Infrared camera sensor works at room temperature

Traditional infrared cameras for wavelengths above five micrometers like it cold – the sensor used inside them has to be constantly cooled down to about -193°C.

Uncooled imagers for the long-wave infrared range do already exist today, but they are mainly used in the military sphere and are more or less unavailable on the European market.

This is now set to change thanks to research scientists at the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg, who have succeeded in producing an imaging sensor for the long-wave infrared range that functions at room temperature.

’We could be the first in Germany to offer this technology,’ said Dr Dirk Weiler, a scientist at the IMS.

At the heart of the IRFPA (Infrared Focal Plane Array) sensor is a microbolometer – a temperature-sensitive detector that absorbs long-wave infrared light. To produce a two-dimensional image, several microbolometers are combined to form an array. If the microbolometer absorbs light from a heat source, its interior temperature rises and its electrical resistance changes. A readout chip then converts this resistance value directly into a digital signal.