Accession Number : ADD014839

Title :   Efficient Dynamic Phasefront Modulation System for Free-Space Optical Communications.

Descriptive Note : Patent, Filed 9 Sep 88, patented 22 Jan 91,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Gilbreath, G C ; Davidson, Frederic M

Report Date : 22 Jan 1991

Pagination or Media Count : 15

Abstract : An optical communications system is disclosed for correcting in real-time the wavefront distortions of a beam from a coherent optical transmitting source. The system includes a collimating lens and beam splitter for receiving a distorted wavefront signal beam and splitting the beam into a pump beam and a weaker intensity signal beam. The system includes a detector and computer for measuring the beam distortion and specifying a compensatory wavefront. The weaker intensity signal beam is modified in a 2-D spatial light modulator according to a compensatory wavefront. A photo-refractive material is used to couple energy from the pump beam to the compensated wavefront signal beam thereby producing a corrected and intensity-enhanced communications beam.

Descriptors :   BEAM SPLITTING, COHERENT OPTICAL RADIATION, COLLIMATORS, COMMUNICATION AND RADIO SYSTEMS, COMPENSATION, CORRECTIONS, DISTORTION, LENSES, MODULATION, OPTICAL COMMUNICATIONS, OPTICAL EQUIPMENT, PUMPS, SIGNALS, TRANSMITTING, WAVEFRONTS

Subject Categories : Optics
      Command, Control and Communications Systems

Distribution Statement : APPROVED FOR PUBLIC RELEASE