Two methods for modeling the propagation of the coherence and polarization properties of nonparaxial fields

The propagation of nonparaxial, partially coherent fields may be modeled in many ways. The standard techniques of Huygens-type propagation integrals or plane-wave decompositions require quadruple oscillatory integrals that carry a significant computational cost. Two alternative, computationally efficient methods for such modeling are presented here. One uses a discrete nonparaxial basis expansion of the field, while the other uses Wigner functions for nonparaxial fields. Two possible nonparaxial generalizations of Gaussian Schell-model beams are presented and used to demonstrate the utility of the methods by computing the spatial distribution of several recently proposed definitions of the degree of polarization of a nonparaxial field.