Aplanatic Meniscus Lens Corrector for Ritchey-Chrétien Telescopes.

An analytically designed aplanatic meniscus lens is proposed for increasing the field of view (FoV) of Ritchey-Chrétien (RC) telescopes. Compared to other field correctors, the proposed solution does not affect the initial RC telescope's aplanatic properties, and it can be added or removed from an existing RC telescope without changing the mirrors' shape. The final system features less astigmatism, which is balanced to flatten the image surface.