WIDE-ANGLE RETROFOCUS OBJECTIVE Russian patent published in 2021 - IPC G02B9/64 G02B11/34 

FIELD: photography.

SUBSTANCE: objective can be used in reflex photographic equipment. The objective comprises two components. The first component is positive and comprises consecutively arranged positive meniscus lens facing the space of the object with the convex surface, a first, second and third negative meniscus lenses facing the space of the object with the convex surface, a single biconvex lens, a fourth negative meniscus lens facing the space of the object with the convex surface, and a positive double-adhered meniscus lens facing the space of the object with the convex surface and consisting of a biconvex and a biconcave lenses. The second component is positive and comprises a first positive adhered doublet consisting of a negative meniscus lens facing the space of the object with the convex surface and a biconvex lens, and a second negative adhered doublet consisting of a negative meniscus lens facing the space of the object with the convex surface and a biconvex lens.

EFFECT: improved image quality over the field and increased manufacturability due to the reduction in the amount of used grades of glass with the maintained relative aperture and the value of the angular field of view.

2 cl, 2 dwg, 1 tbl