BIREFRINGENT SPECTRAL DEMULTIPLEXER FOR HYPERSPECTRAL IMAGING

摘要

A birefringent spectral demultiplexer for hyperspectral imaging includes N birefringent beamsplitting stages arranged along a light propagation path, to produce 2^N mutually divergent output light beams. Each of the output light beams differs from every other one of the output light beams in polarization and/or spectral bandwidth. Each birefringent beamsplitting stage includes a retarder for modifying polarization of each light beam received by the birefringent beamsplitting stage, and a Wollaston prism for splitting each light beam into two orthogonally polarized and divergent light beams. The Wollaston prism has a beamsplitting interface arranged at an oblique angle to the light propagation path. The oblique angle of the beamsplitting interface of each Wollaston prism of the series, except for the first one, is smaller than the oblique angle of the beamsplitting interface of each preceding Wollaston prism. The demultiplexer may be configured to accept input light of any polarization.