Abstract: A series of taps are created within an acousto-optic cell by imaging an array of LEDs within the cell. The illuminated tap regions are selectively changed by energizing selected LEDs. The electrical input signal produces a travelling acoustic wave within the cell and when the wave crosses illuminated tap regions, electrical output signals are produced having delays proportional to the positions of illuminated LEDs in the array. The magnitude of the output signal is proportional to the LED light intensity which is varied to produce a weighted output signal.

Abstract: A first signal acousto-optic (AO) cell together with a first signal source for injecting a first signal therein is disclosed along with a second AO cell together with a second signal source for injecting a second signal therein, to be correlated with the first signal. A first plus one diffracted order beam emerges from the first cell and is directed at a second cell to produce second and third plus one diffracted order beams which overlap and which produce an interference pattern that is focused on a photodetector array which determines the degree of correlation between the first and second signals. A Dove prism is employed between the cells to cause the second and third beams at the array to be counter-propagating and to control the spatial frequency of the interference pattern produced by these beams.