An elastic wave device includes a piezoelectric substrate, an IDT electrode including a first electrode layer located on the piezoelectric substrate and including one of Mo and W as a main component and a second electrode layer laminated on the first electrode layer and including Cu as a main component, and a dielectric film located on the piezoelectric substrate and covering the IDT electrode. The piezoelectric substrate is made of lithium niobate. The dielectric film is made of silicon oxide. The elastic wave device utilizes Rayleigh waves propagating along the piezoelectric substrate.

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.

Methods, systems, and apparatus for using a two-dimensional distributed mode actuator. One of the systems includes a transducer adapted to create a force to cause vibration of a load to generate sound waves, the transducer having a first width along a first axis; a transfer portion connected to the transducer along a first side parallel to the first axis, and having a second width along the first axis that is less than the first width; and a stub connected to the transfer portion along a second side of the transfer portion that is parallel to the first axis and an opposite side from the first side connected to the transducer, having a third width that is greater than the second width, and having a surface adapted to connect to the load to transfer the force received from the transducer through the transfer portion to the load.

Energy harvesting device comprising: a first layer (1) of electrically conductive textile fabric material; a second layer (2) of electrically conductive textile fabric material; a layer of piezoelectric polymer film (3) arranged between the first (1) and the second (2) electrically conductive textile layers; wherein the piezoelectric polymer film layer (3) is laminated between the first (1) and second (2) electrically conductive textile layer.

A form birefringent optical element includes a structured layer and a dielectric environment disposed over the structured layer. At least one of the structured layer and the dielectric environment includes a nanovoided polymer, the nanovoided polymer having a first refractive index in an unactuated state and a second refractive index different than the first refractive index in an actuated state. Actuation of the nanovoided polymer can be used to reversibly control the form birefringence of the optical element. Various other apparatuses, systems, materials, and methods are also disclosed.

Provided is a piezoelectric color filter, wherein the piezoelectric color filter has piezoelectricity and comprises a photoluminescent material. The piezoelectric color filter may have a matrix of a first piezoelectric material being transparent or translucent; and quantum dots distributed in the matrix of the first piezoelectric material. Also provided are a piezoelectric color filter substrate, a display device, and a production method of the piezoelectric color filter.

In some embodiments, the present invention is directed to an exemplary inventive method having steps of: providing at least one housing having a pre-determined physical structure; fixing a first edge of at least one electro-active polymer (EAP) film within the at least one housing; connecting a first edge of at least one pulling mechanism to a second edge of the at least one EAP film; where a second edge of the at least one pulling mechanism extends outside of the at least one housing; sufficiently pulling at the second edge of the at least one pulling mechanism to form at least one pre-stretched EAP film that has been stretched in a first axial direction within the at least one housing by a first pre-determined, pre-stretched amount; and where the pre-determined, pre-stretched amount is limited by the pre-determined physical structure of the housing.

High frequency ultrasound transducers configured for use with high frequency ultrasound diagnostic imaging systems are disclosed herein. In one embodiment, an ultrasound transducer includes a concave lens having an average thickness in a center portion that that is substantially equal to an odd multiple a ¼-wavelength of the center frequency of the ultrasound transducer.

A method for adjusting the stress state of a piezoelectric film having a first stress state at room temperature includes a step of forming an assembly including a carrier having a thermal expansion coefficient, a compliant layer placed on the carrier, and the piezoelectric film placed on the compliant layer, the piezoelectric film having a thermal expansion coefficient different from that of the carrier. The method also includes a step of heat treating the assembly, in which the assembly is heated to a treatment temperature above the glass transition temperature of the compliant layer. The present disclosure also relates to a process for fabricating an acoustic wave device comprising the piezoelectric layer the stress state of which was adjusted as described herein.

In some embodiments, the present invention is directed to an actuator which includes at least the following: a pre-stretched electro-active polymer film being pre-stretched in a single or biaxial planar directions; at least one first semi-stiff conductor attached to a first surface of the pre-stretched electro-active polymer film, wherein the first surface is parallel to the single or biaxial planar stretch directions; at least one second semi-stiff conductor attached to a second surface of the pre-stretched electro-active polymer film, wherein the second surface is opposite to the first surface; where the semi-stiff conductors are configured to: fix the pre-stretched electro-active polymer film in a pre-stretched state and allow the pre-stretched electro-active polymer film to expand; a pair of mechanical connectors coupled to each end of an active region of the pre-stretched electro-active polymer film.