METHOD MEASURING VELOCITY OF DIFFUSING MICROOBJECTS Russian patent published in 2004 - IPC

FIELD: speckle optics, specifically, measurement technology. SUBSTANCE: invention can find use for measurement of velocity of lateral translation of diffusing objects, microobjects included, capillary flow of liquid containing diffusing particles in particular and for determination of longitudinal coordinates of moving diffusing objects in biology, medicine, mechanical engineering and other fields of science and technology. Microobject is irradiated in turn with coherent radiation perpendicular to direction of velocity by two coaxial beams which neck planes are located at specified distance one from another. Photodetectors are placed in field of scattered radiation in far region of diffraction in plane perpendicular to axes of beams. Relative time delay of signals of photodetectors are established for cases of illumination of object by each beam individually. Velocity of diffusing object and its longitudinal coordinate are found by difference of relative time delays. EFFECT: increased measurement accuracy of velocity of diffusing object in absolute values with allowance for direction of motion, microobject included, achieved thanks to elimination of systematic error coupled to impossibility of precise longitudinal localization of object with reference to measuring device from velocity measurements. 3 dwg