Coherent Summation of Laser Beams Using Binary Phase Gratings

摘要

A method for coherent addition of lasers is presented that uses binary phase only gratings. It is shown that a grating that splits a single beam into N equal orders with high efficiency can be used in reverse to convert N laser beams into a single beam with the same efficiency. Experiments to demonstrate the conversion of seven beams to one beam are performed with a resulting conversion efficiency of 75%. An experimental apparatus is described that adds the power from both two and three Helium Neon lasers (wavelength, 3.39 micrometers) with efficiencies as high as 83%. Keywords: Binary phase gratings; Combining laser beams coherently; Coupling efficiency; Reprints.