JPH03266484A - Gas laser oscillator - Google Patents

Abstract

PURPOSE:To enable a cathode to be easily held and to dispense with a specific alignment process of a laser beam by a method wherein an electrode support pin is provided to a laser discharge tube in one piece penetrating through the tube wall of a laser discharge tube, and a cathode electrode is fixed in ring inside the laser discharge tube by the electrode support pin. CONSTITUTION:Anode electrode holders 11 and 15 provided with laser gas inlets 13 and 17 are provided adjacent to the outer ends of laser discharge tubes 3 and 5 respectively, and pin-like anode electrodes 21 and 23 are provided to them respectively. Tungsten electrode support pins 25 sand 27 are provided to the laser discharge tubes 3 and 5 at a halfway point in an axial direction respectively through a insert molding method, made to extend penetrating through the side walls of the laser discharge tubes 3 and 5, and fix and support ring-shaped cathode electrodes 29 and 31 at the tips inside the laser discharge tubes respectively. By this setup, the laser discharge tubes 3 and 5 are not required to be divided into two glass tubes, component parts are decreased in number, and an alignment process can be dispensed with.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a gas laser oscillator, and particularly to a discharge excitation type axial flow gas laser oscillator.

(Prior art) As a gas laser oscillator that uses gas such as CO□ gas as a laser medium, the laser gas is excited by discharge between an anode electrode and a cathode electrode that are spaced apart from each other in the axial direction of a glass-controlled laser discharge tube. Discharge-pumped axial flow gas laser oscillators configured to perform this purpose are well known.

In the above-mentioned axial flow gas laser oscillator, in order to obtain a large laser output, two laser discharge tubes are connected in series with a center block that also serves as a laser gas outlet.
A laser gas inlet and an anode electrode are provided at the ends of the two laser discharge tubes opposite to the mutual connection ends, and a cathode electrode is provided at the connection ends of each of the two laser discharge tubes. There is a dual type device configured so that discharge occurs between an electrode and a cathode electrode.

In a double-barrel type axial flow gas laser oscillator, the cathode electrodes of two laser discharge tubes connected in series are arranged adjacent to each other with a center block in between, so that the anode electrode and cathode electrode of each laser discharge tube In order to ensure a reliable discharge between the two cathode electrodes, it is necessary to widen the distance between the two cathode electrodes to a predetermined value or more. There is.

In this case, the problem is how to support the cathode electrode. Conventionally, one laser discharge tube is divided into two glass tubes, and these two glass tubes are connected by a metal connection made of aluminum or the like. The connection is made by a member and a cathode electrode is attached to this connecting member.

(Problems to be Solved by the Invention) In the cathode electrode support structure as described above, not only the number of component parts is large, but also the accuracy of the connection between the two glass tubes,
In other words, it is necessary to maintain concentricity with high precision, and for this reason, laser beam alignment is required for each laser discharge tube.
Moreover, replacing the laser discharge tube becomes troublesome.

In view of the above-mentioned problems, the present invention aims to provide a gas laser oscillator that has a simple structure, properly holds a cathode electrode, and does not require special laser beam alignment in one laser discharge tube. The purpose is

[Structure of the Invention] (Means for Solving the Problems) According to the present invention, the above-mentioned object is to provide a gas laser oscillator in which a cathode electrode is provided midway in the axial direction of a glass laser discharge tube. A tungsten electrode support pin extending through the tube wall of the laser discharge tube is integrally provided, and a ring-shaped cathode electrode is fixedly arranged within the laser discharge tube by the electrode support pin. This is achieved by a gas laser oscillator characterized by the following.

(Function) According to the above-described configuration, one laser discharge tube is made up of one glass tube, thereby eliminating the need for alignment in one laser discharge tube.

The cathode electrode is sealed and fixed in the laser discharge tube by an electrode support pin that is integrally provided with the laser discharge tube. Since it is made of tungsten which has a coefficient of thermal expansion, no thermal stress is applied to the integral connection portion between the two due to the difference in the coefficient of thermal expansion between the two.

(Example) Embodiments of the present invention will be described in detail below with reference to the drawings.

