INFRARED SYSTEM WITH TWO FIELDS OF VIEW Russian patent published in 2019 - IPC G02B13/14 G02B15/14 

FIELD: optics; instrument engineering.

SUBSTANCE: invention relates to optical instrument-making and relates to an infrared system with two fields of view. System consists of three optical components and a photodetector device arranged along the optical axis. First component comprises a first positive convex-concave and a second negative aspherical lens. Second component comprises a biconcave aspherical lens and is movable along an optical axis. Third component comprises a first biconvex and a second negative aspherical lens. For focal distances f'_I, f'_II and f'_III first, second and third components, respectively, and maximum focal distance of system f'_max following relationships are satisfied: 0.5 < f'_I/f'_max < 0.7; -0.15 < f'_II/f'_max <-0.07; 0.1 < f'_III/f'_max < 0.2.

EFFECT: technical result consists in reducing the value of movement of the second component and the value of the short-circuiting ratio.

1 cl, 1 dwg, 4 tbl