JPH1056221A - Gas laser oscillation device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a laser oscillation device that secures a stable laser output immediately after the start of operation after a long-term stop. SOLUTION: A gas supply / discharge control device 100 for setting a laser gas supply / discharge amount to a set ratio or more in a normal operation for at least a timer time setting or more immediately after the start of discharge,
A gas laser oscillation device that can obtain a stable laser output.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas laser oscillating device using gas discharge excitation.

[0002]

2. Description of the Related Art A conventional gas laser oscillator will be described with reference to FIG. The laser discharge tube 1 made of a dielectric is filled or circulated with a laser gas 2. Laser discharge tube 1
The high-voltage power supply 5 connected to the electrodes 3 and 4 provided on the periphery generates a discharge 6 in the laser discharge tube 1. The laser gas 2 is excited by the discharge 6 to generate a laser beam between the total reflection mirror 7 and the partially transmission type reflection mirror 8, and a part of the laser beam is output as a laser beam 9 through the partially transmission type reflection mirror 8. .

A laser gas discharge port 11 and a laser gas supply port 12 connected to a gas supply / discharge control device 10 are provided around the laser discharge tube 1, and a part of the laser gas degraded by the discharge 6 is discharged. Exit 11
It is controlled so that a new laser gas that is constantly discharged and equal in amount to the discharged laser gas is always supplied from the laser gas supply port 12.

However, in order to perform stable discharge and obtain a stable laser output, it is necessary for the gas laser oscillation device to prevent impurities from entering the laser gas from the outside atmosphere as much as possible. Therefore, the gas laser oscillation device usually has a sealed structure that is isolated from the outside atmosphere.

However, it is impossible to achieve a completely hermetic structure due to the structure, and minute impurity particles such as water molecules enter a gas system from the air through a very small gap such as a joint between parts. Inevitable. However, during normal operation, a constant amount of laser gas is constantly replaced by the gas supply / emission control device 10, and even small impurity particles that have entered the gas system are discharged outside the gas system.
This is a level that does not matter at all.

[0006]

When the gas laser oscillation device is stopped for a long period of time, impurity particles, especially water molecules, which have entered the gas circulation system adsorb on the inner wall of the gas circulation system and accumulate. Is done. When the water molecules adsorbed and accumulated restarted operation and discharge after a long-term shutdown,
The heat of the discharge discharges all at once into the gas circulation path.

As a result, immediately after the start of the discharge, a large amount of water molecules are mixed in the laser gas, the discharge becomes unstable, and the laser output is reduced.

FIG. 7 shows the laser output immediately after the start of operation when the gas laser oscillation device is stopped for a long period of time, and it takes 15 to 20 minutes for the laser output to stabilize after the start of operation. I understand. Therefore, when the gas laser oscillation device is used after being stopped for a long time, a warm-up for 15 to 20 minutes is required, and there is a problem that the device cannot be used during that time.

In order to solve the above problem, it is conceivable to increase the supply and discharge amount of the laser gas controlled by the gas supply and discharge control device 10. However, the supply and discharge amount of the laser gas is always increased as compared with the conventional one. Attempting to secure a large amount increases the consumption of the laser gas and greatly increases the running cost, so that there is little merit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and has as its object to provide a gas laser oscillator capable of securing a stable laser output immediately after the start of operation even after a long-term stop.

[0011]

In order to achieve the above object, a gas laser oscillator according to the present invention comprises a laser discharge tube filled with a laser gas, a high-voltage power supply for supplying discharge energy to the laser gas, and a laser discharger. A gas laser oscillation device having a laser gas outlet for discharging a laser gas in a tube, and a laser gas supply port for supplying a new laser gas into a laser discharge tube, and a timer for receiving and counting a discharge start signal from a high voltage power supply, A gas supply / discharge control device is provided which makes the laser gas supply / discharge amount equal to or higher than the set ratio in the normal operation for at least the set time of the timer immediately after the start of the discharge.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With the above configuration, the gas laser oscillation device of the present invention allows the water molecules adsorbed and accumulated on the inner wall in the gas circulation path to be discharged when the operation and the discharge are started again after a long term stop. The heat is released into the gas circulation system at once. That is, by increasing the supply and discharge amount of the laser gas to 5 times or more of that in the normal operation for 5 minutes or more immediately after the start of the discharge, water molecules discharged into the gas circulation system can be removed from the gas system in a short time. Things.

At this time, since a large amount of water molecules are mixed in the laser gas, the laser output is supposed to be reduced, but the supply and discharge of the laser gas is temporarily increased. , A stable laser output can be obtained.

