Patent ID: 7283251

Claim:
A method of performing closed loop correction of phase aberrations, comprising the steps of: directing an incoming light beam into a black fringe wavefront sensor via an adaptive optical device; dividing the incoming light beam into a measurement beam and a reference beam using at least one of a plurality of optical elements; altering the path length of the measurement beam and the location of black fringe by modulating a ramp voltage of a modulator affixed to at least one of the plurality of optical elements; combining the measurement beam and the reference beam into a common output beam using at least one of the plurality of optical elements; detecting black fringe in the common output beam using a plurality of detectors mapped to the adaptive optical device; storing, as tagged ramp voltages, a corresponding ramp voltage for each of the plurality of detectors upon detecting black fringe by each of the plurality of detectors; calculating phase errors based upon the tagged ramp voltages and modulator scaling; calculating a plurality of adaptive optics correction voltages based upon the phase errors; transmitting the adaptive optics correction voltages to the adaptive optical device; and applying the adaptive optics correction voltages to the adaptive optical device to correct phase aberrations of the incoming light beam via phase conjugation.