Precision with glass ceramics

The new joint European satellite, MSG-1, will replace the Meteosat series in 2004. The MSG-1 will have a central optical element made from SCHOTT’s “ZERODUR®” glass ceramic.
Satellites would be less effective if they were unable to direct the already weak radiation they collect completely and with great precision to the respective detectors. This requires sophisticated optics. Mirrors that must keep their shape even under extreme temperatures are the heart of this optical system. “ZERODUR®”, a glass ceramic produced by SCHOTT, serves as the substrate material for the reflecting metal coating. It has zero thermal expansion, and the material can be polished to an extremely smooth surface. “ZERODUR®” has been tried and tested in geostationary satellites for more than 25 years and was already used in the first Meteosat weather satellite at the end of the 1970s.