An Etymological Dictionary of Astronomy and Astrophysics

A telescope with a spherical concave primary mirror in which the aberration produced by the spherical mirror is compensated for by a thin correcting lens placed at the opening of the telescope tube. Its very wide-field performance makes it suitable for surveys.

See also: Named after Bernhard Woldemar Schmidt (1879-1935), a German optician of
Estonian origin, who invented the telescope in 1930; → telescope.