Infrared and visible spectrum detectors and CCD sensors have negative temperature performance coefficients. When cooled they become more sensitive and their noise generation characteristics reduce. Marlow provides thermoelectric coolers (TECs) that use single-stage cooling for near-room temperature operation through six-stages to cool to about 170 Kelvin (-103°C).
Materials that benefit from cooling, used by FLIR or other radiometric sensing systems, are Mercury Cadmium Telluride (MCT), lead sulfide (PbS), lead selenide (PbSe), silicon, indium-doped gallium arsenide (GaInAs), indium arsenide (InAs), gallium indium arsenide phosphide (GaInAsP), gallium arsenide (GaAs), gallium aluminum arsenide (GaAlAs) and other quaternaries (four-element combinations).
Thermoelectric coolers are lightweight, small and rugged. They have no moving parts, cause no vibration and after cleaning can be used in vacuum enclosures. They function in any orientation and need no connecting lines (except for two power leads). They can support ball, stitch or ultrasonic bonding to be performed on the detector arrays attached to the top stage cold ceramic of the TEC.
