A quasi real-time autocorrelator for light scattering experiments

Abstract

A multibit, minicomputer-based digital autocorrelator with a large number of delay channels is described. Due to a novel operating principle, quasi real-time behaviour is achieved at low count rates. Therefore no time is wasted in situations where the time needed for an experiment is most critical. Sample times range from 10 ns to 168 ms, the counting capacity may be set from one to five bits per sample time, the total delay is between 4000 and 760 channels. Signal utilisation and accuracy of the instrument are discussed and compared with an ideal real-time autocorrelator.