A quartz crystal resonator unit including a quartz crystal resonator having a quartz crystal blank, a frame surrounding an outer periphery of the quartz crystal blank, and coupling members connecting the frame to the quartz crystal blank. Moreover, a lid member and a base member are attached to the frame and seal the resonator. One or more outer electrodes is formed over end surfaces of the frame, the lid member, and the base member on a side where the coupling members are coupled. The one or more outer electrodes has a machinery quality factor smaller than that of the frame.

A piezoelectric element driving circuit includes a boosting circuit, a driving circuit, a waveform shaping circuit, and a computing circuit. The driving circuit includes a differential amplifier circuit with an LPF, an amplifier circuit with a BPF, an inverter, a resistor, and a comparator. The driving circuit applies a driving signal to a piezoelectric element of a piezoelectric pump. The waveform shaping circuit extracts a voltage signal from the driving circuit. On the basis of the voltage signal, the waveform shaping circuit and the computing circuit determine a voltage value corresponding to driving current flowing through the piezoelectric element. The computing circuit outputs a control signal to the boosting circuit on the basis of the voltage value. The boosting circuit sets the value of a DC supply voltage on the basis of the control signal, and outputs the DC supply voltage.

Apparatus and method that includes providing a variable-parameter electrical component in a high-field environment and based on an electrical signal, automatically moving a movable portion of the electrical component in relation to another portion of the electrical component to vary at least one of its parameters. In some embodiments, the moving uses a mechanical movement device (e.g., a linear positioner, rotary motor, or pump). In some embodiments of the method, the electrical component has a variable inductance, capacitance, and/or resistance. Some embodiments include using a computer that controls the moving of the movable portion of the electrical component in order to vary an electrical parameter of the electrical component. Some embodiments include using a feedback signal to provide feedback control in order to adjust and/or maintain the electrical parameter. Some embodiments include a non-magnetic positioner connected to an electrical component configured to have its RLC parameters varied by the positioner.

A piezoelectric actuator includes a piezoelectric element that includes a piezoelectric unit including a ferroelectric, which has an asymmetric bipolar P-E curve, a capacitor connected to the piezoelectric unit in series, and a resistor connected to the capacitor in series and connected to the ferroelectric in parallel; and a drive unit that inputs a drive waveform Vd, which includes a DC offset component of which polarity is opposite to polarization of the ferroelectric, to the piezoelectric element to drive the piezoelectric element. A value of a coercive electric field Ec.sub.1, a value of a coercive electric field Ec.sub.2, the capacitance C.sub.s of the capacitor, the capacitance C.sub.pz of the ferroelectric, combined resistance R.sub.p of the resistance of the resistor and the resistance of the ferroelectric, and a fundamental angular frequency ω of the drive waveform satisfy Expressions I to III, wherein

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The invention is directed to a device and to a method for generating an oscillatory motion of a mass, wherein an oscillating electrical signal and/or an operation power is wirelessly transmitted in order to facilitate retrofitting the device.

Provided is a piezoelectric thin film device in which lattice mismatch between a piezoelectric thin film and a lower electrode layer (first electrode layer) is reduced. A piezoelectric thin film device 10 comprises a first electrode layer 6a and a piezoelectric thin film 2 laminated directly on the first electrode layer 6a; the first electrode layer 6a includes an alloy composed of two or more metal elements; the first electrode layer 6a has a face-centered cubic lattice structure; and the piezoelectric thin film 2 has a wurtzite structure.

A driver for a circuit with a capacitive load, includes a power converter configured to receive a DC input voltage from an input stage, generate a switching voltage at a switching node, and output an output voltage forming an analog waveform at an output stage. The power converter includes a first switch connected between an inductive device and a ground, a second switch connected between the inductive device and the output stage, and a controller to control the first switch and the second switch. The analog waveform has an amplitude at least two times greater than the input voltage.

Provided is an ultrasonic probe that is capable of easily dissipating heat generated therein using porous carbon allotrope foams. The ultrasonic probe includes: a matching layer; a piezoelectric layer disposed on a bottom surface of the matching layer; and a backing layer disposed on a bottom surface of the piezoelectric layer and formed of porous carbon allotrope foams and backing materials.

There is provided a vibration generating device including: a housing having an internal space; a vibration member having one end fixedly attached to the housing; a piezoelectric element installed on the vibration member; and a mass body fixedly attached to the vibration member, wherein the vibration member includes an installation part on which the piezoelectric element is installed, and an extension part extended from at least one side surface of the installation part, and a maximum displacement portion of the vibration member is changed depending on a vibration mode.

An elastic wave device includes a supporting substrate, a high-acoustic-velocity film stacked on the supporting substrate and in which an acoustic velocity of a bulk wave propagating therein is higher than an acoustic velocity of an elastic wave propagating in a piezoelectric film, a low-acoustic-velocity film stacked on the high-acoustic-velocity film and in which an acoustic velocity of a bulk wave propagating therein is lower than an acoustic velocity of a bulk wave propagating in the piezoelectric film, the piezoelectric film is stacked on the low-acoustic-velocity film, and an IDT electrode stacked on a surface of the piezoelectric film.