JPH1027932A - Gas laser oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the adhesion of impurities to a mirror surface by a method wherein bag-like recessions for collecting the back flow of partial turning flow of vapor laser medium to a laser tube are provided on a laser medium diffusing slit main bodies. SOLUTION: Laser medium diffusing slit main bodies 10a are provided between a laser tube 6 and photoamplifying mirrors 4, 5 so as to provide bag-like recessions A for collecting the impurities of partial vapor laser medium back flowing into the turning flow to the laser tube 6. In such a constitution, the partial fuming flow in the inverse direction to the laser tube 6 side of the vapor laser medium containing impurities such as oil mist, etc., runs into the bag-like recessions A along the slit body wall surface for collecting the impurities. Through these procedures, the decline in the reflecting power on a mirror surface due to the adherence of the impurities as well as the sputter-like seizure can be avoided thereby enabling the stable laser beams to be emitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a laser tube of a laser resonator which circulates a gas laser medium, excites discharge, and generates a laser beam optically amplified by an optical amplifying mirror. And a gas laser oscillation device.

[0002]

2. Description of the Related Art FIG.
It is explained along. In FIG. 3, 1 is a gas laser medium circulating in the laser oscillation device, 2 is a DC high-voltage power supply for generating discharge, and 3a and 3b are the DC high-voltage power supply 2
4 is a partially transmitting reflection mirror (mirror for light amplification) for amplifying light and taking out a laser beam; 5 is a total reflection mirror (mirror for light amplification) for amplifying light;
Is a laser tube, 7 is a blower for circulating the gas laser medium 1,
Reference numeral 8 denotes a laser medium cooler, 9a and 9b denote laser medium piping lines, and 10 denotes a laser medium diffusion slit main body provided between the laser tube 6 and the optical amplification mirrors 4 and 5.

[0003] Regarding the above conventional gas laser oscillation device,
The relationship and operation of each component will be described. Optical amplification mirrors 4 and 5 are respectively attached to both ends of a laser tube 6 of the laser resonator via a slit body for laser medium diffusion, and a blower 7 and a laser are attached to the laser tube 6 using laser medium piping systems 9a and 9b. The gas laser oscillation device was configured by connecting the medium coolers 8 sequentially. With the above configuration, the gas laser medium 1 circulates through the laser tube 6 and is supplied by the DC high-voltage power supply 2 via the discharge electrodes 3a and 3b.
Is applied with a high voltage, and a glow discharge occurs. Further, the gas laser medium 1 is forcibly circulated by the blower 7 and is sent into the glow discharge space through the laser medium piping system passage 9a. The gas laser medium 1 heated by the glow discharge is cooled by the laser medium cooler 8 through the laser medium piping path 9b, and then circulates back to the blower 7.

The gas laser medium 1 is excited by glow discharge generated between the discharge electrodes 3a and 3b, and a laser beam output by laser oscillation is amplified while reciprocating between the optical amplification mirrors 4 and 5. Is done.

At this time, in order to obtain high laser oscillation efficiency, it is necessary to make the distribution of discharge uniform in the glow discharge region. The distribution of this discharge depends on the flow of the gas laser medium 1. In order to make the discharge uniform, it is necessary to prevent the gas laser medium 1 from flowing intensively at one place. In order to diffuse the flow of the gas laser medium 1 to a non-discharge portion upstream of the region and generate a swirl flow, the slit main body 10 for laser medium diffusion is used.

[0006]

In the conventional gas laser oscillating device having the above-mentioned structure, most of the swirling flow of the gas laser medium 1 generated by the slit body 10 for diffusing the laser medium flows in the direction of the laser tube 6. Due to the action of the complicated fluid inside the slit body, there was a small swirling flow of the gas laser medium 1 in which a part of the fluid flows in the direction opposite to the laser tube 6 direction.

Further, the gas laser medium 1 circulating through the laser oscillation device contains impurities such as oil mist generated from the gear portion of the blower 7 and dust mixed from outside the gas laser medium circulation system. The swirling flow containing these impurities flows in the opposite direction of the laser tube 6 along the wall surface of the slit body 10 for diffusing the laser medium, so that the swirling flow is directed to the surfaces of the optical amplification mirrors 4 and 5 provided in that direction. , A phenomenon that the impurities adhere to the mirror surface has occurred.

These impurities have a lower reflectivity than the material constituting the optical amplification mirrors 4 and 5, and when the impurities adhere to the surfaces of the optical amplification mirrors 4 and 5 for the above-mentioned reason, the impurities absorb the laser beam. Therefore, the reflectivity of the optical amplification mirrors 4 and 5 decreases, so that the laser oscillation efficiency deteriorates and the laser output decreases.

Further, there is a problem that impurities adhering to the surfaces of the optical amplification mirrors 4 and 5 absorb the laser beam and become high temperature to cause spatter-like baking and eventually damage the optical amplification mirrors 4 and 5 themselves. He also had points.

[0010]

According to a first aspect of the present invention, there is provided a laser medium diffusing slit body between a laser tube of a laser resonator and an optical amplification mirror. A gas laser oscillation device having a bag-shaped concave portion for collecting a part of the swirling flow of a gas laser medium flowing backward from a slit main body for laser medium diffusion into a laser tube.

