An acoustic generator including a piezoelectric crystal, an impedance matching layer directly bonded to the crystal with Van der Waals forces.

A composite sensor includes a first sensor outputting a first sensor signal, a second sensor outputting a second sensor signal, a circuit board electrically connected to the first and second sensors, and a mount member having one surface on which the first and second sensors and the circuit board are disposed. The first and second sensors have respective input terminals to which respective input signals are inputted, and have respective output terminals from which the first and second sensor signals are outputted. When a virtual straight line passing respective centers of the first and second sensors parallel to an arrangement direction of the sensors is defined, the respective input terminals of the first and second sensors are disposed in one of two regions divided by the virtual line, and the respective output terminals of the first and second sensors are disposed in a remaining one of the two regions.

An element including: a first electrode; an intermediate layer made of a silicone rubber composition containing a silicone rubber; and a second electrode, where the first electrode, the intermediate layer, and the second electrode are disposed in this order, wherein a peak intensity ratio (1095±5 cm.sup.−1/1025±5 cm.sup.−1) of an infrared absorption spectrum of the intermediate layer varies along a vertical direction relative to a surface of the first electrode, and to a surface of the second electrode.

The force sensing device (1) comprising: a sheet (2) of piezoelectric; at least a first and a second interdigitated electrodes (5, 50) located on a first main face (3) and at least a third and fourth interdigitated electrodes (6, 60) located on a second main face (4) of the sheet (2), the first and third electrodes (5, 6) being aligned to each other along a normal stress direction (N), the second and fourth electrodes (50, 60) being aligned to each other along the normal stress direction (N); the piezoelectric material comprising first portions (100) facing the first and third electrodes (5, 6) interposed with second portions (101) facing the second and fourth electrodes (50, 60), the first portions (100) having bulk electric polarization with vector field (E) mostly oriented in alignment with the normal stress direction (N), the second portions (101) having bulk electric polarization with vector field (E) mostly oriented transversally to the normal stress direction (N).

A display device includes a touch panel; a display panel under the touch panel and displaying an image; a piezoelectric element under the touch panel and including an upper electrode, a lower electrode and a piezoelectric layer; and a rectifying circuit connected to the piezoelectric element.

A crystal element includes a vibration part, a holding part, an electrode part, and a recess that corresponds to a recess and/or protrusion. The vibration part has a pair of vibration-part main surfaces. The holding part is formed integrally with the vibration part to be connected to an outer edge of vibration part and has a pair of holding-part main surfaces and holding-part side surfaces. The electrode part is provided at the vibration-part main surfaces. The recess is located at the holding-part side surfaces.

An intelligent energy harvesting device, a voltage signal application system, and an energy management module thereof are disclosed. The intelligent energy harvesting device is used to transfer a signal to an application device. The intelligent energy harvesting device includes a power generation module, a battery and an energy management module. The power generation module generates a first voltage signal. The battery generates a second voltage signal. The energy management module is electrically connected to the power generation module and the battery for enabling the first voltage signal output from the power generation module to be used as a power signal to provide the application device, or enabling the first voltage signal output from the power generation module and the second voltage signal output from the battery collectively serves as the power signal to provide the application device.

A controller-transmitter transmits acoustic energy through the body to an implanted acoustic receiver-stimulator. The receiver-stimulator converts the acoustic energy into electrical energy and delivers the electrical energy to tissue using an electrode assembly. The receiver-stimulator limits the output voltage delivered to the tissue to a predetermined maximum output voltage. In the presence of interfering acoustic energy sources output voltages are thereby limited prior to being delivered to the tissue.

A controller-transmitter transmits acoustic energy through the body to an implanted acoustic receiver-stimulator. The receiver-stimulator converts the acoustic energy into electrical energy and delivers the electrical energy to tissue using an electrode assembly. The receiver-stimulator limits the output voltage delivered to the tissue to a predetermined maximum output voltage. In the presence of interfering acoustic energy sources output voltages are thereby limited prior to being delivered to the tissue.

A transducer includes a first piezoelectric layer; and a second piezoelectric layer that is above the first piezoelectric layer; wherein the second piezoelectric layer is a more compressive layer with an average stress that is less than or more compressive than an average stress of the first piezoelectric layer.