Patent ID: 6100976
Filing Date: 2000-08-08
Classification: G01N

Abstract:
A method of determining a particle size using dynamic light scattering, wherein is provided a sample containing a plurality of particles, comprising the steps of:(a) directing a laser light beam at the sample, thereby creating a speckle field containing at least a multiply scattered signal and a singly scattered signal;(b) orienting a first detector so as to detect a predetermined portion of the speckle field;(c) orienting a second detector so as to detect substantially the same predetermined portion of the speckle field, said second detector being aligned at a predetermined small angle with respect to said first detector;(d) simultaneously detecting the predetermined portion of the speckle field within said first detector and said second detector, thereby creating a first detector signal and a corresponding second detector signal;(e) performing steps (b) to (d) at a plurality of different predetermined small angles, thereby producing a plurality of first detector signals and a corresponding plurality of second detector signals; and,(f) determining an estimate of the particle size using said plurality of first detector signals and said corresponding plurality of second detector signals.