| 摘要 |
PROBLEM TO BE SOLVED: To enable the constitution by combination of excimer optical components with an optimized wave front by measuring the liq. surface characteristics of each optical component of an excimer laser and selecting and combining the optical components, based thereon, to determine the shape of a laser wave front emitted from the excimer laser. SOLUTION: A laser beam 29 oscillating from an Ar double-wave laser 25 nearly at the oscillation wavelength of e.g. a KrF excimer laser is set to a reference light, the laser 29 passes through a diffusion lens 26m, beam splitter 28 and collimator lens 27 to magnify, and a plain wave 40 is incident on a reference mirror 31 from a half-mirror. If the wave front of the light passed through a prism 7 is an emission wave front 41, it is perpendicularly incident on a mirror 24 and reflected to pass reversely through the prism 7 to the reference mirror 31, resulting in a measured light having a wave front 42. An interference fringe 33 contg. wave front information after passing through an image- forming lens 35 is analyzed by an interferometer controller 38 to know the shape of the wave front 42 of the measured light. |
