Researchers develop infrared imaging system that increases resolution of LWIR cameras

Researchers at Northwestern University (Evanston, IL, USA) have created a new infrared camera based on Type-II InAs/GaSb superlattices that produces much higher resolution images than previous long wavelength infrared (LWIR) cameras. Created by Manijeh Razeghi, Walter P. Murphy Professor of Electrical Engineering and Computer Science, and researchers in the Center for Quantum Devices in the McCormick School of Engineering and Applied Science, the long wavelength infrared focal plane array camera provides a 16-fold increase in the number of pixels in the image.

The goal of the research is to offer a better alternative to existing LWIR cameras, which are used in everything from electrical inspections to security and nighttime surveillance. Current LWIR cameras are based on mercury cadmium telluride (MCT) materials, but the Type-II superlattice is mercury-free, more robust, and can be deposited with better uniformity. This will significantly increase yield and reduce camera cost once the technology goes commercial.

“Not only does it prove Type-II superlattices as a viable alternative to MCT, but also it widens the field of applications for infrared cameras,” Razeghi said. “The importance of this work is similar to that of the realization of megapixel visible cameras in the last decade, which shaped the world’s favor for digital cameras.”

Their results were recently published in the journal Applied Physics Letters, Volume 97, Issue 19, 193505 (2010).

Posted by Conard Holton
Vision Systems Design