A first optical waveguide, a second optical waveguide, a connection optical waveguide including a resin core that optically connects the first optical waveguide and the second optical waveguide are included. The resin core is covered with cladding. The second optical waveguide has a core with a diameter that is different from a diameter of a core of the first optical waveguide. The resin core is disposed between an end surface of the first optical waveguide and an end surface of the second optical waveguide and optically connects the first optical waveguide and the second optical waveguide. Moreover, the resin core is configured with a cured photo-curable resin.

A graded-index optical element may include a nanovoided material including a first surface and a second surface opposite the first surface. The nanovoided material may be transparent between the first surface and the second surface. Additionally, the nanovoided material may have a predefined change in effective refractive index in at least one axis due to a change in at least one of nanovoid size or nanovoid distribution along the at least one axis. Various other elements, devices, systems, materials, and methods are also disclosed.

A nanovoided polymer-based material may include a bulk polymer material defining a plurality of nanovoids and an interfacial film disposed at an interface between each of the plurality of nanovoids and the bulk polymer material. The interfacial film may include one or more layers of material. A method of forming a nanovoided polymer-based material may include (1) forming a bulk polymer material defining a plurality of nanovoids and (2) forming an interfacial film at an interface between each of the plurality of nanovoids and the bulk polymer material. Various other methods, systems, and materials are also disclosed.

An optical waveguide is provided and includes: a core forming layer with a high refractive index; and a first clad layer with a low refractive index, bonded to a first main surface of the core forming layer. The core forming layer is provided in its plane direction with a core portion, lateral clad portions each having one side adjacent to a corresponding side of the core portion, and high refractive index portions each adjacent to the other side of a corresponding one of the lateral clad portions. The core portion is provided in its plane direction with a central region, and GI regions in each of which a refractive index continuously decreases from the central region toward an interface with the corresponding one of the lateral clad portions. The lateral clad portions each include a region having a constant refractive index.

A method for establishing optical coupling between spatially separated first and second planar waveguides includes arranging an optical interconnect on the first planar waveguide. The optical interconnect has first and second end portions and an intermediate portion. Each of the end portions has an inverse taper. The second planar waveguide is arranged on the optical interconnect so that the second planar waveguide overlaps with one of the inverse tapered end portions but not the other inverse tapered end portion to thereby enable an adiabatic transition of an optical signal from the first planar waveguide to the second planar waveguide via the optical interconnect. The first and second planar waveguides have different refractive indices at an operating wavelength and the optical interconnect have a higher refractive index at the operating wavelength than the refractive indices of a core of the first planar waveguide and a core of the second planar waveguide.

According to the present invention, an optical waveguide includes a core layer having a first surface and a second surface having a front and back relationship with each other, the core layer including a core portion extending along a core axis and a side clad portion, a first cover layer provided on the first surface, the first cover layer having an adhesive surface on an opposite side of the core layer, and a second cover layer provided on the second surface, the second cover layer having an opposite surface on an opposite side of the core layer. The optical waveguide has a sheet shape and has a first recess portion that is open to the adhesive surface. When the adhesive surface is viewed in plan view, the first recess portion includes a first groove extending along a first axis that intersects with the core axis. The optical waveguide is used by being adhered to an adhesion target via an adhesive layer in contact with the adhesive surface.

In some examples, a method includes forming a material layer on a substrate, partially polymerizing a component of the material layer, to form fluid-filled droplets within a partially polymerized matrix, deforming the material layer to form anisotropic fluid-filled droplets, and further polymerizing the partially polymerized matrix to form an anisotropic voided polymer, including anisotropic voids in a polymer matrix. The anisotropic voids may include anisotropic nanovoids. Example methods may further include depositing electrodes on the anisotropic voided polymer so that at least a portion of the anisotropic voided polymer is located between the electrodes. Examples may include forming electroactive elements including an anisotropic nanovoided polymer, and devices (such as sensors and/or actuators) including electroactive elements.

In some examples, a device includes a multilayer structure, a first electrode, and a second electrode, where the multilayer structure is located at least in part between the first electrode and the second electrode, and the multilayer structure includes a nanovoided polymer layer, and a solid layer. The solid layer may include a non-nanovoided layer. The nanovoided polymer layer may be an electroactive layer. The device may further include a control circuit configured to apply an electrical potential between the first electrode and the second electrode, which may induce a mechanical deformation of the multilayer.

A method, system, and computer program product for using photorefractive material for analog optic storage and other applications of optical neuromorphic systems. The method may include coupling electromagnetic radiation into a first optical input and a second optical input, where the first optical input and the second optical input are part of an integrated optical device, the integrated optical device including: a first optical mode coupler connected to a first pair of optical ports including a first optical input and output; a second optical mode coupler connected to a second pair of optical ports including a second optical input and output, and the first optical mode coupler connected to the second optical mode coupler using a pair of arms (including a photorefractive material). The method may also include obtaining an optical interference pattern in the photorefractive material of each arm of the integrated optical device.

An augmented reality device includes a projector, projector optics optically coupled to the projector, and an eyepiece optically coupled to the projector optics. The eyepiece includes an eyepiece waveguide characterized by lateral dimensions and an optical path length difference as a function of one or more of the lateral dimensions.