HIGH-APERTURE LENS Russian patent published in 2017 - IPC G02B9/34 G02B13/14 

FIELD: optics.

SUBSTANCE: invention can be used in imaging devices. High-aperture objective consists of four lenses lying on beam path: first and second lenses are single positive meniscus, concave sides of which face image. Third lens is single negative meniscus, concave side of which faces image. Fourth lens is single positive meniscus, concave side of which faces image. First and fourth lenses are made of germanium, and second and third ones are made of zinc selenide. Radius of second optical surface on beam path in magnitude is equal to radius of sixth optical surface on beam path.

EFFECT: technical result is high image quality at reduced dimensions.

1 cl, 1 dwg, 2 tbl