A piezoelectric device includes a first piezoelectric sensor having a first inner conductor, a first piezoelectric body, and a first outer conductor, a second piezoelectric sensor having a second inner conductor, a second piezoelectric body, and a second outer conductor, and a differential signal forming unit having a pair of differential input terminals. When an external force acts on the first piezoelectric body, the first piezoelectric sensor generates a first voltage, and the second piezoelectric sensor generates a second voltage having a voltage different in polarity from the first voltage. The first inner conductor is electrically connected to one differential input terminal. The second inner conductor is electrically connected to the other differential input terminal. The differential signal forming unit forms a differential signal based on a first signal input to the one differential input terminal and a second signal input to the other differential input terminal.

It is disclosed a composite yarn structure (10) comprising: —a first element (15) comprising a coaxial flexible bi-component monofilament including a conductive component (20) and a thermoplastic component (30) exhibiting piezoelectric properties, —at least a second element (40) twisted around the first element (15), wherein the second element (40) has a lower elasticity with respect to the elasticity of the first element (15) such that, upon elongation of the yarn structure (10) in a first direction, the yarn structure (10) expands in a second direction, whereby the dimensions of the yarn are increased both in first and second directions to generate an additional force on said piezoelectric component of the first element.

Embodiments of the invention include an active fiber with a piezoelectric layer that has a crystallization temperature that is greater than a melt or draw temperature of the fiber and methods of forming such active fibers. According to an embodiment, a first electrode is formed over an outer surface of a fiber. Embodiments may then include depositing a first amorphous piezoelectric layer over the first electrode. Thereafter, the first amorphous piezoelectric layer may be crystallized with a pulsed laser annealing process to form a first crystallized piezoelectric layer. In an embodiment, the pulsed laser annealing process may include exposing the first amorphous piezoelectric layer to radiation from an excimer laser with an energy density between approximately 10 and 100 mJ/cm2 and pulse width between approximately 10 and 50 nanoseconds. Embodiments may also include forming a second electrode over an outer surface of the crystallized piezoelectric layer.

A piezoelectric substrate attachment structure including a cable-shaped piezoelectric substrate, a press section provided adjacent to the piezoelectric substrate and pressed from an opposite side from the piezoelectric substrate, and a base section provided adjacent to the piezoelectric substrate on an opposite side from the press section. A ratio Eb/Ea of a Young's modulus Eb of the base section to a Young's modulus Ea of the press section being 10.sup.−1 or lower.

Provided is a piezoelectric substrate including: an elongate conductor; and an elongate first piezoelectric material helically wound in one direction around the conductor, in which the first piezoelectric material includes an optically active helical chiral polymer (A), the lengthwise direction of the first piezoelectric material and the principal orientation direction of the helical chiral polymer (A) included in the first piezoelectric material are substantially parallel to each other, and the first piezoelectric material has an orientation degree of F. in a range of from 0.5 to less than 1.0, determined from X-ray diffraction measurement by the following Formula (a):
orientation degree F.=(180°−α)/180°  (a) (in Formula (a), α represents a half width of a peak derived from orientation).

Sensing an environment by confining a monitored live subject in an enclosure, detecting an effect on a coaxial piezoelectric cable resulting from the monitored live subject, wherein the coaxial piezoelectric cable is located at least proximate to the enclosure, and deriving information about a state of the monitored live subject based on the detected effect.

A piezoelectric body that is excellent in endurance, flexibility and bendability is achieved. A piezoelectric member includes: belt type first and second conductive rubber sheets that face each other; and a piezoelectric layer formed between an upper surface of the first conductive rubber sheet and a lower surface of the second conductive rubber sheet. The piezoelectric layer is made of a piezoelectric coating material with which at least either one of the upper surface of the first conductive rubber sheet and the lower surface of the second conductive rubber sheet is coated. When a pressure is applied to the piezoelectric layer through at least either one of the first conductive rubber sheet and the second conductive rubber sheet, a potential difference is generated between the first conductive rubber sheet and the second conductive rubber sheet.

Provided is a configuration capable of improving the signal strength of a piezoelectric element using piezoelectric fibers. This braided piezoelectric element comprises a core comprising conductive fibers and a sheath comprising braided piezoelectric fibers so as to cover the core, the braided piezoelectric element further comprising a metal terminal connected and fixed to the core in either of the following states A or B. A) A state where a portion of the metal terminal grasps a fiber portion constituting the end of a braided piezoelectric element and the core and the metal terminal are electrically connected to each other and fixed within 1 mm from where the metal terminal grasps the fiber portion. B) A state where: a portion of the metal terminal has a fork or needle shape; the fork-shaped or needle-shaped portion is electrically connected to the core while in contact with the sheath; and the braided piezoelectric element is secured to the metal terminal by another portion of the metal terminal or a component fixed to the metal terminal within 10 mm from the point of the electrical connection.

Provided is a piezoelectric substrate, containing an elongate piezoelectric body that is helically wound, in which the piezoelectric body includes an optically active polypeptide, a length direction of the piezoelectric body and a main orientation direction of the optically active polypeptide included in the piezoelectric body are substantially parallel to each other, and the piezoelectric body has a degree of orientation F of from 0.50 to less than 1.00, as determined from X-ray diffraction measurement by the following Formula (a):
Degree of orientation F=(180°−α)/180°  (a) in Formula (a), α represents a half width (°) of a peak derived from orientation.

Sensing an environment by confining a monitored live subject in an enclosure, detecting an effect on a coaxial piezoelectric cable resulting from the monitored live subject, wherein the coaxial piezoelectric cable is located at least proximate to the enclosure, and deriving information about a state of the monitored live subject based on the detected effect.