Patent ID: 7301646

Claim:
A device for the determination of imaging errors of an optical imaging system using a radiation-superposition measuring technique which operates with lateral phase offset, comprising: an optical element arranged on the object side of the imaging system, having a first periodic structure on the object side with a predetermined periodicity direction, an optical element arranged on the image side of the imaging system, having a second periodic structure on the image side with a periodicity direction corresponding to the first periodic structure, an image of the first periodic structure together with the second periodic structure forming an interference or superposition pattern, and a detector to detect the interference or superposition pattern, wherein at least one of the first and second periodic structures contains at least three periodic substructures, which are arranged offset relative to one another by a predetermined phase offset in the periodicity direction, and the detector has a plurality of detector elements, the number of which is matched to the number of substructures or which respectively have a number of detector surfaces for a predetermined aberration determination.