Optically Registered Polarimetric Imaging LWIR Sensor

The Department of the Army has identified long wave infrared (LWIR) polarimetry as a means for enhanced detail of human imagery for facial recognition. In addition, polarimetry has been shown to improve image contrast, detect anthropomorphic objects in high clutter scenes, and provide 3D shape information. However, many polarimeters operate using rotating polarization filters or retarders, which result in false polarization signatures in scenes containing movement.For non-cooperative targets, being able to capture the polarization signature of a moving target is essential.In order for the sensor to be operationally useful, the polarization signature must be measured in a single frame.This is typically accomplished using a microgrid polarizer array, in which each pixel has a polarization filter, much like the Bayer filters used on color cameras.However, features that are subpixel can still result in false polarization signatures.IERUS engineers have developed a micro-optic that can optically register the four pixels used to measure the polarization signature.The IERUS approach will integrate the optical registration micro-optic and microgrid polarizer with a cooled dual band IR camera to build the polarimetric sensor and associated processing hardware.