Editing Schmidt camera (section)

====Function====
[[File:Aberration de sphéricité d'un miroir sphérique concave.svg|thumb|left]]
[[File:Correction par lame asphérique de Schmidt.svg|thumb|left|Example of an optical system using just a spherical mirror (''top'') and a spherical mirror combined with a Schmidt corrector plate (''bottom'').]]
Schmidt corrector plates work because they are aspheric lenses with spherical aberration that is equal to but opposite of the spherical primary mirrors they are placed in front of. They are placed at the center of curvature "'''C'''" of the mirrors for a pure Schmidt camera and just behind the prime focus for a [[Schmidt–Cassegrain telescope|Schmidt–Cassegrain]]. The Schmidt corrector is thicker in the middle and the edge. This corrects the light paths so light reflected from the outer part of the mirror and light reflected from the inner portion of the mirror is brought to the same common focus "'''F'''". The Schmidt corrector only corrects for spherical aberration. It does not change the focal length of the system.