ARL Develops New Type of Thermal Imaging Camera

Researchers at the U.S. Army Research Laboratory (ARL), in collaboration with Polaris Sensor Technologies Inc., have developed a new type of thermal imaging camera that allows soldiers to see hidden objects that were previously undetectable.

Researchers demonstrate an example of human identification using conventional and polarimetric thermal cameras. The thermal polarimetric image allows for fine facial details to emerge. Courtesy of the U.S. Army Research Laboratory.

Kristan Gurton, an experimental physicist in the computational and information sciences directorate, and Sean Hu, an electronics engineer in the sensors and electron devices electorate, are leading the effort.

“Researchers have known for about 30 years that man-made objects emit thermal radiation that is partially polarized — for example, trucks, aircraft, buildings, vehicles, etc. — and that natural objects like grass, soil, trees, and bushes tend to emit thermal radiation that exhibits very little polarization,” Gurton said. “We have been developing, with the help of the private sector, a special type of thermal camera that can record imagery that is based solely on the polarization state of the light rather than the intensity.”

The team’s most recent discovery involves the ability to detect and identify specific human subjects during complete darkness.

“Prior to our research at ARL, the only way to view humans at night was to use conventional thermal imaging,” Gurton said. “Unfortunately, such imagery is plagued by a ghosting effect, in which detailed facial features required for human identification are lost. However, when polarization information is included in the thermal image, that is, a thermal polarimetric image, fine facial details emerge, which allows facial recognition algorithms to be applied.”

Gurton and the other researchers are actively working to miniaturize the camera platform and make the systems more affordable.