摘要 |
A method for combining beams from multiple laser emitters, which may be optical fibers or bulk amplifiers, to form a composite output beam with desirable beam characteristics, as measured, for example, by Strehl ratio. Beams from the multiple emitters are interferometrically combined in the near field, and the phases of the beams are controlled to provide optimal phase coherence, and thereby to minimize losses. Various techniques are disclosed for controlling the phase angles of the emitted beams, using either a separate phase detector for each emitter beam, or a single detector for the composite output beam, or nulling detectors in spurious outputs from the beam combining optics. All of these techniques achieve an improvement in Strehl, largely because the interferometric combination of beams is independent of the array fill factor.
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