Multiple light scattering is an important issue in modern laser diffraction
spectrometry. Most laser particle sizers do not account for multiple light
scattering in;a disperse medium under investigation. This causes an undere
stimation of the particle sizes in the case of high concentrations of scatt
erers, The retrieval accuracy is improved if the measured data are processe
d with multiple-scattering algorithms that treat multiple Light scattering
in a disperse medium. We evaluate the influence of multiple light scatterin
g on light transmitted by scattering layers. The relationships among differ
ent theories to account for multiple light scattering in laser particle siz
ing are considered. (C) 2001 Optical Society of America.