Analysis of Metasurface Transmission Coefficients based on Electromagnetic Field Theory

The existing theoretical analysis methods related to the design of transmissive metasurface units are often limited to specific structures, rarely involving the oblique incidence case, and are not highly interpretable. In this paper, based on the fundamental electromagnetic field theory, the transmission coefficient equations for transverse electric and transverse magnetic waves in a single-layer medium are derived, which can be applied to arbitrary incidence angles. Based on proposed formulas and the equivalent medium theory, we discuss how thickness effect the transmission performance of metasurfaces, which theoretically illustrates the feasibility of the design of multifunctional transmission metasurfaces and give a reference for the design of metasurfaces.