An apparatus and a method for generating a non-thermal atmospheric pressure plasma are disclosed. In an embodiment, an apparatus for generating a non-thermal atmospheric-pressure plasma includes a first piezoelectric transformer, a second piezoelectric transformer, and a drive circuit configured to apply an input voltage to each of the piezoelectric transformers, and wherein the input voltage applied to the first transformer is phase-shifted by 90° in relation to the input voltage applied to the second transformer.

A piezoelectric vibration device is provided that includes a piezoelectric transformer, a flexible board and a case. The flexible board includes an element-mounting terminal connected to an outer electrode of the piezoelectric transformer, and an external connection terminal connected to a wiring board. The case has a securing member that secures the case to the wiring board and a ceiling. When the piezoelectric vibration device is mounted on the wiring board, the securing member defines a space between the ceiling and the wiring board to accommodate the piezoelectric transformer and the flexible board. Moreover, the piezoelectric transformer is suspended to the ceiling of the case by a holding member. This configuration provides a piezoelectric vibration device with which degradation of characteristics due to causes such as displacement of the piezoelectric vibrator or fluctuations in the pressing force applied by lead terminals is minimized.

A device for producing a non-thermal atmospheric pressure plasma and an active space including such a device are disclosed. In an embodiment a device includes a first housing, in which a piezoelectric transformer is arranged and a second housing, in which a control circuit is arranged, the control circuit configured to apply an input voltage to the piezoelectric transformer, wherein the first housing comprises a coating configured to eradicate irritant gases.

A system includes a piezoelectric capacitor assembly and signal processing circuitry coupled to the piezoelectric capacitor assembly. The piezoelectric capacitor assembly includes a piezoelectric member and piezoelectric capacitors located at respective lateral positions along the piezoelectric member. Each piezoelectric capacitor includes: (1) a respective portion of the piezoelectric member, (2) a first electrode, and (3) a second electrode. The first and second electrodes are positioned on opposite side of the piezoelectric member. The piezoelectric capacitors include piezoelectric force-measuring elements (PFEs). The PFEs are configured to output voltage signals between the respective first electrode and the respective second electrode in accordance with a time-varying strain at the respective portion of the piezoelectric member between the respective first electrode and the respective second electrode resulting from a low-frequency mechanical deformation. The signal processing circuitry is configured to read at least some of the PFE voltage signals.

Provided is a piezoelectric element according to the invention including a stacked body in which a piezoelectric layer and an internal electrode layer are stacked. In addition, the internal electrode layer contains at least one kind of element selected from palladium, nickel, platinum, gold, and silver, and copper, and the content of copper contained in the internal electrode layer is 1 to 50 at % in terms of a copper element.

Provided is a bulk acoustic wave resonator (BAWR). The BAWR may include an air cavity disposed on a substrate, a bulk acoustic wave resonant unit including a piezoelectric layer, and a reflective layer to reflect a wave of a resonant frequency that is generated from the piezoelectric layer.

A piezoelectric device that includes a base member having an opening therein and an upper layer supported by the base member. The upper layer includes a vibration portion at a location corresponding to the opening in the base member. The vibration portion includes a lower electrode, an intermediate electrode and an upper electrode that are spaced apart from one another in a thickness direction of the piezoelectric device. The upper layer includes a first piezoelectric layer disposed so as to be at least partially sandwiched between the lower electrode and the intermediate electrode, and a second piezoelectric layer disposed so as to overlap with the first piezoelectric layer and so as to be at least partially sandwiched between the intermediate electrode and the upper electrode. The first piezoelectric layer and the second piezoelectric layer are different in relative permittivity in the thickness direction of the piezoelectric device.

A method for producing a plurality of piezoelectric multilayer components is disclosed. In an embodiment, a method for producing a plurality of piezoelectric multilayer components includes grinding the piezoelectric multilayer components without an addition of an abrasive by rubbing the piezoelectric multilayer components against one another so that a material abrasion of the piezoelectric multilayer components is carried out.

A multilayer piezoelectric element that expands and contracts in response to an applied voltage includes external electrodes disposed on surfaces of an element body, internal electrodes connected to the external electrodes, and piezoelectric layers laminated alternately with the internal electrodes. An electrode material used for the internal electrodes or the external electrodes contains a base material composed of Ag and Pd in a weight ratio of 60/40 to 85/15 and Pt in an amount of 0.1% to 10% by weight based on the weight of the base material. Also included is a piezoelectric actuator including the piezoelectric element and a piezoelectric transformer including the piezoelectric element.

Circuitry for estimating a displacement of a piezoelectric transducer in response to a drive signal applied to the piezoelectric transducer, the circuitry comprising: monitoring circuitry configured to be coupled to the piezoelectric transducer and to output a sense signal indicative of an electrical signal associated with the piezoelectric transducer as a result of the drive signal; wherein the circuitry is configured to generate a difference signal based on the drive signal and the sense signal; and wherein the circuitry further comprises processing circuitry configured to apply at least one transfer function to the difference signal to generate a signal indicative of the displacement of the piezoelectric transducer.