Solar-illuminated diffuse reflectance panels are used for in-flight calibration of imaging systems used in earth-observing satellite instruments. Labsphere's Space-Grade (SG) Spectralon® diffuse reflectance material was developed specifically for this application, and has become the material of choice in the remote sensing community.
Typically, a Spectralon diffuser panel is deployed into the instrument's field of view at specific points in the orbit of the satellite platform. The panel is illuminated by the sun at precisely known angles and irradiance levels. The spectral reflectance factor of the Spectralon panels is calibrated on-ground, so that the reflected radiance presented to the instrument is known. The response of the instrument to this known spectral radiance can therefore be used to verify the instrument's calibration, and to recalibrate as-needed.
Labsphere's Space-Grade Spectralon is a highly-reflective, near-lambertian reflectance material. It is manufactured and handled according to a stringent process designed to minimize trace molecular contamination, and thus, to reduce or eliminate degradation of the diffuser upon exposure to the space environment such as solar UV and atomic oxygen. Space-Grade Spectralon has been tested and proven both on-ground and in space and is currently being used on NASA's MISR satellite.
