Ultrasound devices and systems are disclosed in which cooling of an active acoustic element of an ultrasound transducer is achieved via an electrically conductive member that extends beyond a proximal side of the active acoustic element to contact a heat exchanger. The electrically conductive member delivers electrical driving signals to the active acoustic element while conducting heat to the heat exchanger. A region of the proximal surface of the active acoustic element that is free from contact with the electrically conductive member may also absent from contact with a liquid or a solid, thereby facilitating reflection of ultrasound energy. The heat exchanger may include an electrically insulating fluid that contacts the electrically conductive member to remove the heat conducted through the electrically conductive member. The active acoustic element may be a multilayer lateral mode element, and the electrically conductive member may form an electrode of the lateral mode element.

A piezoelectric element includes a piezoelectric element main body as a laminated body of a first electrode layer, a piezoelectric layer disposed on the first electrode layer, and a second electrode layer disposed on the piezoelectric layer, and a metal layer disposed on the second electrode layer via an insulating layer, the piezoelectric layer extends from an inner side of at least a part of an overlapping part of an outer peripheral edge of the second electrode layer overlapping an outer peripheral edge of the piezoelectric element main body to an outer side, and the metal layer and the insulating layer extend from an inner side of at least a part of the overlapping part to an outer side to overlap the piezoelectric layer on an outer side of an outer peripheral edge of the second electrode layer.

A method of evaluating a natural frequency of a piezoelectric vibrator including a vibrating membrane and a piezoelectric element, includes: transmitting a drive signal to the piezoelectric element for a certain period of time so as to allow the vibrating membrane to vibrate; acquiring information about a power-generating wave of the piezoelectric vibrator after stopping the transmission of the drive signal to the piezoelectric element; and determining a frequency of the drive wave at which a value of a voltage of the power-generating wave is maximum as the natural frequency of the piezoelectric vibrator, based on the information about the power-generating wave.

Planar phased ultrasound transducer including a first layer including a sheet of piezoelectric material, a piezo frame surrounding an outer perimeter of the sheet of piezoelectric material, and an epoxy material placed between the piezo frame and the sheet of piezoelectric material. The transducer includes a flex frame secured to a back side of the first layer.

A display apparatus includes a first substrate; a pixel array layer disposed on the first substrate and defining a display area and a non-display area, and the pixel array layer including a pixel signal line; a second substrate disposed opposite to the first substrate; a display medium disposed between the first substrate and the second substrate; and an ultrasonic element (UE) layer, disposed on the second substrate and including an ultrasonic signal line. Within at least parts of the display area corresponding to the ultrasonic element layer, a projection area on the first substrate by projecting the ultrasonic signal line along the normal direction of the first substrate at least partially overlaps with another projection area on the first substrate by projecting the pixel signal line along the normal direction of the first substrate.

A biodegradable and biocompatible piezoelectric nanofiber platform for medical implant applications, including a highly sensitive, wireless, biodegradable force sensor for the monitoring of physiological pressures, and a biodegradable ultrasonic transducer for the delivery of therapeutics or pharmaceuticals across the blood-brain barrier.

An ultrasound probe including: a circuit substrate (23) having a recess in a first region on the lower surface side; a buffer layer (400) composed of an insulating material on a second region different from the first region of circuit substrate (23); and an element array layer (22) including a first piezoelectric element (100) for ultrasound transmission formed in the first region of the circuit substrate (23) without the buffer layer (400), and a second piezoelectric element (200) for ultrasound reception formed in the second region of the circuit substrate (23) on the buffer layer (400). The first piezoelectric element (100) vibrates in a flexural vibration mode on the circuit substrate (23), and the second piezoelectric element (200) vibrates in a thickness vibration mode on the circuit substrate (23).

A focused ultrasonic transducer includes a piezoelectric substrate having a first face and a second face, a back metal layer disposed over the first face, and a patterned metal layer disposed over the second face. The patterned metal layer includes a first plurality of concentric ring electrodes wherein each of the first plurality of concentric ring electrodes are wired to be individually accessible. A controller actuates a subset of the concentric ring electrodes such that electrical control of focal length is achieved by selecting a group of electrodes to actuate so that acoustic waves generated from selected electrodes arrive at a desired focal length in-phase and interfere constructively to create a focal spot of high acoustic intensity. The patterned metal layer optionally includes a first central electrode that is surrounded by the first plurality of concentric ring electrodes.

A piezoelectric device includes a piezoelectric film having a first surface in contact with a vibrating film and a second surface on the opposite side to the first surface, first and second electrodes that are provided on the second surface of the piezoelectric film and that are disposed at positions away from each other and are short-circuited to each other at a position away from the piezoelectric film, and a third electrode that is provided between the first and second electrodes on the second surface of the piezoelectric film and is disposed at a position away from the first and second electrodes. At least parts of the contours of end portions of the first and second electrodes are defined in parallel to side portions of the third electrode.

A sensor includes a first element part and a second element part. The first element part includes a first upper main electrode part, a first upper sub electrode part and a first lower electrode layer. In the second element part, a configuration of electrodes is inverse to that of the first element part. It includes a second lower main electrode part, a second lower sub electrode part and a second upper electrode layer. The first upper main electrode part and the second lower sub electrode part are connected. The first upper sub electrode part and the second lower main electrode part are connected. The first lower electrode layer and the second upper electrode layer are connected.