JPH03285376A - Excimer laser device - Google Patents

Abstract

PURPOSE:To safely discharge gas even if gas is leaked from a gas tube by installing the tube in a tube cover, connecting one end of the cover to a housing of a laser oscillator, and evacuating in the housing and the cover to reduced pressures. CONSTITUTION:Old gas in an oscillator tube 2 is first discharged by a discharge pump 10 at the time of starting an operation. Then, gas is then filled in the tube 2 through gas tubes 5-8. In this case, in order to normally fill gas of 2 to 3 atms in the tube 2, pressure of 4 atms or higher is applied to the tubes 5-8. Thus, there is a danger of gas leakage from the tubes 5-8, but even if gas is leaked from the tubes 5-8, the gas is leaked into a tube cover 12 reduced under pressure lower than that in the chamber, the chamber is not contaminated. Further, the leaked gas is immediately discharged out of the chamber from a duct 11 through the housing 3 of a laser oscillator 1. It is apprehended that the gas is leaked from the tube 2 during laser operating, but even in such a case, the leaked gas is discharged out of the chamber by the duct, there is no danger of leaking the gas into the chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an excimer laser device for industrial and medical use.

BACKGROUND OF THE INVENTION In recent years, excimer lasers have attracted much attention as a new industrial laser light source. Excimer lasers use a combination of rare gases such as krypton (Kr) and xenon (Xe) and halogen gases such as fluorine (F) and chlorine (CL') as laser media to produce wavelengths from 353 nm to 193 nm.
It is one of the ultraviolet lasers that can produce an oscillation line in a short wavelength range.Excimer laser devices can obtain large output in a short wavelength range compared to conventional laser devices, so they can be used for microfabrication, surgery, etc. It is expected to be a new light source in fields such as surgery.

Especially in the medical field, CO
While infrared lasers such as 2 laser and YAG laser perform incisions and hemostasis using thermal effects, excimer lasers can utilize photochemical effects due to high photon energy and have the potential to open up new fields of treatment. ing.

A conventional excimer laser device will be explained below.

FIG. 4 is a block diagram of a conventional excimer laser device.

In FIG. 4, 1 is a laser oscillator, 2 is an oscillation tube, 3 is a housing, 4 is a collecting pipe, 5 to 9 are gas piping for gas supply and exhaust, 10 is an exhaust pump, and 11 is a duct. In an excimer laser device, the oscillation tube 2 is usually filled with a mixture of laser medium gas and diluent gas. For example 24
Krypton fluoride (K r F
) In excimer lasers, krypton (
Kr) and fluorine (F), and helium (He) as a diluent gas.
＞, neon (Ne), etc. are used. Each time the laser device is operated, the oscillation tube 2 is filled with these gases at a pressure of several atmospheres. After a certain period of operation, the gas in the oscillation tube 2 is exhausted by the exhaust pump 10, and the mixed gas is replaced with a new one. Excimer laser devices have a problem in that the laser output decreases over time due to deterioration of the medium gas, so it is necessary to periodically replace the gas to maintain the output.

Problems to be Solved by the Invention However, in the conventional configuration described above, gas pressure higher than atmospheric pressure is applied to the oscillation tube and gas piping, so the room where the laser device is used is exposed to medium gas, especially toxic fluorine gas or chlorine gas. There was a problem of being exposed to the risk of accidents due to leakage.

Additionally, in order to prevent gas leakage from the oscillation tube, a duct is connected to the laser device housing that covers the oscillation tube, and the air inside the housing is exhausted to the outside to prevent gas leakage into the room.

The present invention solves the above-mentioned conventional problems, and aims to provide an excimer laser device that can safely discharge gas even if it leaks from a gas piping section.

Means for Solving the Problems To achieve this object, the excimer laser device of the present invention is equipped with a laser oscillator and a gas pipe for supplying a laser medium gas and a diluent gas to the laser oscillator. The piping cover is installed in the cover, one end of the piping cover is connected to the housing of the laser oscillator, and the inside of the laser oscillator housing and the inside of the piping cover are depressurized and exhausted.

