Optical Measurement of Large Sphere Diameters by means of Scattering

A simple method is demonstrated to determine the diameters of dielectric spheres from 0.2 to 1.0 mm by observing the scattering of visible light. Theoretical calculations show that there is an approximately linear relationship between the size of the scattering sphere and the number of maxima and minima in the scattered field as a function of angle when the radius in the 200-1000-wavelength region.