JPS61119086A - Carbon dioxide gas laser oscillator - Google Patents

Abstract

PURPOSE:To obtain the laser oscillator which can emit the beams of the stable mode and output without loss of the laser output by filling a non-discharge part of an optical path of the beams in the oscillator with the gas which does not absorb laser beams. CONSTITUTION:A discharge excitation space 4 is filled with a laser gas including CO2 for laser oscillation and a non-discharge space 6 is filled with the gas which does not absorb the CO2 laser beams. For the gas which does not absorb laser beams, N2, for example, can be used. In the discharge excitation region 4, amplification of the beams is caused by the excited laser gas and the beams reciprocate in the light resonator composed of an output coupling mirror 2 and a high reflection mirror 3 to effect laser oscillation. In the discharge region 4, the beams are amplified. Because the non-discharge region 6 is filled with the gas which does not absorb laser beams at all, there is no loss of laser output and no partly high temperature part, i.e., no partial change of flexibility index so that the laser beams of the stable mode and output can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an oscillator configuration for improving oscillation efficiency and mode in a COt laser oscillator according to the present invention.

[Conventional technology]

FIG. 3 is a sectional view showing a conventional laser oscillator. (1
(2) is a laser oscillator, (2) is an output coupling field, and (3) is a high-reflection mirror.These two mirrors constitute an optical resonator, and the CO! The laser gas containing . , (2), the laser beam (5) is emitted from the root generator (5).

When laser oscillation occurs, in the beam optical path, light is amplified in the discharge excitation region (4), but the laser gas absorbs the light in the non-discharge excitation region (3).

In particular, as the temperature of the laser gas in the non-excited part increases, the absorption of laser light, that is, the attenuation of the laser power becomes more severe, leading to a decrease in the output of the laser oscillator.

Furthermore, the gas that has absorbed the laser light instantaneously reaches a high temperature, causing a local density change, which causes instability in the mode and output of the laser emitted beam.

[Problem that the invention seeks to solve]

Since conventional laser oscillators are configured as described above, it is rarely necessary to cool the gas in the non-discharge area or to constantly circulate the gas so that the gas in the non-discharge area does not become hot. . Also, even if the gas is cooled or circulated to reduce mode fluctuations or output instability,
A frequent problem was that it was impossible to prevent the output laser power from decreasing due to absorption of laser gas.

This invention has been developed to eliminate the above-mentioned problems, and an object of the present invention is to provide a device in which absorption of laser light by gas in a non-discharge area does not occur.

[Means for solving problems]

In the laser oscillator according to the present invention, the gas in the beam optical path of the non-discharge part is not a laser gas containing COl, but Co, L/
- This is a replacement for the beam and a gas that does not absorb it at all.

[For production]

CO, a gas that does not absorb the laser beam at all, does not cause a decrease in laser output and does not cause a temperature increase due to absorption, so it does not cause instability in the mode or output.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

In Figure 1, (υ is CO with an average output of 300 W or more,
Laser oscillator, (2) semi-transparent output coupling mirror, (3)
is a high-reflection mirror, (4) is a discharge excitation part formed by a discharge between a pair of electrodes (not shown), (3) is a non-discharge excitation part, and (7) is a discharge excitation part and a non-discharge excitation part. There is a transparent window to separate the parts. The discharge excitation space (4) is filled with a laser gas containing CO1 for laser oscillation. (3) The non-discharge space is CO! It is filled with a gas that does not absorb laser light. Examples of gases that do not absorb laser light include N! can be used.

Light is amplified by the laser gas excited in the discharge excitation region (4), and the light travels back and forth within the optical resonator formed by the output coupling mirror (2) and the high reflection mirror (3).
Saw+1' oscillates. At that time, the light is amplified in the discharge region, and the non-discharge region is completely filled with gas that does not absorb laser light, so there is no loss of laser output, and there is no loss of laser output in the non-discharge region. Since there is no significant change in refractive index, a laser beam with stable mode output can be obtained.

In the above embodiments, a laser oscillator without folding is described, but a laser oscillator which folds back into the laser beam optical path may be used.

An example is shown in FIG. In FIG. 2, a discharge excitation region (4) and a non-excitation region (3) separated by a transmission mirror (7) are filled with laser gas, COt laser light, and gas that does not absorb, respectively.

〔Effect of the invention〕

As described above, according to the present invention, the non-discharge portion of the beam optical path within the oscillator is filled with a gas that does not absorb laser light, so that a beam with stable mode and output can be emitted without loss of laser output. This has the effect of providing a laser oscillator that can perform

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a laser oscillator according to an embodiment of the present invention, FIG. 2 is a sectional view of a laser oscillator according to another embodiment of the invention, and FIG. 3 is a sectional view showing a conventional laser oscillator. It is. In the figure, (1) is the laser oscillator, (2) is the output coupling mirror, (3) is the high reflection mirror, (4) is the discharge excitation region, and (5) is the output coupling mirror.
is a laser emission beam, (3) is a non-excitation region, (7) is a transmission window, and (8) is a folding mirror. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (3)

[Claims] (1) In a CO_2 laser oscillator with an average output of 300 W or more and having at least two reflecting mirrors and at least one discharge excitation region, the discharge excitation region and the non-excitation region are separated by at least one transmission window in the beam optical path of the laser oscillator. A CO_2 laser oscillator characterized in that the beam path of the non-excited region is filled with a gas that does not absorb laser light. (2) The laser oscillator according to claim 1, wherein N_2 is used as the gas that does not absorb laser light. (3) The laser oscillator according to claim 2, wherein the intra-cavity beam optical path is folded.