INFRARED TELEPHOTO LENS WITH TWO FIELDS OF VIEW Russian patent published in 2024 - IPC G02B13/14 

FIELD: optics.

SUBSTANCE: invention relates to telephoto lenses for thermal imaging devices based on cooled matrix receivers. Infrared telephoto lens with two fields of view consists of four components arranged along an optical axis. First component is fixed, consists of three lenses, the first convex-concave positive lens from germanium, facing the convex surface to the plane of objects, the second negative plano-concave lens from fluorite, facing the concave surface to the plane of the objects, third positive convex-concave zinc selenide lens whose convex surface faces the plane of objects. Second and third components are movable and have two fixed positions. Second component is made in the form of a negative convex-concave lens made of germanium with its convex surface facing the plane of objects. Third component is made in the form of a positive plano-convex lens made of germanium with its convex surface facing the image plane; the second surface of the lens is aspherical. Fourth fixed component consists of a positive convex-concave lens made of germanium with its convex surface facing the plane of objects; the first surface of the lens is aspherical.

EFFECT: reducing the number of aspherical surfaces while maintaining the number of optical elements, increasing the magnitude of changing the field of view while maintaining image quality.

1 cl, 10 dwg, 6 tbl