Abstract: A method and system for automatically aligning a high power laser. The high ower laser train includes an unstable resonator cavity and two turning mirrors to direct the pointing of the output laser beam. The autoalignment system is designed to perform two alignment tasks, the maintenance of output beam pointing stability and the establishment of resonator cavity mode control, by precisely adjusting the orientation of the end mirrors of the resonator cavity and the two turning mirrors. A HeNe laser, located at the output end of the high power laser train, propagates an alignment beam back along the laser train, parallel to the high power laser train. The alignment beam is divided into two separate alignment beams by means of a mirror splitter. One of the beams is directed on an optical alignment path which includes the two turning mirrors and is delimited by two null position detectors, one on an end mirror of the resonator cavity and one at the output end of the high power laser train.

Abstract: A method and system for automatically aligning a high power laser utilizing diffraction ruled reflection grating to sample the laser beam. A tiltable beam alignment mirror directs a laser beam in a path incident to the reflection grating which separates the incident beam into a reflected beam and first and second order diffraction beams. A tiltable distortion compensation mirror is positioned in the path of the two diffraction beams. Two auxiliary fixed mirrors are positioned such that the diffraction beams will reflect a predetermined number of times off the distortion compensation mirror prior to reflecting toward respective null position detectors. Error signals from these detectors are translated, in accordance with certain optical and mathematical relationships, into angular adjustments to the two tiltable mirrors, thereby compensating for the thermal distortion of the reflection grating and aligning the output laser beam.