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NASA NTRS · 20180007646

Compact LWIR Polarimeter for Cirrus Ice Properties

Hart, Kira A.·Chipman, Russel A.·Wu, Dong L.
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Abstract

A miniaturized long-wave InfraRed (LWIR) spectro-polarimeter is being developed as a prototype for the Compact Submm-Wave and LWIR Polarimeters (SWIRP) project. The polarimeter in development is a compact (20x20x40 cm) conical-scan instrument to measure the polarimetric radiation from ice cloud scattering at mm-submm (220 and 680 GHz) and IR (8.6, 11, and 12 m) bands. The LWIR polarimeter will provide a series of polarization measurements across the 8.5 - 12.5 micron band, measuring the full set of linear Stokes parameters (I, Q, U) as a function of wavelength. The spectro-polarimeter uses a combination of birefringent crystals, a Wollaston prism, a diraction grating, and an uncooled microbolometer array to measure both the degree and angle of linear polarization across the spectral bandwidth by modulating the polarization ux in wavelength with a high order retarder.

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Hart, Kira A., Chipman, Russel A., Wu, Dong L.. 2018-05-14. Compact LWIR Polarimeter for Cirrus Ice Properties. https://ntrs.nasa.gov/citations/20180007646

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