Abstract: A lighting assembly may include a light source and a reflective polarizer overlapping the light source. A portion of light that is incident on the reflective polarizer may not pass through the reflective polarizer and may be reflected back to the light source. The light source may include at least one of a light emitting diode (LED), a micro-LED, an organic light emitting diode (OLED), a micro-OLED, a liquid crystal on silicon (LCoS), or an fLCoS light source. The reflective polarizer may include a polymer birefringent multilayer structure of alternating first layers and second layers. The first layers may each include an isotropic polymer thin film the second layers each include an anisotropic polymer thin film. Various other devices, systems, and methods are also disclosed.

Abstract: 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.

Abstract: A notched filter includes a multilayer having alternating first and second polymer layers, the first polymer layers each including an isotropic polymer thin film having in-plane refractive indices n1x and n1y, and the second polymer layers each including an isotropic or anisotropic polymer thin film having in-plane refractive indices n2x and n2y, where a thickness of each successive first polymer layer decreases with increasing distance from a centerline of the multilayer, and a thickness of each successive second polymer layer increases with increasing distance from the centerline. Such a filter may be configured to reflect incident light having a desired polarization state within a predetermined and relatively narrow band.

Abstract: An actuator assembly includes a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, and an electroactive polymer layer disposed between the primary electrode and the secondary electrode, where the electroactive polymer layer includes a non-vertical (e.g., sloped) sidewall with respect to a major surface of at least one of the electrodes. The electroactive polymer layer may be characterized by a non-axisymmetric shape with respect to an axis that is oriented orthogonal to an electrode major surface.

Abstract: A method of forming a uniaxially oriented crystalline polymer article includes heating a segment of a crystallizable polymer article to a first temperature, applying a stress to the crystallizable polymer article in an amount effective to induce a positive strain within the segment of the crystallizable polymer article, and heating the segment of the crystallizable polymer article to a second temperature greater than the first temperature while continuing to apply the stress.

Abstract: A thermoplastic interposer formed of ordered polymer sheets that may be configured to act as an interconnect and as a thermal energy spreader. In examples, the thermoplastic interposer may include one or more extensions or wings to further dissipate heat. In examples, laser direct structuring (LDS) may be used to form or more through silicon vias (TSVs) or through-chip vias. In examples, the ordered polymer sheets may be extruded via a roll-to-roll process, stacked, and processed to form a laminate interposer structure that makes up the interposer. In examples, the thermoplastic interposer may be used in multi-layer structures interconnecting two or more board assemblies such as printed circuit boards (PCB)s.

Abstract: An eye is illuminated with infrared illumination light. Illuminating the eye includes illuminating a near-eye ellipsoidal lensing structure. A tracking image of Purkinje reflections of the infrared illumination light is captured by a camera. An eye position of the eye is determined in response to the tracking image.

Abstract: 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.

Abstract: A liquid lens with flexible transparent active layers on both sides of a fluid is transformed along two distinct deformation axes. The flexible transparent active layers include piezoelectric materials that actuate the lens in response to applied voltage(s). The piezoelectric properties and actuation mechanism of the transparent layers are arranged to deform the lens cylindrically along different axes resulting in a net spherical deformation or a combination of spherical and cylindrical deformation with substantially less distortion than spherically deforming layers. The piezoelectric active layers may be polymer or ceramic with isotropic or anisotropic mechanical stiffness. Alternatively, a pair of transparent, internal layers are positioned between the front and rear surfaces. The active layers, front and/or rear, are dual layers affixed together with an adhesive or single layers.

Abstract: A mechanically and piezoelectrically anisotropic polymer article is formed from a crystallizable fluoropolymer and a nucleating agent. The polymer article may be a thin film or a fiber, for example. A crystalline phase may constitute at least approximately 50% of the polymer article. In certain examples, a fluoropolymer may include vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropylene, and vinyl fluoride. The polymer article may include up to approximately 10 wt. % of the nucleating agent. Such a polymer article is optically transparent, has an elastic modulus of at least approximately 3 GPa, and an electromechanical coupling factor (k31) of at least approximately 0.15.

Abstract: A display system may include a light source that emits input light having a wavelength within a source wavelength range and an array of color conversion units overlapping a display area. A first set of color conversion units of the array of color conversion units may include a first color conversion medium that converts the input light to a first color of light having a wavelength within a first wavelength range that is different than the source wavelength range. The display system may also include a waveguide having an out-coupler that directs the input light from the light source toward the array of color conversion units. Various other devices, systems, and methods are also disclosed.

