HIGH APERTURE-RATIO CATADIOPTRIC LENS Russian patent published in 1997 - IPC

FIELD: creation of compact multi-channel high aperture- ratio optical systems. SUBSTANCE: catadioptric lens uses the first compensator that includes three components: a meniscus, with its concave surface facing the space of objects, whose focal power modulus does not exceed 0,03Φ_l, where Φ_l - lens focal power, ring-shaped biconvex lens, and a diverging meniscus at a distance of (0.001 to 0.005) of the catadioptric lens focal length, with its convex surface facing the picture space, a secondary mirror is applied onto the convex surface. The focal power if the three- component compensator is within 0.15 to 0.35 Φ_l; ring-shaped Manjen mirror in the form of a meniscus with a mirror coating on its convex surface facing the space of pictures; secondary mirror with its convex surface facing the picture space; the second aberration compensator in the form of cemented of biconvex and biconcave lenses. The shape of the concave surface of the meniscus of the first compensator is determined by equation: y²+ a₁x + a₂x²+ a₃x³+ a₄x⁴+ a₅x⁵=0, where x, y - coordinates; a₁- a₅ - coefficients. The concave surface of the meniscus of the first compensator is divided into three concentric zones, their middle zone has a dichroic coating providing for principal transmission of radiation of the 1-st spectral region and partial reflection of radiation of the 2-nd spectral region, and the two other zones have a coating reflecting the radiation of the 2-nd spectral region; the apical radii of surfaces of the central zone and peripheral zones have different valves. A convex ring-shaped hyperbolic mirror is installed before the first compensator. EFFECT: improved design. 3 cl, 4 dwg