Method and system for increasing the size of the area scanned by an airborne electro-optic reconnaissance system in a given time

Abstract

The invention relates to an airborne reconnaissance system which comprises: (a) optical unit for acquiring light rays from a terrain portion, said optical unit comprises a plurality of optical components that are positioned along an optical path and designed to maneuver said light rays to produce at a focal plane an acquired image of a terrain portion, said acquired image having an area S which is several times larger than the area A of a focal plane array which is positioned at same focal plane; (b) gimbals unit for performing a continuous back and forth across-track scanning movement of a respective line of sight formed between said optical unit and the terrain below the aircraft; (c) a first back-scanning mirror along said optical path, for compensating for said continuous across track movement of the line of sight, said compensation is performed during a respective integration period for a section of said acquired image of area S which falls during said period on said focal plane array; and (d) a second, along-track mirror also positioned along said optical path, which alternates between plurality of along track states, each state causes a different diversion of the light rays within said optical path thereby to impinge on said focal plane array another along-track section of said acquired image of area S; and (e) capturing means for recording in each state of said along-track mirror the corresponding section of the terrain image which is impinged during said state on the focal plane array.