Sofradir, a manufacturer of advanced infrared detectors, and Onera, a centre of excellence for aerospace and defence research, has released an infrared (IR) detector with integrated fisheye optics.
The detector, based on Sofradir's Mercury Cadmium Telluride (MCT/HgCdTe) technology, features built-in 360° imaging. Previously, systems could only offer 360° imaging by using separate optical components.
The product will help producers of missile warning systems reduce the size of the associated optical sensors and also make them more robust.
The direct integration of 360° imaging lenses into the IR detector offers several benefits. First, the number of optical components is reduced. As a result, the camera's optical transmission is increased. This, in turn, improves the camera's sensitivity, a key feature in the performance of IR cameras.
Secondly, stray light is kept to a minimum. The ability to minimise stray light means that the thermal response and the background current are more stable. This extra stability reduces the need to correct non-uniformity, a weakness that occurs in standard IR cameras.
Missile warning systems are used on selected aircraft to notify the pilot of threats and to trigger the aircraft's countermeasure systems. They consist of a number of optical sensor converters, a computer processor and a control indicator. Each optical converter houses an infrared camera.
The fisheye IR detector is the result of a joint development project between Sofradir and Onera, with the support from the French defence procurement agency DGA, which began 24 months ago.