Patent ID: 6104472
Filing Date: 2000-08-15
Classification: G03F

Abstract:
A projection exposure apparatus, comprising:a projection optical system for projecting a pattern of a mask onto a substrate, said projection optical system comprising a pair of aspherical members, at least one of which is displaceable in a direction orthogonal to an optical axis of said projection optical system, said pair of aspherical members having their aspherical surfaces disposed opposed to and close to each other, the aspherical surfaces having shapes which are mated with each other when placed in a particular positional relation,wherein (i) said aspherical members have aspherical surface shapes which are determined so that an optical characteristic of said aspherical members as a unit changes with a change in positional relationship between the aspherical surfaces of said aspherical members with respect to the orthogonal direction, (ii) an optical characteristic of said projection optical system is adjustable in response to displacement of said at least one of said aspherical members in the direction orthogonal to the optical axis and (iii) when said pair of aspherical members shifts in opposite directions, along the direction orthogonal to the optical axis and by the same amount, the positional relationship between the aspherical surfaces changes.