Coherent Optical Method for Studies of Nanoscale Objects in Liquid Media Based upon Spatial Averaging of Data

摘要

Correlation method for processing dynamic light scattering patterns observed when laser radiation passes through liquid media was developed. The method is based on procedure of spatial averaging of the data contained measured values of correlation functions of intensity of light scattered by moving small particles. The method allows one to measure particles diameters from 30 to 750 nm with measurement error less then 10%. The method makes it possible to decrease correlation functions measurement time down to 1 ms and provides opportunity to carry out measurements for different scattering angles simultaneously. The method offers a way of recognizing speckle pattern transformations caused by harmonic, translatory and Brownian motions of particles, and allows one to register influence of uncontrolled forces such as monochromatic and wideband acoustic fields upon particles size measurements results.