Provided is a capacitive micromachined ultrasonic transducer (CMUT) including a substrate, a top electrode provided on the substrate to be spaced apart from the substrate, a supporter made of an insulating material and coupled between the substrate and an edge of the top electrode to support and fix the edge of the top electrode and to define a gap between the substrate and the edge of the top electrode, and a plurality of nanoposts having both ends coupled and fixed to the substrate and the top electrode in the gap, and being compressible and stretchable in a longitudinal direction to at least vertically move the top electrode when power is applied to the top electrode.

A signal generator generates an electrical signal that is sent to an amplifier, which increases the power of the signal using power from a power source. The amplified signal is fed to a sender transducer to generate ultrasonic waves that can be focused and sent to a receiver. The receiver transducer converts the ultrasonic waves back into electrical energy and stores it in an energy storage device, such as a battery, or uses the electrical energy to power a device. In this way, a device can be remotely charged or powered without having to be tethered to an electrical outlet.

A miniature rangefinder includes a housing, a micromachined ultrasonic transducer, and signal processing circuitry. The housing includes a substrate and a lid. The housing has one or more apertures and the micromachined ultrasonic transducer is mounted over an aperture. The micromachined ultrasonic transducer may function as both a transmitter and a receiver. An integrated circuit is configured to drive the transducer to transmit an acoustic signal, detect a return signal, and determine a time of flight between emitting the acoustic signal and detecting the return signal.

The present invention relates to a driver device (40) for driving a load (52) having a plurality of separate capacitive load elements (52), in particular an ultrasound transducer having a plurality of transducer elements (52), comprising: input terminals (44, 46) for connecting the driver device (40) to power supply (48); a plurality of output terminals (50) each for connecting the driver device (40) to one of load elements (52), a first controllable switch (54) connected to a first of the input terminals (44), and a plurality of driving elements (42) each having a second controllable switch (60) and a resistor (58) connected in series to each other, wherein each of the driving elements (42) is connected in series with the first controllable switch (54) and to a second of the input terminals (46), and wherein each of the output terminals (50) is connected to one of the driving elements (42) for powering the load elements (52).

In certain examples, methods and circuit-based apparatuses involve or are directed to a transducer to be operated via at least one resonance frequency of the transducer, and to a tunable circuitry (e.g., negative capacitance control and/or resistance control) to change the resonance frequency and/or a bandwidth around the resonance frequency. In more specific aspects, a tunable negative capacitance control may be used to change the resonance frequency and/or damping resistance control without degrading a degree of sensitivity provided by the transducer. Another example, specific to a method, involves: operating a transducer, coupled to a negative capacitance, at a resonance frequency of the transducer; and changing or setting a characteristic concerning the resonance frequency by using a tunable circuit to effect a change of the resonance frequency and/or a bandwidth around the resonance frequency.

An ultrasound system has a set of CMUT transducer devices and drive electronics for operating a selected device of the set. The drive electronics is shared between all devices of the set. Selection is made by using a set of switches (178), with a respective switch between a DC bias output (166) of the drive electronics and an associated input (160) of each device. This provides a simple way to provide a selection function between the drive electronics and multiple ultrasound devices. In this way, the number of devices may be scale up, to cover a larger area, but without scaling the cost of the system by the same degree.

Various methods and systems are provided for increasing a fractional bandwidth of an ultrasound device, for use in both low and high frequency applications. In one example, where a transducer array includes one or more transducer elements comprising a plurality of capacitive micromachined ultrasound transducers (cMUT), the fractional bandwidth may be advantageously increased by applying different bias voltages to different groupings of cMUTs within each transducer element. A ratio between the different bias voltages may be optimized to maximize the fractional bandwidth. In another example, the different bias voltages may be configured to operate a first grouping of cMUTs in a transmit mode, and a second grouping of cMUTs in a receive mode.

An ultrasound array system has an array of transducer elements made from bias-sensitive material, each transducer element comprising at least a first sub-element and a second sub-element. A series of column electrodes is patterned in columns on a first surface of the array of transducer elements. A series of row electrodes is patterned in rows on a second surface of the array. The rows are at an angle relative to the columns, wherein, for each transducer element, the first sub-element and the second sub-element are connected to different row electrodes. A controller is connected to selectively apply voltage signals to the series of column electrodes and the series of row electrodes. The controller is programmed to apply a first voltage signal to the first sub-element and a second voltage signal to the second sub-element that is distinct from the first voltage signal.

The electronic device is arranged for generation of an audible alarm or music. It includes a coil or inductor and a buzzer provided with a capacitor connected in series with the coil. When the electronic device is actuated, the buzzer generates the audible alarm or music. The electronic device further includes, in a feedback loop, a derivative circuit connected to a connection node between the coil and the capacitor, to produce a derivative of the signal from the capacitor, and a comparator for comparing a derivative signal from the derivative circuit with a reference voltage. The comparator supplies an output signal to the coil to amplify the signal across the capacitor, so that the buzzer generates at least one audible alarm.

An ultrasonic vibration sub-element including a substrate, a ground layer, a first insulation layer, a second insulation layer, a first electrode layer, a third insulation layer, and a second electrode layer is provided. The first electrode layer is configured to receive a direct current voltage. The second electrode layer is configured to receive an alternating current signal. Before the ultrasonic vibration sub-element is driven, there is a cavity between the first insulation layer and the second insulation layer. When the ultrasonic vibration sub-element is driven, the first electrode layer receives the direct current voltage and is configured to at least drive the second insulation layer to shrink toward the cavity. The second electrode layer receives the alternating current signal and is configured to at least drive the third insulation layer to vibrate. An ultrasound probe is also provided.