CATADIOPTRIC LENS Russian patent published in 2015 - IPC G02B17/08 

FIELD: physics.

SUBSTANCE: lens comprises a first mirror in the form of an off-axis fragment of a concave spherical mirror whose concave surface faces the object plane, a lens aberration corrector in the form of three separate axially symmetric lenses made of different optical materials: biconvex, biconcave and positive meniscus, a second mirror in the form of an off-axis fragment of a convex mirror whose convex surface faces the lens aberration corrector, a third mirror in the form of an off-axis fragment of a concave spherical mirror whose concave surface faces the object plane, and an aperture diaphragm which coincides with the holder of the first surface of the second lens aberration corrector. The centres of curvature of all optical surfaces are located on one common axis. In the meridian section of the lens, the first mirror is located lower than the optical axis and the second and third mirrors are located higher than the optical axis. The optical power, refraction indices and dispersion coefficients satisfy relationships given in the claim.

EFFECT: high image quality of the catadioptric lens without centre shielding in a wide spectral range and high manufacturability of said lens.

2 cl, 3 dwg, 1 tbl