Effect of excess surface charges on optical measurement of sub-micron particles with different properties

摘要

The exploration of the optical properties of charged particles is essential for the optical detection of ultrafine particles. In this paper, the complex refractive index model and scattering model of spherical particles are re-established to make them suitable for both electrically neutral particles and charged particles. Taking pure-water droplets and salt-water droplets as examples, the effects of surface charge on the complex refractive index of non-dissipative particles and dissipative particles are discussed. On this basis, the effects of excess surface charge on the optical parameters of droplets, inorganic oxide particles and organic compound particles are discussed with three typical dissipative particles. Furthermore, it is confirmed that the effect of charge on particles with different properties is consistent.