System and Method for Gradient Interferometrically Locked Laser Source

A method for generating measurement signals related to a plurality of phase differences between neighboring output beams of an optical beam generator, comprising:

• projecting a plurality of output beams, each output beam emanating from an associated output beam source;
• tailoring a collimation state of the plurality of output beams by a plurality of lenses in a lens array;
• forming a plurality of sampling regions on an output window;
• directing, by the sampling regions, the plurality of output beams to a detector producing an optical sample signal associated with the plurality of output beams.

A gradient interferometrically locked laser source, comprising:

• a laser source configured to produce an optical beam;
• a beam splitter configured to split the optical beam into a plurality of output beams;
• a plurality of channel control devices configured to control a phase of the plurality of output beams and apply a modulation pattern to enable measurement of phase differences between the plurality of output beams;
• a beam combiner configured with a plurality of lenses to spatially combine the plurality of output beams in an array to form a projected laser beam;
• an output window having a plurality of sampling regions configured to direct samples of neighboring beam pairs back through the plurality of lenses to form a plurality of focused pairs of beams;
• a plurality of detectors configured to produce a plurality of optical sample signals associated with the plurality of focused pairs of beams;
• a demodulator configured to demodulate the plurality of output beams and further configured to determine phase difference measurements associated with the plurality of output beams;
• a phase unwrapper configured to receive the phase difference measurements and determine, based at least in part on the phase difference measurements, a phase estimate;
• and
• an actuator filter and control block configured to receive the phase estimate and one or more of a beam steering offset, a beam pattern phase offset, and a calibration error offset and further configured to produce phase command signals to adjust one or more parameters of the plurality of output beams.