Abstract: A lightguide for conveying image light to an eyebox of a display device includes a tunable grating, e.g. an out-coupling grating for out-coupling the image light from the lightguide. The tunable grating may be tuned or switched to effectively diffract light of a color channel of a color-sequential display. In augmented reality display systems, a lightguide combiner element may include a switchable grating to out-couple the image light only during short time intervals and to not out-couple the image light in between these time intervals. Effectively, the out-coupling grating is present only a portion of overall operation time of the display, which improves the transparency of the combiner element to the outside light and reduces rainbow effects.

Abstract: A display apparatus includes a lightguide for conveying images to a viewing area in a target field-of-view (FOV), and an eye detector for detecting a position of an eye in the viewing area. The lightguide includes a tunable segmented output diffraction grating, each segment for diffracting a portion of the image light to a corresponding segment of the viewing area. A controller is configured to switch to a non-diffracting state those of the segments that are located outside of the target FOV when viewed from the detected eye position.

Abstract: A fluidic optical element includes a fluid bilayer having a first fluid layer and a second fluid layer defining a fluid interface therebetween, and an electrode disposed over a surface of the fluid bilayer. The geometry of the fluid interface and hence the optical response of the fluid bilayer to incident light may be manipulated using the principle of dielectrophoresis.

Abstract: A display apparatus includes a lightguide for conveying images to a user in a target field-of-view (FOV). The lightguide includes a tunable output diffraction grating for displaying different portions of the target field-of-view at different time instances. The tunable output diffraction grating may include grating segments that are selectively switchable between a diffracting state and a non-diffracting state in dependence on a content of an image being displayed, providing content-dependent FOV switching.

Abstract: An actuator assembly includes (i) a first actuator stack having a first primary electrode, a first secondary electrode overlapping at least a portion of the first primary electrode, and a first electroactive layer disposed between and abutting the first primary electrode and the first secondary electrode, (ii) a second actuator stack having a second primary electrode, a second secondary electrode overlapping at least a portion of the second primary electrode, and a second electroactive layer disposed between and abutting the second primary electrode and the second secondary electrode; and (iii) a bonding layer disposed between the first actuator stack and the second actuator stack.

Abstract: A vibration control element includes a nanovoided polymer layer having a first damping coefficient and a first resonance frequency in a first state and a second damping coefficient and a second resonance frequency in a second state, where the first damping coefficient is different from the second damping coefficient and the first resonance frequency is different from the second resonance frequency.

Abstract: An actuator includes a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, a nanovoided polymer layer disposed between and abutting the primary electrode and the secondary electrode, the nanovoided polymer layer having a plurality of nanovoids dispersed throughout a polymer matrix, and a sealing layer at least partially encapsulating the nanovoided polymer layer, where the nanovoids include a fill gas.

Abstract: An optical transformer includes a light source and an array of photovoltaic cells optically coupled to the light source, where at least a portion of the photovoltaic cells are connected in series. An optical connector such as a waveguide or an optical fiber may be disposed between an output of the light source and an input of the array of photovoltaic cells. Configured to generate a high voltage output, the optical transformer may be configured to power a device such as an actuator that provides a tunable displacement as a function of voltage.

Abstract: An actuator includes a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, a nanovoided polymer layer disposed between and abutting the primary electrode and the secondary electrode, the nanovoided polymer layer having a plurality of nanovoids dispersed throughout a polymer matrix, and a sealing layer at least partially encapsulating the nanovoided polymer layer, where the nanovoids include a fill gas.

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: Disclosed devices may include a membrane, a first electrode supported by the membrane, a second electrode, a capacitance sensor configured to determine a capacitance measurement between the first electrode and the second electrode, and a controller configured to control an electrical potential applied between the electrode and the second electrode. The controller may be configured to modify the electrical potential based on the capacitance measurement. Example devices may include one or more flexible membranes that may, at least in part, define an enclosure that is at least partially filled with a dielectric fluid. Examples also include associated methods and systems.

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: 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.

Abstract: 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.

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: Disclosed devices may include a membrane, a first electrode supported by the membrane, a second electrode, a capacitance sensor configured to determine a capacitance measurement between the first electrode and the second electrode, and a controller configured to control an electrical potential applied between the electrode and the second electrode. The controller may be configured to modify the electrical potential based on the capacitance measurement. Example devices may include one or more flexible membranes that may, at least in part, define an enclosure that is at least partially filled with a dielectric fluid. Examples also include associated methods and systems.

Abstract: An example device includes a nanovoided polymer element, a first electrode, and a second electrode. The nanovoided polymer element may be located at least in part between the first electrode and the second electrode. In some examples, the nanovoided polymer element may include anisotropic voids. In some examples, anisotropic voids may be elongated along one or more directions. In some examples, the anisotropic voids are configured so that a polymer wall thickness between neighboring voids is generally uniform. Example devices may include a spatially addressable electroactive device, such as an actuator or a sensor, and/or may include an optical element. A nanovoided polymer layer may include one or more polymer components, such as an electroactive polymer.

Abstract: A high voltage-driven system includes a high voltage optical transformer and a high voltage driven device, where the high voltage optical transformer is located in close proximity to the high voltage driven device. A high voltage connection between the high voltage optical transformer and the high voltage driven device may be shorter than a low voltage connection between the high voltage optical transformer and a low voltage power source used to control the transformer.

Abstract: Embodiments of the present disclosure are generally directed to apparatuses, systems, and methods that utilize electroactive devices in connection with haptic devices (e.g., haptic touch sensors or haptic feedback elements). In some examples, a haptic feedback system may include an array of electroactive devices, each electroactive device including 1) a first electrode, 2) a second electrode, and 3) an electroactive polymer element disposed between the first electrode and the second electrode. The electroactive polymer element may include a nanovoided polymer material that is mechanically deformable in response to an electric field generated by a potential difference between the first electrode and the second electrode. The system may also include control circuitry electronically coupled to the array and configured to apply a voltage to at least one of the first electrode or the second electrode. Various other apparatuses, systems, and methods are also disclosed.

Abstract: An acoustic element includes a nanovoided polymer layer having a first nanovoid topology in an unactuated state and a second nanovoid topology different than the first nanovoid topology in an actuated state. Capacitive actuation of the nanovoided polymer layer, for instance, can be used to reversibly control the size and shape of the nanovoids within the polymer layer and hence tune its sound damping characteristics or sound transduction behavior, e.g., during operation of the acoustic element. An acoustic element may be configured for passive or active sound attenuation. Various other apparatuses, systems, materials, and methods are also disclosed.