Optical instrument e.g. telescope, for e.g. low orbit satellite, has cavity comprising inner rigid envelope constituted of material presenting high thermal inertia to dampen instantaneous variations of incident radiant flux

摘要

The instrument (1) has a cavity (2) comprising an inner rigid envelope (20) around a primary mirror (3) comprising an active surface subjected to instantaneous variations of an incident radiant flux. The envelope is constituted of a material e.g. aluminum or beryllium, having high thermal inertia to dampen the instantaneous variations. The envelope extends on a cavity part that is near the mirror, where the part moves from the mirror to a distance lesser than the total length of the cavity.