Rigorous theoretical framework for particle sizing in turbid colloids using light refraction
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Updated: Jun 27, 2026

Measurement of Particle Size Distribution in Turbid Solutions by Dynamic Light Scattering Microscopy
Published on: January 9, 2017
Augusto García-Valenzuela1, Rubén G Barrera, Edahí Gutierrez-Reyes
1Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Apartado Postal 70-186, Distrito Federal 04510, México. augusto.garcia@ccadet.unam.mx
Abstract:
Using a non-local effective-medium approach, we analyze the refraction of light in a colloidal medium. We discuss the theoretical grounds and all the necessary precautions to design and perform experiments to measure the effective refractive index in dilute colloids. As an application, we show that it is possible to retrieve the size of small dielectric particles in a colloid by measuring the complex effective refractive index and the volume fraction occupied by the particles.
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