To Test The Light-scattering Properties, The Typical Laser Radar Target

The targets'backscattering characteristics affect the performance of the laser radar directly, and also the research of these characteristics is very important to the system optimization of the laser radar or the laser rangefinder. On the basis of previous theories, we deduced the backscattering light's depolarization formulations of Gaussian rough surface, and analyzed the depolarization curves of both metal and non-metallic Gaussian rough surface when P-polarized light and S-polarized light incidence them. Then the experiments on the targets' backscattering characteristics were conducted. These experiments mainly measured the Stokes parameters of backscattering lights and those devices of experiments worked in 905nm band. We mainly compared both P-polarized light and S-polarized light incidences frosted glass,180# sandpaper,400# sandpaper,600# sandpaper and two nickel alloy plates with different roughness to analyze the effect of backscattering characteristics on different material, roughness and also different incident angle and different polarization light. It is obviously that the backscattering light characteristics are different between those targets' surface. For the same surface, the polarization degree of backscattering light is higher when P-polarized light incidences. For the same material targets, the polarization degree is higher when roughness is lower, but when the surface's RMS height is far greater than the wavelength of incident light, the polarization degree will improve. At a small angle of incidence, nickel alloy plates have strong polarization characteristic. The polarization degree and the intensity of sandpaper's backscattering light does not change significantly when the incident angle increases, so the sandpaper can be seen as a ideal diffuse material.This paper did a preliminary summary of light's backscattering characteristics of several groups of different materials, different roughness surfaces, also the characteristics and the theories math pretty well. The data provide an understanding of the light's backscattering characteristics of rough surface, and have a certain reference value on the research of laser detection.