Photopolarimetric properties of analytic models of some biological particles with irregular shape

We provide analytic descriptions of the morphologies of some biological particles: Sporisorium cruentum spores, Aspergillus terreus spores, and erythrocytes. We use the T-matrix extended-boundary-condition method to calculate the scattering properties of these particles. It is found that the morphology of A. terreus spores reveals an unusually wide negative polarization branch with two minima near large scattering angles, and that of S. cruentum spores do not display a negative polarization branch at all. We show that for unrealistically small size parameters, a simple cylinder has many of the same qualitative scattering properties of the much more complicated model of erythrocytes; however, as the particle size is made more realistic, very large differences appear in the scattering from these particle systems.