Patent ID: 6304330
Filing Date: 2001-10-16
Classification: G01B,G01J,G01N

Abstract:
Apparatus for splitting a wavefront, said apparatus comprising:a wavefront-splitting element for:receiving a wavefront including a reference wavefront and an object wavefront said reference wavefront and said object wavefront being orthogonally polarized;splitting said wavefront into a plurality of sub-wavefronts such that each of said said sub-wavefronts is substantially contiguous with at least one other said sub-wavefront, wavefront-splitting element splitting said wavefront such that each of said sub-wavefront includes said reference wavefront and said object wavefront;providing said plurality of sub-wavefronts;a phase-shifting interference element for:receiving said plurality of sub-wavefronts;discretely shifting the relative phase between said reference wavefront and said object wavefront of said sub-wavefronts to yield a respective plurality of phase-shifted sub-wavefronts;interfering said reference and said object wavefronts of said phase-shifted sub-wavefronts to yield a respective plurality of phase-shifted interferograms, said phase-shifted interferograms; andproviding said plurality of phase-shifted interferograms; anda sensing element for receiving said phase-shifted interferograms from said phase-shifting interference element.