A device includes a pair of substrate layer corresponding to a carrier substrate, an intermediary layer disposed on the pair of substrate layers, a cavity region disposed between the pair of substrate layers underneath the intermediary layer, a piezoelectric layer including a lithium-based film disposed on the intermediary layer, and a plurality of interdigital transducer electrodes disposed on the piezoelectric layer. The plurality of interdigital transducer electrodes includes an outer signal electrode, an inner signal electrode, an outer ground electrode and an inner ground electrode.

A touch feedback and sensing device includes a circuit board, a piezoelectric ceramic actuator on the circuit board; and at least one strain sensor on the circuit board. The piezoelectric ceramic actuator includes a piezoelectric ceramic block, a cathode and an anode on the piezoelectric ceramic block. Different voltages are applied to the cathode and the anode to vibrate the piezoelectric ceramic block. The circuit board vibrates with vibration of the piezoelectric ceramic block. The at least one strain sensor is configured to detect and monitor vibration of the circuit board.

Aspects of this disclosure relate to driving a capacitive micromachined ultrasonic transducer (CMUT) with a pulse train of unipolar pulses. The CMUT may be electrically excited with a pulse train of unipolar pulses such that the CMUT operates in a continuous wave mode. In some embodiments, the CMUT may have a contoured electrode.

An ultrasonic transducer positionable in a wellbore environment may include a piezoelectric material layer, a protective layer, and connecting plate positioned between the piezoelectric material layer and the protective layer. The piezoelectric material layer may be formed as a plurality of columns of piezoelectric material for detecting a characteristic of the wellbore environment during a drilling operation. The protective layer may be positionable between the piezoelectric material layer and an acoustic medium in the wellbore environment. The connecting plate may be positioned between the piezoelectric material layer and the protective layer. The connecting plate may have a coefficient of thermal expansion (CTE) in a range between the CTE of the piezoelectric material layer and that of the protective layer, and an acoustic impedance in a range between the acoustic impedance of the piezoelectric material layer and that of the protective layer.

Aspects of this disclosure relate to driving a capacitive micromachined ultrasonic transducer (CMUT) with a pulse train of unipolar pulses. The CMUT may be electrically excited with a pulse train of unipolar pulses such that the CMUT operates in a continuous wave mode. In some embodiments, the CMUT may have a contoured electrode.

A display device and a manufacturing method thereof are provided. The display device includes a first substrate, a second substrate, first signal lines, second signal lines, a first insulation layer, active components, a display medium, and ultrasonic transducers. The first insulation layer is located between the first signal lines and the second signal lines. Cavities are located in the first insulation layer having thin films located on the cavities. Each of the ultrasonic transducers includes first and second electrodes. A first electrode and a corresponding first signal line belong to a same layer and are electrically connected with each other. A second electrode and a corresponding second signal line belong to a same layer and are electrically connected with each other. A corresponding cavity and a corresponding thin film are sandwiched between the first and second electrodes.

An imaging device includes a two dimensional array of piezoelectric elements. Each piezoelectric element includes: a piezoelectric layer; a bottom electrode disposed on a bottom side of the piezoelectric layer and configured to receive a transmit signal during a transmit mode and develop an electrical charge during a receive mode; and a first top electrode disposed on a top side of the piezoelectric layer; and a first conductor, wherein the first top electrodes of a portion of the piezoelectric elements in a first column of the two dimensional array are electrically coupled to the first conductor.

An H.sub.2S sensor includes at least one acoustic wave transducer and a film having a polymer matrix. The polymer matrix includes carboxylate functional groups and lead or zinc cations. The film may have a thickness of between a hundred nanometres and a 2 microns The H.sub.2S sensor optionally includes an antenna to remotely interrogate the H.sub.2S sensor.

An ultrasonic transceiver includes: a piezoelectric body including opposing surfaces having a first electrode and a second electrode respectively, piezoelectric body being segmented into a plurality of elements by a groove recessed from a surface having first electrode among the opposing surfaces; conductor electrically connected to first electrode on each of elements. The ultrasonic transceiver further includes reinforcement section provided in a part of second electrode, the part corresponding to a bottom of the groove. With this configuration, a decrease in a strength of piezoelectric body in the bottom of the groove, which is caused by a groove provided in piezoelectric body, can be prevented and occurrence of a crack can be prevented.

The present invention provides an ultrasonic fingerprint recognition module and a display panel. Advantages of the present invention are that a vibration absorbing layer can absorb mechanical energy of a piezoelectric thin film layer such that a number of cycles of later ultrasound is significantly reduces to extremely increase a vertical resolution of ultrasound fingerprint recognition and overall recognition effect and precision.