Generalized Huygens–Fresnel Principle

In classical electrodynamics, the famous Huygens– Fresnel principle is usually expressed in terms of some convolution integral formulations (CIFs). The conventional CIFs are generalized in this paper. The generalized CIFs are applicable to the simply connected dielectric scatterer, multiply connected dielectric scatterer, multi-body dielectric scattering system, and conductor-dielectric composite scattering system. In the various scatterers and scattering systems, the dielectric part can be either homogeneous isotropic or inhomogeneous anisotropic. For the various scatterers and scattering systems, the generalized CIFs can formulate the external scattered field, internal scattered field, internal incident field, and internal total field of the scatterers and scattering systems.