OPTICAL SYSTEM OF THERMAL IMAGING DEVICE WITH TWO FIELDS OF VIEW Russian patent published in 2016 - IPC G02B13/14 G02B15/02 

FIELD: optics.

SUBSTANCE: optical system of thermal imaging device consists of fixed along the optical axis of the stationary first component having a first negative, a second positive and a third negative convex-concave lenses, the movable second component comprising a first negative, the second positive and a third positive concave-convex lenses, the fixed third component comprising a first positive concave-convex lens, second negative convex-concave lens and a third positive biconvex lens, and a photodetector with a cooled diaphragm. Movable second component is installed with possibility of input/output to the optical path.

EFFECT: longer of focal distance while maintaining of value of tele-shortening coefficient and image quality.

1 cl, 1 dwg, 3 tbl