Ray-wave approximation for calculating laser radiation scattering by a transparent dielectric spheroidal particle

A theoretical model is developed and an algorithm is proposed for calculating far-field light scattering by a transparent dielectric particle significantly larger than a wavelength. The accuracy of this algorithm is close to that of the discrete dipole approximation. The calculation time for this algorithm in the case of particles with the size parameter higher than 50 is much lower than that for the discrete dipole approximation. Scattering diagrams for spheroidal particles of different sizes, orientations and refractive indices are calculated. The proposed algorithm has a great potential for quick calculations of parameters of light scattering by large biological particles such as erythrocytes and their aggregates, bacteria, etc.