Optical turbidity and refraction in a dispersion of spherical colloidal particles

Abstract

In addition to causing optical turbidity, a dispersion of spherical colloidal particles also affects the phase of light transmitted through it. This phase change is shown to be related to a new parameter P_sca which is the refraction counterpart per particle to Q_sca, the conventionally defined scattering efficiency. Mie theory calculations of P_sca and Q_sca are compared and a method suggested for measuring both the size and the relative refractive index of a spherical colloidal particle in a dilute dispersion.