| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an illumination optical system capable of adjusting the pupil intensity distribution, while suppressing the loss in optical quantity to a low level. <P>SOLUTION: The illumination optical system for illuminating surfaces (M, W) to be illuminated based on light from a light source (1) is provided with a pupil intensity distribution forming means (3-10) for forming a first optical intensity distribution on a first region of an illumination pupil and forming a second optical intensity distribution on a second region spaced from the first region. The pupil intensity distribution forming means has intensity ratio variable means (3, 4, 5) for varying the intensity ratio of the first light intensity distribution and the second light intensity distribution. The intensity ratio variable means has a light flux separating means (3) for separating an incident light flux into a plurality of light fluxes, and a diffractive optical member (5) for forming the first optical intensity distribution and the second optical intensity distribution, on the basis of the plurality of light fluxes separated by the light flux separating member, and is configured so that the light flux separating member and the diffractive optical member can relatively rotate around an optical axis (AX). <P>COPYRIGHT: (C)2009,JPO&INPIT |
