US Patent 11754838 Near-eye optical system

A near-eye optical system is configured to receive an image beam. The near-eye optical system includes a first optical waveguide, configured to expand the image beam in a first direction, and including a first surface, a second surface, a plurality of first reflecting slopes, and a plurality of second reflecting slopes. The first surface includes a first light-entering area. The second surface is opposite to the first surface. The second surface includes a concave area aligned with the first light-entering area, the concave area including a flat bottom surface, and a first inclined sidewall and a second inclined sidewall opposite to each other. The first reflecting slopes are disposed on the second surface, and the second reflecting slopes are disposed on the second surface.