There are provided an ultrasonic transducer and methods for designing and manufacturing the same. The ultrasonic transducer includes a piezoelectric composite layer configured to be in acoustic communication with a sample and having at least partially decoupled acoustic impedance and electrical impedance properties. The piezoelectric composite layer includes an array of spaced-apart piezoelectric regions, each being made from a piezoelectric material, a filler material positioned between adjacent spaced-apart piezoelectric regions, the filler material comprising a polymer matrix and a non-piezoelectric material in contact with the polymer matrix. In some embodiments, the ultrasonic transducer includes an electrically insulating non-piezoelectric composite layer extending over the piezoelectric composite layer for electrically insulating the piezoelectric composite layer from the sample, the electrically insulating non-piezoelectric composite layer being acoustically matched to the piezoelectric composite layer and the sample.

An optoelectronic component includes an optical transducer made of III-V semiconductor material and an optical scanning microelectromechanical system comprising a mirror. The optical transducer and the optical scanning microelectromechanical system are produced on a common wafer comprising at least a first layer made of silicon or silicon nitride with a thickness of less than one micron and wherein at least the mirror and its holding springs are produced. In a first variant, the mobile parts of the optical scanning microelectromechanical system are produced in various layers of silicon. In a second variant, the mobile parts of the optical scanning microelectromechanical system are produced in the layer of III-V semiconductor material.

Provided are a laminated piezoelectric element and an electroacoustic transducer capable of obtaining high piezoelectric characteristics and easily ensuring an electric contact to an electrode layer. A plurality of layers of piezoelectric films, each of which is formed by laminating a first protective layer, a first electrode layer, a piezoelectric layer, a second electrode layer, and a second protective layer in this order, are laminated. Each of the piezoelectric layers is polarized in a thickness direction. In each of the piezoelectric films, the first electrode is disposed on an upstream side in a polarization direction of the piezoelectric layer, and the second electrode is disposed on a downstream side. Each of the plurality of piezoelectric films has a cemented portion which is cemented to an adjacent piezoelectric film and a protruding portion which is not cemented to the adjacent piezoelectric film and in which at least the first electrode layer and the first protective layer or the second electrode layer and the second protective layer protrude from the cemented portion toward the outside in a plane direction. At the protruding portion of each of the piezoelectric films, at least one of a first contact, to which the first electrode layers of the piezoelectric films are electrically connected to each other, or a second contact, to which the second electrode layers of the piezoelectric films are electrically connected to each other, is formed.

A composite fiber composed of at least a metal sintered body and a ceramic sintered body. In the composite fiber, the metal sintered body and the ceramic sintered body are adjacent to each other. The composite fiber having the metal sintered body and the ceramic sintered body can have a tensile strength of 5 kgf/mm.sup.2 or more.

Parts made by additive manufacturing are often structural in nature, rather than having functional properties conveyed by a polymer or other component present therein. Printed parts having piezoelectric properties may be formed using compositions comprising a plurality of piezoelectric particles and a polymer material comprising at least one thermoplastic polymer and at least one thermally curable polymer precursor. At a sufficient temperature, the at least one thermally curable polymer precursor may undergo a reaction, optionally also undergoing a reaction with the piezoelectric particles, and form an at least partially cured printed part. The piezoelectric particles may be mixed with the polymer material and remain substantially non-agglomerated when combined with the polymer material. The compositions may define a form factor such as a composite filament, a composite pellet, or an extrudable composite paste, which may be utilized in forming printed part by extrusion, layer-by-layer deposition, and thermal curing.

A sensor is disclosed which includes a piezoelectric layer, a piezoresistive layer, one or more electrode layers coupled to the piezoelectric layer and to the piezoresistive layer, the piezoelectric layer configured to provide an electrical signal in response to application of a dynamic disturbance, and the piezoresistive layer configured to provide a change in resistivity in response to application of a static disturbance.

The present disclosure provides a flexible electric generator and methods for fabricating the same. The flexible electric generator comprises a flexible triboelectric layer covering the electrode layer of a flexible piezoelectric generator that enhances output power by combining piezoelectric effect and triboelectric effect. The reliability of the flexible electric generator under bending is also improved due to the presence of the flexible triboelectric layer. The fabrication methods of the disclosed flexible electric generators are simple, thereby enabling large-scale manufacturing.

A synchronized piezoelectric and luminescence (SPL) material includes a core layer including light-emitting particles and a shell layer which is attached onto a surface of the core layer and includes ligands having a piezoelectric property. Therefore, a piezoelectric property and a luminescent property can be simultaneously implemented using a single SPL material in which piezoelectric ligands and light-emitting particles are chemically coupled.

A barium titanate fiber is useful as a filler for a polymer composite piezoelectric body, a polymer composite piezoelectric body has high piezoelectric properties, and a piezoelectric element utilizes the polymer composite piezoelectric body. In the barium titanate fiber, the molar ratio of barium atoms to titanium atoms (Ba/Ti ratio) falls within the range of 1.01 to 1.04. The polymer composite piezoelectric body includes a resin composition containing the barium titanate fiber and a polymer. The piezoelectric element including an electrically conductive layer on one surface or both surfaces of the polymer composite piezoelectric body.

Provided are an electroacoustic transduction film capable of reproducing a sound with a sufficient sound volume at a high conversion efficiency, a manufacturing method thereof, an electroacoustic transducer, a flexible display, a vocal cord microphone, and a sensor for a musical instrument. The electroacoustic transduction film includes: a polymer composite piezoelectric body in which piezoelectric body particles are dispersed in a viscoelastic matrix formed of a polymer material having viscoelasticity at a normal temperature; two thin film electrodes laminated on both surfaces of the polymer composite piezoelectric body; and two protective layers respectively laminated on the two thin film electrodes, in which an intensity ratio α.sub.1=(002) plane peak intensity/((002) plane peak intensity+(200) plane peak intensity) between a (002) plane peak intensity and a (200) plane peak intensity derived from the piezoelectric body particles in a case where the polymer composite piezoelectric body is evaluated by an X-ray diffraction method is more than or equal to 0.6 and less than 1.