Measuring particle size distribution

摘要

A method and apparatus for determining the particle size distribution of particles in a mass of a granular substance. The particles are caused to fall in a stream of separate particles past an irradiated screen, and an instantaneous television picture is taken of the particles and the projected images of the particles are used to measure the projected areas of the particles. Using these areas assuming the average shape of the particles to be substantially a rotational ellipsoid and using a coefficient according to the average configuration of the particles, the particle sizes and their distribution in the mass of particles are calculated.