Dec 1 2010
A research group led by CEA-Leti has developed a new imaging array with high thermal resolution. The new mercury cadmium telluride (MCT) detector functions at 8 to 10 µm in the long-infrared range and is ideal for security and defense applications.
The 320 x 256-pixel camera provides a resolution of 1-2 mK at ambient temperatures with a frame rate of 25 to 50 Hz. In order to attain the operating characteristics, the CEA-Leti researchers developed a new reading circuit that offers analog-to-digital conversion at every pixel of the MCT array. The reading circuit is based on the 0.18 µm CMOS die. The camera features an operational temperature of 77 K with a 25-µm pixel pitch.
The imaging array will allow highly sensitive thermography applications in the defense and security applications. The LWIR area is spectroscopically crucial, with various chemicals such as sulfur hexafluoride, ammonia, and ethanol absorbing in the 8 to 10 µm band. The explosive triacetone triperoxide and the nerve agent sarin also absorb in the LWIR region.
The new camera technology is a result of the collaboration between an aerospace firm Onera; the Direction Générale pour l'Armement (DGA); France’s defense procurement agency; a manufacturer of MCT detector, Sofradir; and CEA-Leti.