イメージスキャナとマイクロコンピュータを用いた粒子の形状解析 : 凝集エアロゾル粒子への適用

抄録

Algorithms are presented for feature extraction of geometrical shape of particles. The system consists of microcomputer, and an image scanner which scans the micrograph of particles and transmits the compressed image data. Methods for shape analysis are 1) calculation of fundamental particle shape parameters (Feret diameter, area, perimeter, first moment, second moment), 2) fractal analysis, 3) opening method and 4) separation of circular primary particles from an agglomerate. Connectivity of particle boundary is recognized for five cases (continuation, termination, creation, split and merge), and fundamental shape features are calculated according to it. Validity and accuracy of these methods are examined by comparing the calculated and theoretical shape parameters for standard figures. A new index is proposed for the structuring element number of two-dimensional particle shape in opening analysis.
 These methods are applied to the shape analysis of agglomerated aerosol particles generated from an electric furnance and by CVD method, and it is shown that the fractal dimension as a particle distribution is useful for quantitative description of shape feature.