Patent ID: 8004692

Claim:
An optical apparatus comprising: a plurality of spatial phase modulators, said modulators each comprising a plurality of side-by-side regions, said regions having a transmissive medium respectively, said modulators being arranged to divide an optical beam into at least a plurality of first beam portions and a plurality of second beam portions by wavefront division, said apparatus being arranged to transmit said first and second beam portions through said regions simultaneously and respectively, said regions being arranged for producing predetermined phase shift on said first and second beam portions respectively; said apparatus arranged such that said modulators influence said first and second beam portions only once; isolation means for reducing crosstalk between one of said first and one of said second beam portions, said isolation means comprising a structure for separating one of said first beam portions and one of said second beam portions; interference means for producing optical interference among said first beam portions and among said second beam portions respectively; and a plurality of detectors for detecting a plurality of signals of said interference respectively.