Abstract

A demonstration of a real-time image correlator based upon acousto-optic and charge-coupled devices will be presented. This architecture performs the two-dimensional correlation utilizing one-dimensional input devices. Each input image line is read into the system one line at a time using an acousto-optic device (AOD). The reference templates are stored in an electronic memory and introduced into the optical system in row parallel using a one-dimensional laser diode array. As the information propagates down the length of the AOD it is correlated against all of the rows of the reference template; the result accumulates on a 2-D charge-coupled device (CCD). The correlation in the vertical direction is accomplished by operating the CCD in a shift-and-add mode. The demonstration involves tracking a moving grayscale object using a video cassette recorder as the input image source. The ability to rapidly correlate with multiple templates will also be demonstrated. The optics are mounted inside a 12 in. × 15 in. × 6 in. enclosure. The memory and control electronics are housed in a single VME card cage.

© 1990 Optical Society of America