Abstract
Light transmittance by clouds of small particles has long been used as a method to measure particle properties such as size or concentration. However, this application of light scattering has resulted in empirical data dependent on the specific instrument. Deviations from light extinction theory result when scattered light enters the detector, increasing the apparent transmittance. Previous studies of light extinction measurements have mainly considered error as a function of particle size with only limited analysis of polydispersed particle size distributions. The ratio of the expected extinction coefficient to the theoretical extinction coefficient is reported as a function of the log-normal size distribution parameters, geometric mass mean radius, and geometric standard deviation, for various detector acceptance angles.