Investigation of low-angle laser light scattering patterns using the modified Twomey iterative method for particle...

Area of Science:

• Optical Physics
• Materials Science
• Computational Science

Background:

• Low-angle laser light scattering (LALLS) is used for particle size analysis.
• The Twomey iteration method is a standard algorithm for solving Fredholm integral equations.
• Direct application of the Twomey method to LALLS data is hindered by unstable kernel functions.

Purpose of the Study:

• To modify the Twomey iteration algorithm to address kernel instability in LALLS data.
• To evaluate the performance of the modified Twomey (MT) method for particle size distribution reconstruction.
• To compare the MT method against a conventional algorithm using simulations and experimental data.

Main Methods:

• Modification of the Twomey iteration algorithm to fit LALLS data.
• Computer simulations with mono-dispersion and log-normal particle size distributions (0.1–1000 μm).
• Experimental validation using polystyrene latex standards (0.081–1007 μm) and a 24-element detector array.

Main Results:

• The modified Twomey method successfully reconstructs particle size distributions for both log-normal and narrow distributions.
• Simulations and experiments demonstrate the MT method's robustness against noise.
• The MT method shows superior accuracy for narrow particle distributions compared to the conventional algorithm.

Conclusions:

• The modified Twomey method provides a robust and accurate approach for particle size analysis using LALLS.
• This modified algorithm overcomes limitations of previous methods, particularly for particles with narrow size distributions.
• The study validates the MT method's effectiveness through comprehensive simulations and experimental measurements.