US Patent 11467406 Field of view expanding system

This document relates to an optical device using waveguide that can enable propagation of large field of view images by use of metasurfaces, without the necessity of increasing the reflective index associated with the waveguide. An optical assembly can generate a compressed image corresponding to a wide field of view in order to ensure that the image can propagate through the waveguide according to TIR limits of the waveguide. The compressed image can be provided to a standard grating in-coupler, and can then be expanded by a metasurface out-coupler of the optical device to reproduce the wide field of view.