The Schmidt camera telescope, invented in 1930 by Bernard Schmidt, is a catadioptric system used for wide-angle photography of star fields. The primary mirror is spherical instead of paraboloidal, which requires that a special correcting lens be used on the front of the tube. The Maksutov telescope, invented by D. D. Maksutov in 1941, is similar in design and purpose to the Schmidt telescope but has a spherical meniscus in place of the correcting plate of the Schmidt.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.