| 摘要 |
PURPOSE:To facilitate cooling of metal electrodes and so forth sufficiently by a method wherein the metal electrodes are attached to the outer wall of a discharge region forming member made of dielectric and the discharge region forming member is provided in a resonance part gas feeding tube along the longitudinal direction of the tube. CONSTITUTION:A partial reflection mirror 11 and a total reflection mirror 12 are attached to one end and the other end of the longitudinal direction of a cylindrical resonance part gas feeding tube 10 so as to face each other. A discharge region forming member such as a discharge tube 13 made of dielectric is provided in the resonance part gas feeding tube 10 along its longitudinal direction to form a tubular space 14 between the discharge tube 13 and the resonance part gas feeding tube 10. A pair of metal electrodes 15 and 15 are attached to the outer wall of the discharge tube 13 along its longitudinal direction so as to face each other. A pair of the electrodes 15 and 15 are connected to a radio frequency electric source 16. Both longitudinal ends of the resonance part gas feeding tube 10 are linked with a gas feeding tube 17. A pair of heat exchangers 18 and 18 and a root blower 19 are provided in the middle of the gas feeding tube 17 to circulate laser medium gas as shown by arrow marks 20. With this constitution, even if a discharge injection power is large, the temperatures of the discharge tube 13 and the electrodes 15 are maintained relatively low and a spark discharge is not induced so that the laser beam oscillation output can be large. |
