| 摘要 |
An associative memory system is provided which is a hybrid of optical and electronic components. In the preferred embodiment, a Fourier transform hologram is used to convolve a reference beam with correlated input images and stored object images. An electronic iteration loop is provided which is used to derive an enhanced reference beam for use in matching and enhancing the associative memory of the hologram with the object input plane image. The iteration loop of electronic components comprises a vidicon which receives the correlation plane image and provides that image in the form of an electronic signal to an electronic thresholding device or image processor. The image processor is capable of viewing the data at the rate of 30 frames per second and is used in the preferred embodiment to threshold the data with reference to the greatest amplitude portion of the correlation spot provided to the vidicon. After the electronic threshold has processed the signal, an improved signal is provided to the cathode ray tube screen. This processed signal is used to phase-modulate a projection light readout beam through use of a liquid crystal light valve. A polarizing beam splitter converts the phase modulation of the readout beam to an amplitude modulation wherein an enhanced reference beam is derived which is processed back to the hologram for readout at the output plane of the system. In this manner a variable-gain fast response electronic and optical component hybrid is provided for use as an associative memory.
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