Physical optics is a branch of optics that studies optical phenomena, such as polarization, interference, diffraction, dispersion, scattering, etc. All these phenomena cannot be explained by using the approximations of geometric optics. In physical optics, the wave property of light is considered. Light waves are electromagnetic waves. The interaction of light with materials involves the modeling of both electric and magnetic fields of the light wave. When the propagation of light in systems cannot be solved analytically, numerical modeling techniques are used. These include the boundary element method, finite element method and the transmission-line matrix method. This book is a valuable compilation of topics, ranging from the basic to the most complex theories and principles in the field of physical optics. It aims to shed light on some of the unexplored aspects of this field. It aims to serve as a resource guide for students and experts alike and contribute to the growth of the discipline.