Metalens stack on waveguide combiners for AR/VR glasses
Embodiments of the present application generally relate to augmented reality and virtual reality glasses having stacked lenses. The augmented reality (AR) and virtual reality (VR) glasses includes a pair of lenses retained by a frame. A lens stack is utilized in the pair of lenses. The lens stack may include multiple metasurfaces that improve the focus adjustment for both the real and virtual images as well as a prescription lens or prescription metasurface in the lens stack. The metasurfaces are coupled to a waveguide combiner to assist in overlaying virtual images on ambient environments. By utilizing a lens stack, the total weight of the glasses will decrease.
1 . An optical device comprising:
a waveguide combiner, the waveguide combiner including:
one or more first gratings disposed on a first surface of a substrate; and
one or more second gratings disposed on a second surface of the substrate;
a convex lens coupled to the one or more first gratings with a first pair of spacers;
a concave lens coupled to the one or more second gratings with a second pair of spacers; and
a prescription lens coupled to the concave lens with a third pair of spacers.
2 . The optical device of claim 1 , wherein the one or more first gratings and the one or more second gratings include a plurality of optical device structures.
3 . The optical device of claim 2 , wherein the plurality of optical device structures are nanostructures having sub-micron dimensions.
4 . The optical device of claim 2 , wherein the plurality of optical device structures are binary or angled relative to the first surface of the substrate and the second surface of the substrate.
5 . The optical device of claim 4 , wherein the plurality of optical device structures comprise an angle of 15 degrees to 85 degrees.
6 . The optical device of claim 2 , wherein the optical device structures comprise silicon oxycarbide (SiOC), titanium dioxide (TiO 2 ), silicon dioxide (SiO 2 ), vanadium (IV) oxide (VOx), aluminum oxide (Al 2 O 3 ), aluminum-doped zinc oxide (AZO), indium tin oxide (ITO), tin dioxide (SnO 2 ), zinc oxide (ZnO), tantalum pentoxide (Ta 2 O 5 ), silicon nitride (Si 3 N 4 ), zirconium dioxide (ZrO 2 ), niobium oxide (Nb 2 O 5 ), cadmium stannate (Cd 2 SnO 4 ), silicon carbon-nitride (SiCN) containing materials, or combinations thereof.
7 . The optical device of claim 1 , wherein:
the one or more first gratings include a first image incoupler and a first image outcoupler; and
the one or more second gratings include a second image incoupler and a second image outcoupler.
8 . The optical device of claim 1 , wherein the first pair of spacers and the second pair of spacers include a polystyrene material or an adhesive material.
9 . The optical device of claim 1 , wherein the substrate comprises silicon (Si), silicon dioxide (SiO 2 ), fused silica, quartz, silicon carbide (SiC), germanium (Ge), silicon germanium (SiGe), indium phosphide (InP), gallium arsenide (GaAs), gallium nitride (GaN), or sapphire or combinations thereof.
10 . The optical device of claim 1 , wherein the convex lens is operable to focus a real image on a user's retina.
11 . The optical device of claim 1 , wherein the concave lens is operable to bring a virtual image nearer to a user's retina.
12 . The optical device of claim 11 , wherein the concave lens is operable to bring the virtual image about 0.2 m to about 3 m of the user's retina.
13 . An optical device comprising:
a waveguide combiner, the waveguide combiner comprising:
an image incoupler comprising a plurality of optical device structures and an image outcoupler comprising the plurality of optical device structures disposed over a first surface of a substrate; and
a convex lens coupled to the waveguide combiner with a first pair of spacers disposed over the first surface; and
a concave lens coupled to the waveguide combiner with a second pair of spacers disposed over a second surface of the substrate; and a prescription lens coupled to the concave lens with a third pair of spacers.
14 . The optical device of claim 13 , wherein the plurality of optical device structures comprise silicon oxycarbide (SiOC), titanium dioxide (TiO 2 ), silicon dioxide (SiO 2 ), vanadium (IV) oxide (VOx), aluminum oxide (Al 2 O 3 ), aluminum-doped zinc oxide (AZO), indium tin oxide (ITO), tin dioxide (SnO 2 ), zinc oxide (ZnO), tantalum pentoxide (Ta 2 O 5 ), silicon nitride (Si 3 N 4 ), zirconium dioxide (ZrO 2 ), niobium oxide (Nb 2 O 5 ), cadmium stannate (Cd 2 SnO 4 ), silicon carbon-nitride (SiCN) containing materials, or combinations thereof.
15 . The optical device of claim 13 , wherein the plurality of optical device structures are binary or angled relative to the first surface of the substrate and the second surface of the substrate.
16 . The optical device of claim 15 , wherein the plurality of optical device structures comprise an angle of 15 degrees to 85 degrees.
17 . An optical device comprising:
a waveguide combiner, the waveguide combiner including:
an image incoupler comprising a plurality of optical device structures and an image outcoupler comprising the plurality of optical device structures disposed over a first surface of a substrate; and
a convex lens coupled to the waveguide combiner with a first pair of spacers disposed over the first surface; and
a concave lens coupled to the waveguide combiner with a second pair of spacers disposed over a second surface of the substrate; and
a prescription lens coupled to the concave lens with a third pair of spacers.
18 . The optical device of claim 17 , wherein the substrate comprises silicon (Si), silicon dioxide (SiO 2 ), fused silica, quartz, silicon carbide (SiC), germanium (Ge), silicon germanium (SiGe), indium phosphide (InP), gallium arsenide (GaAs), gallium nitride (GaN), or sapphire or combinations thereof.
19 . The optical device of claim 17 , wherein the first pair of spacers and the second pair of spacers include a polystyrene material or an adhesive material.