Patent ID: 7346085

Claim:
A system for combining a plurality of light beams into a single coherent output beam in multiple stages, comprising: a master oscillator transmitting a light beam; a beam splitter splitting the light beam into N light beams; a first phase modulation stage comprising N phase modulators modulating the N light beams; a group of N beam splitters further splitting each of the N light beams into N groups of M light beams for a total of M×N light beams; a second phase modulation stage comprising N groups of M modulators modulating the M×N light beams; a first diffractive optical element combining M×N light beams from the second phase modulation stage into N coherent beams of M beams each; a means for sampling the N coherent beams; a second feedback loop deriving M×N phase correction signals from the sampling of N coherent beams for locking phases of M light beams in each of N groups at the second phase modulation stage; a second diffractive optical element combining the N coherent beams into a single coherent output beam; a means for sampling the single coherent output beam; and a first feedback loop deriving N phase correction signals from the sampling of the single coherent output beam for locking phases of the N light beams at the first phase modulation stage; wherein M and N are integers greater than 1.