Abstract: The model of porous particles was built in this paper, and the optical properties of them were carried out utilizing discrete dipole approximation and Bruggeman effective medium theory for the number of air pockets from 49 to 299. After analyzing and comparing the scattering properties of porous particles obtained by two computing methods, we found that the effective medium theory has a good validity for the extinction efficiency, the absorption efficiency and the scattering efficiency when the number of air pockets less than a certain value, but not vice versa. While for the single-scattering albedo and the asymmetric factor, the effective medium theory always keeps a good validity in the research scope of this paper. The results also revealed that the inference of the doctor Michael about the validity of effective medium theory in light scattering of porous particles was not comprehensive.
