| 摘要 |
PURPOSE:To prevent leakage of gas from a gas discharger by supplying gas having slightly higher pressure than that of a gas laser medium which has no or little influence to human body to a space between an enclosure for surrounding an entire gas laser discharger and the laser discharger. CONSTITUTION:A gas supply unit 24 for supplying predetermined gas to a space 23 between a gas discharger 20 and an enclosure 21 of the discharger 20, is provided. Predetermined gases are alternately supplied by the unit 24 to a sealed vessel 26 and the space 23, and pressure of a gas laser medium in the vessel 26 is set to a predetermined pressure. On the other hand, the space 23 is set to a higher pressure than that in the vessel 26 such as 0.3-0.5atm higher than that. Here, the gas to be sealed in the enclosure 21 is gas which has no or less influence to a human body. Thus, leakage of the gas from the discharger 20 can be prevented. Even if the gas is leaked from the enclosure 21, influence to the human body can be prevented. |
