Apparatus for detecting an output image of an optical correlation

摘要

A coherent optical correlation system produces an output signal in the form of a beam of light which if focused onto an output plane would produce a spot of light somewhere in that output plane. To detect the position that spot would have in the output plane, the output beam is formed into two parts by a beam splitter and each part is passed through a multiple image diffraction grating arranged mutually at right angles to thereby form a linear array of spots parallel to the x and y axes of a correlation output plane. Each series of output spots illuminates a photodiode in a linear diode array thereby identifying the x and the y coordinates of a correlation image.