A flexoelectricity ultrasonic (UT) transducer imaging system is disclosed comprising a polytetrafluoroethylene (PTFE) layer, a plurality of flexoelectricity UT transducers, and a multiplexer. The PTFE layer includes a front and back surface and the plurality of flexoelectricity UT transducers is attached to the back surface of the PTFE layer. Each UT transducer has a front-end and back-end and the front-end of each flexoelectricity UT transducer is attached to the back surface of the PTFE layer. The flexoelectricity UT transducers are arranged along the back surface of the PTFE layer as a two-dimensional array and each flexoelectricity UT transducer is configured to vibrate in a normal direction to the back surface of the PTFE layer. The multiplexer in signal communication with each flexoelectricity UT transducer, where the flexoelectricity UT transducers are sandwiched between the multiplexer and the PTFE layer.

A flexible piezoelectric thin film, and method of manufacture, has a polyvinyl alcohol (PVA)-glycine-PVA sandwich heterostructure. The thin film is manufactured by evaporating the solvent from a glycine-PVA mixture solution. The film automatically assembles into the PVA-glycine-PVA sandwich heterostructure as it is salted out. Strong hydrogen bonding between the oxygen atoms in glycine and hydroxyl groups on PVA chains are responsible for the nucleation and growth of the piezoelectric γ-glycine and alignment of the domain orientation.

A method for manufacturing an electroactive polymer device which includes a layered structure including a dielectric polymer layer and an electrode layer, wherein the electrode layer is arranged on a surface of the dielectric polymer layer. The method includes: providing the dielectric polymer layer; determining a surface area location of a defect on a first surface of the dielectric polymer layer; creating an electrode layer including an area void of electrode layer material surrounding the surface area location, and the electrode layer includes a patch of electrode material covering the surface area location and a remainder part of the surface of the dielectric polymer layer surrounding the area void of electrode layer material, in which the patch and the remainder part are electrically isolated from one another.

A method for forming a dielectric elastomer transducer of the present invention includes: a first electrode layer fixing step of fixing a first electrode layer to a target object; a dielectric elastomer layer fixing step of fixing a dielectric elastomer layer to the first electrode layer; and a second electrode layer fixing step of fixing a second electrode layer to the dielectric elastomer layer. This configuration ensures that the dielectric elastomer transducer highly conforms to the target object.

An object is to provide a piezoelectric film with good piezoelectricity. This object can be achieved by a piezoelectric film comprising a vinylidene fluoride/tetrafluoroethylene copolymer film and having a residual polarization amount of 40 mC/m.sup.2 or more.

A dielectric elastomer transducer A1 includes a dielectric elastomer layer 2, a pair of electrode layers 3A, 3B sandwiching the dielectric elastomer layer 2, and a support 1 that supports the dielectric elastomer layer 2. The dielectric elastomer layer 2 includes a movable region 21 separated from the support 1 and a fixed region 22 supported by the support 1. A pair of conduction paths 8A, 8B are established that are configured to conduct electricity to the electrode layers 3A, 3B via power cables 4A, 4B and power supply points 6A, 6B at which core wires 41A, 41B of the power cables 4A, 4B are electrically connected, respectively. The power supply points 6A, 6B are separated from the movable region 21 of the dielectric elastomer layer 2. This arrangement improves the durability of the dielectric elastomer transducer.

Methods, systems, and apparatus, including combination therapy systems for the treatment of infections. These systems comprising: an ultrasound device capable of producing ultrasonic acoustic pressure; and a biodegradable piezoelectric film comprising polymer-based piezoelectric material, poly(L-lactic acid) (PLLA) nanofiber mesh configured to, when placed in an electrolytically conductive environment comprising water and stimulated with the ultrasonic acoustic pressure, vibrate generating electricity to locally decomposes the water into reactive oxygen species (ROS) to induce a broad-spectrum bactericidal effect.

A piezoelectric sensor, comprising: a stress applying layer in which a plurality of stress applying grooves extending in parallel with a first direction are formed in a predetermined region on a whole surface; and a piezoelectric layer that is layered on the stress applying layer and formed from a polymer piezoelectric material containing an optical active polymer.

An electroactive polymer actuator includes an electroactive polymer structure and a driver for providing an actuation drive signal. In one aspect, a first drive level is used to charge the electroactive polymer structure from a non-actuated state to an actuated state. When or after the electroactive polymer structure reaches the actuated state, a lower second drive level is used to hold the electroactive polymer structure at the actuated state. This temporary overdrive scheme improves the speed response without damaging the electroactive polymer structure. In another aspect, a driving method makes use of several different level segments over time, which compensates for the delayed actuation response of the EAP actuator.

The present invention provides a composition for forming a polyvinylidene fluoride film, which contains: a polyvinylidene fluoride; at least one surfactant that is selected from among sulfuric acid-based surfactants, sulfonic acid-based surfactants and quaternary ammonium salt type surfactants; and a solvent.