Further, since water molecules can be discharged to the outside of the gas circulation system in a short period of time, the temporarily increased supply and discharge amount of the laser gas can be immediately returned to the level of the normal operation state, and the laser gas consumption is reduced. Can be suppressed very slightly. An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, the difference from the conventional gas laser oscillation device is that a power supply device 50 and a gas supply / discharge control device 10 are provided.
0 is connected to the high voltage power supply 50 by the signal line 14.
When a high DC voltage is applied, a signal notifying the start of discharge is output to the gas supply / discharge device 100. The gas supply / emission control device 100
Is provided with a timer 13, and this timer 13
Receiving a discharge start signal from the high voltage power supply device 50, counting is started, and when the count reaches a set time, a signal is output from the timer 13 to the gas supply / discharge control device 100.

Next, the operation procedure of the gas supply / discharge control device 100 will be described with reference to the flowchart of FIG.

After the start of operation, the gas supply / emission control device 100
Performs the supply and discharge of the laser gas at the normal operation level (step S1). The discharge start signal from the power supply 50 is OF
During F (NO in step S2), the flowchart repeats this loop.

Here, when a discharge start signal is input from the power supply device 50 (YES in step S2), the gas supply / discharge control device 100 increases the supply / discharge amount of the laser gas to five times that in normal operation (step S3). ).

Next, the timer 13 receives the discharge start signal from the power supply device 50, and is reset (step S
4) Start counting (step S5). When the count of the timer 13 reaches the set time of 5 minutes (step S6
Then, the gas supply / discharge control device 100 returns the supply / discharge amount of the laser gas to the normal operation level (Step S).
7).

By the above operation, the supply amount of the laser gas can be increased five times as much as that in the normal operation only for 5 minutes immediately after the start of the discharge.

The point here is to minimize the consumption of the laser gas as much as possible to achieve the maximum effect. In this regard, an explanation will be given on the optimum value of the increase rate of the supply / discharge amount of the laser gas and the set time of the timer. FIG. 3 is a characteristic diagram showing a relationship between a laser gas supply / discharge amount and a laser output immediately after starting operation after a long-term stop.

From FIG. 3, it can be seen that in order to obtain a stable laser output immediately after the start of operation, it is necessary to supply and discharge the laser gas at least five times or more that in the normal operation.

FIG. 4 shows the operation after a long term stop.
FIG. 9 is a characteristic diagram illustrating a relationship between a timer set time (minutes) and a laser output immediately after the timer reaches a set time, that is, immediately after the laser gas supply / discharge amount returns to a normal operation level.
From this characteristic diagram, it is understood that the timer setting time is required to be 5 minutes or more.

Therefore, according to the present embodiment, a stable laser output can be ensured by setting the supply and discharge amount of the laser gas to at least five times the normal operation time for at least five minutes immediately after the start of the discharge.

FIG. 5 shows the effect of the embodiment of the present invention, and shows the laser output and the laser gas supply / discharge amount immediately after the start of operation after a long-term stop. Thus, in this embodiment, it is understood that a stable laser is obtained immediately after the start of operation. Further, the supply and discharge amount of the laser gas is five times the amount of the normal operation only for the first 5 minutes, and returns to the level of the normal operation after 5 minutes, so that the consumption of the laser gas increases, that is, the running cost also increases. Can be minimized.

[0026]

According to the present invention, a timer for receiving and counting a discharge start signal from a high-voltage power supply device, and setting a supply and discharge amount of a laser gas during a normal operation for at least a timer set time immediately after the start of the operation. A gas supply / discharge control device that doubles or more the gas supply / discharge control device is provided, and has an excellent effect of obtaining a gas laser oscillation device capable of securing a stable laser beam output immediately after the start of operation after a long-term shutdown.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of a gas laser oscillation device according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation procedure of the gas supply / discharge device in the embodiment.

FIG. 3 is a characteristic diagram showing a relationship between a laser gas supply / discharge amount and a laser output immediately after starting operation after a long-term stop.

FIG. 4 is a characteristic diagram showing a relationship between a timer setting time and a laser output immediately after a laser gas supply / discharge amount returns to a normal operation level.

FIG. 5 is a characteristic diagram showing a laser output and a laser gas supply / discharge amount immediately after the start of operation after a long term stoppage in the embodiment.

FIG. 6 is a schematic block diagram of a conventional gas laser oscillation device.

FIG. 7 is a characteristic diagram showing a laser output immediately after the start of operation after a long-term stop in the conventional example.

[Explanation of symbols]

 13 timer 14 signal line 50 high-voltage power supply device 100 gas supply / discharge control device

Claims (1)

[Claims] 1. A laser discharge tube filled with a laser gas, a high-voltage power supply for supplying discharge energy to the laser gas, a laser gas outlet for discharging the laser gas in the laser discharge tube, and supplying a new laser gas into the laser discharge tube. A gas laser oscillation device having a laser gas supply port, and a timer for receiving and counting a discharge start signal from a high voltage power supply device, and a laser gas supply / discharge amount during a normal operation for at least a timer set time immediately after the start of the discharge. A gas laser oscillation device provided with a gas supply / discharge control device that makes the ratio equal to or higher than the set ratio.