Light scattering from a sliced target through use of the internal field of infinite cylinders: comparison between Mie theory and a sliced sphere.

Light scattering from a particle that can be sectioned into circular slices is calculated by performing a coherent integration of the internal field over the volume of the target. The internal field in each slice is taken to be the internal-field solution of an infinite cylinder of radius equal to the radius of the slice. It is shown that for a spherical scatterer with size parameters up to 1.4, the integration leads to results that are in good agreement with those predicted by the Mie theory. Thus, we show the remarkable result that the internal field from an infinite cylinder can reproduce scattering intensities for such a radically different shape as a sphere. This being the case, a wide variety of target shapes between a sphere and a cylinder should be open to evaluation by this technique. The approach also has the benefit of being computationally efficient, requiring a double integration of the internal field over a disk and then coherently adding these calculations. The computations demonstrated in this paper are performed relatively quickly on a computer such as the Macintosh Centris 650, and this efficiency allows us to obtain the scattered fields for many target shapes.