Open AccessSimultaneous retrieval of the complex refractive index and particle size distribution
Author(s) -
Yukun Ren,
Hong Qi,
Qin Chen,
Liming Ruan,
HePing Tan
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.019328
Subject(s) - refractive index , optics , transmittance , collimated light , materials science , wavelength , particle swarm optimization , particle size , particle size distribution , radiative transfer , physics , laser , mathematics , mathematical optimization , chemistry
A secondary optimization technique is proposed that allows the complex refractive index and particle size distribution (PSD) to be retrieved simultaneously by using the diffuse transmittance (T), diffuse reflectance (R), and collimated transmittance (T(c)) of a 1-D spherical particle systems as measured values. In the proposed method, two 1-D experimental samples of different thicknesses were exposed to continuous wave lasers of two different wavelengths. First, T, R, and T(c) were calculated by solving the radiative transfer equation. Then, the complex refractive index and PSDs were retrieved simultaneously by applying the inversion technique, quantum particle swarm optimization. However, the estimated results of the PSDs proved to be inaccurate. Hence, a secondary optimization was performed to improve the accuracy of the PSDs on the basis of the first optimization process. The results showed that the proposed technique can estimate the complex refractive index and particle size distribution accurately.