HIGH-APERTURE CATADIOPTRIC LENS Russian patent published in 2009 - IPC G02B17/08 

FIELD: physics.

SUBSTANCE: high-aperture catadioptric lens has a front component, a main mirror in form of a Mangin lens with a central opening, a secondary mirror and a near-focal compensator. The front component is made from a converging lens and a diverging lens with a central opening, separated by a thin air lens, whose concave side faces the object, with thickness on the axis of not more than 0.4% of the focal distance f' of the lens, and limits of radius of curvature of surfaces of 0.3-0.5 of f'. The secondary mirror is deposited on the second surface of the first lens of the front component. The near-focal component is made from converging and diverging lenses, which are mounted in a convergent bundle. All optical refracting elements are made from the same type of glass.

EFFECT: improved image quality in a wide spectral range with increase of aperture ratio at the same time.

1 dwg, 1 app