schmidt telescope

noun

1. a wide-angle reflecting telescope used primarily for astronomical photography, in which spherical aberration and coma are reduced to a minimum by means of a spherical mirror with a corrector plate near its focus.

noun

1. a catadioptric telescope designed to produce a very sharp image of a large area of sky in one photographic exposure. It incorporates a thin specially shaped glass plate at the centre of curvature of a short-focus spherical primary mirror so that the resulting image, which is focused on a photographic plate, is free from spherical aberration, coma, and astigmatism