Abstract: Disclosed herein are techniques for waveguide displays. According to some embodiments, a method for fabricating a multi-layer optical device comprising includes measuring thickness variations within a target area of a first substrate for fabricating a first optical element of the multi-layer optical device and determining, based on the measuring, a thickness correction map indicating amounts of material to be removed in different regions of the target area to planarize the target area. The method also includes planarizing the target area of the first substrate based on the thickness correction map and bonding the first substrate to a second substrate that comprises a second optical element fabricated thereon to form a layer stack, wherein the target area of the first substrate aligns with and is bonded to the second optical element to form a multi-layer structure. The method further includes singulating the multi-layer structure from the layer stack.

Abstract: A waveguide display includes a waveguide configured to transport display light visible to human eyes, a coupler formed on a broadside surface of the waveguide and configured to couple portions of the display light out of the waveguide at one or more regions of the waveguide, and a photovoltaic device at an edge of the waveguide, the photovoltaic device configured to convert at least a portion of the display light that reaches the edge of the waveguide into electrical power.

Abstract: The disclosed method for recovering optical properties of transparent substrates may include performing a post-etching annealing process on a transparent substrate. The method may also include applying a plasma treatment to the transparent substrate, performing an atomic layer etching treatment on the transparent substrate, and/or performing a cleaning process. Various other methods, devices, and systems are also disclosed.

Abstract: A method of fabricating a surface-relief structure in a material layer (e.g., including dielectric or semiconductor material) includes forming a mask layer on the material layer, implanting ions (e.g., using ion beam implantation or ion beam etching) into a plurality of regions of the material layer using the mask layer and an ion beam having a slant angle equal to or greater than 0° (e.g., greater than about 30° or about 45°) with respect to a surface normal direction of the material layer to increase the oxidation rate (or reduction rate) of the plurality of regions of the material layer, selectively oxidizing (or reducing) the plurality of regions of the material layer that include implanted ions, and selectively etching the oxidized or reduced materials in the plurality of regions of the material layer to form the surface-relief structure in the material layer.