1 and 2 show one embodiment of a gas laser oscillator according to the present invention. A gas laser oscillator includes two laser discharge tubes 3 and 5 connected in series to each other by a center block 1 made of metal such as aluminum.
have. The laser discharge tubes 3 and 5 are each made of heat-resistant glass such as borosilicate glass (Pyrex), and reflector mirrors 7 and 9 as optical resonators are provided at the outer ends of each. Either one of the reflecting mirrors 7 and 9 is constructed as a so-called half mirror and serves as an output mirror.

A laser gas population 13 is provided near the outer ends of each of the laser discharge tubes 3 and 5, that is, at the ends opposite to the mutual connection ends.
An anode electrode holder 11.15 with 17 is provided. Laser discharge tubes 3 and 5 are installed in the center probe 1.
A common laser gas outlet 19 is provided, whereby the laser gas flows from the anode electrode holder 11 to the center block 1 in the laser discharge tube 3; Anode electrode holder 1
5 and flows toward center block 1.

Pin-shaped anode electrodes 21 and 23 are attached to the anode electrode holders 11 and 15, respectively.

As clearly shown in FIG. 2, electrode support pins 25 and 27 made of tungsten are integrally provided midway in the axial direction of each of the laser discharge tubes 3 and 5 by insert molding. Electrode support pins 5.27 each extend through the end wall of each of the laser discharge tubes 3 and 5, and a ring-shaped cathode electrode 29.3 is provided at the tip inside the laser discharge tube.
1 is fixedly supported. The electrode support pin 25.27 and the cathode electrode 29.31 may be connected integrally by an appropriate conductive welding means such as welding or brazing, and the cathode electrode 29.31 is connected to the electrode support pin 25.27 The laser discharge tubes 3.5 are arranged concentrically with the laser discharge tubes 3.5 with a mounting precision of 3.5. Note that the cathode electrode 25.
The inner diameter of 27 may be approximately the same as the inner diameter of laser discharge tubes 3 and 5.

Further, in the illustrated embodiment, the laser discharge tubes 3 and 5 are
Each of the portions where the cathode electrodes 29 and 31 are arranged has a larger diameter and a larger passage cross-sectional area than the other portions, and the diameters are the same on both sides. As a result, the laser beam in the laser discharge tube 3 or 5 is transmitted to the laser discharge tube 3.
There is no collision with the pipe wall of No.5.

Although the present invention has been described in detail with respect to specific embodiments above, the present invention is not limited thereto.
It will be apparent to those skilled in the art that various embodiments are possible within the scope of the invention.

[Effects of the Invention] As can be understood from the description of the embodiments as described above, in the gas laser oscillator according to the present invention, the cathode electrode is fixed inside the laser discharge tube by the electrode support pin provided integrally with the laser discharge tube. Since the cathode electrode is fixedly disposed within the laser discharge tube, the cathode electrode is enclosed within the laser discharge tube, and there is no need to divide the laser discharge tube into two glass tubes. As a result, the number of parts can be reduced compared to the conventional technique, and maintenance such as assembly and replacement of the laser discharge tube and the cathode electrode can be performed more easily than in the conventional technique. The electrode support pins that are directly supported by the laser discharge tube are made of tungsten, which has a coefficient of thermal expansion comparable to that of the glass that makes up the laser discharge tube. As a result, the connection between the glass laser discharge tube and the electrode support pins and the sealing of the cathode electrode within the laser discharge tube can be performed with high reliability.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing one embodiment of a gas laser oscillator according to the present invention, and FIG. 2 is a longitudinal sectional view showing one embodiment of a laser discharge tube used in the gas laser oscillator according to the present invention. 1... Center block 3.5... Laser discharge tube 13.17... Laser gas inlet 19... Laser gas outlet 21.23... Anode electrode 25.27... Electrode support pin 29.31.・Cathode electrode

Claims (1)

[Claims] In a gas laser oscillator in which a cathode electrode is provided midway in the axial direction of a glass laser discharge tube, a tungsten electrode support pin extending through the tube wall of the laser discharge tube is integrally provided. A gas laser oscillator, wherein a ring-shaped cathode electrode is fixedly arranged within the laser discharge tube by the electrode support pin.