A method includes determining, for a piezoelectric cantilever-type transducer of a distributed mode loudspeaker adapted to cause vibration of a load, a subset of frequencies from a range of frequencies at which to output vibrations, in which the transducer includes two or more electrode pairs positioned along a length of the transducer and each electrode pair including a first electrode on a first side of a piezoelectric layer of the transducer and a second electrode on a second side of the piezoelectric layer of the transducer that is opposite to the first side; selecting, for the subset of frequencies, a respective input voltage for each of the two or more electrode pairs based on a relative position of each pair on the transducer; and applying the respective input voltage to each of the two or more electrode pairs to cause the transducer to generate a vibrational force.

A piezoelectric micromachined ultrasound transducer (PMUT) device may include a plurality of layers including a structural layer, a piezoelectric layer, and electrode layers located on opposite sides of the piezoelectric layer. Conductive barrier layers may be located between the piezoelectric layer and the electrodes to the prevent diffusion of the piezoelectric layer into the electrode layers.

A vibration generating device 90 includes: a housing 30 in a rectangular shape as viewed in a first direction, the housing 30 comprising: a first support portion 31 extending along a first side in a second direction perpendicular to the first direction and; a second support portion 32 extending along a second side opposite to the first side in the second direction; a panel 60 supported by the first support portion and the second support portion; and a piezoelectric element 11 attached to the panel in such a manner as to be shifted in the second direction toward the first side with respect to a central portion of the panel, wherein a width in the second direction of a portion of the panel supported by the first support portion is larger than a width in the second direction of a portion of the panel supported by the second support portion.

A piezoelectric micromachined ultrasound transducer (PMUT) array may comprise PMUT devices with respective piezoelectric layers and electrode layers. Parasitic capacitance can be reduced when an electrode layer is not shared across PMUT devices but may expose the devices to electromagnetic interference (EMI). A conductive layer located within the structural layer or on a shared plane with the electrode layers may reduce EMI affecting the PMUT array operation.

An ultrasonic sensor includes a vibration plate that includes a vibration portion and is formed of a resin; a wall portion that is provided on the vibration plate, surrounds the vibration portion and is formed of a resin; and a piezoelectric element that is provided in the vibration portion of the vibration plate. Accordingly, the wall portion surrounding the vibration portion can suppress a frequency variation of an ultrasonic wave output from the ultrasonic sensor and can deform the ultrasonic sensor into a shape corresponding to a surface of an object having various shapes.

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 imaging system includes: a transceiver cell for generating a pressure wave and converting an external pressure wave into an electrical signal; and a control unit for controlling an operation of the transceiver cell. The transceiver cell includes: a substrate; at least one membrane suspending from the substrate; and a plurality of transducer elements mounted on the at least one membrane. Each of the plurality of transducer elements has a bottom electrode, a piezoelectric layer on bottom electrode, and at least one top electrode on the piezoelectric layer. Each of the plurality of transducer element generates a bending moment in response to applying an electrical potential across the bottom electrode and the at least one top electrode and develops an electrical charge in response to a bending moment due to the external pressure wave.

The present disclosure provides a method of fabricating an ultrasound transducer. A substrate having a first side and a second side opposite the first side is provided. A bottom electrode is formed over the first side of the substrate. A piezoelectric element is formed over the bottom electrode. The piezoelectric element has a chamfered sidewall. A top electrode is formed over the piezoelectric element. A step metal element is formed over a portion of the top electrode proximate to the chamfered sidewall of the piezoelectric element.

Provided is a video audio system including electroacoustic conversion units which include an electroacoustic conversion film having a macromolecular composite piezoelectric body formed by dispersing piezoelectric body particles in a viscoelastic matrix formed of a macromolecular material that is viscoelastic at normal temperature and thin film electrodes respectively laminated on both surfaces of the macromolecular composite piezoelectric body, curve and support the electroacoustic conversion film, and use at least a part of the electroacoustic conversion film as vibration regions and a display device which is a screen or a video display device to which videos are projected, in which at least one of the electroacoustic conversion units is disposed on a rear surface opposite to a surface of the display device on which videos are displayed, the plurality of vibration regions is arranged on the entire rear surface of the display device, and location information of the vibration regions is included in sound data that are input to the electroacoustic conversion units.

An ultrasonic transducer having a transducer element, a housing, a coupling element with a front and a back, wherein the back of the coupling element is acoustically coupled to the top of the transducer element in order to couple the ultrasonic waves generated by the transducer element out to the environment in a transmit mode or in order to pass the ultrasonic waves received from the environment by the coupling element on to the transducer element in a receive mode. The transducer element and the coupling element are arranged in the housing. A first electrode is connected to a contact area formed on the bottom of the transducer element. The transducer element is arranged in a shielding device made of a metallically conductive material, and the opening of the shielding device is covered by a metallic, conductive screen so that the shielding device and the screen form a Faraday cage.