JPH09252154A - Laser oscillator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the oscillation efficiency of a laser beam by forming a pair of electrodes, one of which is an L-shaped electrode at the downstream, and supporting the top end of this electrode in a direction crossing the flow of a gas. SOLUTION: Two pairs of series connected electrodes are disposed at mutually opposite positions between laser tubes 2 and the ground electrodes 12 located at the downstream are shaped each substantially like an L letter such that the one end of each electrode 12 is coupled with a protrusion 2d of the tube 2 and the other end 12b is bent inwards at an obtuse angle from its radially extending coupling part 12a. Thus, the top end 12b is supported across the axial line of the tube 2 and located at a position slightly shifted radially outwards.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser oscillator, and more particularly to a laser oscillator having at least a pair of electrodes in a laser tube.

[0002]

2. Description of the Related Art Conventionally, as a laser oscillator, for example, Japanese Patent Laid-Open No. 6-291391 is known. In this laser oscillator, a plurality of sets of electrodes are provided in the axial direction of the laser tube, and each electrode is formed in an L shape, and
The tips of the electrodes of each of the sets are supported so as to face each other.

[0003]

However, it has been pointed out that the above-mentioned conventional laser oscillator has a drawback that the oscillation efficiency of laser light is poor.

[0004]

[Means for Solving the Problems] In view of such circumstances,
The present invention includes at least a pair of electrodes arranged in a laser tube, and a direct current power source for applying a high voltage to the electrodes, supplies gas into the laser tube, and causes gas to flow in the laser tube. In the laser oscillator configured as described above, of the pair of electrodes, the electrode on the downstream side in the flow direction of the gas is formed into a substantially L shape, and the tip of the electrode intersects the flow direction of the gas. It was supported in the direction of doing.

[0005]

