According to one embodiment, a drive circuit includes a first circuit part. The first circuit part includes a first detecting part, a second detecting part, a first circuit, and a second circuit. The first detecting part is configured to detect a first piezoelectric element current flowing in a first piezoelectric element, and output a first detection signal corresponding to the first piezoelectric element current. The second detecting part is configured to detect a first capacitance element current flowing in a first capacitance element, and output a second detection signal corresponding to the first capacitance element current. The first circuit includes a first input terminal and a second input terminal. The first circuit is configured to apply a first drive signal to the first piezoelectric element and the first capacitance element. The second circuit is configured to supply a first differential signal to the second input terminal.

An MEMS airborne ultrasonic transducer system operating on a thermoacoustic principle to determine brain haemorrhage, includes: an RF transmitter and ultrasound receiver systems to transmit RF energy and receive ultrasound wave, respectively, an RF transmitter system having an RF signal generator, an RF amplifier and a horn antenna, and an ultrasound receiver system having a lock-in amplifier, a DC supply and two ultrasonic transducer arrays wirebonded to low noise amplifier (LNA) chips. The MEMS airborne ultrasonic transducer system determines brain haemorrhage based on detecting RF-induced, blood-originating, thermoacoustic ultrasound wave at the pulse modulation frequency.

A method of fabricating and controlling a thick-film transducer array for steering and focusing ultrasonic waves within a substrate volume is provided. A ceramic film composition can be coated on a substrate volume in one or more layers. The ceramic film can be masked with a plastic sheet out of which an electrode pattern is cut. Conductive electrode material can be applied to the pattern to create a transducer array that can be polarized with an applied electric field. A method of controlling a thick-film transducer array comprises exciting one or more array elements to generate a wavefield in a substrate volume, the wavefield can be reflected by features within the substrate volume, one or more array elements can receive reflected wavefield signals, and images of the insonified substrate volume can be generated.

In one embodiment, a transducer comprises a first piezoelectric stack comprising a piezoelectric material; a first layer in contact with the piezoelectric stack; and a base structure beneath the first layer. The first layer has a first displacement between a first portion of the base structure and the first layer, and the first displacement is configurable by a first bias voltage received by the transducer.

A transducer device may include an active layer having a proximal surface and a backing layer having a distal side and a proximal side, the distal side being adjacent to the proximal surface. The proximal side may include (1) at least one first reflective surface approximately parallel to the proximal surface and positioned a first distance from the proximal surface, and (2) at least one second reflective surface approximately parallel to the proximal surface and positioned a second distance from the proximal surface, the second distance being different than the first distance.

A system and method from improving the image quality achievable with an ultrasound transducer by using a composite aperture for receiving ultrasound echoes. By using two receive cycles per vector, twice as many transducers may be used for receiving ultrasound imaging data than there are physical channels available in the ultrasound probe. An ultrasound probe utilizing a composite aperture can achieve high image quality from a system have reduced power, size, cost and complexity.

An ultrasonic probe includes: a plurality of transducers that perform electro-acoustic conversion on transmission pulses applied thereto to generate a transmission beam of ultrasonic waves; and transmission/reception circuits that are provided so as to correspond to each of the plurality of transducers. The transmission/reception circuits set transmission/reception switching timings at which the ultrasonic waves are switched from transmission to reception independently for each of the plurality of transducers.

An ultrasonic device includes: a substrate provided with a first opening and a second opening; a support film that is provided on the substrate and blocks the first opening and the second opening; a transmitting piezoelectric film that is provided on the support film at a position which overlaps the first opening when viewed in a thickness direction of the substrate and is interposed between a pair of electrodes in the thickness direction of the substrate; and a receiving piezoelectric film that is provided on the support film at a position which overlaps the second opening when viewed in the thickness direction of the substrate and is interposed between a pair of electrodes in the thickness direction of the substrate. In the thickness direction of the substrate, a thickness dimension of the transmitting piezoelectric film is smaller than a thickness dimension of the receiving piezoelectric film.

The present invention is a piezoelectric actuator drive method, a piezoelectric actuator drive circuit, and a piezoelectric actuator drive system capable of causing a piezoelectric element to vibrate in a maximum amplitude state. The piezoelectric actuator drive circuit includes: an obtainment unit that obtains operation information pertaining to operation of the piezoelectric element in a period that is a part of one cycle of a drive cycle in which the piezoelectric element is driven; and a control unit that performs feedback control of a drive parameter for driving the piezoelectric element based on the operation information.

An ultrasonic sensor includes an ultrasonic transducer; a first voltage output circuit to output a transmission voltage signal that oscillates between a first high voltage and a first low voltage, supplied to a first terminal of the ultrasonic transducer; a reception circuit to detect a voltage signal generated at a second terminal of the ultrasonic transducer; and the second voltage output circuit to output a second high voltage smaller than the first high voltage. The first voltage output circuit includes a first switching unit to perform switching between supplying the transmission voltage signal in ultrasonic transmission; and fixing a potential of the first terminal in ultrasonic reception. The second voltage output circuit includes a second switching unit that performs switching between supplying the second high voltage to the second terminal in ultrasonic transmission; and electrically separating the second voltage output circuit from the second terminal in ultrasonic reception.