| 摘要 |
PURPOSE:To enable a total reflection mirror to be set easily by modification of a laser gas by forming each dielectric body multi-layer film which entirely reflects different laser lights on both surfaces with the total reflection mirror constituting a resonator as an external mirror. CONSTITUTION:A dielectric multi-layer film 9 reflecting laser light of ArF (193nm) by 100% and a dielectric multi-layer film 10 reflecting laser light of KrF (248nm) by 100% are formed on one surface of an external total reflection mirror 8 and on the other surface. When ArF or KrF gas is filled into a discharge container 1, the mirror 8 is installed so that each multi-layer film 9 or 10 is used. |
