A piezoelectric device includes a piezoelectric body, a vibration plate that vibrates when the piezoelectric body is driven, a first electrode positioned between the piezoelectric body and the vibration plate, and a second electrode positioned to be separated from the first electrode by the piezoelectric body. The piezoelectric body has an active portion that is a part sandwiched between the first electrode and the second electrode in a first direction along a thickness direction of the piezoelectric body, and a change width of a dC/dV value, which represents a change in capacitance with respect to a change in a voltage applied along a second direction orthogonal to the first direction, from one end of the active portion on a side of the first electrode to the other end of the active portion on a side of the second electrode in the first direction is 10% or less.

A piezoelectric device comprising a transparent substrate; a transparent barrier layer on the substrate; a transparent piezoelectric layer on the transparent barrier layer; a transparent layer of interdigitated electrodes on the transparent piezoelectric layer; wherein the piezoelectric device further comprises a transparent dielectric layer at least on the portion of piezoelectric layer that is between successive fingers of the transparent layer of interdigitated electrodes, the transparent dielectric layer having a refractive index lower than a refractive index of the transparent layer of interdigitated electrodes and a dielectric strength superior to 3 MV/m.

The disclosed embodiments are generally directed to optical systems. The optical systems may include a proximal lens that may transmit light toward an eye of a user. The optical systems may also include a distal lens that may, in combination with the proximal lens, correct for at least a portion of a refractive error of the eye of the user. The optical systems may further include a selective transmission interface. The selective transmission interface may couple the proximal lens to the distal lens, transmits light having a selected property, and does not transmit light that does not have the selected property. The optical system can also include an accommodative lens, such as a liquid lens. Various other methods, systems, and computer-readable media are also disclosed.

An electroactive device may include (1) an electroactive polymer element having a first surface and a second surface opposite the first surface, the electroactive polymer element comprising a nanovoided polymer material, (2) a primary electrode abutting the first surface of the electroactive polymer element, and (3) a secondary electrode abutting the second surface of the electroactive polymer element. The electroactive polymer element may be deformable from an initial state to a deformed state by application of an electrostatic field produced by a potential difference between the primary electrode and the secondary electrode. Various other devices, systems, and methods are also disclosed.

An RF integrated circuit device can includes a substrate and a High Electron Mobility Transistor (HEMT) device on the substrate including a ScAlN layer configured to provide a buffer layer of the HEMT device to confine formation of a 2DEG channel region of the HEMT device. An RF piezoelectric resonator device can be on the substrate including the ScAlN layer sandwiched between a top electrode and a bottom electrode of the RF piezoelectric resonator device to provide a piezoelectric resonator for the RF piezoelectric resonator device.

An RF integrated circuit device can includes a substrate and a High Electron Mobility Transistor (HEMT) device on the substrate including a ScAlN layer configured to provide a buffer layer of the HEMT device to confine formation of a 2DEG channel region of the HEMT device. An RF piezoelectric resonator device can be on the substrate including the ScAlN layer sandwiched between a top electrode and a bottom electrode of the RF piezoelectric resonator device to provide a piezoelectric resonator for the RF piezoelectric resonator device.

A system for a wireless communication infrastructure using single crystal devices. The wireless system can include a controller coupled to a power source, a signal processing module, and a plurality of transceiver modules. Each of the transceiver modules includes a transmit module configured on a transmit path and a receive module configured on a receive path. The transmit modules each include at least a transmit filter having one or more filter devices, while the receive modules each include at least a receive filter. Each of these filter devices includes a single crystal acoustic resonator device formed with a thin film transfer process with at least a first electrode material, a single crystal material, and a second electrode material. Wireless infrastructures using the present single crystal technology perform better in high power density applications, enable higher out of band rejection (OOBR), and achieve higher linearity as well.

A system for a wireless communication infrastructure using single crystal devices. The wireless system can include a controller coupled to a power source, a signal processing module, and a plurality of transceiver modules. Each of the transceiver modules includes a transmit module configured on a transmit path and a receive module configured on a receive path. The transmit modules each include at least a transmit filter having one or more filter devices, while the receive modules each include at least a receive filter. Each of these filter devices includes a single crystal acoustic resonator device formed with a thin film transfer process with at least a first electrode material, a single crystal material, and a second electrode material. Wireless infrastructures using the present single crystal technology perform better in high power density applications, enable higher out of band rejection (OOBR), and achieve higher linearity as well.

An object of the present invention is to improve the piezoelectricity of a PVT having the VDF ratio of 82 to 90% represented by a copolymer, in which copolymerization of vinylidene fluoride VDF and trifluoroethylene TrFe is 85 versus 15 (this is written as PVT85/15, and which is excellent in resistance to deformation, and heat resistance, etc. And therefore, it is also to obtain a piezoelectric film having piezoelectricity exceeding a PVT of less than 82 mol % of VDF represented by a PVT75/25, which conventionally shows the highest piezoelectricity, and a method of producing the same. A piezoelectric film is made of a mixture of two kinds (for example, a first copolymer is PVT85/15 and a second copolymer is PVT75/25) having different polymerization ratios of vinylidene fluoride VDF and trifluoroethylene TrFE.

A sensing film includes a base layer, a piezoelectric layer formed on the base layer, and a first electrode and a second electrode formed on the piezoelectric layer. The first and second electrodes are spaced apart and electrically insulated from each other. The first electrode includes a first connecting portion and a number of first extending portions coupled to the first connecting portion. The second electrode includes a second connecting portion and a number of second extending portions coupled to the second connecting portion. The first connecting portion and the second connecting portion are spaced apart and face each other. The first extending portions extend from a side of the first connecting portion toward the second connecting portion. The second extending portions extend from a side of the second connecting portion toward the first connecting portion. The first extending portions and the second extending portions are alternately arranged.