Infrared Binoculars Operate At Ambient Temperatures

Bolide is the name of new infrared binoculars that use a detector devised at the infrared laboratory of the Laboratory for Electronics, Technology and Instrument (LETI) located in southeastern France. The LETI researchers have replaced detectors that have to be cooled to about -258°F with microbolometers that work at ambient temperatures. The microbolometers work in two stages, using two superimposed materials: an absorber that converts the incident infrared radiation into an increase in temperature; and a temperature sensor that converts this increase into electrical signals. The signals are then read using an IC that processes them to obtain a useable electrical signal. Each detector consists of a matrix of some 76,800 microbolometers measuring less than 50 micrometers in size. Each microbolometer is linked with a picture element in the final image. Although the performance of Bolide night binoculars is not as good as that of existing equipment in terms of range, they are both lighter and less expensive. The ambient temperature-operating devices are expected to find use in the military and space fields, as well as in the civil sector for preventive maintenance or monitoring industrial processes. In the long term, they are expected to find use in enhancing the vision of car drivers. An initial prototype is planned for this fall.