Telescopes are made in such a way that its reflecting system continues to be improved. The mirrors are used in combination with the lens, which use both reflective and refractive properties of a system to form images called catadioptric.
Catadioptric telescopes are special types of telescopes that combine the process of a refraction and reflection system in focusing images or objects. It has specifically shaped lenses and mirrors in spherical surfaces that are easily manufactured. They have a higher degree of error correction compared to other lens and mirror counterparts. It is also designed with a wide field of view.
Catadioptric telescopes have two categories namely true catadioptric and hybrid catadioptric. The first one functions with both reflective and refractive properties working while the latter that uses a mirror telescope can work without the refractive element. Instead, it uses a refractive field-corrector.
Aside from these types, catadioptric telescopes are grouped according to the lens corrector. There are those that use sub-aperture correctors which are followed by one or more optical surfaces. It is typically placed after the mirror element. On the other hand, full-aperture lens correctors combine a number of spherical primary mirrors to ease the fabrication of the mirror. The performance level of every catadioptric telescope depends on its properties and manufacturer.
Type of Catadioptric Telescope