Patent ID: 7268890

Claim:
A device for wavefront measurement of an optical imaging system, comprising: a wavefront generating unit arranged on the object side of the imaging system to be measured and comprises an optical element with an object-side periodic structure and a light source unit for illuminating the object-side periodic structure with the aid of a measuring radiation, and a detector unit arranged on the image side of the imaging system to be measured and comprises an optical element with an image-side periodic structure and a detector element for detecting an overlay pattern of the imaged object-side periodic structure and image-side periodic structure, wherein the wavefront generating unit is designed to restrict the angular spectrum of the measuring radiation emanating from a field point, the design being such that at least the measuring radiation emanating from a first and a second field point respectively illuminates only a subregion of a pupil plane of the optical imaging system, and wherein the pupil subregion belonging to the first field point at most partially overlaps the pupil subregion belonging to the second field point.