Patent ID: 6859264

Claim:
A projection exposure apparatus comprising: a projection optical system arranged to project a pattern onto a substrate; a holding portion arranged to hold an optical element which emits light toward said projection optical system; a mask having a transmission portion and being disposed on or near a plane of an image of said optical element formed by said projection optical system; an actuator arranged to drive said mask along the plane of the image of said optical element; a measurement device arranged to measure an intensity of light while said mask is driven, the light emerging from said optical element, and passing through said projection optical system and the transmission portion of said mask, said measurement device including a measurement surface positioned at a plane spaced apart from said mask enough to separately detect respective rays emerging from plural points of a pupil plane of said projection optical system and passing through the transmission portion; and a device arranged to calculate aberration of said projection optical system on the basis of a measurement result of said measurement device.