Patent ID: 6559952
Filing Date: 2003-05-06
Classification: G01B,G03F

Abstract:
A system for interferometric distortion measurements that defines an optical path, said system comprising:(a) a test optic with an extended field of view; (b) a source of electromagnetic radiation in the optical path; (c) an object-plane pinhole array comprising a plurality of object pinholes with known positions located between the test optic region and the source of electromagnetic radiation whereby energy passing through any one of the plurality of object pinholes is spatially coherent; (d) a beam divider in the optical path for dividing electromagnetic radiation from the source into a reference beam and a test beam; (e) an image-plane mask array that is positioned in the image plane of the test optic wherein the image-plane mask array comprises a plurality of test windows and corresponding reference pinholes of known positions, wherein the positions of the plurality of object pinholes in the object-plane pinhole array register with those of the plurality of test windows in image-plane mask array accounting for possible optic demagnification; and (f) means for directing electromagnetic radiation from the source of electromagnetic radiation into a first object pinhole of the object-plane pinhole array to thereby create a first corresponding test-beam image on the image-plane mask array.