Patent ID: 7280184

Claim:
An adjusting method of an optical system that includes plural optical elements each having a multilayer film, said adjusting method comprising: a first measuring step of measuring, for each optical element, a phase distribution of an EUV light when the EUV light is reflected on the optical element, and a phase distribution of a light with a wavelength that is longer than that of the EUV light when the light with the wavelength is reflected on the optical element; a first finding step of finding, for each optical element, a difference between the phase distribution of the EUV light when the EUV light is reflected on the optical element and the phase distribution of the light with the wavelength when the light with the wavelength is reflected on the optical element; a second measuring step of measuring a phase distribution of the light with the wavelength when the light with the wavelength passes the optical system; a second finding step of finding a phase distribution of the EUV light if the EUV light passes the optical system based on the difference for each optical element found by the first finding step and the phase distribution measured by the second measuring step; and an adjusting step of adjusting at least one of a position and a posture of the optical element based on the phase distribution found by the second finding step.