CATADIOPTRIC LENS Russian patent published in 2014 - IPC G02B17/08 

FIELD: physics.

SUBSTANCE: catadioptric lens consists of, on the beam path, a plane-convex lens whose convex surface faces the object plane, the centre of the plane surface of which is coated with a mirror coating, a Mangin mirror whose concave surface faces the object plane, at the centre of which there is an opening, and a positive glued meniscus whose convex surface faces the object plane. The plane-convex lens and the Mangin mirror are made of the same material, the average dispersion of which is in the range 63≥υD≥66. The distance from the first lens to the glued meniscus is in the range from 0.35×f' to 0.45×f', where: υD is the average dispersion (Abbe number) for the D spectral line, and f' is the focal distance of the lens.

EFFECT: improved image quality by reducing coordinate chromatism, correction of image skewness and smaller dimensions of the device using said lens.

4 dwg, 1 tbl