Which combination of optics is used in the Schmidt-Cassegrain telescope for producing high-quality wide-angle images of the sky?
A) a single, short-focal-length spherical mirror
B) a parabolic mirror of short focal length, used at prime focus
C) two lenses of different glass, one convex, the other concave, to reduce chromatic aberration
D) a spherical primary mirror with a thin correcting lens ahead of it

Question

Quizplus · Accepted Answer

The Schmidt-Cassegrain telescope uses a spherical primary mirror with a thin correcting lens ahead of it to reduce spherical aberration and create a wide-angle view. This correcting lens is referred to as a corrector plate and is made of optical glass. Using this combination of optics helps to produce high-quality wide-angle images of the sky.

Which Combination of Optics Is Used in the Schmidt-Cassegrain Telescope