粗糙表面激光散射特性的理论研究

Theoretical Study of Laser Scattering from Rough Surfaces

用矢量微扰动方法分析激光束在粗糙表面上散射的分布特性。详细讨论高斯光束的角谱和适用于准直激光束散射问题的波前分割概念认为，当用入射总功率作归一化因子时，准直粗激光束散射可近似地作为平面波处理，而细激光束散射则与平面波存在很大的差异。利用所得结果讨论了一维粗糙表面的激光隐身作用及椭圆偏振光入射时镜反射方向和后向散射场的偏振态。最后介绍两种线偏振光在粗糙表面上散射分布的差异。实验验证了主要结论。

The vector small perturbation theory based on Ewald Oseen extinction theorem is developed to study the laser scattering from rough surfaces. Angular spectrum of the Hermite Gaussian beam is analysed in detail and a concept of wave front cutting apart is discussed. This concept leads to the consideration that the scattering of collimated laser beams can be approximately dealt with as that of plane wave if the total incident power is used as the normalization factor, but the slender beam scattering is quite different from the plane wave. Using the obtained results, it is discussed theoretically that the concealment of 1 D rough surfaces from active detection and the scattered polarization at specular and back direction under the illumination of a ellipse polarized beam. Then distribution difference of the scattered light of vertically and horizontally polarized laser beam is introduced. The dominant conclusions are verified.