JP2759934B2 - Dust removal device in gas laser device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas laser device such as a carbon dioxide gas laser or an excimer laser device, and more particularly, to dust removal disposed near a front mirror and a rear mirror forming an optical resonator of a laser oscillator. It concerns the device.

[0002]

2. Description of the Related Art In a gas laser apparatus of this type, dust mixed during manufacturing or inspection, or dust composed of fine particles generated by depletion of an electrode portion due to discharge during laser oscillation floats in a laser chamber. This may cause various troubles. In particular, when this dust adheres to the front mirror or the rear mirror forming the optical resonator of the laser oscillator, there has been a problem that its reflection function and transmittance are reduced, and eventually it becomes unusable. For this reason, a dust removing means has conventionally been provided in the circulating flow of the laser gas (Japanese Utility Model Publication No. 2-17491, Japanese Utility Model Publication No. 59-169057), and as shown in FIG. Then, laser gas purified by a filter or the like (not shown) is blown through the pipe 102 to slightly increase the internal pressure of the region 103 to prevent dust from entering.

[0003]

However, of the prior art, the former dust removing means indirectly acts to prevent dust from adhering to the inner surface of the mirror due to the most problematic discharge of the electrode portion. Just doing so was uncertain and not efficient. In this regard, the latter dust removing means has a corresponding effect,
The amount of air blown to 03 is not so large due to various restrictions, and a vortex may also be generated in the air flow, and furthermore, since the electrode portion and each mirror are disposed in a close positional relationship, the electrode portion has It was practically difficult to completely prevent the generated dust from entering the area 103.

The present invention has been made under such circumstances, and with a simple structure, particularly, dust generated at an electrode portion is caught before reaching the inner surface of the mirror, and dust generated on the inner surface of the mirror is captured. Can reduce the adhesion of
It is an object of the present invention to provide a dust removing device for a gas laser device in which removal of trapped dust and attachment / detachment of a dust catching member at the time of component replacement are easy and an accurate mounting state can be obtained.

[0005]

According to the present invention, in order to solve the above-mentioned problems, irregularities for accumulation of dust are formed on the inner surface near the inside of a front mirror or a rear mirror forming an optical resonator of a laser oscillator. A baffle for dust capture is arranged, and a magnet is attached to the outside of the baffle for dust capture so that dust can be sucked and captured by the baffle, and a flange portion is formed on the baffle, It is characterized in that the flange portion is detachably mounted by being sandwiched between a mirror housing and a mirror holder.

[0006]

According to the above technical means, since the dust generated by the discharge of the electrode portion contains a large amount of metal,
When the mirror enters the vicinity of the inside of the front mirror or the rear mirror, it is attracted by the magnetic action of the magnet and is trapped and accumulated in the concave and convex concave portions formed in the baffle for dust trapping. Adhesion can be reduced. In addition, since a configuration is adopted in which the flange portion is formed on the baffle and the flange portion is sandwiched between the mirror housing and the mirror holder to be removably mounted, the number of components for the mounting is reduced, and the number of components is reduced. At the time of removal of the dust and replacement of parts, the attachment / detachment work of the baffle as the dust catching member becomes extremely simple, and an accurate mounting state can be achieved via the flange portion.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a laser chamber, and a laser gas sealed in the laser chamber 1 circulates on a path passing between the electrodes 3 and 3 by a blowing action of a circulation fan 2.
Reference numerals 4 and 5 denote a front mirror portion and a rear mirror portion, respectively. In an optical resonator formed therebetween, a laser gas is excited by the electrodes 3 and 3 to continue laser oscillation as in a general gas laser device. . Reference numeral 6 denotes a connection portion for driving the circulation fan 2. In the figure, reference numeral 7 denotes a laser gas supply / discharge pipe system which is connected to the laser chamber 1 and through which the gas is exhausted or replenished as necessary. A dust removal mechanism 8 for removing dust contained in the laser gas is provided in the laser gas supply / discharge pipeline system 7 and connected to a supply / discharge switching valve 9. This dust removal mechanism 8
Is a device that captures dust by utilizing the phenomenon that the dust component travels straight due to its own inertia force when supplying and discharging the laser gas. The dust capturing unit 10 includes a straight traveling path and a magnet attached to the outside thereof. , 11 are formed. The valve 9 is used to switch the pipeline system 7 on the side of the laser chamber 1 to a cutoff state or a communication state to the pipelines 12 and 13, so that the laser chamber 1 is not shown when exhausting the laser gas. It is selectively connected to the side of the pipe 12 connected to a suction pump or the like not shown, and to the side of the pipe 13 connected to a not-shown laser gas cylinder or the like when replenishing laser gas.

