INSTRUMENT EFFECTS IN POLARIZED INFRARED IMAGES

We describe three instrument effects that cause polarized infrared ima ges of a blackbody source to exhibit intriguing polarization dependenc e and image nonuniformity. The origins of these problems are reflectio n of background radiation from the wire-grid polarizer and frictional heating of the polarizer mount. Our model shows that the two surfaces of a wire-grid polarizer act like a partial polarizer-analyzer pair fo r reflected radiance. These effects must be considered carefully in ap plications such as polarimetric remote sensing, which require calibrat ion uncertainties less than 1%.