Regularization fo 3D dyadic Green's function for flat interfaces

In this report we combine a known regularization method of the 3D dyadic Green’s function, with a known method to solving the Green’s function in cylindrical coordinates. We considered both the free space Green’s function, as well as at the scattering part in two different geometries. These geometries are a semi-infinite absorbing dielectric medium with a planar interface and a absorbing dielectric thin film. No regularization has has been done for these parts, as it was not needed in the situations considered in this study. Most problems in the study have been solved analytically. However, some integrals will have to be solved by numerical means, which will be done in a continuation of this study.