Research On The Property Of Near-field Light Scattering From Object And Coating

In this dissertation, the property of light scattering by coating layers is systematically investigated, and laser beam scattering by a complex object in near field is also studied. The main works and results are as follows:1. By use of one order multiple scattering theory, light scattering and reflection by a single coating layer is analyzed. The variance of radiation intensity, bidirectional reflection distribution function (brdf) and laser radar scattering cross section with coating layer parameters is given, with the effect of rough contrast on bidirectional reflection distribution function.2. Based on the radiation transfer equation, light scattering by coating layer is studied by using Monte Carlo method. A new improved Monte Carlo method is proposed considering reflection and transmission on the surface of coating layers and the effect of random rough surfaces. The method can simulate light scattering behavior on the condition of single layer and multiple layers, and preferably deals with reflection and transmission between layers, with a good agreement with literature results.3. Laser beam scattering by an object in near field is studied. First, base on the measure data, a mathematical description of the angular distribution of detonator laser beam is given. Secondly, by using the scattering characteristics of rough surface, the relation formula between received power and transmitted power of remote system for a facet is derived. Finally, the scattering power for a conductor sphere is computed.4. A simulative algorithm of laser beam scattering by an object in near field is given. Based on the algorithm, a simulative software is worked. And by using geometrical modeling and hiding, the received power of remote system for F16 airplane, as an example, is computed.