Patent ID: 7268874
Filing Date: 2007-09-11
Classification: G01F,G01N,G01P

Abstract:
1. A method of measuring properties of particles immersed in a body, comprising: the performing of a series of instantaneous acquisitions, wherein each acquisition comprises a) illuminating the body with a temporally coherent light beam of predetermined width D and predetermined wavelength λ, in order to generate scattered radiation by scattering interaction of the light beam with the particles, and b) detecting a plurality of values of the intensity of the total radiation coming from the body at a plurality of points simultaneously, the points being substantially on a plane at distance z from the body such that the points can receive the scattered radiation which comes from substantially all of the directions in which the particles are capable of scattering, and that each of the points receives the scattered radiation of a large number of particles, whereby a near field speckled image is created on said plane, corresponding to said plurality of intensity values, wherein said detecting step provides a digital image signal indicative of said near field speckled image, and processing of the digital image signals of the series of acquisitions by means of image analysis in order to determine size and motion properties of the particles correlated to said near field speckled image.