INSTRUMENT FOR MEASURING PARTICLE SIZE DISTRIBUTION

摘要

PROBLEM TO BE SOLVED: To provide the so-called diffraction/scattering type measuring instrument for measuring a particle size distribution sharply reduced in cost as compared with a conventional one and prevented from the lowering of measuring precision though made compact. SOLUTION: The instrument for measuring particle size distribution is equipped with a light source 2 for emitting fundamental light L displaying a small diameter direction HD and a large diameter direction HV on its cross section, the condensing lens 6 arranged on the optical axis of the fundamental light L and interposed between the light source 2 and a group of particles C to be measured and a photodetector 4 for detecting the intensity and anglular distribution of diffracted/scattered light L'. The diameter D6 of the lens 6 is made larger than the small diameter dimension DS of the cross section of the fundamental light and smaller than the large diameter dimension DL thereof in a lens-installated region and the light detecting surface 4a of the photodetector 4 is set to a position avoiding the vicinity of the axial line AV of the large diameter direction in the cross section of the fundamental light. COPYRIGHT: (C)2004,JPO&NCIPI