Patent ID: 6384944
Filing Date: 2002-05-07
Classification: H04B

Abstract:
An integral transmitter-receiver optical communication apparatus, comprising:a transmitter-receiver device comprising: a transmitter having a laser source for emitting a laser beam modulated in accordance with a transmission information signal; a receiver having a position detecting sensor and a light receiving element which receive a complementing modulated laser beam transmitted from a complementing transmitter; and a beam splitting device for splitting said modulated laser beam and said complementing modulated laser beam which are incident thereon as two separate laser beams; a telescopic optical system for transmitting said modulated laser beam emitted by said laser source and for receiving said complementing modulated laser beam transmitted from said complementing transmitter; and a light beam deflecting device positioned between said telescopic optical system and said transmitter-receiver device, wherein said light beam deflecting device is controlled in accordance with a signal output from said position detecting sensor; wherein said beam splitting device comprises: in order from the light beam deflecting device side, a polarization beam splitting plane which allows a first linearly polarized laser beam of said modulated laser beam emitted from said laser source to pass therethrough to proceed towards said light beam deflecting device, and reflects a second linearly polarized laser beam of said complementing modulated laser beam transmitted from said complementing transmitter, said second linearly polarized laser beam having a phase different from a phase of said first linearly polarized laser beam by 90 degrees; and a beam splitting plane for splitting said second linearly polarized laser beam reflected by said polarization beam splitting plane into two separate laser beams to be respectively received by said position detecting sensor and said light receiving element; wherein said modulated laser beam emitted from said laser source has a non-circular shape of intensity distribution, a first length in a &thgr;-parallel direction of a cross section taken along a plane perpendicular to said modulated laser beam being shorter than a second length in a &thgr;-perpendicular direction of said cross section, said first length and said second length extending perpendicularly to each other; and wherein the orientation of said laser source is determined so that said &thgr;-parallel direction becomes substantially parallel to an optical axis extending from said polarization beam splitting plane to said beam splitting plane.