Hybrid meta/refractive lens design with inverse design using physical optics

Metasurface optics and refractive optics are combined to form hybrid lenses, where the refractive elements provide the optical power but metasurfaces are used to correct optical aberrations. We introduce an algorithm to optimize metasurface nanostructures in a hybrid lens with the freedom to arbitrarily interleave metasurface optics with refractive optics in the optical train. A scalar field, ray-wave hybrid propagation method is developed to propagate incident and derived adjoint fields through optical elements, enabling efficient metasurface nanostructure optimization under the framework of adjoint gradient optimization. Several numerical examples of lens configurations are provided to show the versatility of the algorithm.