8 May 2012 A flexible tool for simulating the bulk optical properties of polydisperse suspensions of spherical particles in an absorbing host medium
Author Affiliations +
Abstract
In this study, a tool was developed to calculate the bulk optical properties for systems consisting of an absorbing medium and polydisperse spherical particles that can scatter and/or absorb. The developed tool is based on the Mie-theory for monodisperse-spherical absorbing and scattering particles in vacuum. First, the original Mie-theory was expanded to also include physical (real part of refractive index) and chemical (aborption, imaginary part of refractive index) information of the host medium. Secondly, the polydispersity of the spherical particles was taken into account. Since particle size distributions (PSD) are typically continuous distributions and Mie-scattering properties can only be calculated for a monodisperse system, the PSD is fractionated and Mie-scattering properties were calculated for each fraction. These Mie-scattering properties are then combined with the weight for each fraction to derive bulk optical properties. As the number of fractions is unknown and needs to be optimized for each calculation, the developed tool keeps on fractionating until the desired properties (μabs, μsca and P11(cos(θ))) converge to stable values. This flexible tool allows for the simulation of the bulk optical properties for a wide range of wavelengths, particle volume fractions, complex refractive indices of both the particles and the medium and PSD's based on normal, lognormal, gamma, bimodal and custom defined functions. This code was successfully validated for the case of a lognormal PSD of scattering spheres in vacuum by comparing the simulated values to those reported in literature. The main novelties of the developed program are the extension of Mie-theory simulations to the case of polydisperse scattering particles in absorbing media and the automatic optimization of the number of PSD fractions needed to converge.
© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
B. Aernouts, Ro. Watté, J. Lammertyn, W. Saeys, "A flexible tool for simulating the bulk optical properties of polydisperse suspensions of spherical particles in an absorbing host medium", Proc. SPIE 8429, Optical Modelling and Design II, 84290R (8 May 2012); doi: 10.1117/12.922721; https://doi.org/10.1117/12.922721
PROCEEDINGS
12 PAGES


SHARE
Back to Top