EXTRA WIDE-ANGLE LENS Russian patent published in 2022 - IPC G02B9/64 G02B9/04 

FIELD: physics.

SUBSTANCE: invention can be used as a photographic lens. Extra-wide-angle lens comprises two components, between which there is an aperture diaphragm. First component consists of a negative meniscus whose convex side faces the plane of objects, the second surface of which is an aspherical, flat-concave lens, a concave-flat lens, a biconvex lens and a positive meniscus whose convex side faces the plane of the objects, the second component consists of two glued lenses, wherein the first of them is glued from a biconcave lens and a biconvex lens, the second is glued from a biconvex lens and a negative meniscus, and a positive meniscus whose convex side faces the plane of the objects. Following ratios are satisfied: where f', f'₁ is the focal distance of the lens and its first component, respectively; L is the length along the optical axis between the first and last refracting surfaces of the lens; L₂ is the length along the optical axis between the first and last refracting surfaces of the second component of the lens.

EFFECT: expansion of field of view in space of objects up to 190°, high image quality.

1 cl, 2 dwg, 1 tbl