Scattering of an arbitrary shaped object by using vectorial complex ray model

Abstract

Vectorial complex ray model has been developed to describe the scattering of smooth surface object of arbitrary shape. In this model, the property of a wave — curvature of wavefront is integrated in ray model, such that all waves are described as vectorial complex rays of five parameters: amplitude, phase, direction of propagation, polarization and curvature matrix of its wavefront. At each interaction of a ray with the surface of the object, the ray direction is determined by the vector Snell law, the divergence or convergence of the wave is calculated by the wavefront curvature (WFC) and the phase shift due to focal line is evaluated according to CWF. The total scattered field is the superposition of the complex amplitude of all orders of the rays emergent from the object. Thanks to the simple representation of the wave, this model is very suitable for the description of the interaction of an arbitrary wave with an object of smooth surface and complex shape. The applications of the model to 2D scattering of a plane wave by an infinite elliptical cylinder and a spheroid particle are presented. The particle can be absorbing and its refractive index can also be less than unity.