随机粗糙面穆勒矩阵的数值分析

Numerical Analysis of Mueller Matrix for Random Rough Surfaces

穆勒矩阵反映了物体对光波偏振特性的影响,包含大量的物体表面信息。采用基尔霍夫近似法分析了二维随机粗糙面的散射场和散射穆勒矩阵,数值模拟了入射角和相对粗糙度变化时铜、铁、镍、玻璃、铌酸锂的散射穆勒矩阵。仿真结果表明,金属和电介质的穆勒矩阵存在明显差异:随着入射角的增大,金属和电介质的m_(01)、m_(10)、m_(22)、m_(33)参数变化幅度分别小于30%和大于80%;随着相对粗糙度的增大,金属和电介质的m_(00)、m_(11)、m_(22)、m_(33)参数变化幅度分别超过60%和小于20%;金属的m_(23)、m_(32)参数随入射角的增大而增大,随着相对粗糙度的增大而减小,而电介质的m_(23)、m_(32)参数始终为0。这些差异可用于识别金属和电介质,也为物体表面粗糙度的测量提供了一定参考。

The Mueller matrix describes the influence of an object on the polarization of optical waves.It has various information about the object surface.In this paper,the scattering field and the scattering Mueller matrix of twodimensional random rough surfaces are analyzed using the Kirchhoff approximation method.The scattering Mueller matrices of copper,iron,nickel,glass,and lithium niobate are numerically simulated using the incidence angle,and the relative roughness is changed.With the increase of the incident angle,the m_(01),m_(10),m_(22),and m_(33) parameters of metals and dielectrics vary by less than 30% and greater than 80%,respectively.The m_(00),m_(11),m_(22),and m_(33) parameters of metals and dielectrics vary by more than 60% and less than 20%,respectively.Further,the m_(23) and m_(32) parameters of metals are increased as the incident angle increases,and are decreased as the relative roughness increases,whereas the m_(23) and m_(32) parameters of the dielectric are always 0.The differences can be used for identifying metal and dielectric and provide some reference to the measurement of object surface roughness.