Patent Document ID: 20170102623
Application ID: 15285051
Patent Flag: 0

Claim One:
1. A method of simulating interaction of radiation with a structure, the method comprising the steps of: (a) defining a layered structure model to represent the structure in a two- or three-dimensional model space, the structure model defining for each layer of the structure a homogeneous background permittivity and for at least one layer a non-homogeneous contrast permittivity; and (b) using the layered structure model in a modal method to simulate interaction of radiation with the structure, a total field being calculated in terms of a background field and a contrast field, the background field within each layer being independent of the non-homogeneous contrast permittivity, wherein step (b) uses Maxwell's equation in a Born approximation, whereby a product of the non-homogeneous contrast permittivity and the total field is approximated by a product of the non-homogeneous contrast permittivity and the background field.