Hybrid model to simulate optical systems combining metasurfaces and classical refractive elements

This paper presents an accurate and fast numerical method to compute the imaging performance of a centimeter-scale optical system comprising at least one metasurface that can be used inside an optimization design loop to allow direct design of the full system. In order to fit in the optimization design process, the optical response of the metasurfaces is approximated with a surrogate model of the locally periodic response of their constitutive meta-atoms described by a relevant set of variables. This surrogate model is used to obtain the performance of imaging systems containing both metasurfaces and refractive lenses using either the generalized Snell's law or a more physically accurate hybrid ray optics/wave optics model that accounts for the diffraction occurring at metasurfaces. We show that the hybrid model is necessary to obtain an accurate prediction of the modulus transfer function of systems containing metasurfaces with non-negligible optical power.