High Slant Angle Gratings for Eye Glow Suppression in Waveguide Based Displays

Abstract

Disclosed herein is various waveguide-based displays. One particular waveguide-based display includes a bottom substrate supporting a slanted grating. The bottom substrate is configured to maintain light in total internal reflection (TIR). The bottom substrate has an eye box side through which light is extracted out of the substrate towards an eyebox and an eye glow side through which eyeglow is extracted out of the substrate towards the outside world. The slanted grating includes repeating diffracting features each having a slant angle which is the angle formed between a face of the diffracting features and a normal to the bottom substrate. The slant angle is above or equal to 40 degrees. Advantageously, the slanted grating is configured to diffracted or reflect the TIR light out of the eye box side with minimal light is diffracted or reflected out of the eyebox side.

Dependencies are inferred from the claim text.