JPH0322578A - gas laser oscillation device - Google Patents

Abstract

PURPOSE:To enable a gas laser of this design to output a laser beam stably for a long period by a method wherein a metal electrode is formed of sintered alloy of copper, nickel, and tungsten, and the surface of the electrode is subjected to a chrome diffusion treatment. CONSTITUTION:Tungsten particles are wrapped up in nickel and chrome is diffused to them. Tungsten particles are restrained from being oxidized by wrapping them up in nickel. Copper and nickel can be protected against oxidation by the diffusion of chrome. As the surface of a metal electrode is subjected to a chrome diffusion treatment, the surface of the electrode is hardened and hardly sputtered. Therefore, even if a discharge is kept going for a long time, the surface of the metal electrode is hardly deteriorated and the electrode keeps a discharge very stably.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a Gannulas laser oscillation device in which the axial direction of a discharge tube and the optical axis direction are aligned, and in particular to a gas laser oscillation device that can obtain the most stable laser beam. It is related to.

2. Description of the Related Art A conventional gas laser oscillation device is shown in FIG. 2a. In this figure, 1 is a discharge tube made of a dielectric material such as galanium, and 2 and 3 are metal electrodes provided inside the discharge tube 1. 4 is a high voltage power supply connected to the electrodes 2, 3, for example, soKV voltage is applied to both the electrodes 2, 3.
It is applied for 3 hours. Reference numeral 5 denotes a discharge space within the discharge tube 1 which is sandwiched between the electrodes 2 and 3. 6 is a total reflection mirror, and 7 is a partial reflection mirror.The total reflection mirror 6 and the partial reflection mirror 7 are fixedly arranged at both ends of the discharge space 6, and form an optical resonator. Reference numeral 8 denotes a laser beam outputted from the partial reflecting mirror 7. Arrow 9 indicates the direction in which the laser gas flows and circulates within the axial flow laser device. 10 is an air pipe, 11.12 is a heat exchanger for lowering the temperature of the laser gas whose temperature has risen due to the discharge and blower in the discharge space 6, and 13 is a gas supply for circulating the laser gas. \-7 It's a wind machine.

Approximately 100 m/s in the discharge section 5 due to the blower 13
It is necessary to obtain a gas flow of about eC.

The above is the configuration of the conventional axial flow type laser device, and its operation will be explained next.

First, a high voltage is applied from a high voltage power source 4 to the pair of metal electrodes 2 and 3 to generate a glow-like discharge in the discharge space 5. The laser gas passing through the discharge space 5 is excited by obtaining this discharge energy, and the excited laser gas enters a resonant state in an optical resonator formed by a total reflection mirror 6 button and a partial reflection mirror 7. , a laser beam 8 is output from the partially reflecting mirror 7. This laser beam 8 is used for purposes such as laser processing. FIG. 2b is a detailed view of the surface of the metal electrode section.

As a material for the metal electrode 2, a sintered alloy such as tungsten and copper is used. The reason for using this sintered alloy is that the discharge is uniformly and selectively dispersed due to the difference in the thickness of the tungsten and copper oxide films, so even when the discharge energy is increased, the discharge does not shift to an arc and is stable. This is because glow discharge can be obtained.

Problems to be Solved by the Invention In the above structure, if the electrode 2 is used for a long time, the tungsten oxide will grow and accumulate, covering the copper surface and making it difficult to discharge. There was a problem in that stable glow discharge could not be obtained due to scattering and contaminating the inside of the discharge tube.

The present invention was made to solve this problem, and an object of the present invention is to provide a gas laser oscillation device that can obtain a stable laser beam by uniformly spreading glow discharge within a discharge tube over a long period of time.

Means for Solving the Problems In order to solve the above problems, the present invention provides a Gannu laser oscillation device in which the metal electrodes in the discharge tube are made of a sintered alloy made from copper, nickel, and tungsten, and chromium is diffused on the surface of the metal electrodes. That is.

Function: The metal electrode used in the present invention allows a uniform glow discharge to be obtained over a long period of time, making it possible to produce a stable laser beam.

Embodiment FIG. 1a is a detailed view of the surface of a metal electrode according to an embodiment of the present invention. Tungsten particles are wrapped in nickel and diffused with chromium. Second, by wrapping the tungsten particles in Nokel, the progress of oxidation of the tungsten particles is suppressed. Furthermore, by diffusing chromium, oxidation of copper buttons and nickel can also be suppressed. Furthermore, the chromium diffusion treatment hardens the metal electrode surface, making it less likely to be sputtered. Therefore, even if the discharge continues for a long time, the surface of the metal electrode hardly deteriorates and the discharge is extremely stable.

FIG. 1b shows the long-term stability of the laser output due to the difference between the conventional example and the embodiment of the present invention. As is clear from this figure, in the embodiment of the present invention, if the depth of chromium diffusion is set to 5 microns or more, no reduction in output is observed over a long period of time.

Effects of the Invention As described above, according to the present invention, the metal electrode is made of a sintered alloy of copper, nitrogen, and tungsten, and the metal surface is subjected to chromium diffusion treatment, so that there is no deterioration of the metal electrode over a long period of time. It is possible to provide a gas laser oscillation device that emits a highly stable laser beam, which has an excellent effect on improving reliability.

[Brief explanation of drawings]

FIG. 1a is a schematic cross-sectional view showing the electrode surface of a Gunnery laser oscillation device showing an embodiment of the present invention, FIG. 1b is a time characteristic diagram of the laser output of the same gas laser oscillation device and a conventional example,
Figure a is a circuit diagram of a typical gas laser oscillation device, Figure 2 b
FIG. 2 is a schematic cross-sectional view showing the surface of a conventional electrode.

Claims (2)

[Claims] (1) Laser gas is caused to flow through a discharge tube made of an insulator in the optical axis direction using a blower, a high voltage is applied between metal electrodes provided at both ends of the discharge tube, and a discharge is generated within the discharge tube. In a gas laser oscillation device that emits a laser beam in the axial direction of the discharge tube as a laser excitation source, the metal electrode is a sintered alloy made of copper, nickel, and tungsten, and the surface of the metal electrode is treated with diffusion treatment of chromium. A gas laser oscillation device characterized by: (2) The gas laser oscillation device according to claim 1, wherein the diffusion depth from the surface of the metal electrode in the chromium diffusion treatment is 5 microns or more.