Effect: With this configuration, even if there is a gas leak from the gas piping,
The pressure inside the pipe cover covering the gas pipes is reduced from indoors, so gas will not leak to the outside. Furthermore, since the leaked gas is immediately exhausted, the scope of contamination caused by the leaked gas can be kept to a minimum.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of an excimer laser device in one embodiment of the present invention. Note that the same parts as in the conventional example shown in FIG. 4 are given the same reference numerals, and detailed explanations are omitted. 12 is a piping cover that covers the gas piping 5 to 9. Gas pipes 5 to 8 are connected to a collecting pipe 4 in the laser oscillator 1 and supply medium gas and dilution gas to the oscillation pipe 2. Also exhaust pump 10
is used for the purpose of discharging the gas filled in the oscillation tube 2 via the gas pipe 9. The piping cover 12 covers the gas piping 5~
8, and its end is connected to the housing 3 of the laser oscillator 1. The air inside the piping cover 12 and the housing 3 is continuously discharged to the outside through the duct 11, and the internal pressure thereof is below atmospheric pressure.

Next, gas flow in an excimer laser device according to an embodiment of the present invention will be explained. When starting operation, first
The old gas in the oscillation tube 2 is exhausted by the exhaust pump 10. Subsequently, the oscillation tube 2 is filled with gas through the gas pipes 5 to 8. At this time, since the oscillation tube 2 is normally filled with gas at 2 to 3 atmospheres, a pressure of 4 atmospheres or more is applied to the gas pipes 5 to 8. Therefore, there is a risk of gas leakage from the gas pipes 5 to 8, but even if there is a leak from the gas pipes 5 to 8, the gas will be transferred to the pipe cabinet 12, which is depressurized from the room.
Since it leaks into the room, it does not contaminate the room. Moreover, the leaked gas immediately passes through the housing 3 of the laser oscillator 1 and is discharged to the outside from the duct 11. There is a concern that gas may leak from the oscillation tube 2 while the laser device is in operation, but even in such a case, the leaked gas is exhausted to the outside by the duct 11, so there is no danger of it leaking into the room.

Further, FIG. 2 is a sectional view showing a method of connecting the piping cover 12 and the laser oscillator 1. Gas pipes 5 to 8 are connecting pipes 13
It is connected to the collector pipe 4 in the laser oscillator 1 by. The piping cover 12 is connected to the casing 3 of the laser oscillator 1, and ventilation holes 14 are provided at several places on the casing 3 so that the air inside the piping cover 12 can flow into the casing 3. . With this device, leaked gas inside the housing 3 and inside the piping cover 12 can be immediately discharged to the outside through the duct 11.

Moreover, FIG. 3 is a block diagram of another embodiment of the present invention. In the embodiment shown in FIG. 3, of the gas pipes 5 to 9, only the pipe 5 that supplies fluorine (F) or chlorine (Ce), which is a toxic gas, is provided with a pipe cover 12.
There is no difference in function from configuration 1 of the excimer laser device explained in FIG. In this embodiment, the piping cover 1
By limiting the number of gas pipes that can be accommodated within 2, maintenance and inspection of the gas pipes 5 to 9 is facilitated.

Note that even if the method of connecting the piping cover 12 and the housing 3 or the method of exhausting the inside of the piping cover 12 and the inside of the housing 3 is other than that described in this embodiment, the insides of both can be depressurized and evacuated. However, any structure may be used as long as the leaked gas can be discharged outside.

As described in the detailed description of the invention, by providing a piping cover over the gas piping and depressurizing and exhausting the inside of the piping cover, there is no leakage of toxic fluorine (F) gas or chlorine (Ce) gas into the room, making it suitable for medical treatment. This makes it possible to realize an extremely safe excimer laser device for industrial and processing purposes.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram of an excimer laser device according to an embodiment of the present invention, Fig. 2 is a sectional view showing a connection method of the excimer laser device, and Fig. 3 is a schematic diagram of another embodiment of the excimer laser device. FIG. 4 is a schematic diagram of a conventional excimer laser device.

Claims (1)

[Claims] The method includes a laser oscillator and a gas pipe for supplying a laser medium gas and a diluent gas to the laser oscillator, the gas pipe is arranged in a piping cover, and one end of the piping cover is connected to a housing of the laser oscillator. an excimer laser device that evacuates the interior of the laser oscillator housing and the piping cover;