Focused Fields

This chapter derives the full vector equations for the fields in the vicinity of the focal point of a stigmatic lens following the technique of Richards and Wolf. The results are applied for linear, elliptical, radial, and azimuthal incident polarizations for both electric and magnetic fields. Power flow from the Poynting vector is calculated. The fields in a tilted image plane and tilted incident plane are given. Comparisons are made to the scalar Airy spot and Gaussian spot approximations. The overlap integral is used to estimate the coupling efficiency of a focused spot to a strip waveguide.