INFRARED TELEPHOTO LENS WITH TWO VISION FIELDS Russian patent published in 2017 - IPC G02B13/02 G02B13/14 G02B15/14 

FIELD: physics.

SUBSTANCE: telephoto lens contains four components on the beam path. The first component is immobile, containing a positive meniscus, which convex side faces the plane of objects, and additionally introduced single negative meniscus, which convex side faces the plane of objects. The second surface of the first meniscus and the first surface of the second meniscus are aspherical. The second component is a mobile biconcave lens, which second surface is aspherical. The third component is an immobile positive component containing a positive meniscus, which convex side faces the plane of objects, and which second surface is aspherical, and an additionally introduced negative meniscus, which convex side faces the plane of objects, and which surface is made aspherical. The fourth component is an immobile single positive convex-concave lens, which convex side faces the plane of objects, and which second surface is aspherical-diffractive.

EFFECT: creation of a compact infrared telephoto lens with two vision fields and a low tele-distortion ratio with high image quality.

8 dwg, 1 tbl