Patent US 5,608,575

An edge emphasis type phase shift reticle is illuminated obliquely, and zeroth order diffraction light and first order diffraction light caused by a fine pattern of the reticle and having substantially the same intensity are incident and distributed on a pupil of a projection optical system, symmetrically with respect to a predetermined axis, whereby the fine pattern is imaged with use of the zeroth order diffraction light and first order diffraction light.