JPS5963785A - Gas laser device - Google Patents

Abstract

PURPOSE:To generate vibration in cooling medium, and to improve cooling capability by surrounding the outer circumference of a laser pipe by a concentric outer pipe, using the outer pipe as a path for the medium while a ring-shaped electrode with a large number of medium flowing grooves is fitted to a central section in the pipe as it is penetrated in the laser pipe and applying AC voltage to the electrode. CONSTITUTION:Electrodes 4 for discharge are set up around the openings at both ends of a laser pipe 1 with a gas inflow port 2 and a gas discharge port 3 in the vicinity of both ends, and the electrodes 4 are supplied with power from a power supply E. The outsides of the electrodes 4 are each clogged by a total reflecting mirror 5 and a partial reflecting mirror 6, the outer circumference of the laser pipe 1 is surrounded by an outer pipe 7 while the pipe 7 is positioned between the inflow port 2 and the discharge port 3, and the inside of the outer pipe is used as a cooling medium path 8. In the constitution, the ring-shaped electrode 11 to which a large number of medium flowing holes 12 are bored is fitted at the central section of the path 8 while surrounding the laser pipe, and AC voltage is applied to the electrode 11. Accordingly, the linearity of the outer pipe 7 and the laser pipe 1 are regulated while a vibration is generated in the medium and cooling capability is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a gas laser device used in medical equipment, measuring equipment, processing tools, and the like.

Conventional Structure and Problems There are several types of CO2 laser devices, but the coaxial type, which has the same optical axis, gas flow, and discharge pattern, is generally well known. In order to obtain stable high output in such a coaxial type CO2 laser device, the first requirement is the linearity of the laser optical axis, and the second requirement is to increase the cooling effect of the laser medium. has been done.

However, the straightness of glass tubes commonly used as laser tubes is poor, and this tendency becomes stronger as the tube becomes longer.Also, even when a tube with good straightness is used, both ends of the glass tube CO2 with a fixed part
Laser devices have had a problem in that the central portion of the glass tube curves due to aging and the glass tube loses its straightness, resulting in a decrease in output and a disturbance in the output mode.

In addition, the second method of increasing output, which is a cooling method, is to increase the gas density so as to increase the collisions of the laser medium itself, and to increase the temperature of the laser medium because it becomes hot due to radiation. There is a method in which a sloped spread of sand is cooled using a cooling medium.

However, the former method has the disadvantage of not being able to perform stable glow discharge due to the high operating pressure that causes glow discharge. 1. has the disadvantage of having equipment limitations. It was.

OBJECTS OF THE INVENTION An object of the present invention is to provide a gas laser device that can achieve high output by improving the straightness of the tube and the cooling rate of the cooling U115 quality.

Structure of the Invention In the gas laser device of the present invention, an outer tube is disposed concentrically to cover the outside of the laser tube, and the space sandwiched between the two tubes is used as a cooling medium flow path. It is possible to apply an AC voltage to the ring-shaped electrode by fitting a herring-shaped electrode around the circumference of the tube to the ring-shaped electrode.The double tube structure of the laser tube and the outer tube maintains the straightness of the tube, and the ring-shaped electrode can be applied to the ring-shaped electrode. By applying the AC voltage, the cooling medium in the flow path is vibrated to improve the cooling performance, and the laser medium gas in the laser tube is partially ionized to improve the gas density.

DESCRIPTION OF THE EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 11-1 to 4. In FIG. 1, l is a laser tube, which has a gas inlet 2 and a gas outlet 3 near both ends thereof. Reference numeral 4 denotes discharge electrodes disposed at both ends of the laser tube 1, which are supplied with power from a power source E.Furthermore, 5 is a total reflection mirror, and 6 is a partial reflection mirror, each of which is hermetically connected to the end of the laser tube 1. )1. The mirror surfaces of these mirrors are arranged perpendicularly to the laser tube axis, and the laser tube 1 has a greasy coating that resonates the glow emission ``13'' generated in the laser tube 1 and extracts part of the light from the total reflection mirror 6 to the outside. Reference numeral 7 denotes an outer tube that is concentrically coated on the outside of the laser tube 1, and forms a cooling medium flow path 8 between it and the laser tube 1. 9 is a cooling medium inlet, and 10 is a cooling medium outlet. 2 and 3, reference numeral 11 denotes a ring contact hole in which a large number of cooling medium flow holes 12 are formed, and the laser tube 1 is located approximately at the center of the laser tube 1 in each cooling medium flow W 8. It is fitted onto the circumferential trunk portion, and the outer circumference is brought into close contact with the inner circumferential wall of the outer tube 7.This ring shape?
13.4MT 11 has an arbitrary 1 lake wave number by AC 71i: j, E applying means? Apply an AC voltage with 11F
It is Noh.

