JPS59188189A - Co2 laser device - Google Patents

Abstract

PURPOSE:To perform high repetition of laser oscillation by flowing gas, further rotating electrodes, thereby completely removing discharge product which disturbs the high speed repetition of laser oscillation from the discharge space. CONSTITUTION:A discharge procut produced due to discharge is forcibly flowed to the downstream side of the discharge space 22 via the stream 21 of laser gas. At this time, electrodes 11, 12 are rotated around rotational shafts 14, 15. Thus, a boundary layer in the electrode surface is not formed. Accordingly, the product does not remain in the space 22. Thus, high speed repetition oscillation can be performed. For example, when the electrodes 11, 12 are rotated at 30 times/sec the laser can be oscillated at 120pps. The moving time of the electrode 13 due to rotation is sufficiently long as compared with the discharge continuing time. Consequently, the discharge is not disturbed by the rotation of the electrodes.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides T Ib
A C(,) 2 ○T related to v-the device
I? , A C02 laser, when a large amount of discharge products (mainly 02 molecules) becomes present in the discharge space, the discharge shifts to arc emission 'YL. Arc discharge is a discharge inappropriate for excitation of a laser, and laser oscillation stops when the discharge shifts to arc discharge. Incidentally, as the number of repetitions of laser oscillation increases, the amount of discharge products increases.

Therefore, if the repetition rate of laser oscillation is increased, it becomes easier to shift to arc discharge, so in order to increase the repetition rate of laser oscillation, it is necessary to devise a method for removing discharge products from the discharge space.

In the conventional high-speed repetition TBAOO2 laser device, discharge products are removed to the outside of the discharge space by flowing laser gas. By the way, in this case the discharge electrode -
A boundary layer (hereinafter simply referred to as boundary layer) is formed on the surface of which gas stagnates or flows very slowly. Since the boundary layer gas contains discharge products, even if the laser gas flows, the discharge products cannot be completely removed from the discharge space.

However, the amount of discharge products in the boundary layer is smaller than the amount of discharge products present in the discharge space when there is no gas flow, and therefore, laser oscillation can be repeated at a faster rate with gas flow than without. However, at higher repetition rates, a large amount of discharge products in the boundary layer is produced and the discharge transitions to arc discharge. In other words, there is a limit to repetition.

An object of the present invention is to completely remove the discharge products that impede high-speed repetition of laser oscillation from the discharge space, thereby achieving high-speed repetition of laser oscillation.

According to the present invention, by flowing gas and rotating the electrode, a high-speed repetition 'r EAO02 laser is used in which discharge products are quickly removed out of the discharge space without forming a boundary layer on the electrode surface. can get.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to drawings showing embodiments.

FIG. 1 is a perspective view showing the electrode portion of the embodiment, and FIG. 2 is a sectional view thereof. The cathode side electrode 11 and the anode side electrode 12 are each constructed using four electrode elements 13 of the same shape, and rotate in the direction of the arrow (FIG. 2-) around a 64 rotation axis 14°15.

During single discharge, one of the electrode elements il'j of the anode side electrode 11 always faces one of the electrode elements of the cathode side electrode 12 with the discharge space 22 in between. Laser gas flows in the direction of arrow 21.

In the TEAOO laser shown in FIG. 1, discharge products produced by discharge are swept downstream of the discharge space 22 by the flow 21 of the laser gas. At this time, electrode 11
．． Since the electrodes 12 are each rotated around the rotation axis 14, 15, no boundary layer is formed on the electrode surface. Therefore, no discharge products remain in the discharge space 22. This allows high-speed 1, ":L repeating oscillation. For example, if the electrodes 11' and '12 are rotated at 30 times/s, 120 I
) I) S can be used to emit a laser. Note that since the movement time of the i-pole 13 due to rotation is sufficiently longer than the discharge duration, the discharge is not disturbed by the rotation of the electrode.

By configuring the electrodes 11 and 12 using a larger number of electrode elements 13 or by increasing the rotational speed of the rotation axis of the electrode, it is possible to obtain laser oscillation at several hundred pps without increasing the gas flow rate. .

Furthermore, since there is no need to place a turbulence generator in the gas flow path, the resistance experienced by the gas is small, and to obtain the same gas flow rate, this device requires less power.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an electrode section showing an embodiment of the present invention,
FIG. 2 is a sectional view thereof. DESCRIPTION OF SYMBOLS 11... Cathode side electrode, 12... Anode side electrode, 13... Electrode element, 14.15... Rotation shaft, 21... Gas flow direction, 22... Discharge space.

Claims (1)

[Claims] In a C02 laser device equipped with a pair of reflecting mirrors constituting a resonator, a discharge tube installed between the reflecting mirrors, and electrodes placed opposite each other in the discharge tube, a laser gas is caused to flow and further C, characterized in that at least one of the anode side electrode and the cathode side electrode rotates one of the electrodes.
02 laser device.