The University of Arizona

North Carolina State University

Michael W Kudenov

Michael James Escuti

Edward Allen DeHoog

James T Schwiegerling

Eustace Dereniak

Kazuhiko Oka

Haitao Luo

Polarization based channeled images are optically demodulated to produce directly viewable images. A channeled image flux is converted to an unpolarized flux by a phosphor or other sensor, and the resulting converted flux is demodulated by modulating at a spatial frequency corresponding to a modulating frequency of the channeled image flux. After modulation, the converted flux is spatially filtered to remove or attenuate portions associated with the modulation frequency and harmonics thereof. The resulting baseband flux is then imaged by direct viewing, projection, or using an image sensor and a display.

Snapshot spatial heterodyne imaging polarimetry

White-light snapshot channeled linear imaging (CLI) polarimeters include polarization gratings (PGs) configured to produce a compensated shear between portions of an input light flux in first and second polarization states. The disclosed CLI polarimeters can measure a 2-dimensional distribution of linear Stokes polarization parameters by incorporating two identical PGs placed in series along an optical axis. In some examples, CLI polarimeters are configured to produce linear (S, S, and S) and complete (S, S, Sand S) channeled Stokes images.

White light achromatic grating imaging polarimeter

Snapshot imaging polarimeters comprise Sagnac interferometers that include diffraction gratings situated to produce shear between counter-propagating optical fluxes produced by a polarizing beam splitter. The counter-propagating, sheared optical fluxes are focused onto a focal plane array to produce fringe patterns. The fringe patterns correspond to a scene polarization distribution modulated onto a spatial carrier frequency associated with a diffraction order. Multi-blazed gratings can be used so that modulations at a plurality of spatial frequencies are produced, with each spatial frequency corresponding to a spectral component of an input optical flux. Modulated fringe patterns can be demodulated to obtain scene Stokes parameter distributions.

White light Sagnac interferometer polarimeters

Snapshot imaging Fourier transform spectrometers include a lens array that produces sub-images that are directed through a birefringent interferometer in orthogonal polarization eigenstates that acquire an optical path difference. Interference patterns based on this OPD can be Fourier transformed to obtain a spectral image. In some examples, polarizing gratings provide a spatial heterodyne frequency and offset the spectra.

Ultra-compact snapshot imaging fourier transform spectrometer

An imaging polarimeter optics unit comprising: a first polarization-sensitive beam-splitter optic, a retarder, a second polarization-sensitive beam-splitter optic, and an analyzer, through which input light passes in sequence, wherein the retarder and polarization-sensitive beam-splitters cause the input light to have optical components that provide different information about the state of polarization of the input beam is provided.

Growing community of inventors

Tucson, AZ, United States of America

Michael W Kudenov