| 摘要 |
A signature is holographically recorded for correlation and parallel processing against a large library of signatures. A transient electrical signal produces a pressure wave in an optical wavefront modulator where it is frozen in position by a picosecond laser. The modulated wavefront is made to interfere at a hologram plane with a reference wavefront which is converging to a focal point behind the hologram plane. Because the holograms are of the Fresnel type, the hologram plane may be partitioned off and a library of signatures may be recorded on the same hologram plane and addressed simultaneously. After processing, the reference wave is removed and the optical wavefront modulator illuminated by a continuous wave coherent source. If a signature, recorded on the hologram, is placed in the optical wavefront modulator, then the reference wave for that hologram is reconstructed and detected to identify that signature.
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