With this structure, the oscillation efficiency of laser light can be improved as compared with the conventional case.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. In FIG. 1, a laser oscillator 1 comprises two laser tubes 2 having the same structure and arranged vertically in the axial direction thereof. One end portion of each of the laser tubes 2 is supported by the manifold 3 serving as a common support member, and the other end portion of each laser tube 2 is supported by the manifolds 4A and 4B serving as support members. The laser gas supply means 5 includes manifolds 4 at both ends.
The laser gas is supplied into each laser tube 2 via A and 4B, the laser gas in each laser tube 2 is discharged from the central manifold 3 to the outside, and the laser gas is again returned from the manifolds 4A and 4B at both ends. It can be circulated and supplied into the laser tube 2. The laser gas supply means 5 includes, on the downstream side of the central manifold 3, a heat exchanger 6 for cooling the laser gas discharged from each of the laser tubes 2, and a blower 7 on the downstream side of the heat exchanger 6. The connection tubes 8 connect the manifold 3 and the heat exchanger 6 and the heat exchanger 6 and the blower 7, respectively. The blower 7 is capable of sending laser gas in two directions. One of the two branched laser gases from the blower 7 is a connecting tube 8A, a heat exchanger 9A for heating the laser gas, and the manifold 4
A is supplied to one laser tube 2 via A, and the other laser gas is supplied to the other laser tube 2 via a connection tube 8B, a heat exchanger 9B for heating the laser gas, and the manifold 4B. . Each of the connection tubes 8, 8A, 8B is manufactured from a non-insulating material, and each of the connection tubes has a cylindrical shape. Further, one manifold 4B is provided with a reflection mirror 10 that reflects the laser light excited in the laser tube 2, and the other manifold 4A reflects the laser light excited in the laser tube 2. An output mirror 11 that transmits the laser light is provided. The reflection mirror 10 and the output mirror 11 are 2
It is provided so as to face the axis of the laser tube 2 of the book, and the laser light resonated by the pair of mirrors 10 and 11 can be emitted toward the left side from the output mirror 11. There is. Laser tube 2
Each of the electrodes has a pair of electrodes 1 at positions facing each other.
Two pairs of electrodes 2 and 13 are provided in series, and one of the pair of electrodes is disposed on the end side of each laser tube 2 as the ground electrode 12, that is, on the side of the manifolds 3, 4 </ b> A and 4 </ b> B. Is disposed at the center of each laser tube 2. In this embodiment, the ground-side electrode 12 is the anode and the non-ground-side electrode 13 is the cathode. The ground side electrode 1
2 may be a cathode and the non-ground side electrode 13 may be an anode.
The pair of electrodes 12 and 13 are connected to a direct current high voltage circuit 15 as a power source via an electric wire 14, and between the pair of electrodes 12 and 13 in a state where a laser gas is circulated in the laser tube 2. By applying a high voltage, it is possible to cause discharge between the pair of electrodes to excite the laser gas. 2 is an enlarged cross-sectional view of the laser tube 2 on the left side of FIG. 1. The thickness of the laser tube 2 is the same throughout the axial direction, but the left and right end portions and the central portion in the axial direction have a large diameter portion 2a. In addition, the other portion is made the small diameter portion 2b, and the small diameter portion 2b
A continuous portion of b and the large diameter portion 2a is connected by a taper portion 2c. Then, as described above, the ground side electrodes 12 (anode) are provided on the large diameter portions 2a at the left and right ends of the laser tube 2, and the non-ground side electrodes 13 (cathode) are provided on the large diameter portion 2a on the center side of the laser tube 2. It is provided. The large diameter portion 2a of the laser tube 2 is formed with a protruding portion 2d that radially protrudes outward in the radial direction.
A rod-shaped ground-side electrode 12 (anode) or non-ground-side electrode 13 (cathode) is pierced in the center of d in the radial direction and is fixed with an intermediate glass. This intermediate glass is for each electrode 1
It is provided for the purpose of absorbing the thermal expansion when 2 and 13 thermally expand. As shown in FIGS. 3, 5 and 7, the protrusions 2d are provided at six positions at equal intervals in the circumferential direction of the laser tube 2, and each protrusion 2d has a ground side electrode 12 (anode) or a non-electrode. A ground side electrode 13 (cathode) is provided. That is, in this embodiment, the ground electrode 1
As for 2 (anode) or the non-ground side electrode 13 (cathode), 6 pieces in the circumferential direction form one set. Then, as shown in FIG. 6, the non-ground side electrode 13 (cathode) provided on the large diameter portion 2a on the center side of the laser tube 2 is L as a whole.
It is shaped like a letter. That is, the electrode 13 (cathode) is
A connecting portion 13a that is connected to the protruding portion 2d of the laser tube 2 and is supported along the radial direction of the laser tube 2.
And a tip portion 13b bent at a right angle from the inner end of the connecting portion 13a. The electrode 13 (cathode) thus configured supports the tip 13b of the electrode 13 toward the ground side electrode 12 (anode). That is, of the non-ground side electrodes 13 (cathode) shown in FIG. 2, the tip portion 13b of the electrode 13 (cathode) located on the right side.
Supports the laser gas toward the downstream side in the flow direction. On the contrary, the non-ground side electrode 13 shown in FIG.
Of the (cathode), the tip portion 13b of the electrode 13 (cathode) located on the left side is the ground side electrode 12 (anode) on the left side.
Support towards. That is, the laser gas is supported toward the upstream side in the flow direction. As shown in FIG. 5, the tip portion 13b of the electrode 13 (cathode) is located at substantially the same position as the inner peripheral surface of the small diameter portion 2b in the radial direction of the laser tube 2. On the other hand, the ground electrode 12 (anode) located on the upstream side in the laser gas flow direction is formed in a straight rod shape as shown in FIGS. 7 and 8. The inner end of the ground electrode 12 (anode), that is, the tip is located substantially at the same position as the inner peripheral surface of the small diameter portion 2b in the radial direction of the laser tube 2. Therefore, in this embodiment, the efficiency of exciting the laser light is improved by improving the ground electrode 12 located on the downstream side in the laser gas flow direction as follows. That is, as shown in FIGS. 3 and 4, the ground-side electrode 12 located on the downstream side is substantially L-shaped as a whole. The ground electrode 12 is connected to the protruding portion 2d of the laser tube 2 and is bent at an obtuse angle continuously from the connecting portion 12a extending in the radial direction of the laser tube 2 and the inner end of the connecting portion 12a. And a tip portion 12b. In the present embodiment, the tip portion 12 of the ground side electrode 12 on the downstream side configured as described above is used.
As shown in FIG. 4B, the tip portion 12b of the ground-side electrode 12 is supported so as to intersect the axial direction of the laser tube 2. Further, as shown in FIG. 3, the tip portion 12b of each ground-side electrode 12 thus supported is located at a position slightly outward in the radial direction from the inner peripheral surface of the small diameter portion 2b of the laser tube 2. are doing. Further, the direction of the tip portion 12b of each ground electrode 12 is tangential to the inner peripheral surface of the small diameter portion 2b of the laser tube 2 and is directed in the same direction. The angle formed by the connecting portion 12a and the tip portion 12b of the ground electrode 12 is preferably about 120 degrees. Further, FIG.
Since the laser tube 2 on the right side in FIG. 2 has the same structure as the above-mentioned laser tube 2 on the left side based on the flowing direction of the laser gas, the description thereof will be omitted. In this embodiment described above, the ground side electrode 12 (anode) on the downstream side in the laser gas flow direction is substantially L-shaped, and the tip portion 12b is arranged so as to intersect the laser gas flow direction. There is. This makes it possible to improve the oscillation efficiency of the laser light when exciting the laser light. FIG. 9 shows the result of an experiment comparing the present example with the prior art regarding the oscillation efficiency when exciting laser light. As can be understood from the experimental results shown in FIG. 9, it can be understood that according to the present embodiment, the oscillation efficiency in exciting the laser light is improved as compared with the conventional case. As a conventional technique in this experiment, an experiment was conducted on a laser oscillator disclosed in Japanese Patent Laid-Open No. 6-291391. That is, not only the electrode 13 on the center side of the laser tube in this embodiment,
The ground side electrode 12 is L as well as the non-ground side electrode 13.
An experiment was carried out on a laser oscillator in which the tips of the electrodes 12 and 13 which are formed in a letter L shape and are made L-shaped are opposed to each other and supported in the laser tube 2. (Second Embodiment) Next, FIG. 10 shows a simplified second embodiment of the present invention. In contrast to the above-described first embodiment in which two pairs of electrodes 12 and 13 are arranged in one laser tube 2, in the second embodiment, one pair of electrodes 1 and 13 is arranged.
2 and 13 are arranged. That is, L is provided on the upstream side in the laser gas flow direction in the laser tube 2.
A letter-shaped electrode 13 serving as an anode is arranged, and its tip portion 13b is supported toward the downstream side. On the other hand, the electrode 12 on the downstream side in the laser gas flow direction is a cathode, and is configured in the same manner as in the first embodiment,
The tip portion 12b is supported so as to cross the axial direction of the laser tube 2 as in the case of the first embodiment. Also with the second embodiment having such a configuration, the same effect as that of the first embodiment described above can be obtained. (Third Embodiment) As another embodiment, the laser tube 2 may be constituted only by the portion on the right side of the axial center of the laser tube 2 in the first embodiment shown in FIG. Even with such a configuration, it is possible to obtain the same effects as those of the above-described embodiments.