Next, a description will be given of a dust removing device provided in the front mirror section 4 or the rear mirror section 5, which is a feature of the present invention, with reference to FIGS. FIG.
FIG. 3 is an enlarged longitudinal sectional view of a front mirror section 4 as an example of a mirror section, and FIG. In the figure,
Reference numeral 14 denotes a front mirror which is supported via a mirror housing 15 so as to be adjustable with respect to a chamber wall 16 forming the laser chamber 1. 17 is the front mirror 1
A baffle for dust capture arranged near the inside of 4,
Irregularities 18 for dust accumulation are formed on the inner surface, and are detachably attached to the mirror housing 15 via a flange portion 19. Reference numerals 20 and 21 denote mirror holders for holding the front mirror 14, which hold the front mirror 14 from both sides via shims (not shown) on the inside, and furthermore, use the fastening means such as bolts 22 to secure the front mirror 14 to the flange portion 23 of the mirror housing 15. The front mirror 14 is fixed by tightening. At this time, the flange 19 of the baffle 17 for capturing dust is also simultaneously held between the mirror holder 20 and the flange 23 of the mirror housing 15, so that the baffle 17 is also fixed to the mirror housing 15 at the same time. . Further, a magnet is disposed on the outer periphery of the mirror housing 15 so as to face the baffle 17 for capturing dust, 24 and 25 are magnetic poles of the magnet, and 26 is a U-shaped part forming a magnetic circuit.
In the drawings, reference numerals 27 to 29 denote support bolts for the wall portion 16 of the mirror housing 15, and reference numerals 30 and 31 denote fine adjustment means relating to the support state. In the above description, the front mirror unit 4 has been mainly described, but the rear mirror unit 5 also has the same dust removing device.

However, dust mixed in the laser chamber 1 at the time of manufacture or inspection or dust composed of fine particles or the like generated due to discharge of the electrode portion floats, and this floats on the mirrors of the front mirror 4 or the rear mirror 5. When the dust enters the housing 15, the dust caused by the discharge of the electrode, which is particularly problematic, contains a large amount of metal due to the magnetic action of the magnet attached to the outside of the baffle 17 for capturing dust. Is efficiently sucked and the unevenness 18
Accumulate in the recesses of Further, when the accumulation progresses and the dust exceeding a predetermined amount accumulates on the unevenness 18, the bolt 22 is loosened and the baffle 17 is removed together with the mirror holders 20, 21 to remove the accumulated dust. Just replace it with a new baffle and re-attach. In this case, the baffle 17
Is configured to be simultaneously clamped and mounted between the mirror holder 20 and the flange portion 23 of the mirror housing 15, so that the number of mounting components is small and the work of attaching and detaching the baffle 17 is extremely simple. Moreover, an accurate mounting state can be obtained very easily via the flange portion 19. By repeating the above dust removal and baffle replacement operations to keep the irregularities 18 clean, the baffle 17 can reliably capture the dust in the laser gas just before reaching the inner surface of each mirror. In addition, it is possible to always effectively prevent dust from adhering to the inner surface of each mirror.

[0010]

According to the present invention, the following effects can be obtained based on the above configuration. (1) It is possible to efficiently remove dust generated by the discharge of the electrode portion which is disposed close to each mirror portion and has a large adverse effect on the inner surface of the mirror. That is, since the dust generated by the exhaustion of the electrode contains a large amount of metal, when the dust enters the vicinity of the inside of the front mirror or the rear mirror, it is attracted by the magnetic action of the magnet, and the dust is collected. Are trapped and accumulated in the concave and convex portions formed on the baffle, and can be efficiently removed before the inner surface of the mirror with a simple configuration. (2) If a predetermined amount of dust accumulates on the uneven portion formed on the dust capturing baffle, remove the baffle and remove the accumulated dust, or replace the baffle with a new baffle and reattach. Can be easily handled. (3) In addition, since the baffle for capturing dust is configured to be mounted by sandwiching the flange formed on the baffle between the mirror housing and the mirror holder, the number of parts for mounting is reduced, and the baffle is reduced. The attachment / detachment work becomes extremely simple, and an accurate mounting state can be easily obtained via the flange portion. (4) Since it is compatible with other conventional dust removing means,
When used together, it can complement each other and completely prevent dust from adhering to the inner surface of the mirror,
It is more effective for improving the life of the mirror.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention.

FIG. 2 is an enlarged vertical sectional view of a front mirror unit in the embodiment.

FIG. 3 is a sectional view taken along line XX of FIG.

FIG. 4 is an enlarged longitudinal sectional view of a front mirror section in a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laser chamber, 2 ... Circulation fan, 3 ... Electrode, 4 ...
Front mirror section, 5 ... Rear mirror section, 6 ... Connection section, 7
… Laser gas supply / discharge pipeline system, 8… Dust removal mechanism, 9
... Valve, 10, 11 ... Dust capturing part, 12,13 ... Pipe, 14 ... Front mirror, 15 ... Mirror housing,
16: chamber wall, 17: baffle for dust capture, 1
8 Unevenness, 19 Flange, 20, 21 Mirror Holder, 22 Bolt, 23 Flange, 24, 25 Magnetic Pole, 26 U-Shape, 27-29 Support Bolt, 30,
31 ... Fine adjustment means

Claims (1)

(57) [Claims] 1. A dust capturing baffle having irregularities for accumulating dust on its inner surface is disposed near an inside of a front mirror or a rear mirror forming an optical resonator of a laser oscillator. A magnet is attached to the outside of the baffle so that dust can be sucked and captured by the baffle, and a flange portion is formed on the baffle,
A dust removing device in a gas laser device, wherein the flange portion is detachably mounted by being sandwiched between a mirror housing and a mirror holder.