Patent ID: 6016194
Filing Date: 2000-01-18
Classification: G01N

Abstract:
An optical scattering method of determining a size of a particle, comprising:injecting into a view volume having a longitudinal axis target particles having an injection velocity that varies as a function of a position along the longitudinal axis;propagating coherent radiation having an intensity along the longitudinal axis of the view volume, the radiation exiting the view volume including an unscattered portion of the radiation unscattered by the target particles and a scattered portion of the radiation scattered by the target particles;detecting with collection optics and an array of photo-detector elements the scattered portion of the radiation, each photo-detector element sensing radiation scattered from one of the positions along the longitudinal axis of the view volume and generating a signal having a magnitude that depends on the intensity of the radiation, the size of the target particle, and the injection velocity of the target particle; andadjusting a gain associated with each photo-detector element to compensate for the particle injection velocity variations along the longitudinal axis of the view volume so that a gain-adjusted magnitude of each signal represents substantially the size of the particle.