APPARATUS AND METHOD FOR IN SITU AND EX SITU MEASUREMENTS OF OPTICAL SYSTEM FLARE

摘要

Apparatus and methods for in situ and ex situ measurements of spatial profiles of the modulus of the complex amplitude and intensity of flare generated by an optical system. Thein situ and ex situ measurements comprise interferometric and non-interferometric measurements that use an array of diffraction sites simultaneously located in an object plane of the optical system to increase signals related to measured properties of flare in a conjugate image plane. The diffraction sites generate diffracted beams with randomized relative phases. In general, the interferometric profile measurements employ phase-shifting point-diffraction interferometry to generate a topographical interference signal and the non-interferometric measurements are based on flare related signals other than topographic interference signals. The topographical interference signal and flare related signals are generated by a detector either as an electrical interference signal or electrical flare related signals or as corresponding exposure induced changes in a recording medium.