 9 having a total reflection mirror 7 and a semi-reflection mirror 8 to oscillate a laser beam having a predetermined intensity.

The beam intensity measuring means 3 measures the beam intensity of the laser light, and it is possible to use, for example, a light receiving element such as a photodiode or an energy meter.

The control means 4 calculates the beam intensity detection signal from the beam intensity measuring means 3 and outputs a control signal to control and drive the reflecting mirror driving means 5.

The reflecting mirror driving means 5 drives an optical axis adjusting device (not shown) of the semi-reflecting mirror 8 or is provided in place of this optical axis adjusting device. The beam intensity is adjusted to a desired level.

In the laser beam adjusting apparatus 1 having such a configuration, the beam intensity of the laser light from the laser oscillating means 2 is measured by the beam intensity measuring means 3.

The obtained beam intensity data is calculated in the control means 4 to determine the driving direction and driving amount of the semi-reflecting mirror 8.

A drive control signal is transmitted from the control means 4 to the reflecting mirror driving means 5, and the reflecting mirror driving means 5 adjusts the position or the posture of the supported semi-reflecting mirror 8.

By appropriately repeating these operations,
The optical axis of the laser can be adjusted.

The optical axis of the laser can be regarded as optimum when the beam intensity has the maximum value, but it is not always necessary to match the maximum value.

Next, taking an excimer laser as an example, a laser beam adjusting device 10 according to a second embodiment of the present invention will be described with reference to FIG. However,
The same reference numerals are given to the same portions as, and the detailed description thereof will be omitted.

FIG. 2 shows a beam adjusting device 10 for this laser.
FIG. 3 is a schematic explanatory view of the guide optical system 11 for guiding the laser light from the laser oscillation means 2 to the material M to be processed.
Is provided.

This guiding optical system 11 includes a first reflecting mirror 12
And a second reflecting mirror 13, a mask 14, a half mirror 15, and a condenser lens 16.

The laser beam adjusting device 10 includes a machined surface measuring means 17, a control means 18, and an optical system driving means 19.
And the adjustment drive means 21 including the laser excitation voltage control means 20.

The laser oscillating means 2 and the laser beam adjusting device 10 as a whole are mounted on a vibration isolation table 22.

The mask 14 assists the measurement by the machined surface measuring means 17, and is not always necessary, and the machined surface measuring means 17 may directly perform the measurement.

The machined surface measuring means 17 measures the processing state of the material M to be processed, and employs one capable of measuring various physical quantities.

The various physical quantities to be measured include, for example, the deviation of the processing position in the material M to be processed or the state of the material M to be processed such as the surface temperature or temperature distribution, the diameter of the laser beam, and the size of the particles scattered by the processing. Alternatively, there is the speed, the beam intensity of the laser light reflected on the surface of the material M to be processed, or the like.

The control means 18 calculates the data measured by the machined surface measuring means 17 and sends a necessary control signal to the adjustment drive means 21 (optical system drive means 19 and laser excitation voltage control means 20).

The optical system driving means 19 is a driving device for moving and adjusting the optical system including the laser optical resonator 9, and by moving the optical system, the laser optical axis can be adjusted to correct the unevenness of the laser beam intensity. It is a thing.

The laser excitation voltage control means 20 is a circuit for controlling the laser excitation voltage, and it is possible to control the laser output by changing the excitation voltage.

In the laser beam adjusting apparatus 10 having such a structure, the laser light oscillated from the laser oscillating means 2 passes through the guide optical system 11 and is irradiated on the material M to be processed, and the surface of the material M to be processed is ablated or the like. Is processed.

The processed surface measuring means 17 measures the progress of the processing simultaneously with the processing, or the state of reflection of laser light on the processed surface.

The data obtained by the machined surface measuring means 17 is calculated by the control means 18, and the necessity of control, the control method, the control amount, etc. are determined.

A drive control signal is transmitted from the control means 18 to the optical system drive means 19 and the laser excitation voltage control means 20 to adjust the optical axis of the laser or the laser output.

By repeating such control, the laser beam during processing is stabilized and the processing accuracy is improved.

Further, the processing speed can be improved by increasing the laser output within the range where the processing quality is not deteriorated.

The present invention is based on the above-mentioned laser beam adjusting apparatus 1 (FIG. 1) and laser beam adjusting apparatus 10.
By combining (FIG. 2), the laser beam can be adjusted both in the adjustment stage of laser oscillation and the processing stage by the oscillated laser, so that the laser operation can be totally stabilized and efficient.

Furthermore, the present invention can be applied to lasers other than excimer lasers, and can also be used as a laser output stabilizing mechanism by executing control during laser oscillation.

[0050]

As described above, according to the present invention, since the oscillated laser beam is measured and fed back, the laser oscillation work is made safe and efficient, and at the time of processing work. It is also possible to improve processing accuracy and processing speed.

[0051]

[Brief description of drawings]

FIG. 1 is a schematic explanatory diagram of a laser beam adjusting apparatus 1 according to a first embodiment of the present invention.

FIG. 2 is a schematic explanatory diagram of a laser beam adjusting apparatus 10 according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Laser Beam Adjusting Device 2 Laser Oscillating Means 3 Beam Intensity Measuring Means 4 Controlling Means 5 Reflecting Mirror Driving Means (Adjusting Driving Means) 6 Laser Container 7 Total Reflecting Mirror 8 Semi-Reflecting Mirror 9 Laser Optical Resonator 10 Laser Beam Adjusting Means 11 Guide Optical System 12 First Reflecting Mirror 13 Second Reflecting Mirror 14 Mask 15 Half Mirror 16 Condensing Lens 17 Machining Surface Measuring Means 18 Controlling Means 19 Optical System Driving Means (Adjusting Driving Means) 20 Laser Excitation Voltage Controlling Means ( Adjustment drive means) 21 Adjustment drive means 22 Vibration isolation table M Work material

Claims (5)

[Claims] 1. A laser beam adjusting device for properly adjusting a beam of laser light, comprising beam intensity measuring means for measuring the beam intensity of oscillated laser light, and beam intensity detection from the beam intensity measuring means. A laser beam adjusting apparatus comprising: a control unit that outputs a control signal based on a signal; and an adjustment drive unit that adjusts the optical axis of the laser oscillation unit based on the control signal from the control unit. 2. The laser beam adjusting apparatus according to claim 1, wherein the adjusting driving means adjusts a reflecting mirror of the laser oscillating means. 3. A laser beam adjusting device for appropriately adjusting a beam of a laser beam for processing a material to be processed, comprising: a machined surface measurement for measuring a physical quantity on a machined surface of the material to be processed by an oscillated laser beam. Means, a control means for outputting a control signal based on the physical quantity detection signal from the machined surface measuring means, and an adjustment drive means for adjusting the laser oscillation means by the control signal from the control means. Laser beam conditioner to do. 4. The laser beam adjusting apparatus according to claim 3, wherein the adjustment drive means adjusts at least one of an optical system drive means and a laser excitation voltage control means of the laser oscillation means. 5. A laser beam adjusting device for appropriately adjusting a beam of laser light, comprising at least one of a beam intensity of oscillated laser light and a physical quantity on a processing surface of a material to be processed by the oscillated laser light. A measuring means for measuring one of them, a controlling means for outputting a control signal based on a detection signal from the measuring means, and an adjusting driving means for adjusting the laser oscillation means by the control signal from the controlling means. A laser beam adjusting device characterized by the above.