BEAM STEERING DEVICES INCLUDING STACKED LIQUID CRYSTAL POLARIZATION GRATINGS AND RELATED METHODS OF OPERATION

摘要

A beam steering apparatus includes a first beam steering stage and at least a second beam steering stage arranged in-line with the first beam steering stage. The first beam steering stage includes a first polarization grating comprising a uniaxial birefringent material having a first periodic director pattern, and the second beam steering stage includes a second polarization grating comprising a uniaxial birefringent material having a second periodic director pattern. In nonmechanical embodiments, a polarization selector may be arranged to provide a circularly polarized input beam incident on the first polarization grating. In mechanical embodiments, at least one of the first polarization grating and the second polarization grating may be operable to be independently rotated about an azimuth thereof. Related methods of operation are also discussed.