Snapshot Imaging Spectropolarimeter for the Long Wavelength Infrared

摘要

An extremely unique imaging system, that is capable of simultaneously recording both the spectral and polarimetric signatures of all the spatial locations/targets in a scene with just a single integration period of a camera, has been built for use in the long wavelength infrared, 8 to 12 microns. The system contains no moving parts and collects all of its data in a single snapshot. This snapshot capability makes it ideally suited for observing and characterizing quick events or fast moving objects without the associated scanning artifacts found in conventional imaging spectrometers and polarimeters. The rate at which you can record the temporal nature of a target's spectral and polarimetric signature is only limited by the frame rate and sensitivity of the camera detector. The imaging system is based on a combination of a Computed Tomographic Imaging Spectrometer (CTIS) and a channeled spectropolarimeter. Only three polarization elements need to be added to a CTIS system to incorporate channeled spectropolarimetery, but to understand how the entire spectropolarimeter system works we will first review the basic design and operating principles of the Computed Tomographic Imaging Spectrometer (CTIS).