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12 November 2008


Sofradir to supply Astrium with three-band SWIR detector for environmental mapping

Satellites and space equipment supplier Astrium SAS has awarded a €6.7m (about $10m) contract to Sofradir of Veurey-Voroize, France, which manufactures infrared (IR) detectors for military, space and industrial applications, to develop and manufacture a custom-made three-band (1.3-2.3 micron wavelength) short-wave infrared (SWIR) detector for the Multi-Spectral Instrument (MSI), an earth observation instrument onboard the Sentinel-2 satellite.

Sentinel-2 will provide a powerful and fully operational information capability in the frame of the Global Monitoring for Environment and Security (GMES) initiative (a joint undertaking of the European Commission and the European Space Agency). The mission is designed as an optical high-resolution multi-spectral mission to provide sustained operational land services for a period of at least 15 years, involving a series of several satellites.

The Sentinel-2 Multi-Spectral Instrument (MSI) is a filter-based push-broom imager that provides imagery in 13 spectral channels with spatial resolutions ranging from 10 to 60m and fast revisit allowed by a 290km swath width (the strip of Earth scanned by the satellite). The instrument is required to operate over a wide spectral range extending from the visible near-infrared (VNIR, 400-1100nm) to the short-wave infrared (SWIR, 1100-2500nm) spectral range.

For delivery to Astrium SAS in 2010, Sofradir’s detector will be used to offer more discrimination of trees, crops, and other environmental elements, including the density of humid air, and is designed and screened to function for the in-orbit lifetime for each of the two Sentinel-2 satellites (just over 7 years each).

The three-band SWIR detector uses Sofradir's mercury cadmium telluride (MCT/HgCdTe) focal plane array technology, which is space qualified and offers the highest performance for IR object-identification, it is claimed. The detector includes three linear arrays of 1298 pixels at 15 micron pitch. Each array is sensitive to one waveband, centered on 1.4, 1.6 and 2.2 microns, respectively. Since the arrays are hybridized on the same readout circuit, this results in very accurate relative positioning (i.e. all three arrays scan the same object using the same pixel).

“The reliability of Sofradir’s technology for 15 micron pixel pitch detectors and our experience in space project management were the crucial factors in Astrium’s decision to choose Sofradir from among other European suppliers,” says Sofradir’s CEO Philippe Bensussan. “This contract allows us to strengthen our engagement in a high-priority issue, global environment monitoring,” he adds.

Sofradir is involved in a growing number of satellite and space missions, covering applications such as earth mapping, environment and disaster monitoring, and planet exploration. The firm’s MCT IR detectors are in orbit in the Helios II and Venus Express satellites, and will soon be deployed in the SPIRALE satellite. Its detectors for the Second Generation GLI/Global Change Observation Mission (SGLI/G-COM) are now ready for flight model production.

See related items:

Sofradir to acquire IR equipment maker Electrophysics

Sofradir launches compact cooled 1/2 TV format MWIR detector

Sofradir promotes deputy director of uncooled IR detector subsidiary ULIS to MD

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