Worlds of David Darling
Encyclopedia of Science
Home > Encyclopedia of Science

active optics

A computer-controlled system that compensates for the distortion of a telescope's mirrors caused by gravity, and thus allows a thinner mirror and a lighter support structure to be used. It works by monitoring the image of a guide star and sending appropriate signals to actuators behind the mirror, which in turn control movable supports to correct the mirror's shape and alignment.

Related category