Modified conventional plane-wave scattering approach to estimate performance characteristics of laser particle-size analysers

摘要

A technique is derived for the rapid engineering simulation of the influence of the main instrumental parameters of a laser particle-size analyser on its response function and other main performance characteristics. The technique is based on the modified conventional (classical) plane-wave approach. From the methodological point of view, this method incorporates a set of nondimensional coefficients describing the change of the amplitude, duration and shape of a pulsed signal for different particle trajectories in a Gaussian beam with a circular or elliptical cross-section. The above-mentioned performance characteristics as well as the distortion of the signal shape caused by the bandwidth limitation of a photodetector are investigated taking into account the nondimensional coefficients. It was shown that the technique is valid for the modelling of measurements of attenuation and/or near-forward scattering by single particles in the broad practical range of particle diameters. Correctness of the modified technique has been confirmed experimentally and theoretically by comparison with the exact generalized Lorenz-Mie theory. Application of the technique for the rapid investigation of performance characteristics of laser particle-size analysers is illustrated. [References: 20]