Tracking speckle patterns with optical correlation

摘要

It has been shown that tracking small particle motion can be accomplished by tracking the speckle pattern is produces. This paper describes various methods of real-time tracking of speckle patterns obtained from ultrasonic flow imaging of blood and tissue motion using optical correlation. Results obtained from a gray scale joint transform correlator utilizing a twisted nematic liquid crystal spatial light modulator and from Sandia Lab's acousto-optical correlator are presented. The experimental results demonstrate the feasibility of real-time tracking with accuracy comparable to that of template matching algorithms currently being implemented in digital hardware.