| 摘要 |
PURPOSE:To give efficient and effectual cooling action without losing cooling operation as refrigerant by cooling a partition window on the low temperature side, a reflector, and a nozzle, which become higher in temperature in this order and by cooling from the side of the partition window and the reflector in significance order in regard to accuracy of irradiating positions. CONSTITUTION:Auxiliary gas for working supplied from the side of a gas supply tube 44 is blown off from a gas supply/blow-off parts 40, 41 toward the inside of the compartment window 29 and the reflecting surface of a parabolic mirror 15, passes through the inner part of the nozzle 7 and is injected to a working/treating part through a nozzle tip hole 36 and from between chips 37. By ejecting operation of auxiliary gas for working, deposits such as dust, etc., stuck to the inside of the compartment window 29 are blown off and removed and the reflecting surface of the parabolic mirror 15 and deposition of dust, etc., too, can be prevented effectively. Further, the inside of the compartment window 29 and the reflecting surface of the parabolic mirror 15 which are heated by the adsorption of laser beam LB can be cooled by the flow of the auxiliary gas for working to give an effective cooling function. |
