What is Adaptive optics?
{{jargon|date=January 2024}} {{No footnotes|date=September 2020}} [[File:Adaptive_optics_correct.png|thumb|A deformable mirror can be used to correct wavefront errors in an astronomical telescope.]] '''Adaptive optics''' is a [[technology]] to improve the performance of [[optics|optical systems]] by reducing the effects of rapidly changing optical [[distortion]]. It is commonly used on [[Astronomy|astronomical]] [[telescope]]s to remove the effects of [[Atmosphere of Earth|atmospheric]] distortion. Adaptive optical works by measuring the distortion and rapidly compensating for it either using deformable [[mirror]]s or material with variable [[Refraction|refractive]] properties. While the idea was theoretically understood for some time, it was only advances in [[computer]] technology during the 1990s that finally made the technique practical. Adaptive optics should not be confused with [[active optics]], which works on a longer timescale to correct the primary mirror [[geometry]] itself. The simplest form of adaptive optics is '''tip-tilt''' correction, which corresponds to correction of the [[Tilt (optics)|tilts]] of the wavefront in two dimensions (equal to correction of the position offsets for the image). This is performed using a rapidly moving tip-tilt mirror which makes small [[rotation]]s around two of its [[Axis of rotation|axes]]. A significant fraction of the distortion introduced by the atmosphere can be removed in this way. Tip-tilt mirrors are widely used in night time and solar [[telescope]]s, to correct the effect introduced by [[Earth]]'s [[atmosphere]] on the light path and improve image quality. [[Tip-tilt mirrors]] are effectively [[Segmentation|segmented]] adaptive optics mirrors with only one segment which can tip and tilt, rather than having an array of multiple segments which can tip and tilt independently. == Other websites == * [http://www.eso.org/projects/aot/introduction.html Description of Active & Adaptive Optics] E.S.O. * [http://www.ctio.noao.edu/~atokovin/tutorial/intro.html A