| 摘要 |
PURPOSE:To prevent preionization from deteriorating at the time of high repetition operation by surrounding the main section of a preionizing means by means of a translucent communicating pipe and moving gas in the communicating pipe at high speed thereby preventing instable main discharge or deterioration of optical window due to sputtering particles or various impurities produced through discharge. CONSTITUTION:The laser device 1 comprises a pair of main discharge electrodes 3A, 3B and a preionizing means 4 disposed in parallel therewith, both of which are contained in a gas container 2. The preionizing means 4 comprises a plurality of pairs of pin gap electrodes 5A, 5a, 5B,... disposed in a translucent communication pipe 6. Preionization discharge gas 7 in the communication pipe 6 is circulated at high speed by means of an external gas circulation fan 9 while being isolated from laser medium 8 present at the main discharge section. Gas circulation fans 14, 9 at the main discharge section and preionization means exhibit low thermal. insulation head-high gas flow rate characteristics and high thermal insulation head-low gas flow rate characteristics, respectively and relatively. |
