| 摘要 |
An optical system (10) for correcting wavefront aberrations of an optical beam (12). The beam (12) is received by an entrance pupil (14), where a portion of the beam (12) at the entrance pupil (14) is coupled off of the main beam (12) to be used as a reference beam (22). The reference beam (22) is taken from a small enough portion of the main beam (12) so that the temporal coherence of the reference beam wavefront is substantially in phase. The reference beam (22) is amplified by a coherent reference amplifier (24), expanded and collimated. The main beam (12) and the collimated beam (28) are applied to a beam splitter (16) that splits the main beam (12) and the reference beam (22) into two separate beam paths, where the main beam (12) and the reference beam (22) traveling along a common path are coupled together. One optical path from the beam splitter (16) is applied to a detector array (32) and the other optical path from the beam splitter (16) is applied to a light valve (40). Those portions of the main beam (12) that are more than 90° out of phase with the reference beam (22) destructively interfere at the detector array (32). The outputs of the detectors in the array (32) are measured by threshold electronics (36). The threshold electronics (36) cause the light valve (40) to attenuate the portions of the beam on the other path that are the destructively interfering portions of the main beam (12) and the reference beam (22) so those portions do not pass through the light valve (40). Therefore, only those portions of the main beam (12) that are substantially in phase with the reference beam (22) continue on through the receiver optics.
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