adaptive optics

from The Collaborative International Dictionary of English v.0.48

adaptive optics \adaptive optics\ n. (Astron.)
   an optical system used in some telescopes since the 1980's
   which rapidly changes the shape of the primary reflecting
   mirror to adjust for distortions of light which are caused by
   atmospheric turbulence. By reducing the distortions caused by
   the atmosphere, telescopes fitted with such optics can
   achieve a higher resolving power than normal telescopes with
   static mirrors.
   [PJC]