GRAIN SIZE DISTRIBUTION MEASURING DEVICE

摘要

A device for measuring grain size distribution H at high speed. An image input unit (1) produces a gray-scale image (IG) of a group of particles being inspected. The gray-scale image (IG) is then digitized by a digitizing unit (2) into a digital image (I). A multiple resolution approximation unit (3) performs a multiple resolution approximation based on a digital image (IB) and a maximum development number (MZ) to obtain approximated image series (IV[0], IV[1], ..., IV[MZ]). A particle separation unit (4) performs particle separation (particle expansion and particle nucleus extraction) based on the approximated image series (IV[0], IV[1], ..., IV[MZ]) and a separation parameter (PS) to produce a particle separation image (IS). Based on the particle separation image (IS), a grain size distribution measuring unit (5) determines an equivalent diameter of a circle corresponding to an area of each particle and employs it as the diameter of each particle. The diameters are converted into weight ratios, which are then summed up to obtain a grain size distribution (H). In this way the measurement of grain size distribution is carried out at high speed and with high precision.