DARPA researchers demonstrate LWIR camera with five-micron pixels
Arlington, VA--Researchers at DRS Technologies (Merrimack, NH), working on the DARPA Advanced Wide FOV Architectures for Image Reconstruction and Exploitation (AWARE) program, have demonstrated the first longwave-infrared (LWIR) camera that has sensor pixels only five microns across (LWIR cameras are use, for example, as thermal imagers to detect humans at night).
This is the first IR camera that has pixels of no more than about half the size of the photons it detects. Each pixel is about one-sixth the area of existing state-of-the-art pixels, says DARPA. The pixels are configured in a 1280x720 focal-plane array (FPA), a relatively high resolution for an IR camera.
Related: Sofradir demos a video-quality 15-micron-pitch LWIR detector
Related: HgTe-HgCdTe superlattice photodetector has high response in LWIR
Smaller pixels mean smaller optical components and packaging without forfeiting sensitivity, resolution, or field of view. A higher density of pixels over a given area makes it easier to capture the photons from, and thus image, a target. The cumulative result is a smaller, lighter, and more portable LWIR camera.
Because the cost of an FPAs is proportional to its chip area, the new LWIR cameras may also be less expensive than current sensors (FPAs are processed on a given wafer size; the more FPAs that can be printed on a single wafer, the lower the cost per FPA). DARPA hopes that with appropriate optical adjustments, the advantages of smaller-pixel FPAs will find a home in a multitude of next-generation applications.
“DRS built three fully functional prototypes as part of this DARPA work,” said Nibir Dhar, DARPA program manager. “The cameras have been tested for various applications, including peering through particles in the air, which would be useful for helicopters landing in brownout conditions. We have found that the image is crisp and the performance of these FPAs is comparable to those with much larger pixel sizes.”
John Wallace | Senior Technical Editor (1998-2022)
John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.