"Polarimetric Spectral Intensity Modulation (P-SIM): Enabling simultaneous hyperspectral and polarimetric imaging," F.J. Iannarilli, S.H. Jones, H.E. Scott, and P. Kebabian, Proc. SPIE 3698 (1999).
We introduce the method of Polarimetric Spectral Intensity Modulation (P-SIM) and discuss how it enables a new robust class of hyperspectral polarimetric imaging sensors. P-SIM was invented by one of us (P. Kebabian) and has been submitted for patent. We are presently building a sensor, dubbed the IR Polarimetric HyperSpectral Imager (IRPHSI) which implements the P-SIM concept. P-SIM employs a novel and robust optical multiplexing scheme that enables simultaneous measurement of spectral and full elliptical polarimetric image content, employing a single focal plane detector and conventional optics, and eliminating moving parts and difficult alignment issues. The technique is equally viable across the visible through long-wave infrared bands. The P-SIM concept constitutes a breakthrough for the inclusion of polarimetry in optical hyperspectral imaging. To date, even single-band polarimeter designs for remote sensing are compromised due to their lack of spatiotemporal measurement registration, inapplicability to marginally resolved scene elements, costly optical configurations, or polarimetric ambiguity from too few "channels". Polarimetric imaging from a moving platform (i.e., moving field of regard) or against moving targets rules out the standard methods of time-sequential polarimetry via rotation of a polarizer or waveplate. P-SIM eliminates these limitations while additionally extending polarimetry into the spectral imaging domain.