A vibration device that includes a first elastic plate having a first end portion and a second end portion, and a first surface and a second surface facing each other and connecting the first and second end portions. A second elastic plate is laminated to the second end portion of the first elastic plate, and a piezoelectric vibration element is provided on at least one of the first surface and the second surface of the first elastic plate. On a portion where the first elastic plate and the second elastic plate are laminated, a first bonding portion and a second bonding portion that bond the first elastic plate and the second elastic plate to each other are provided. The second bonding portion is located closer to the first end portion than the first bonding portion.

Described herein is a method of bonding a piezoelectric substrate to a support substrate to form a composite substrate. The piezoelectric substrate has one surface which is positively polarized, and a second surface which is negatively polarized. The method described herein includes the steps of bonding the positively polarized surface of the piezoelectric substrate to one surface of the support substrate by a direct bonding method.

Provided is a method of manufacturing an ultrasound probe. The method includes: preparing a backing layer having first and second surfaces with different heights due to forming a groove in the backing layer, wherein first and second electrodes are exposed on the first and second surfaces, respectively; forming a third electrode that is in contact with the first electrode; forming a base piezoelectric unit on the third electrode, the base piezoelectric unit including a piezoelectric layer; forming a piezoelectric unit by removing an upper region of the base piezoelectric unit; and forming a fourth electrode on the backing layer and the piezoelectric unit.

A sensor (1) which consists of a first electrode (3a), a ferroelectric layer (2) and a second electrode (3b) is described. The second electrode (3b) is connected to ground and the ferroelectric layer (2) is arranged between the first and second electrodes (3a, 3b).

An embodiment piezoelectric element includes a piezoelectric composite layer including a polymer and a piezoelectric ceramic, a backing layer disposed on a rear surface of the piezoelectric composite layer and configured to limit vibration of the piezoelectric composite layer, and an adhesive layer bonding the piezoelectric composite layer and the backing layer.

Various methods and systems are provided for a multi-frequency transducer array. In one example, the transducer array includes an element formed of one or more sub-elements, at least one sub-element having a different resonance frequency. A frequency range of the transducer array may thereby be broadened.

Various methods and systems are provided for a multi-frequency transducer array. In one example, the transducer array includes an element formed of one or more sub-elements, at least one sub-element having a different resonance frequency. A frequency range of the transducer array may thereby be broadened.

An ultrasonic sensor, which is installed on a test device, includes a shell, one end is open, the other end is closed surface; a cover sheet, bonded to the open end of the shell; a copper foil, a lower surface of the copper foil is bonded to an inner bottom surface of the closed surface of the shell; a piezoelectric chip, a lower surface of the piezoelectric chip is bonded to a upper surface of the copper foil, and when the test device vibrates, the piezoelectric chip converts a vibration signal into a voltage response signal; a cable, a positive electrode is welded on a upper surface of the piezoelectric chip, and a negative electrode is welded on the upper surface of the copper foil, configured to connect to an external detection device and transmit the voltage response signal to the external detection device.

A magneto-electric converter capable of converting a variation in magnetic field into a potential difference between two electrical terminals includes a support layer comprising two electrical terminals; a stack disposed on the support layer of a first layer made from a magnetostrictive material defining the reference plane and of a second layer made from a piezoelectric material having a polarization axis in the plane defined by the second layer, parallel to the reference plane; the second layer comprising electrodes; and a means for electrical connection of the electrodes to the electrical terminals.

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.