A multilayer body includes a piezoelectric body and a first acoustic matching layer in direct or indirect contact with the piezoelectric body. The first acoustic matching layer includes a plastic foam containing a plurality of closed pores. An average pore size of the closed pores is not smaller than 1 m and not larger than 100 m. The first acoustic matching layer has a density of not less than 10 kg/m.sup.3 and not more than 100 kg/m.sup.3.

A vibration device includes a substrate that contains movable ions, an element unit that has a movable portion which is displaceable from the substrate, and a conductor layer that is disposed on a side of the substrate which is opposite to the element unit. When a potential of the movable portion is set to E1 and a potential of the conductor layer is set to E2, |E1E2|<|E1| is satisfied. In a plan view obtained in a direction where the conductor layer, the substrate, and the element unit are juxtaposed with one another, the conductor layer overlaps at least a portion of the movable portion.

A fluid device includes a chamber that is provided with an inlet and an outlet opened at different positions on an X axis and is formed with a flow path space in which a fluid is caused to flow from the inlet to the outlet, a first ultrasonic element configured to generate a standing wave in a direction along an X axis in the fluid in the chamber, a driver configured to drive the first ultrasonic element, and a drive controller configured to control the driver such that a drive voltage applied to the first ultrasonic element is reduced over time.

A system for processing biological or other samples includes an array of transducer elements that are positioned to align with sample wells in a microplate. Each transducer element produces ultrasound energy that is focused towards a well of the microplate with sufficient acoustic pressure to cause inertial cavitation. In one embodiment, the transducers are configured to direct ultrasound energy into cylindrical wells. In other embodiments, the transducer elements are configured to direct ultrasound energy into non-cylindrical wells of a microplate.

An excitation device includes an output circuit to output a drive signal having a frequency component to drive a piezoelectric element to vibrate an object using a vibrating body, and a control circuit including vibration modes to control the output circuit to apply to the piezoelectric element a drive signal having a frequency based on a resonant frequency of a vibrator including the object, the vibrating body, and the piezoelectric element, the modes including a predetermined vibration mode in which the frequency of the drive signal is about 1/(2n+1) times or about (2n+1) times the resonant frequency of the vibrator, and n is a positive integer.

An electronic device (1) includes a touch panel display (2), a speaker (3), and a piezo actuator (4). The speaker (3) outputs a sound based on a first sound signal corresponding to a range of a prescribed frequency or more. The piezo actuator (4) is provided on the touch panel display (2), and is deformed in response to at least one of a second sound signal corresponding to a range of less than the prescribed frequency and a control signal for haptics feedback based on a predetermined vibration pattern to vibrate the touch panel display (2).

Disclosed are systems, devices and methods for providing fingerprint sensors based on ultrasound imaging techniques in electronic devices and fabrication techniques for producing ultrasound-based fingerprint sensors. In some aspects, an ultrasound fingerprint sensor device includes an intermediate layer coupled to a base chip including an integrated circuit having conducive contacts at a surface of the base chip, the intermediate layer including an insulation layer formed on the base chip and a corresponding array of channeling electrode structures coupled to the conductive contacts and passing through the insulation layer, in which the channeling electrodes terminate at or above a top surface of the insulation layer to provide bottom electrodes; a plurality of ultrasonic transducer elements including an acoustic transducer material coupled to the bottom electrodes; and a plurality of top electrodes positioned on the ultrasonic transducer elements.

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.

The present invention relates a power ultrasound device for fluids processing. An ultrasonic resonator comprises: an exciter section having a longitudinal axis and dimensioned to be resonant in a direction along the longitudinal axis when the exciter section is energized with high frequency vibrations; and a radiator section having a connection stub and coupled to the exciter section through the connection stub, wherein the radiator section is configured to receive the vibrations from the exciter section and transmit the vibrations as acoustic waves, wherein an axial length of the exciter section is less than a half-wavelength, wherein the connection stub completes the half-wavelength when coupled to the excited section to allow the ultrasonic resonator operate in resonance at design frequency. The radiator section includes a radiator body having at least three sides to provide a plurality of external radiating surfaces, and two opposite faces having a plurality of orifices formed therein, wherein walls of the orifices are configured to provide a plurality of internal radiating surfaces, and wherein the internal and the external surfaces are configured to transmit the vibrations as acoustic waves.

The present disclosure provides three-dimensional (3D) printing systems, apparatuses, software, and methods for the production of at least one requested 3D object. The 3D printer includes a material conveyance system, filtering system, and unpacking station. The material conveyance system may comprise transporting pre-transformed (e.g., powder) material against gravity, by directional conveyance (e.g., of a bounceable platform), and prolonged uninterrupted sieving while minimizing sieve blinding. The 3D printing described herein comprises facilitating non-interrupted (e.g., curbs interruptions of) material dispensing through a component of the 3D printer, such as a layer dispenser.