| 摘要 |
PROBLEM TO BE SOLVED: To restrain the lowering of performance while preventing contamination with organic materials and discharged carbons by introducing oxygen gas into a vacuum container from which X-rays are taken out from plasma formed by a pulse laser beam, and irradiating an optical element or an optical member with ultraviolet rays or light having a short wavelength. SOLUTION: In a vacuum container 100 formed at a low degree of vacuum by a rotary pump 116, the pulse laser light 101 introduced through a focus lens 102 and a window 103 is irradiated to a target member 104 made of polyester or the like so as to form the plasma 105. X-ray 106 is taken out of the plasma 105, and led out to other X-ray optical system through a visible light cutting and X-ray transmitting film 107 such as a Be film. After the predetermined time is passed, the oxygen gas is introduced from a introducing port 115, and while the ultraviolet rays generated in an ultraviolet rays lamp chamber 108 provided with an Xe excimer lamp 109 is radiated to an optical member inside of the container. With this structure, organic contaminants adhered by the ozone generated from the oxygen gas and the ultraviolet rays can be easily decomposed for gasification so as to be eliminated. |
