Patent ID: 7079774

Claim:
A free-space optical communication system comprising: a plurality of remote transmit/receive subscriber terminals each comprising a source of modulated optical radiation and a photo-detector; and a base terminal, comprising: (a) a plurality of sources of modulated optical radiation and a corresponding plurality of associated beam shaping devices; and (b) a receiving system comprising a plurality of photo-detectors and a single lens wide-angle objective shared for coupling optical radiation from respective remote terminals to respective photo-detectors of the receiving system of the base terminal; wherein: the single lens wide-angle objective comprises a set of concentric spherical layers made of optical materials with different indices of refraction, such that a spherical focal surface of the lens has a radius of curvature R f >R 0 where R f is the radius of curvature of the lens focal surface; and R 0 is the radius of curvature of the lens external surface, and the single lens wide-angle objective is coupled only to the respective photo-detectors of the receiving system of the base terminal, and each optical beam shaping device has no common optical element with the objective lens and with others of the beam shaping devices at the base terminal.