U. S. Army NVESD MWIR Polarization Research for Ground Targets

摘要

Previous infrared polarization imaging research has shown manmade objects to be sources of emitted and reflected polarized radiation while light from natural backgrounds is predominantly unpolarized. The prior work underscored the dramatic improvements in signal to clutter ratio that could be achieved in a typical target acquisition scenario using polarization sensing techniques. The U. S. Army Night Vision and Electronic Sensors Directorate has developed complete Stokes imaging polarimeters in an effort to investigate polarization phenomenology and to quantify expected improvements to target acquisition and mine detection. While polarization due to reflection in the visible spectrum has been studied more and is better understood, in this paper we concentrate on polarization due to reflection and emission in the infrared since we are interested in technology with tactical utility and thus twenty- four hour capability. After a brief review of IR polarization phenomenology and a short summary of previous work this paper will review the design and calibration of one of our infrared polarization cameras. Example phenomenology studies of MWIR polarization from surface scattered land mines and from ground targets at tactically relevant ranges will be presented.