A Maksutov telescope is a type of catadioptric telescope (an instrument combining mirrors and lenses), developed by the Russian optical specialist Dmitri Maksutov (1896–1964). It uses a spheroidal primary mirror, a deeply-curved spheroidal meniscus corrector plate, and a small spheroidal secondary mirror fixed to, or simply silvered on to, the back of the corrector plate, to give a triple-folded optical path. The result is a very compact telescope of long focal length that gives a wide field of view and images of excellent quality. Well-made 'Maks' outperform Schmidt-Cassegrain telescopes of equal quality and have became popular with amateur astronomers, especially for astrophotography and planetary viewing. However, because their corrector plates are difficult to manufacture for large aperture instruments, their professional application is limited.