Further, a second means of the present invention is a gas laser oscillating device having a slit body for diffusing a laser medium between a laser tube of a laser resonator and a mirror for amplifying a laser medium. The slit main body is provided with a through hole through which the gas laser medium flows so as to offset a part of the swirling flow of the gas laser medium flowing into the laser tube.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the configuration of the first means of the present invention described above, a part of a swirling flow containing impurities such as oil mist and dust in a laser medium causes a partial reverse flow toward a light amplification mirror. Even if it flows, it flows into the bag-shaped recess provided in the slit body for laser medium diffusion. The bag-shaped recess collects impurities in the laser medium and acts so as not to adhere to the surface of the optical amplification mirror.

Further, according to the configuration of the second means of the present invention,
The swirling flow of the laser medium flowing from the laser medium diffusion slit body tends to flow into the laser tube, but the laser medium also flows from the through hole provided in the slit body so as to offset some of the backflow. , And acts to prevent impurities in the laser medium from reaching the optical amplification mirror.

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIG. In FIG. 1, reference numerals 1 to 9a and 9b are the same as those in FIG. 3 showing a conventional gas laser oscillation device, and therefore description thereof is omitted.

Reference numeral 10a denotes a laser medium diffusion slit body provided between the laser tube 6 of the laser resonator and the optical amplification mirrors 4 and 5, and the laser medium diffusion slit body 10a
Has a slit-shaped recess provided in the slit body for collecting impurities of a part of the gas laser medium 1 flowing backward against the swirling flow flowing into the laser tube 6.

With this configuration, of the swirling flow of the gas laser medium 1 containing impurities such as oil mist, the flow in the direction opposite to the laser tube 6 side is directed along the slit main body wall surface.
It flows into the bag-shaped concave portion a. Impurities are collected in the bag-shaped concave portion a, the impurities of the optical amplification mirrors 4 and 5 do not reach, and a sputter-like seizure does not occur on the mirror surface, and a stable laser output can be obtained. Things.

(Embodiment 2) Next, Embodiment 2 of the present invention will be described with reference to FIG.

In FIG. 2, reference numerals 1 to 9a and 9b are the same as those in FIG. 3 showing a conventional gas laser oscillation device, and therefore the description thereof is omitted. 10b is a slit body 10b for diffusing the laser medium provided between the laser tube 6 of the laser resonator and the mirrors 4 and 5 for amplifying the light. The swirling flow of the gas laser medium 1 flowing into the slit body 10b for diffusing the laser medium is provided. Some of the gas laser medium is changed by the mirrors 4 and 5 for optical amplification.
A through-hole is provided so that the gas laser medium 1 flows in from around the upstream side of the slit main body so as to cancel backflow to the side.

The through hole B is formed so that the gas laser medium 1 flows at an angle opposite to the angle of the slit body 10b. As a result, of the swirling flow of the gas laser medium 1, the flow in the direction opposite to the laser tube 6 is canceled by the flow from the through-hole b, so that the swirling flow reaches the optical amplification mirrors 4 and 5. And the impurities in the gas laser medium can be prevented from adhering to the mirror surface.

[0020]

As described above, the first means of the present invention comprises a slit body for diffusing a laser medium between a laser tube of a laser resonator and a mirror for optical amplification. By providing a bag-shaped concave portion for collecting a partial backflow of the swirling flow of the gas laser medium, the swirling flow of the gas laser medium containing impurities flows into the concave portion and cannot reach the laser oscillation mirror. In addition, it is possible to prevent the reflectivity of the mirror surface from being lowered due to the adhesion of impurities and to prevent spatter-like seizure, thereby achieving an excellent effect of obtaining a stable laser beam.

According to a second aspect of the present invention, a slit body for diffusing a laser medium is provided between a laser tube of a laser resonator and a mirror for optical amplification, and the slit body for diffusing a laser medium is provided with a gas laser medium. A through-hole for inflow of the gas laser medium so as to offset a part of the backflow of the swirling flow toward the laser tube side is provided, and the swirling flow of the gas laser medium containing impurities flows into the laser tube side, It cannot reach the mirror for optical amplification, prevents the reflectivity of the mirror from lowering due to the attachment of impurities and prevents spatter-like seizure, and has an excellent effect of obtaining a stable laser beam. is there.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a gas laser oscillation device according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a gas laser oscillation device according to the second embodiment.

FIG. 3 is a schematic configuration diagram of a conventional gas laser oscillation device.

[Explanation of symbols]

 10a, 10b Slit body for laser medium diffusion a. Bag-shaped recess b. Through hole

Claims (2)

[Claims] A slit body for laser medium diffusion is provided between a laser tube of a laser oscillator for generating a laser beam optically amplified by a mirror for optical amplification and a mirror for optical amplification. What is claimed is: 1. A gas laser oscillating device comprising: a slit main body for diffusing a gas laser medium into a laser tube; 2. A slit body for diffusing a laser medium between a laser tube of a laser resonator for generating a laser beam optically amplified by a mirror for optical amplification and a mirror for optical amplification. A gas laser oscillation device comprising: the laser medium diffusion slit body,
A gas laser oscillation device provided with a through-hole through which a gas laser medium flows so as to cancel a part of a backflow of a swirling flow to a laser tube.