Free Search (12423 images)
Rating: 0.00/5 (0 votes cast)
- Title IASI optics
- Released 21/06/2006 10:28 am
- Copyright ESA - AOES Medialab
The Infrared Atmospheric Sounding Interferometer (IASI) scanning mirror, which scans up to an angle 48.5° either side of the satellite track, directs incident infrared radiation into the instrument. A series of mirrors focus the beam into the interferometer where the beam is split in two by the beam splitter. The fixed corner cube keeps one beam constant in length whilst the movable corner cube, which moves linearly by two centimetres, generates an optical path difference of four centimetres. A folding mirror then recombines the two beams and the phase difference between the two can be detected. This optical path difference holds the signatures of the range of atmospheric variables of interest.
Each scan takes eight seconds; this includes the time it takes for the beam to be directed into the deep space calibration field of view, as well as to the internal blackbody reference - both are used for calibration purposes.
- Id 232103