Coherent (phased array) and wavelength (spectral) beam combining compared

摘要

Significant progress has been recently reported on beam combining of arrays of fiber and semiconductor lasers usingboth coherent (phased array) and wavelength (spectral) techniques. The choice between these two classes of beamcombiningtechniques has implications for the degree of control required on the array elements and on the opticalsystem that is using the beam-combined array. Coherent beam combining imposes more stringent requirements onarray-element control (spectrum, phase, amplitude, and polarization) than wavelength combining. Also, wavelengthcombinedsystems should degrade more gracefully than coherent systems and require fewer changes to optical systemsas the number of elements is varied.