A piezoelectric driving device includes a vibrating plate, a first electrode, a piezoelectric layer, a second electrode layer provided above the vibrating plate. An active section is formed in a portion where the first electrode layer, the piezoelectric layer, and the second electrode layer overlap one another. The active section has a longitudinal direction and a latitudinal direction in plan view. At both ends in the latitudinal direction, ends of the first electrode layer are disposed in the same positions as ends of the wiring layer or further on the outer side than the ends, ends of the second electrode layer are disposed in the same positions as the ends of the wiring layer or further on the inner side than the ends, and the ends of the first electrode layer are disposed further on the outer side than the ends of the second electrode layer.

A piezoelectric vibration module has a first soft circuit board and a plurality of piezoelectric units. The first soft circuit board includes a plurality of cutting areas. Two adjacent cutting areas are spaced with a cut through groove. Each piezoelectric unit is respectively configured below each cutting area.

The present invention relates to an actuator including: a first ionic polymer layer disposed on underside of a first electrode layer; a second ionic polymer layer disposed on top of a second electrode layer; and a porous conducting interlayer disposed between the first ionic polymer layer and the second ionic polymer layer.

An actuator with a rectangular shape] is made of polarized electromechanical material having two large main surfaces and at least four side surfaces, two of which being longer than the other two side surfaces. At least one friction element is arranged on at least one of the shorter side surfaces. At least two active electrodes are arranged on one of the main surfaces, with one common electrode arranged on the other of the main surfaces The electromechanical material of the actuator is excitable to perform standing wave deformations due to an electric field generated therein for moving the friction element to drive an element. The actuator aspect ratio for its length to its thickness is between 3.9 and 4.1 and an aspect ratio for the length relative to width is between 2 and 5.

A vibration actuator that is capable of reducing difference of vibration velocities when a contact member is driven using a plurality of vibrators includes a vibrator device and the contact member, which moves relative to the vibrator device. The vibrator device includes the plurality of vibrators, which are connected in series, and a plurality of inductors, which are connected in parallel to the respective vibrators.

A form birefringent optical element includes a structured layer and a dielectric environment disposed over the structured layer. At least one of the structured layer and the dielectric environment includes a nanovoided polymer, the nanovoided polymer having a first refractive index in an unactuated state and a second refractive index different than the first refractive index in an actuated state. Actuation of the nanovoided polymer can be used to reversibly control the form birefringence of the optical element. Various other apparatuses, systems, materials, and methods are also disclosed.

A piezoelectric device that includes a film that has a first main surface and a second main surface, and has piezoelectricity; a first substrate; and a first connection member that connects the film to the first substrate. The first connection member is a thermosetting resin, and a curing temperature of the first connection member is lower than a temperature at which the film thermally contracts.

A piezoelectric vibrator has a first frequency region where the phase difference between a pickup signal representing the vibration of the piezoelectric vibrator and a drive signal that drives the piezoelectric vibrator does not monotonously change in accordance with the frequency of the drive signal and a second frequency region where the phase difference monotonously changes in accordance with the frequency of the drive signal. A method for controlling a piezoelectric driving apparatus including the piezoelectric vibrator controls the frequency of the drive signal in such a way that pickup voltage representing the amplitude of the pickup signal is fixed in the first frequency region and controls the frequency of the drive signal in such a way the pickup voltage is fixed with the phase difference maintained smaller than or equal to a prespecified value in the second frequency region.

A liquid discharge head includes: a nozzle plate including a nozzle; a liquid chamber substrate having an individual chamber; a diaphragm; a piezoelectric actuator including a piezoelectric body, a wiring portion covering a first region of the piezoelectric actuator; and a protective film covering a second region of the piezoelectric actuator other than the first region. A first outer periphery of the piezoelectric body in the second region is interior of a second outer periphery of the individual chamber in the second region. A gap region between the first outer periphery and the second outer periphery has: a first gap region having a first width in the longitudinal direction; and a second gap region having a second width in a transverse direction orthogonal to the longitudinal direction, the second width larger than the first width. The protective film covers a part of the first gap region in the second region.

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.