[0007]

As described above, according to the present invention, it is possible to obtain an effect that the oscillation efficiency of laser light can be improved as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is an overall layout drawing showing an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a laser tube 2 on the left side of FIG.

FIG. 3 is a sectional view taken along the line III-III in FIG. 2;

FIG. 4 is an enlarged view of a main part of FIG. 3;

FIG. 5 is a sectional view taken along the line VV in FIG. 2;

FIG. 6 is an enlarged view of a main part of FIG.

7 is a sectional view taken along the line VII-VII in FIG.

FIG. 8 is an enlarged view of a main part of FIG.

FIG. 9 is a diagram comparing the performances of the present embodiment and the related art.

FIG. 10 is a sectional view showing another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laser oscillator 2 ... Laser tube 5 ... Laser gas supply means 12, 13 ... Electrode 15 ... DC high voltage circuit (DC power supply)

Claims (2)

[Claims] 1. A laser tube comprising at least a pair of electrodes arranged in the laser tube and a direct current power source for applying a high voltage to the electrodes, supplying gas into the laser tube and circulating the gas inside the laser tube. In the laser oscillator configured as described above, of the pair of electrodes, the electrode on the downstream side in the gas flow direction is formed into a substantially L-shape, and
A laser oscillator in which the tip of the electrode is supported in a direction intersecting with the gas flow direction. 2. Two pairs of the electrodes are sequentially arranged along the axial direction of the laser tube, and the most downstream electrode in the gas flow direction of the two pairs of electrodes is formed in an L shape. The laser oscillator according to claim 1, wherein the laser oscillator is a laser oscillator.