JPH06204589A - Electrode for high-frequency discharge laser oscillator - Google Patents

Abstract

PURPOSE:To provide an electrode capable of conducting discharge stably by preventing the partial concentration of discharge while ensuring insulation with a peripheral section in a high-frequency discharge laser oscillator. CONSTITUTION:The title electrode is composed of oppositely faced upper and lower metallic electrodes 1, 3, upper and lower first dielectrics 5, 7 shielding these electrodes 1, 3 from a laser gas flow and upper and lower second dielectrics 9, 11 filled among the end faces of the upper and lower metallic electrodes 1, 3 and the upper and lower first dielectrics 5, 7. The electrode consists of the combination of the upper and lower first dielectrics 5, 7 having a dielectric constant of 2-200 and the upper and lower second dielectrics 9, 11 having a dielectric constant of 2-10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode of a high frequency discharge laser oscillator.

[0002]

2. Description of the Related Art FIG. 3 is a schematic view of a conventional high-frequency discharge triaxial orthogonal carbon dioxide laser oscillator, in which a discharge space 15 provided in a vacuum vessel 13 in which a laser gas G circulates has upper and lower metal electrodes 1 and 3. The opposing surfaces are shielded and protected from the gas flow by the upper and lower (first) dielectrics 5 and 7 made of glass or ceramics, and a high frequency power source is connected to each to excite the laser gas G by discharge. ,
Amplification is performed by a plurality of mirrors (not shown) provided in the discharge space 15, and a laser beam is generated in a direction perpendicular to the paper surface.

[0003]

Since the metal electrode of the high-frequency discharge laser oscillator as described above has a finite width, the electric field is concentrated at the left and right end portions due to the end effect, and particularly, the right end portion of the metal electrode Since it hits the downstream end, local concentration of the discharge occurs as shown in FIG. 3 together with the rise in the temperature of the laser gas. This local concentration of the electric field can be reduced by giving curvature to the left and right ends of the electrode, but it is necessary to make the curvature considerably large in order to relax the electric field and obtain a stable discharge. However, when the curvature is increased, the contact area between the metal electrode and the dielectric is reduced, the discharge voltage is increased, and a new problem occurs in the breakdown voltage around the electrode.

Further, since the metal electrode and the dielectric are heated by the heat generated at the time of discharge and the dielectric loss, it is necessary to cool them. Therefore, the portion of the metal electrode which is in contact with the atmosphere causes dew condensation. However, there is a problem in that the insulation from the periphery is significantly reduced.

The present invention was devised in view of the above problems, and it is possible to prevent local concentration of discharge and to secure insulation from the peripheral portion and to perform stable discharge. It is intended to provide electrodes for an oscillator.

[0006]

In order to achieve the above object, the electrode of the high frequency discharge laser oscillator of the first invention is
Opposing upper and lower metal electrodes 1 and 3, upper and lower first dielectrics 5 and 7 for shielding and protecting these, left and right end surfaces of the upper and lower metal electrodes 1 and 3, and the upper and lower first dielectrics Upper and lower second dielectrics 9, 11 filled between 5, 7
It consists of and.

The electrodes of the high frequency discharge laser oscillator of the second invention are the upper and lower first dielectrics 5, 7 in the first invention.
Having a dielectric constant of 2 to 200 is used, and the upper and lower second dielectrics 9 and 11 have a dielectric constant of 2 to 10 and the first dielectric 5
The dielectric constant of is larger than that of the second dielectric constant 7 is used.

[0008]

With this structure, the surfaces of the upper and lower metal electrodes 1 and 3 on the gas flow side are shielded from the gas flow by the upper and lower first dielectrics 5 and 7, and their wear and deterioration are prevented. . The left and right ends are the upper and lower second dielectrics 9, 1
Since it is filled with 1, the electric field is unlikely to concentrate even if the curvature of this end is not particularly increased. Also,
Since the ends are shielded from the atmosphere by the dielectric having a low thermal conductivity, dew condensation on the upper and lower second dielectrics 9 and 11 is unlikely to occur. Further, the dielectric constants of the upper and lower first dielectrics 5 and 7 and the second dielectrics 9 and 11 are set in consideration of the above-mentioned curvature and the spread of the discharge space due to the upper and lower second dielectrics 9 and 11, It was set to 2 to 200 and 2 to 10, respectively.

