FOUR-MIRROR-LENS OPTICAL SYSTEM Russian patent published in 2017 - IPC G02B17/08 G02B23/04 

FIELD: physics.

SUBSTANCE: optical system comprises a main concave aspherical mirror, before which a negative meniscus is set, the lens compensator of the far-infrared range is mounted after the main mirror, the first surface of which is a spectrum splitter and misses the far-infrared range and reflects the visible, short-IR and mid-IR ranges, the doublet mirror lens general for the visible, short-IR and mid-IR ranges, the front focal plane of which is offset against the rear focal plane of the mirror lens to form the beams with a small angular divergence. The second spectrum splitter is located after the general lens, after passing through which the lens is attached to the mid-IR range. A doublet compensator and the third spectrum splitter are mounted general for the visible and short-IR ranges after they are reflected from the second spectrum splitter, after the passage through which the lens is attached for the short-IR range, and a lens is attached to the visible range after it is reflected from the third spectrum splitter.

EFFECT: obtaining images at four receivers simultaneously, increasing the angular field in the object space, increasing the relative holes in each of the channels and reducing the number of aspheric surfaces.

1 dwg, 1 tbl