A sensor device that includes a film composed of, for example, PLLA; and electrodes for extracting an output voltage from the PLLA film. The electrodes are located on main surfaces of the PLLA film such that the electrodes face each other with at least a portion of the PLLA film being interposed therebetween. The PLLA film has a first side which is fixed, and a second side which is opposite to the first side and is a movable portion. Each of the electrodes is configured to extract an output voltage resulting from an effect of piezoelectric constant d.sub.14 provided by shear deformation caused by displacement of the movable portion in a direction parallel to the main surfaces of the PLLA film, whereby an operation involving friction or the like can be sensed.

A transducer device, including an electroactive polymer transducer, which has at least two electrode layers which are situated in parallel to one another and which are connected to one another by inserting an elastic intermediate layer in each case, and including a circuit having electronic components for the purpose of generating an electrical voltage applied to the electrode layers of the polymer transducer, the circuit increasing an input voltage to a voltage which is increased with regard to the input voltage.

An ultrasonic sensor includes a first electrode, a first piezoelectric layer, a substrate, a second electrode, a second piezoelectric layer, and a third electrode. The first electrode and the first piezoelectric layer are stacked on a first surface of the substrate. The second electrode, the second piezoelectric layer, and the third electrode are stacked on a second surface opposite to the first surface of the substrate. The substrate is made of chemically strengthened glass.

The present invention provides electroactive polymer (“EAP”) transducers having improved properties. This improvement is achieved without decreasing film thickness, or by using high dielectric constant and high field, so that this approach does not adversely affect the reliability and physical properties of the resultant dielectric films. Mobile electrically active additives are added to the electrode formulation which significantly improve the performance of electroactive polymer transducers. Such additives do not need to be ionic. These electrically active additives can enable higher performance devices, smaller devices using less active area, lower voltage/power operation, and combinations of these enhancements.

A membrane switch in which a first conductive part is formed on a first substrate, a second conductive part is formed on a second substrate, and the substrates are layered via a spacer such that the conductive parts face each other with a space therebetween, and an organic material showing piezoelectricity is filled, or disposed in the space such that an air gap is present, are useful for obtaining an output signal corresponding to an applied pressure.

A power generator includes layered-polymer piezoelectric element that is arranged on an object to be a heat source and a vibration source, and that generates electric power according to vibration transmitted from the object; a first heat conductor containing a flexible material that is arranged on the object, and that conducts heat from the object. The power generator includes a second heat conductor that is arranged on the first heat conductor and the layered-polymer piezoelectric element, and that conducts heat from the first heat conductor. Furthermore, the power generator includes a thermoelectric element that is arranged on the second heat conductor so as to be layered on the second heat conductor on the layered-polymer piezoelectric element, and that generates electric power according to inner temperature difference between temperature on a heat absorbing side obtained by the second heat conductor and temperature on a heat releasing side.

An electroactive polymer transducer including a dielectric elastomer material having a first configuration with a first spring constant and a second configuration with a second spring constant and where the second spring constant is lower than the first spring constant.

A polymeric piezoelectric material, comprising at least two regions: a region H, which is an oriented polymeric piezoelectric region that includes an optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, the region H having a crystallinity of from 20% to 80% and having a standardized molecular orientation-of from 3.5 to 15.0; and a region L, which is a low orientation region that includes the optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, the region L being present near at least part of an end portion of the region H, having an average width when viewed from a normal direction with respect to the principal plane of the region H of from 10 μm to 300 μm, and having a retardation is 100 nm or less.

A piezoelectric device includes a first region for receiving a pressing operation and a second region located outside of the first region. A piezoelectric element outputs a stronger potential when a pressing operation is applied to the first region than when the pressing operation is applied to the second region.

Provided is a multilayer actuator and a display device comprising the same with improved driving displacement that includes, for example, a plurality of electroactive layers, wherein the electroactive layers comprise a ferroelectric polymer, and polarization directions of all electroactive layers are substantially the same.