[0009]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a schematic view of an electrode according to an embodiment of the present invention. As shown, the surfaces of the upper and lower metal electrodes 1 and 3 on the gas flow side are shielded from the gas flow by the upper and lower first dielectrics 5 and 7, and relatively small R is attached to the left and right ends. The upper and lower first dielectrics 5,
The upper and lower second dielectrics 9 and 11 are filled between the upper and lower parts.

Glass (dielectric constant 2 to 3), ceramics (dielectric constant 7 to 10), etc. are used for the upper and lower first dielectrics 5 and 7, and upper and lower second dielectrics 9 and 11 are used. In consideration of the adhesion to the upper and lower metal electrodes 1 and 3 and the upper and lower first dielectrics 5 and 7, the fluid silicon rubber (dielectric constant 2 to 4) is vacuum degassed when the electrodes are manufactured. Is being used. This silicone rubber is hardened by a curing agent or heating.

The left and right end portions of the upper and lower metal electrodes 1 and 3 of the present invention have a relatively small curvature as described above in order to suppress the rise of the discharge voltage, and the concentration of the electric field generated in those portions is It is suppressed by the upper and lower second dielectrics 9, 11.

FIG. 2 shows that the upper and lower second dielectrics 9 and 11 spread the discharge in the discharge space (thin discharge portion). By using a material having a dielectric constant smaller than that of No. 7, it is possible to prevent unnecessary spreading of the discharge in the gas flow direction.

As described above, the upper and lower first dielectrics 5 and 7 are made of glass (dielectric constant 2 to 3), ceramics (dielectric constant 7 to 10), barium titanate (dielectric constant 200), or the like. Is about 2 to 200, and the upper second dielectric 9 is made of glass, silicon rubber, ceramics or the like having a dielectric constant of about 2 to 10.

In this embodiment, the upper and lower metal electrodes 1,
Although the surface of No. 3 opposite to the gas flow is open to the atmosphere, this part may be covered with the upper and lower second dielectrics 9 and 11. This makes it possible to prevent dew condensation on this part.

In this embodiment, the electrodes of the triaxial orthogonal type carbon dioxide gas laser oscillator have been described, but the present invention is also applied to the electrodes of the high-speed axial flow type gas laser oscillator.

[0016]

As can be understood from the above description, the electrodes of the high-frequency discharge laser oscillator of the present invention have the structure described in the claims, so that the local concentration of the discharge can be prevented and the surroundings can be prevented. It is possible to ensure stable insulation from the parts and perform stable discharge.

[Brief description of drawings]

FIG. 1 is a schematic diagram of a configuration of an embodiment of the present invention.

FIG. 2 is an explanatory view of the operation of the embodiment of the present invention.

FIG. 3 is a schematic view of a conventional high-frequency discharge triaxial orthogonal carbon dioxide laser oscillator.

[Explanation of symbols]

 1 Upper Metal Electrode 3 Lower Metal Electrode 5 Upper First Dielectric 7 Lower First Dielectric 9 Upper Second Dielectric 11 Lower Second Dielectric

Claims (2)

[Claims] 1. Upper and lower metal electrodes 1, 3 facing each other,
Upper and lower first dielectrics 5, 7 that shield them from the laser gas flow, and an upper part filled between the left and right end surfaces of the upper and lower metal electrodes 1, 3 and the upper and lower first dielectrics 5, 7. , An electrode of a high-frequency discharge laser oscillator, which comprises a lower second dielectric 9 and 11. 2. The upper and lower first dielectrics 5, 7 have a dielectric constant of 2-200, and the upper and lower second dielectrics 9, 11 have a dielectric constant of 2-10. 2. The electrode of the high frequency discharge laser oscillator according to claim 1, wherein the dielectric constant of is larger than that of the second dielectric 7.