In this way, the laser tube 1 and the outer tube 7 are made into a two-way tube 11, and the ring-shaped '1÷c frame 11 is connected to both 51 and 1.7.
The straightness of the tube can be maintained because it is reinforced by 41't iM L. ′! In addition, an AC microscope is attached to the electrode 11 on the ring 4:
The pressure is applied to the cooling medium, such as water or oil, and the laser tube 1, as well as to the laser medium gas. Molecular vibration 1tfjl can be activated 7 to enhance the cooling effect, and a part of the laser medium gas can be ionized to increase the gas injection inside the laser tube 1.

Actual failure: I/I conducted an experiment using the above-mentioned device 1, and found that when no AC voltage was applied to the ring contact IQII, the operating pressure was 30 TOrr, whereas the AC voltage By applying , it was possible to achieve fiOTorr, increase the gas density, and obtain an increase in output of about 15%. Note that in the above experimental example, the frequency of the AC voltage was set to IKH2K, but as shown in Figure 4, changing the rfd wave number of the AC voltage causes a difference in the above effect, that is, under the same AC voltage, the frequency of? tb
It has been found that the operating pressure can be increased as the temperature decreases. In the figure, curve A indicates the operating pressure of the conventional example (without the ring contact rod 11 in FIG. In this way, the straightness of the tube can be achieved, the cooling capacity of the cooling medium can be increased, and the gas density of the laser medium gas can be increased, resulting in a high output.

The above embodiment has a laser resonant structure in which the total reflection mirror 59 and the partial reflection mirror 6 are arranged in a straight line, and the total reflection mirror 5 and the partial reflection mirror 6 are provided at both ends of the discharge section. Il
In the case where the laser resonance is folded in multiple stages by an intermediate total anti-reflection mirror, and the laser resonance is severe with a terminal reflection casting and a partial reflection mirror, and both ends are partially anti-resonance J1. The present invention is also applicable to a laser resonant structure using an L mirror.

Effects of the Invention The gas laser device of the present invention can improve the straightness of the tube, improve the cooling ability of the cooling medium, and crystallize the gas density of the laser medium gas, thereby achieving high output. The effect of doing this is obtained.

[Brief explanation of drawings]

FIG. 1 shows cross sections 1', g+, and 2nd cross sections of an embodiment of the present invention.
The figure is an enlarged sectional view I of the main part, FIG. 3 is a perspective view of the ring-shaped electrode, and FIG. 4 is a characteristic diagram of the relationship between the AC voltage frequency and the operating pressure. DESCRIPTION OF SYMBOLS 1... Laser tube, 2... Gas inlet, 3... Gas outlet, 4... Electrode, 5... Total reflection tube, 6... Partial reflection mirror, 7... Outside Pipe, 8...Cooling medium flow path, 1
1...Ring-shaped""1℃4゛excuse

Claims (2)

[Claims] (1) a laser tube having a gas inlet and a gas outlet near both ends; a pair of mirrors which are sealed and connected to both ends of the laser tube and whose mirror surfaces are disposed perpendicular to the laser tube axis; A pair of discharge electrodes arranged at both ends of the tube, an outer tube having a corrugated waveform arranged 1° concentrically outward of the laser tube to form a cooling medium flow path between the tube and the cooling medium; A gas laser device comprising: a ring-shaped electrode fitted around the peripheral body of the laser tube in a medium flow path; and an AC voltage applying means for applying an AC voltage to the ring-shaped electrode. (2) The gas laser device according to claim (1), wherein the ring-shaped electrode has its outer circumference brought into close contact with the inner circumferential wall of the outer tube, and has cooling medium flow holes extending in the thickness direction formed therethrough.