A piezoelectric actuator includes: a plurality of discrete electrodes, which is disposed on one side of a piezoelectric element; a common electrode, which is disposed on the other side of the piezoelectric element; a plurality of discrete contacts, which are respectively connected to the plurality of discrete electrodes, and wherein the plurality of discrete electrodes include: a first discrete electrode; and a second discrete electrode, which is disposed at a position away from a corresponding discrete contact as compared with the first discrete electrode, wherein the common electrode includes: a first common electrode, which faces the first discrete electrode in the thickness direction; and a second common electrode, which is separated from the first common electrode in the surface direction and faces the second discrete electrode in the thickness direction, and wherein a connection wiring is provided to connect the first common electrode with the second common electrode.

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.

An ultrasonic sensor includes a substrate. A first electrode and a first piezoelectric layer are stacked on one side of the substrate. A second electrode and a second piezoelectric layer are stacked on the other side of the substrate. A notch is defined in the first piezoelectric layer. And a conductive film is coated within the notch to couple the first electrode and the first piezoelectric layer.

A vibration wave motor includes a driven body, a vibrator including an annular vibration plate and an annular piezoelectric element, and a vibration damping member, which are arranged in sequence, wherein the vibration plate has, on a side facing the driven body, radially extending groove portions at X places, and, when center depths of the groove portions at X places are sequentially denoted by D1 to DX in a circumferential direction, D1 to DX vary along a curve obtained by superposing one or more sine waves, and wherein the vibration plate is locally supported by the vibration damping member in some or all antinode portions of a standing wave occurring when the vibration wave motor is driven.

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 method for manufacturing a package structure carries out in following way. A flexible circuit board is provided. The flexible circuit board defines a bent area and a laminated area. The flexible circuit board includes a first dielectric layer, a first conductive pattern and a bearing layer located at opposite sides. The bearing layer corresponds to the laminated area. A second dielectric layer and a second conductive pattern are formed on the first conductive pattern. A third dielectric layer and a third conductive pattern are formed on the bearing layer. All of the second and third dielectric layers, and the second and third conductive pattern corresponds to the laminated area. A first solder resist layer is formed on the second conductive layer. The first solder resist layer defines a plurality of openings, a portion of the second conductive pattern is exposed from the openings defining a plurality of first pads.

A microactuator for a dual stage actuated suspension for a hard disk drive is constructed as a longitudinal stack of piezoelectric (PZT) elements acting in the d33 mode, expanding or contracting longitudinally when an electric field is applied across them in the longitudinal direction. The microactuator has interlaced electrode fingers that separate and define the individual PZT elements, and apply the electric field. A stiff constraint layer having a high Young's modulus is affixed to the microactuator on the side opposite the suspension to which the microactuator is bonded. The constraint layer may be a layer of substantially inactive PZT material that is formed integrally with the PZT elements but without electrodes in the inactive PZT layer. The presence of the stiff constraint layer increases the effective stroke length of the microactuator.

The present invention relates to a stacked piezoelectric ceramic element and can provide a stacked piezoelectric ceramic element produced by stacking two or more ceramic green sheets, the stacked piezoelectric ceramic element having a structure in which a ceramic porous or defective part constituting the stacked piezoelectric ceramic element is impregnated with an organic resin, thereby improving waterproof performance capable of preventing the deterioration of insulation resistance in a highly humid environment.

A lead-out wiring, which is connected to a comb-shaped electrode formed on a principal surface of a piezoelectric substrate and is disposed to extend to an outer edge of the piezoelectric substrate an outer surrounding wall layer, which is arranged surrounding an outer periphery of the piezoelectric substrate including the lead-out wiring and forms a hollow portion that serves as an operation space for the comb-shaped electrode, and a top board, which bridges the outer surrounding wall layer to seal the hollow portion, are included.

A piezoelectric ceramic sputtering target containing a perovskite type oxide represented by chemical formula (I) of ABO.sub.3 as a main component, wherein the component A of the chemical formula (I) contains at least K (potassium) and/or Na (sodium), the component B of the chemical formula (I) contains at least Nb (niobium), the piezoelectric ceramic sputtering target is composed of a plurality of crystal grains; and the average particle diameter of the crystal grains is larger than 3 μm and not larger than 30 μm.