JPS6376488A - Gas laser device - Google Patents

Abstract

PURPOSE:To prevent dew from condensing on the external surface of an oscillating tube and to remove dew if any condensing on it by a method wherein a temperature-air conditioner is accommodated in a hermetically sealed container covering the entirety of the oscillating tube. CONSTITUTION:At least the entirety of an oscillating tube 1 of a gas laser device, wherein an AC voltage is applied to an electrode 2 provided in close contact on the external surface of the oscillating tube 1, is accommodated, together with a temperature-air conditioner 10, in a hermetically sealed container 6. For example, when a device of this design is to be started with some dew condensing on the external surface of the oscillating tube 1, a heating core 5 is supplied with heat, a fan 4 is operated for the circulation of warm air in the closed space, for the evaporation of dew from and dryout of the external surface of the oscillating tube 1. The supply of heat to the heating core 5 is then stopped and a cooling core 3 is supplied with a coolant for the circulation of a cool wind, preventing the temperature in the closed space from rising too high owing to the laser device oscillation and operation.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a gas laser device that prevents misfire caused by dew condensation or the like occurring around electrodes provided on the outer surface of an oscillation tube.

(Prior art) Conventionally, as a silent discharge gas laser device, Japanese Patent Application Laid-Open No. 1983-1
As shown in Japanese Patent No. 38976, a gas laser device is known in which a high frequency AC voltage is applied to an electrode provided on the outer surface of an oscillation tube to cause laser oscillation.

In such a device, the relative permittivity Es of the oscillation tube made of an insulating material or the like is 5 to 20, and the relative permittivity Es of the dry gas such as air which is the external atmosphere! = i1, the resistance value R1 between the electrodes in the peripheral wall direction is much smaller than the resistance value R2 between the electrodes in the radial direction, as shown in Figure 3, so a normal discharge phenomenon can be obtained within the oscillation tube. It is.

(Problems to be Solved by the Invention) In the conventional device as described above, as shown in FIG. In some cases, water droplets that condensed together formed a film and formed a liquid layer.

Formation of such a liquid layer is caused by the resistance value R1 between the electrodes in the circumferential wall direction being smaller than the resistance value R2 between the electrodes in the radial direction since the dielectric constant Es of water is greater than 80, and an abnormal discharge ( This has the problem of not only preventing normal laser oscillation but also causing failure.

On the other hand, it is possible to prevent misfires by applying an insulating agent around the electrodes to form a thin insulating film, but this method is not expected to be very effective.

The present invention has been made in view of the above problems, and is aimed at preventing dew condensation on the outer surface of the oscillation tube of a gas laser device.
An object of the present invention is to provide a gas laser device that can remove water droplets when they are generated.

(Means and effects for solving the problem) In the present invention, a closed space including at least the entire oscillation tube is formed with a heat insulating wall, etc., and temperature conditioning/air conditioning equipment is provided that enables forced air cooling and heating of the inside of the closed space. By providing this, it is possible to prevent dew condensation on the outer surface of the oscillation tube and remove water droplets.

(Example) Hereinafter, an example of the present invention will be described in detail based on FIG. 1. In FIG. 1, 1 is an oscillation tube made of a dielectric material, 2 is an electrode provided on the outer surface of this oscillation tube, 9 is a high-frequency power source for applying a high-frequency AC voltage, and 15 is provided on one end surface of the oscillation tube. 16 is a partially transmitting mirror provided on the other end surface of the oscillation tube, 13 and 14 are air pipes provided at both ends of the oscillation tube, and 11 is a laser medium filled in the oscillation tube. A blower 12 for circulating gas is a heat exchanger for cooling the laser medium gas.

In the device configured as above, 6 is a sealed box that covers at least the entire oscillation tube 1, 10 is a temperature conditioning/air conditioning device provided in the sealed box, 3 is a cooling/heating core, and 5 is a heating/cooling unit. Core 4 is provided with a fan.

Next, the present invention will be explained in detail.

First, if there is dew condensation water etc. adhering to the outer surface of the oscillation tube 1 at the time of starting, heat is supplied to the heating core 5 and warm air is circulated in the closed space via the fan 4. Oscillator tube 1
The water droplets on the outer surface of the container are evaporated and dried.

Next, when the drying is completed and the gas laser device enters the oscillation/operation state, this closed space is heated and the ambient temperature rises, making it necessary to cool it down.

In this case, the supply of heat to the heating core 5 is stopped, refrigerant is supplied to the cooling core 3, and the fan 4 circulates cold air.

Switching the heat source supply and driving the fan are performed in the closed box 6.
It is activated by a temperature sensor installed inside.

(Not shown) Cooling water from a cooling device (chiller) attached to the laser device is used as the cold source, and an electric heater is used as the hot source.

However, it goes without saying that any form can be selected as the cold source and the hot source, and for example, it may be replaced with a heat pump system that can perform heating, cooling, and air blowing in the same device.

(Effects of the Invention) As explained above, the present invention particularly prevents misfire by preventing dew condensation occurring on the outer surface of the oscillation tube in an AC discharge gas laser device. This can prevent unstable operation and damage to equipment.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the gas laser device of the present invention, FIG. 2 is a block diagram of a conventional gas laser device, and FIG. 3 is a diagram showing the interelectrode resistance value in the gas laser device. 3... Cooling/heating core, 4... Fan 5... Heating/cooling core, 6... Sealed box 10... Temperature conditioning/air conditioning device

Claims (3)

[Claims] (1) In a gas laser device that applies an alternating current voltage to an electrode provided in close contact with the outer surface of an oscillation tube as an excitation means, a sealed box that covers at least the entire oscillation tube and a temperature controller provided in the sealed box are used.・Gas laser device consisting of air conditioner. (2) The gas laser device according to claim 1, wherein the electrode uses a plurality of straight conductor pieces or spiral strip-shaped conductor pieces. (3) The gas laser device according to claim 1, wherein the electrode is covered with an insulating material.