| 摘要 |
A lensless recognition system including a hologram having interference patterns therein corresponding to known characters. The interference patterns are formed by a character beam which passes through a transparent mask of the character to be recorded and intersects a reference beam on a photographic plate. In the recognition process quasi-monochromatic incoherent illumination from an unknown character transmits through the hologram which is obtained by developing and bleaching the photographic plate. Correlated output signals of varying intensity are formed in the output plane at the locations occupied during the recording process by the transparent masks which most closely correspond to the unknown character. Each of a plurality of pinholes positioned at the locations corresponding to each mask transparency transmits the central value of a correlated output signal. A photodetector aligned with each pinhole senses the transmitted central value and produces a current signal that is processed in a postprocessor to provide an output signal that is indicative of the corresponding known character.
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