LASER DIFFRACTION ANALYSIS FOR TWO-DIMENSIONAL MODEL PARTICLES PHOTOGRAPHED ON THE SLIDE FILM

Abstract

ABSTRACT In order to investigate the influence of particle parameters on the light diffraction pattern analysis, a model particle was prepared by photographing the round particles and the rectangular ones separately on the slide film, and experimentally analysed with the He-Ne Laser diffraction system. The parameters analysed in this experiment are size, concentration, and shape of the particle images photographed on the film. The analysis provided a good coincidence with the results of microscopic observations; the standard deviation was within 1–5 %. The influence of the particle size of the sample on the results evaluated is negligible or in the acceptable range of measurement error. The results of observation suggests that the lowest limit of particle concentration will be suggested not to be less than 2 % in order to eliminate any possible errors in analysing the intensity of the diffraction pattern of round particles. For rectangular particles which are homogeneously and randomly dispersed on the film, the equivalent size evaluated approachs only to the magnitude of the breadth of the particle.