Study on laser scattering depolarization characteristics of typical aerosol particles

In order to study the transmission characteristics of polarized light in the atmosphere under the influence of multiple factors, the polarization Monte Carlo model is established based on Mie scattering theory and Stokes vector, and the scattering depolarization of photons in the atmosphere is calculated and analyzed. The effects of four typical aerosol particles with different optical depth on the forward scattering of 1064 nm narrow-pulse laser with different polarization states are systematically analyzed. The results show that with the increase of optical depth, the degree of polarization of several polarized light decreases to varying degrees. Among them, circularly polarized light has better polarization retention than linearly polarized light, and dust particles have the most significant depolarization characteristics than water soluble particles, sea salt particles and soot particles. Through the calculation and analysis of the variation of Stokes parameters of forward scattering light with the increase of optical depth, it is found that the polarization angle of circularly polarized light scattered by medium is not easy to change than that of linearly polarized light. At the same time, the model results also show that the scattering medium with larger particle size has more significant depolarization characteristics, and the circularly polarized light is insensitive to the change of particle size in the scattering process. The research results of this paper can provide reference for the application of narrow-pulse polarization laser in laser remote sensing, laser guidance, laser communication and laser radar, and provide data basis and theoretical guidance for the development of narrow-pulse polarization laser equipment.