Abstract: A multilayer polymer thin film includes an anti-reflective coating directly overlying a reflective polarizer stack. The reflective polarizer stack includes alternating first and second polymer layers, where the first layers include an isotropic polymer thin film and the second layers include an anisotropic polymer thin film. The anti-reflective coating (ARC) includes alternating third and fourth layers, where the third layers include an isotropic polymer thin film or an anisotropic polymer thin film and the fourth layers include an isotropic polymer thin film. The multilayer polymer thin film may be formed by co-extrusion where the reflective polarizer stack and the anti-reflective coating are formed simultaneously.

Abstract: An optical device includes a first polarization selective reflector; and a second polarization selective reflector positioned relative to the first polarization selective reflector so that the first polarization selective reflector directs first light having a first polarization toward the second polarization selective reflector and the second polarization selective reflector directs second light having a second polarization toward the first polarization selective reflector. A first plane defined by the first polarization selective reflector intersects a second plane defined by the second polarization selective reflector at a first angle.

Abstract: An example apparatus may include a display and an optical configuration configured to provide an image of a display, for example, in a head-mounted device. An example apparatus may include a display and an optical configuration including a first lens assembly and a second lens assembly. The first lens assembly may include a first lens, a first reflector, and an actuator. The second lens assembly may include a second lens and a second reflector. An example apparatus may include a controller configured to apply at least one electrical signal to the actuator to control the optical power of the first lens. The display light may pass through the actuator, which may be transparent and may include a plurality of actuator layers. Other devices, methods, systems and computer-readable media are also disclosed.

Abstract: The disclosed apparatus may include a first rigid lens; a second rigid lens, a seal that couples the first rigid lens and the second rigid lens together, where the first rigid lens, the second rigid lens, and the seal define a cavity; and a fluid within the cavity, where the seal is adapted to admit expansions of the fluid within the cavity. Various other apparatuses and methods also disclosed.

Abstract: An example apparatus may include a display and an optical configuration configured to provide an image of a display, for example, in a head-mounted device. An example apparatus may include a display, a first lens assembly including a lens and a reflector, and a second lens assembly including a second lens and a second reflector. In some examples, the first lens assembly has a front surface configured to receive display light from the display when the display is energized. The first lens assembly may include a Fresnel surface (e.g., a Fresnel surface including facets and steps) that may, for example, be formed in a lens surface, or in the surface of a substrate supported by a lens surface. Other devices, methods, systems and computer-readable media are also disclosed.

Abstract: An actuator may be integrated into an optical element such as a liquid lens and configured to create spherical curvature as well as a variable cylinder radius and axis in a surface of the optical element. An example actuator may include a stack of electromechanical layers, and electrodes configured to apply an electric field independently across each of the electromechanical layers. Within the stack, an orientation of neighboring electromechanical layers may differ, e.g., stepwise, by at least approximately 10°.

Abstract: A liquid lens architecture includes a transparent substrate, a multilayer thermoplastic polyurethane (TPU)-based membrane overlying at least a portion of the transparent substrate, and a liquid layer disposed between and abutting the transparent substrate and the multilayer thermoplastic polyurethane-based membrane. The TPU-based membrane may exhibit a reversible elastic response to imposed strains of up to approximately 2% and is configured to limit the transpiration of fluid to less than approximately 10?2 g/m2/day.

Abstract: A liquid lens includes a transparent substrate, a multilayer polyurethane-based membrane overlying the transparent substrate, and a liquid layer disposed between and abutting the transparent substrate and the multilayer polyurethane-based membrane. The multilayer polyurethane-based membrane, which may include thermoplastic and/or thermoset polymer layers, may be formed by slot die coating or gravure coating one or more constituent layers and may exhibit a reversible elastic response to imposed strains of up to approximately 5% while limiting the transpiration of fluid therethrough to less than approximately 10?2 g/m2/day.

Abstract: A display device includes a display panel including a first array of light emitters having a first spacing in a first emission region of the display panel and a second array of light emitters having a second spacing in a second emission region of the display panel. The second spacing is distinct from the first spacing. The display device includes an optical filter including a first filter region and a second filter region. The first filter region changes distribution of first light from the first array of light emitters impinging on the first filter region so that the first light has a first distribution after passing through the first filter region. The second filter region changes distribution of second light from the second array of light emitters impinging on the second filter region so that the second light has a second distribution after passing through the second filter region.