An apparatus 10 for poling piezoelectric material includes a platen 22 which holds a sample 20 of piezoelectric material to be poled and a stage 30 to which the platen is mounted. The stage 30 is arranged to selectively move the platen 22 and thereby the sample 20 which the platen 22 holds. The platen 22 is movable by the stage 30 selectively between a first position and a second position. A corona source 40 generates a corona to which the sample 20 is exposed when the platen 22 is moved to the first position by the stage 30. An electrostatic voltmeter 60 having a probe 62 measures a surface potential of the sample 20 when the platen 22 is moved to the second position by the stage 30.

An apparatus 10 for poling piezoelectric material includes a platen 22 which holds a sample 20 of piezoelectric material to be poled and a stage 30 to which the platen is mounted. The stage 30 is arranged to selectively move the platen 22 and thereby the sample 20 which the platen 22 holds. The platen 22 is movable by the stage 30 selectively between a first position and a second position. A corona source 40 generates a corona to which the sample 20 is exposed when the platen 22 is moved to the first position by the stage 30. An electrostatic voltmeter 60 having a probe 62 measures a surface potential of the sample 20 when the platen 22 is moved to the second position by the stage 30.

There is provided a DSR speaker comprising at least a central moving element, a plurality of peripheral flexure benders, each flexure bender comprising at least a pair of electrodes and at least a piezoelectric material layer, the flexure benders being connected to said moving element and being configured to move said moving element along an axis perpendicular to a moving element surface, in response to an electrical stimulus applied to said electrodes, in order to produce sound, and at least a mechanical stopper which is configured to limit the motion of said moving element. Various manufacturing methods are also described.

A process for fabricating a substrate for a radiofrequency device includes providing a piezoelectric substrate and a carrier substrate, depositing a dielectric layer on a surface of the piezoelectric substrate, assembling together the piezoelectric substrate and the carrier substrate with a polymerizable adhesive directly between the dielectric layer and the carrier substrate to form an assembled substrate, and polymerizing the polymerizable adhesive layer to form a polymerized layer bonding the piezoelectric substrate to the carrier substrate, the polymerized layer and the dielectric layer together forming an electrically insulating layer between the piezoelectric substrate and the carrier substrate,

A process for fabricating a substrate for a radiofrequency device includes providing a piezoelectric substrate and a carrier substrate, depositing a dielectric layer on a surface of the piezoelectric substrate, assembling together the piezoelectric substrate and the carrier substrate with a polymerizable adhesive directly between the dielectric layer and the carrier substrate to form an assembled substrate, and polymerizing the polymerizable adhesive layer to form a polymerized layer bonding the piezoelectric substrate to the carrier substrate, the polymerized layer and the dielectric layer together forming an electrically insulating layer between the piezoelectric substrate and the carrier substrate,

The present invention provides: a piezoelectric substrate which includes a first piezoelectric body having an elongated shape and helically wound in one direction, and which does not include a core material, in which the first piezoelectric body includes a helical chiral polymer (A) having an optical activity; in which the length direction of the first piezoelectric body is substantially parallel to the main direction of orientation of the helical chiral polymer (A) included in the first piezoelectric body; and in which the first piezoelectric body has a degree of orientation F, as measured by X-ray diffraction according to the following Equation (a), within the range of 0.5 or more but less than 1.0:

degree of orientation F=(180)/180(a)

(in which represents the half-value width of the peak derived from the orientation).

A micro-electrical-mechanical system (MEMS) guided wave device includes a single crystal piezoelectric layer and at least one guided wave confinement structure configured to confine a laterally excited wave in the single crystal piezoelectric layer. A bonded interface is provided between the single crystal piezoelectric layer and at least one underlying layer. A multi-frequency device includes first and second groups of electrodes arranged on or in different thickness regions of a single crystal piezoelectric layer, with at least one guided wave confinement structure. Segments of a segmented piezoelectric layer and a segmented layer of electrodes are substantially registered in a device including at least one guided wave confinement structure.

A micro-electrical-mechanical system (MEMS) guided wave device includes a single crystal piezoelectric layer and at least one guided wave confinement structure configured to confine a laterally excited wave in the single crystal piezoelectric layer. A bonded interface is provided between the single crystal piezoelectric layer and at least one underlying layer. A multi-frequency device includes first and second groups of electrodes arranged on or in different thickness regions of a single crystal piezoelectric layer, with at least one guided wave confinement structure. Segments of a segmented piezoelectric layer and a segmented layer of electrodes are substantially registered in a device including at least one guided wave confinement structure.

A micro-electrical-mechanical system (MEMS) guided wave device includes a piezoelectric layer including multiple thinned regions of different thicknesses each bounding in part a different recess, different groups of electrodes on or adjacent to different thinned regions and arranged for transduction of lateral acoustic waves of different wavelengths in the different thinned regions, and at least one bonded interface between the piezoelectric layer and a substrate. Optionally, a buffer layer may be intermediately bonded between the piezoelectric layer and the substrate. Methods of producing such devices include locally thinning a piezoelectric layer to define multiple recesses, bonding the piezoelectric layer on or over a substrate layer to cause the recesses to be bounded in part by either the substrate or an optional buffer layer, and defining multiple groups of electrodes on or over the different thinned regions.

A manufacturing a process is provided for the bulk manufacture of transducer arrays, including arrays having at least one 3D printed (or otherwise additive manufactured) acoustic matching layers. In certain implementations, the manufactured transducers include a composite-piezoelectric transducer on a de-matching layer. In one implementation, by producing multiple arrays at once on a common carrier, and by using direct-deposit additive processes for the matching layers, the described processes greatly reduce the number of parts and the number of manual operations.