RIGOROUS JUSTIFICATION OF THE LOCALIZED APPROXIMATION TO THE BEAM-SHAPE COEFFICIENTS IN GENERALIZED LORENZ-MIE THEORY .2. OFF-AXIS BEAMS

Generalized Lorenz-Mie theory describes electromagnetic scattering of an arbitrary light beam by a spherical particle. The localized approxi mation is an analytical function that accurately models the beam-shape coefficients that give the decomposition of a focused Gaussian beam i nto partial waves. A mathematical justification and physical interpret ation of the localized approximation is presented for a focused off-ax is Gaussian beam that propagates parallel to but not along the z axis.