Simplified system and method for compensated laser beam propagation

A compensated laser beam projection method comprising the steps of:

• a) projecting a laser beam to an aperture sharing element means that functions to produce a majority projected laser beam sample and a minority projected laser beam sample;
• b) directing the majority projected laser beam sample through a first optical system means that functions to direct the majority projected laser beam sample to a primary phase correction device means that functions to pre-compensate the phase of the majority projected laser beam sample to enable focusing the beam through a medium to a target to form a pre-compensated majority projected laser beam sample;
• c) wherein said first optical system means further functions to direct the pre-compensated majority projected laser beam sample through said medium to said target;
• d) directing the minority projected laser beam sample through the aperture sharing element means to a retro-reflector array means that functions to provide a sampled conjugation of a wavefront phase of the minority projected laser beam sample to produce a pseudo-conjugated minority projected laser beam sample;
• e) directing the pseudo-conjugated minority projected laser beam sample to reflect from the front surface of said aperture sharing element means and then transmitting through a second optical system means that functions to direct the pseudo-conjugated minority projected laser beam sample to a secondary phase correction device means that functions to null a wavefront phase of the pseudo-conjugated minority projected laser beam and to produce a compensated projected laser beam sample;
• f) directing the compensated projected laser beam sample to a beam splitter means that functions to direct the compensated projected laser beam sample to a projected laser wavefront sensor means functioning to measure a wavefront phase of the compensated projected laser beam sample;
• g) wherein the projected laser wavefront sensor means further functions to produce a projected laser error signal;
• h) forming a beacon beam that transmits from the target, through the medium, through said first optical system means that further functions to direct the beacon beam to the primary phase correction device means that further functions to produce a partially compensated beacon beam;
• i) passing the partially compensated beacon beam through said aperture sharing element means functioning to produce a partially compensated beacon beam sample;
• and
• j) directing the partially compensated beacon beam sample through said second optical system means that further functions to direct the partially compensated beacon beam sample to the secondary phase correction device means that functions to null a wavefront phase of said partially compensated beacon beam sample to produce a compensated beacon beam sample;
• k) directing the compensated beacon beam sample to a beam splitter means that functions to direct the compensated beacon beam sample to a beacon wavefront sensor means functioning to measure a wavefront phase of the compensated beacon beam sample;
• l) wherein the beacon wavefront sensor means further functions to produce a beacon error signal;
• m) processing said beacon error signal to control a wavefront phase of the primary phase correction device means to null the wavefront phase of the compensated beacon beam sample observed on said beacon wavefront sensor means;
• and
• n) processing said projected laser error signal to control a wavefront phase of the secondary phase correction device means to null the wavefront phase of the compensated projected laser beam sample observed on said laser wavefront sensor means.

An improvement to a compensated laser beam projection system, which includes a laser transmitter which produces a laser beam, and in combination with a beacon beam which is received, a compensated laser beam projection system having:

• an aperture sharing element which receives and splits said laser beam from said laser transmitter to produce an outgoing laser beam and a sample beam, said aperture sharing element receiving and reflecting a conjugated sample beam, said aperture sharing element also passing said beacon beam through it;
• a retro-reflector array which receives said sample beam from said aperture sharing element, said retro-reflector array producing a conjugated sample beam by reflecting said sample beam while conjugating errors in said sample beam, said retro-reflector array sending said conjugated sample beam back to said aperture sharing element;
• a means for measuring a wavefront phase of said conjugated sample beam and a wavefront phase of said beacon beam, said measuring means receiving said conjugated sample beam and said beacon beam from said aperture sharing element;
• and a primary phase correction device means that functions to receive said outgoing laser beam from said aperture sharing element, said primary phase correction device means further functioning to adjust said outgoing laser beam so that it becomes a conjugate of said beacon beam by adjusting said outgoing laser beam to remove any wavefront phase differences between said outgoing laser beam and said beacon beam;
• wherein the improvement comprises:
• a) a secondary phase correction device means that functions to apply a secondary wavefront phase to said conjugated sample beam and said beacon beam from said aperture sharing element before said conjugated sample beam and said beacon beam are received by said measuring means;
• b) said measuring means further functioning to provide a beacon beam output signal by measuring said wavefront phase of said beacon beam;
• c) said measuring means further functioning to provide a projected laser beam output signal by measuring said wavefront phase of said projected laser beam;
• d) said primary phase correction device means further functioning to receive said beacon beam output signal from said measuring means, said primary phase correction device means further functioning to null said wavefront phase of said beacon beam measured by said measuring means;
• and
• e) said secondary phase correction device means further functioning to receive said projected laser beam output signal from said measuring means, said secondary phase correction device means further functioning to null said wavefront phase of said projected laser beam measured by said measuring means.

A compensated laser beam projection system having:

• a) a laser transmitter which produces a laser beam;
• b) a beacon beam which is received;
• c) an aperture sharing element means that functions to receive and split said laser beam from said laser transmitter to produce an outgoing laser beam and a sample beam;
• d) said aperture sharing element means further functioning to receive and reflect a conjugated sample beam, said aperture sharing element means further functioning to pass said beacon beam through it;
• e) a conjugation means which functions to receive said sample beam from said aperture sharing element means, said conjugation means further functioning to produce a conjugated sample beam by reflecting said sample beam while conjugating errors in said sample beam, said conjugation means further functioning to send said conjugated sample beam back to said aperture sharing element means;
• f) a means for measuring a wavefront phase of said conjugated sample beam and a wavefront phase of said beacon beam, said measuring means receiving said conjugated sample beam and said beacon beam from said aperture sharing element means;
• g) said measuring means further functioning to provide a beacon beam output signal by measuring said wavefront phase of said beacon beam;
• h) said measuring means further functioning to provide a projected laser beam output signal by measuring said wavefront phase of said projected laser beam;
• i) a primary phase correction device means that functions to receive said outgoing laser beam from said aperture sharing element, said primary phase correction device means further functioning to adjust said outgoing laser beam using information from said beacon beam output signal and/or said projected laser beam output signal so that it becomes a conjugate of said beacon beam by adjusting said outgoing laser beam to remove any wavefront phase differences between said outgoing laser beam and said beacon beam;
• and
• j) a secondary phase correction device means that functions to apply a secondary wavefront phase using information from said beacon beam output signal and/or said projected laser beam output signal to said conjugated sample beam and said beacon beam from said aperture sharing element before said conjugated sample beam and said beacon beam are received by said measuring means.