An ultrasound transducer assembly includes a housing; a wedge-shaped acoustic modal convertor (AMC) in the housing with a first surface exposed by an opening in the housing, and a second surface that meets the first surface at a tip located in the housing, and extends from the tip at an angle into the housing, wherein the second surface has a recessed portion formed therein, wherein the second surface of the AMC is oriented at a specific oblique angle to the first surface of the AMC; and a piezoelectric ultrasound transducer disposed in the recessed portion of the second surface of the AMC, wherein the piezoelectric ultrasound transducer is connected to an electrically tuned circuit that resonates at a specific frequency and has a finite bandwidth.

An acoustic levitation system contains an acoustic transducer array emitting acoustic energy of periodically varying intensity. The acoustic transducer array includes a set of transducer elements arranged on a surface extending in at least two dimensions. The transducer elements are controllable in response to a control signal so as to emit the acoustic energy at a wavelength and a phase delay determined by the control signal. A controller generates the control signal such that an acoustic channel comprising one or more high-pressure region enclosing a continuous pressure minimum region that extends along a defined channel path from a start position to an end position. The continuous pressure minimum region enclosed by the one or more high-pressure region represents a trap volume suitable for carrying, levitating and translating matter in a contactless manner.

The present disclosure relates to circuitry for driving a load. The circuitry comprises driver circuitry configured to generate a drive signal, based on an input signal to the driver circuitry, for driving the load, and commutator circuitry for coupling the driver circuitry to the load. The commutator circuitry is configured to alternate between commutation states in response to a level of the drive signal meeting a drive signal threshold or in response to a level of the input signal meeting a first input signal threshold. The circuitry is configured to apply an offset to the input signal when the input signal is below a second input signal threshold so as to increase a minimum level of the drive signal above the drive signal threshold or to increase a minimum level of the input signal above the first input signal threshold.

Provided is a probe which transmits an ultrasonic wave to a diagnostic site and receives a reception signal which is a reflected wave. The probe includes: a plurality of transducers; a plurality of low-noise amplifying circuits respectively corresponding to the plurality of transducers; and a single differential converter which converts a control signal rising with the elapse of time to a first bias signal rising with the elapse of time and a second bias signal falling with the elapse of time to control the plurality of low-noise amplifying circuits, and the low-noise amplifying circuit includes an attenuator which attenuates: an electric signal from the transducer; a first amplifying circuit which sets the first bias signal as a bias and amplifies an output signal of the attenuator to be gradually increased with the elapse of time; a second amplifying circuit which sets the second bias signal as a bias and amplifies the output signal of the attenuator to be gradually reduced with the elapse of time; and a subtractor which subtracts an output of the first amplifying circuit and an output of the second amplifying circuit.

An system, and method are disclosed for harmonic modulation of standing wavefields for spatial focusing, manipulation, and patterning of particles, cells, powders, aerosols, colloids, and solids using a multifrequency wave source, a chamber a control module and an analysis module to generate standard wavefields useful for tissue engineering, micro fabrication, therapeutic treatment, and diagnostic tests.

Provided is a portable audio equipment comprising: a neckband-shaped housing having one side open; a vibration unit including a plurality of vibration modules provided in at least two regions corresponding to both sides of the housing; and a control unit for sensing a control signal including information on a vibration pattern for each of the plurality of vibration modules and controlling the plurality of vibration modules to output the vibration pattern, wherein the vibration pattern is related to event information that is generated in an external terminal device.

An ultrasound transducer array is incorporated in a light-weight, conformable, and wearable patch that may be used to deliver, monitor, and control localized transcranial focused ultrasound (tFUS). The patch may include full-duplex transmit-receive circuitry that may be used for continuous monitoring of transcranial focused ultrasound (tFUS) application. The circuitry may include a circulator. The ultrasound transducer array may be coupled to an aperture interface having irregularly sized or shaped channel conductors to provide a coarse aperture for the array. The coarse aperture may be designed using a method that provides a reduced channel count.

Techniques are disclosed for systems and methods to provide transmission signal shaping for transmission signal-based sensor systems, such as radar and/or sonar sensor systems. A low noise signal shaping transmitter includes a digital to analog converter configured to convert a digital shaping control signal to an analog shaping control signal, a signal shaping circuit configured to convert the analog shaping control signal into a shaped voltage, and a power amplifier configured to provide a shaped transmission signal based on the shaped voltage and a digital transmission control signal. Each element of the transmitter may be formed from relatively slow switching analog and/or digital circuitry components. Resulting shaped transmission signals may be used to excite radar antennas, sonar transducers, sound cells, and/or other elements of sensor systems.

This application relates to methods and apparatus for driving a transducer with switching drivers. A driver circuit has first and second switching drivers for driving the transducer in a bridge-tied-load configuration, each of the switching drivers having a respective output stage for controllably switching the respective driver output node between high and low switching voltages with a controlled duty cycle. Each of switching drivers is operable in a plurality of different driver modes, wherein the switching voltages are different in said different driver modes. A controller controls the driver mode of operation and the duty cycle of the switching drivers based on the input signal. The controller is configured to control the duty cycles of the first and second switching drivers within defined minimum and maximum limits of duty cycles; and to transition between driver modes of operation when the duty cycle of one of the switching drivers reaches a duty cycle limit.

This bodily vibration generation device can be mounted to a bodily sensation presentation apparatus and generates, with a simple configuration, suitable vibration corresponding to a sound so that a user bodily senses the vibration. This device has: an electromagnetic actuator that causes, by an inputted drive signal, a movable body being supported so as to be elastically vibratable with respect to a fixed body, to vibrate by driving same in one direction of the vibration directions thereof; an AC signal input unit for inputting an AC signal; and a rectification unit that performs half-wave rectification of the AC signal and outputs the AC signal to the electromagnetic actuator as the drive signal.