Diffraction Pattern Calculation from a Reflection-Type Diffractive Beam Splitter

Most diffractive beam splitter is designed with the normal incidence assumption. More specifically, the structure design from transmission function, which is achieved by using Iterative Fourier Transform Algorithm, is done by using the thin element approximation under normal incidence. However, in the practical situation, to avoid the block of reflection beam when using a reflection-type beam splitter, the splitter must be rotated. This use case demonstrates how the diffracted pattern changes when the beam splitter is tilted for different angles.