Optical systems with flare-mitigating angular filters

Abstract

An electronic device may include a display with an optical combiner. The combiner may include a waveguide and a cross coupler on the waveguide. The combiner may redirect light from a display module to an eye box while passing world light to the eye box within a field of view. The cross coupler may include surface relief gratings or other broadband gratings. The combiner may include an angular filter that at least partially overlaps the cross coupler. The cross coupler may include surface relief grating structures or other broadband gratings. The angular filter may include angled absorbers or diffractive gratings. The angular filter may prevent world light that would otherwise produce distracting flares at the eye box (e.g., world light incident on the waveguide outside the field of view such as high-incident angle light from an overhead light source) from passing to the cross coupler.