Study of an uncooled focal plane array for thermal observation of the Earth

A medium scale infrared sensor dedicated to applications in agriculture, hydrology, forest fires and environment has been studied within the framework of a European Commission contract. An innovative push broom concept using linear arrays of uncooled microbolometers has been preferred to a traditional scanner concept using cryogenically cooled photoconductor detectors, for its performances and because it does not require any cooling, and is free of micro-vibrations. The instrument offers a resolution of 250 m for a swath width of about 1400 km, and the radiometric resolution is better than 0.5 K in two spectral channels around 11 and 12 mu m. Focal plane topology and radiometric modelling will be presented in this paper, demonstrating the suitability of microbolometers focal planes for medium resolution radiometric missions on board Low Earth Orbit satellites.