A two dimensional image correlator based on acousto-optic (AO) and charge coupled devices (CCDs) is described that can be built with existing technology to provide 1000 frames per second operation. In recent years, architectures have been developed that perform the two dimensional correlation utilizing one dimensional input devices. The input scene is loaded into the acousto-optic device (AOD) one line at time. This line is then correlated against all of the rows of a reference template introduced into the optical system using a one dimensional array of LEDs or laser diodes. However, it generally takes a much greater time to load the AO cell than it does to process the information. This latency time severely limits the maximum throughput rate of the processor. This paper introduces a new acousto-optic correlator implementation that overcomes this bottleneck so that processing can occur close to 100% of the time. A grayscale image correlator is proposed that can be built using present technology that can realistically achieve throughput rates on the order of lO12 operations per second. This translates to over 1000 correlations per second for input scenes with dimensions of 512 x 512 pixels and reference templates of size 64 x 64 pixels.
Perry A. Molley, Perry A. Molley,
"Acousto-optic image correlator with a throughput rate of 1000 templates per second", Proc. SPIE 1295, Real-Time Image Processing II, (1 September 1990); doi: 10.1117/12.21227; https://doi.org/10.1117/12.21227