Being the projection optical system which projects the image of the production mannered null 1st body of the device which uses the exposure device, and the said

摘要

A compact and high-performance projection optical system which can correct aberrations very satisfactorily while attaining an image side telecentricity over the whole exposure region and securing a sufficiently large numerical aperture (NA) and a wide exposure region and an aligner comprising the optical system. The projection optical system (PL) projects the image of a reticle (R) illuminated by an illumination optical apparatus (IS) onto a wafer (W). The projection optical system (PL) has NA-determining aperture diaphragms (AS1, AS2) at positions close to the pupil position in the optical system, and the aperture diaphragms (AS1, AS2) are so disposed as to become telecentric on the wafer (W) side. At least one of the aperture diaphragms (AS1, AS2) can change the size of its aperture and can move in the axial direction.