  We propose a new method for integrating metasurfaces in optical design using
semi-analytical modelling of dielectric nanostructures. The latter computes the
output phase of an electric field incident on the metasurface, allowing their
use with ray-tracing software. This tool provides a method to use metasurfaces
in optical systems while using built-in optimization processes to avoid
time-consuming computation. To demonstrate the applicability and versatility of
our method, we present variations of a triplet composed of refractive elements
and a metasurface. For each of the systems, similar optical performances are
achieved. Our unique and innovative approach to joining metasurfaces and ray
tracing has the potential to promote the design of innovative systems by
exploiting the richness of metasurfaces and the functionality of conventional
lens design software.
