What is the effect of refractive index in particle size measurement?

Especially for particles with very small diameters, the scattering phenomenon is greatly influenced by their refractive index.

In devices that measure the light scattering of particles, such as laser diffraction and scattering particle size distribution measurement devices, the refractive index of the dispersion medium and the particles, the particle diameter, and the wavelength of the light source are important factors. As an example, the scattering light intensity due to the difference in refractive index is shown in the diagram with the particle size parameter α = πD/λ (D: particle diameter, λ: wavelength of the light source) as a variable. The scattering phenomenon changes sensitively with particle diameter and refractive index, as shown in the diagram. For large particles with low translucency, diffraction phenomena dominate the scattering phenomenon, and the influence of the refractive index is minimal. However, for small translucent particles, various phenomena that change with the refractive index, such as reflection and refraction at the particle-dispersion medium interface, light attenuation within the particle, and reflection at the inner surface of the particle, have a significant impact. *For more details, please refer to the related links or feel free to contact us.*

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