A squirter sonar transducer is provided as a body having a first end and a second end. The body is a cylindrical wall having a length and an inner diameter with a piezoelectric ring actuator disposed within the cylindrical wall. A baseplate is connected to the first end of the body and caps the first end. The second end of the body is open to define a resonator cavity within the body. The baseplate is made of a solid mass having a thickness of approximately fifty percent of the length of the cylindrical wall and has a recess approximately fifty percent of the thickness with a recess diameter equal to the inner diameter of the cylindrical wall.

An aerosol generating device includes: a housing; a first printed circuit board arranged to extend along one surface of the housing; and a second printed circuit board arranged in the housing, and on which a processor configured to generate a control signal is mounted, the second printed circuit board extending in a direction crossing a direction in which the one surface of the housing extends.

Methods and devices are described for driving ferroelectric perovskite oxide crystals to achieve polarization inversion with reduced coercivity. In some embodiments, the anisotropy in the potential energy surface of a ferroelectric material is employed to drive polarization inversion and switching with a reduced coercive field relative to uniaxial excitation. In some embodiments, polarization inversion with reduced coercivity is produced via the application of an electric field that exhibits a time-dependent orientation, in contrast with conventional uniaxial electrical excitation, thereby causing the central ion (and the crystal structure as a whole) to evolve along a lower-energy path, in which the central ion is driven such that it avoids the potential energy maximum. This may be achieved, for example, by applying at least two non-parallel time-dependent voltages (e.g. bias, potential) such that orientation of the electric field changes with time during the switching cycle.

A compact apparatus for atomisation of fluid samples comprises a sonotrode (11), placed so that an ultrasonic wave emitted by the sonotrode is directed through a channel (25) in a separate channel device (21) and reflected by from the interface (26) in a high-low impedance transition zone (Tz), so that a standing wave is formed within the channel. A positive air flow through the channel, driven by a pressure differential at each end of the channel, interacts with the working fluid or slurry being delivered by a fluid delivery device (30) to atomise it. The speed of the air flow and the dispersal, homogeneity, and size of particles in the slurry sample can be controlled by varying the shape of the channel outlet.

A novel mode of ultrasonic oscillation is generated in a Langevin ultrasonic transducer comprising a metal block, a metal block provided with a supporting means protruding in a ring shape on its side surface, and polarized piezoelectric elements fixed between these metal blocks, by connecting the ultrasonic transducer to a base via the supporting means, whereby supporting the ultrasonic transducer on the base in a restrained state, and applying to the piezoelectric elements a voltage having such frequency that the ultrasonic transducer generates an ultrasonic oscillation with back-and-forth motion in a direction perpendicular to plane surfaces of the piezoelectric elements which has no oscillation node within the ultrasonic transducer; this novel ultrasonic oscillation mode is utilized for performing ultrasonic machining methods as well as for ultrasonic transmission method.

An imaging system includes: a transceiver cell for generating a pressure wave and converting an external pressure wave into an electrical signal; and a control unit for controlling an operation of the transceiver cell. The transceiver cell includes: a substrate; at least one membrane suspending from the substrate; and a plurality of transducer elements mounted on the at least one membrane. Each of the plurality of transducer elements has a bottom electrode, a piezoelectric layer on bottom electrode, and at least one top electrode on the piezoelectric layer. Each of the plurality of transducer element generates a bending moment in response to applying an electrical potential across the bottom electrode and the at least one top electrode and develops an electrical charge in response to a bending moment due to the external pressure wave.

According to one embodiment, a transducer includes a first electrode, a second electrode, a third electrode, a first piezoelectric portion, and a second piezoelectric portion. A resistor and an inductor are connected to the second electrode. The first piezoelectric portion is provided between the first electrode and the third electrode. The second piezoelectric portion is provided between the second electrode and the third electrode. A ratio of the absolute value of a difference between a first resonant frequency and a second resonant frequency to the first resonant frequency is 0.29 or less. The first resonant frequency is mechanical. The first resonant frequency is of the first piezoelectric portion and the second piezoelectric portion. The second resonant frequency is of a parallel resonant circuit. The parallel resonant circuit includes an electrostatic capacitance, the inductor, and the resistor. The electrostatic capacitance is between the second electrode and the third electrode.

An ultrasonic transducer and a method for a transmitting an acoustic wave using an ultrasonic transducer comprising a membrane; two or more patterned top electrodes; a pMUT array, wherein the patterned top electrode is arranged as row pin selector and column selector in an N?N array; the pMUT array having N+N electrical contacts; a single unpatterned bottom electrode; a row and column where the electrode is at equal or opposite polarities; and a AC driving voltage is applied to top electrodes with a phase difference of zero or is applied to one electrode to transmit the ultrasonic wave.

A transceiver includes an array of pMUT elements, where each pMUT element includes: a substrate; a membrane suspending from the substrate; a bottom electrode disposed on the membrane; a piezoelectric layer disposed on the bottom electrode; and a first electrode disposed on the piezoelectric layer. Each pMUT element exhibits one or more modes of vibration.

An imaging system includes: a transceiver cell for generating a pressure wave and converting an external pressure wave into an electrical signal; and a control unit for controlling an operation of the transceiver cell. The transceiver cell includes: a substrate; at least one membrane suspending from the substrate; and a plurality of transducer elements mounted on the at least one membrane. Each of the plurality of transducer elements has a bottom electrode, a piezoelectric layer on bottom electrode, and at least one top electrode on the piezoelectric layer. Each of the plurality of transducer element generates a bending moment in response to applying an electrical potential across the bottom electrode and the at least one top electrode and develops an electrical charge in response to a bending moment due to the external pressure wave.