Polarization of Dipole Scattering by Randomly Oriented Ellipsoids

摘要

Analytic formulas are derived for the Jones matrix and the Mueller matrix for dipole scattering by an ellipsoid and by a system of ellipsoids with totally random orientation. The scattering Mueller matrix by an ellipsoid as a function of ellipsoid orientation was simulated and showed complicated structure. The average Jones matrix for an ensemble of randomly oriented ellipsoids is proportional to the Jones matrix for a sphere. The averaging of the Mueller matrices washes away all the complicated structures and reduces to a simple Mueller matrix only a little more complicated than that for a sphere. The polarization of the dipole scattering by such ensemble depends on the scattering angle and the polarizability ratio ft of a single ellipsoid. Scattering in the direction perpendicular to the incident direction shows the largest effects on both linear polarization and depolarization, although it has minimal intensity. More anisotropy (larger β) of scattering particles results in larger depolarization.