Particle sizing with a simple differential light-scattering photometer: homogeneous spherical particles

Area of Science:

• Optics and Photonics
• Materials Science
• Analytical Chemistry

Background:

• Accurate particle size analysis is crucial in various scientific fields.
• Traditional methods can be complex or limited in resolution.
• Light scattering offers a non-invasive technique for particle characterization.

Purpose of the Study:

• To design and validate a simple yet effective light-scattering photometer.
• To measure the angular intensity distribution of polarized laser light scattered by particles.
• To enable accurate particle sizing of micrometer and submicrometer samples.

Main Methods:

• Development of a novel light-scattering photometer utilizing an ellipsoidal reflector.
• Collection and focusing of He-Ne laser-scattered light onto a photodiode array.
• Application of Mie scattering theory, reformulated for apparatus-specific corrections.

Main Results:

• Experimental data successfully obtained for monodisperse latex spheres of varying sizes.
• Scattered light intensity measurements showed good agreement with theoretical predictions.
• The instrument demonstrated capability for reliable particle sizing.

Conclusions:

• The designed photometer is a viable tool for particle size analysis.
• The reformulated Mie theory accurately interprets the experimental scattering data.
• This apparatus facilitates precise characterization of micrometer and submicrometer particles.