Influence of the angular light scattering measurement uncertainly on the particle-size distribution

The determination of the spherical particle-sizes in colloidal suspension by Angular Light Scattering presents a lot of advantages, i.e.: the relative simplicity of the experimental installations, and its non-destructive character. The intensity of the scattered light is related with the radius of a particle by Mie Theory. However, the dynamic characteristic of the measurements establish a variations of the scattered intensity with the time which it has not considered. In the case of the particle suspended in water, the intensity of the scattered light measured in each angle theta is the superposition of the scattered intensity for each particle. In consequence, the intensity of the light scattered will be related with a particle-size distribution function, that in this work is assumed as a delta function. Then, the dependence of the scattered intensity with time is studied evaluating the variation of the center point of delta function with time taking account to the standard deviation of angular scattered intensity. The accuracy of the method is evaluated throw the deviation of the particle-size distribution taking in to account the standard deviation of the angular intensity scattered by calibrated particles of latex. A correct evaluation of the dynamic method is realized in terms of the static approach.