Measuring Particle Size Distribution by Digital Image Processing with Inverse Fourier-Bessel Transformation

An analytical approach based on digital image processing is proposed for measuring the size distribution of circular particles. From an analogy with the light diffraction pattern of a circular aperture, a reduced spectrum of the particles' image can be obtained using a two-dimensional fast Fourier transformation. The reduced spectrum, which is equivalent to the diffraction pattern, is analyzed using the theory of inverse light scattering to evaluate the size distribution of the particles. The usefulness of this method is confirmed not only in binary images but also in gray-scale images created by computer simulation.