JPH0317233B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a gas laser oscillator.

Configurations of conventional examples and their problems There are various types of gas laser oscillators, such as coaxial flow type, biaxial orthogonal type, and triaxial orthogonal type.
FIG. 2 shows an enlarged sectional view of the gas introduction section. In the figure, 1 is a laser tube, 2 is a total reflection mirror,
3 is an output coupling mirror, and the total reflection mirror 2 and the output coupling mirror 3 constitute an optical resonator. The outer tube 5 of the gas introduction section 4 is an inner tube, and has a double tube structure. 50
is a slit provided in the inner tube. 6 and 7
are both electrodes, and a discharge occurs between this pair of electrodes. 8 and 9 indicate the direction of flow of the medium gas. 10 is a laser output beam.

In this example, the medium gas flows in the direction of arrow 8 from both ends of the resonator, flows along the inner tube 5, is introduced into the laser tube 1 through the slit 50 provided in the inner tube, and is introduced into the laser tube 1 at the center of the resonator. is discharged in the direction of arrow 9.

With the medium gas flowing through the laser tube 1 in this manner, a discharge is caused between the electrodes 6 and 7, and a laser output beam 10 is extracted from the output coupling mirror 3.

In such gas laser oscillators, the discharge generally becomes unstable when the input power is increased.
Eventually, the glow discharge shifts to arc discharge, and it becomes impossible to obtain laser output. The high-speed flow oscillator can suppress the temperature rise of the gas by shortening the residence time of the gas in the discharge region, and can dramatically increase the amount of power introduced into the arc discharge. However, since the local increase in gas temperature is the cause of the transition to arc discharge, in order to further increase the laser power obtained per unit volume, the gas flow as well as the discharge current density must be spatially uniform. It is necessary.

In the conventional example described above, the gas flow is made turbulent by introducing a slit 50, etc., and efforts are made to obtain a uniform flow velocity distribution in order to obtain a uniform discharge current density, but when the input power is increased, the discharge Streamers may occur inside the electrode, the discharge may be locally distorted or contracted, or discharge points from the electrodes 6 may be concentrated, so that a sufficiently uniform discharge is not necessarily obtained.

OBJECTS OF THE INVENTION The present invention aims to improve the above points and enable a higher output laser oscillator.

Structure of the Invention The present invention achieves the above object, and includes a laser tube, a gas introduction part for introducing a medium gas into the laser tube, and a pipe connected to the gas introduction part.
The present invention provides a gas laser oscillator characterized in that it includes a rotating electrode part that is provided close to the laser tube side of the gas introduction part and is rotatable by a gas flow.

DESCRIPTION OF EMBODIMENTS The gas laser oscillator of the present invention is characterized by a gas introduction section, and a partially exploded perspective view of one embodiment of the gas introduction section is shown in FIG. 3, and a sectional view thereof is shown in FIG. 4. The same parts as in FIG. 1 are given the same numbers. 1 is a laser tube, 2 is a total reflection mirror, 4 is an outer tube,
5 is an inner tube, 50 is a slit, and 60 is a rotating electrode portion. A rotating electrode 61 constituting the rotating electrode section 60 is held by the outer tube 4 via a rotating bearing 62 and is rotatable. FIG. 5 shows an example of a rotating electrode. The rotating electrode 61 has diagonal blades 6 on the inside.
3 is provided.

The medium gas flowing into the gas introduction section collides with the outer wall of the inner tube 5, passes through the slit 50, and further collides with the blades 63 of the rotating electrode section 60, rotating the rotating electrode 61 while flowing into the laser tube 1. The medium gas flowing into the laser tube 1 due to the rotation of the rotating electrode 61 is sufficiently turbulent, and the laser tube 1
The flow velocity distribution of gas inside is made more uniform.

Further, the rotation of the rotating electrode 61 itself prevents concentration of discharge points, local deviation and contraction of discharge, and enables discharge with uniform current density.

The uniform gas flow distribution as well as the uniform discharge current distribution as described above increases the current threshold for transition from glow discharge to arc discharge and increases the power that can be input to the medium gas. As a result, the output power obtained per unit volume increases, and therefore a smaller and more stable laser oscillator can be constructed.

FIG. 6 shows a second embodiment of the gas introduction section of the present invention. FIG. 7 is an enlarged view of the rotating electrode. Third
The difference from the figure is that the inner tube 5 does not have a slit, and the rotating electrode 64 has a spout 65 instead. The gas passes through the jet nozzle 65 and enters the laser tube 1.
At this time, the rotating electrode 64 is rotated in the same manner as in the example shown in FIG. Rotating electrode 6
4 also serves as a turbulence generation mechanism, and the rotation of the jet nozzle 65 has the effect of making the gas flow even more turbulent, thereby increasing and stabilizing the output.

In the above embodiment, the gas flow direction is from both ends of the resonator to the center, but if the gas flow direction is from the center to both ends or divided into several sections, or if the laser tube 1 is not symmetrical, Of course, even in the case of only one direction, the same effect can be obtained if the medium gas introduction part has the above structure.

Effects of the Invention In summary, the present invention has a structure in which the electrode of the gas introduction part to the laser tube is rotated by the gas flow, and the gas flow velocity distribution and discharge current density distribution within the laser tube are made uniform. It has the advantage of increasing the laser output per unit volume and obtaining a smaller and more stable oscillator.

[Brief explanation of drawings]

Fig. 1 is an overview of a conventional discharge-excited gas coaxial flow type laser oscillator, Fig. 2 is a sectional view of a conventional gas introduction section, and Fig. 3 is a partially fragmented perspective view of the gas introduction section in an embodiment of the present invention. 4 is a cross-sectional view of the gas introduction part of FIG. 3, FIG. 5 is a three-dimensional view of the rotating electrode of the present invention, and FIG. 6 is a cross-sectional view of the gas introduction part of the second embodiment of the present invention. FIG. 7 is a three-dimensional view of a rotating electrode according to a second embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Laser tube, 2... Total reflection mirror, 3... Output coupling mirror, 4... Outer tube of gas introduction section, 5... Inner tube of gas introduction section, 6, 7... Electrode, 8, 9 ...Medium gas flow, 10...Laser output beam, 50...
...Slit, 60... Rotating electrode section, 61, 64...
... Rotating electrode, 62 ... Rotating bearing, 63 ... Vane,
65... spout.

Claims (1)

[Scope of Claims] 1. A laser tube, a gas introduction section for introducing a medium gas into the laser tube, a pipe connected to the gas introduction section, and a laser tube provided adjacent to the laser tube side of the gas introduction section. Furthermore, a gas laser oscillator characterized in that it is equipped with a rotating electrode part that can be rotated by a gas flow. 2 The gas introduction part has a double pipe structure consisting of an inner pipe and an outer pipe, and after the medium gas introduced from the pipe passes through the slit provided in the inner pipe, it is introduced into the laser tube via the rotating electrode part. A gas laser oscillator according to claim 1, characterized in that the gas laser oscillator is constructed as follows. 3. The gas laser oscillator according to claim 1, characterized in that the medium gas flowing into the gas introduction section is guided to the laser tube via a jet port provided in the rotating electrode section. .