Diagnostics of the presence of solid particles in aqueous aerosol droplets by their interference pattern

We have experimentally studied the influence of solid impurity particles present in aqueous aerosol droplets on their interference patterns. The interference patterns were studied with the aid of a Nd:YAG laser and CCD video camera. The radii of droplets in the aqueous aerosol ranged within 10–140 $\mu$m. Solid particles of four materials were introduced in the aerosol to a mass concentration of 0.003–1 g/L. Specific types of interference patterns determined by the presence of solid impurities in droplets are described, and the influence of impurity type and concentration on the integral characteristics of these patterns (number and type of images) is established. A new approach to determining the impurity concentration and particle dimensions in aerosols is proposed based on the analysis of their interference patterns.