Methods, devices and apparatus for measuring expansion/contraction properties of a material are described. According to an embodiment a method comprises: providing a device, said device comprising a sample comprising said material, said sample comprising a first surface and a second surface, a first substrate and a second substrate connected to said first surface and to said second surface of said sample, respectively, a reflective material attached to said second substrate, and two electrical contacts each independently in contact with said sample; applying voltage to said sample using said electrical contacts; illuminating said reflective material using a light source, such that said illumination comprises light having known and controllable polarization; collecting light reflected off said reflective material; measuring amplitude and phase of an oscillating change in polarization of the reflected light; and extracting parameters related to expansion/contraction from said reflected light measurement, thus evaluating said expansion/contraction properties of said material.

An electronic component includes a first surface with a first electrode and a second surface with a second electrode. A measuring instrument includes a first terminal and a second terminal. Only the second surface out of the first surface and the second surface is adhered to a conductive adhesive sheet. The first terminal of a measuring instrument is electrically connected to the first electrode at the first surface, the second terminal of the measuring instrument is electrically connected to the second electrode through the conductive adhesive sheet at the second surface, and the electronic component is measured using the measuring instrument.

An electronic component includes a first surface with a first electrode and a second surface with a second electrode. A measuring instrument includes a first terminal and a second terminal. Only the second surface out of the first surface and the second surface is adhered to a conductive adhesive sheet. The first terminal of a measuring instrument is electrically connected to the first electrode at the first surface, the second terminal of the measuring instrument is electrically connected to the second electrode through the conductive adhesive sheet at the second surface, and the electronic component is measured using the measuring instrument.

A method estimates a level of damage or a lifetime expectation of a power semiconductor module having at least one die that is mechanically and electrically attached to a ceramic substrate. The ceramic substrate has piezoelectric properties and the method includes: controlling the at least one power die, the control of the at least one power die generating changes in the electrical potential across the ceramic substrate; obtaining information representative of a mechanical deformation of the ceramic substrate; determining if a notification indicating the level of damage or the lifetime expectation has to be performed according to the obtained information and reference information; and notifying the level of damage or the lifetime expectation if the determining step determines that the notification has to be performed.

Provided is a method for inspecting a piezoelectric element in which voltage is applied to a piezoelectric element and evaluation of the electrical characteristics of the piezoelectric element is performed. The method includes a first step in which the piezoelectric element is held on a flat plate-shaped slightly adhesive sheet and a second step in which voltage is applied to the piezoelectric element held on the slightly adhesive sheet and evaluation of the electrical characteristics of the piezoelectric element is performed.

A method for measuring equivalent circuit parameters and resonant frequency of a piezoelectric resonator, by which the phase-frequency curve of the piezoelectric resonator is measured, and the resonant frequency and the anti-resonant frequency are obtained. Then, the slopes of the phase-frequency curve at the resonant frequency and the anti-resonant frequency are respectively measured. The resonant angular frequency and the anti-resonant angular frequency are also calculated. Finally, the equivalent circuit parameters of the piezoelectric resonator are obtained by solving a system of nonlinear equations.

A method for measuring equivalent circuit parameters and resonant frequency of a piezoelectric resonator, by which the phase-frequency curve of the piezoelectric resonator is measured, and the resonant frequency and the anti-resonant frequency are obtained. Then, the slopes of the phase-frequency curve at the resonant frequency and the anti-resonant frequency are respectively measured. The resonant angular frequency and the anti-resonant angular frequency are also calculated. Finally, the equivalent circuit parameters of the piezoelectric resonator are obtained by solving a system of nonlinear equations.

This invention is about a detection device based on the piezoelectric property of geological minerals. The device has a vibration detector for compressing geological minerals to generate charges, so as to detect vibration and a physiotherapy jacket for carrying out quantitative physiotherapy on a human body by detecting the amount of charges. The system has the advantages of: being simple in structure, comprising the vibration detector and the physiotherapy jacket, using the piezoelectric property of geological minerals such as quartz and tourmaline, so as to realize detection of environmental vibration indoors, underground or in the field, and improving the safety factor of geological exploration operations.

Activity of piezoelectric material dimension and electrical properties can be changed with an applied stress. These variations are translated to a change in capacitance of the structure. Use of capacitance-voltage measurements for the extraction of double piezoelectric thin film material deposited at the two faces of a flexible steel sheet is described. Piezoelectric thin film materials are deposited using RF sputtering techniques. Gamry analyzer references 3000 is used to collect the capacitance-voltage measurements from both layers. A developed algorithm extracts directly the piezoelectric coefficients knowing film thickness, applied voltage, and capacitance ratio. The capacitance ratio is the ratio between the capacitances of the film when the applied field in antiparallel and parallel to the polling field direction, respectively. Piezoelectric bulk ceramic is used for calibration and validation by comparing the result with the reported values from literature. Extracted values using the current approach match well values extracted by existing methods.

Systems, methods and piezoelectric patches are provided for monitoring the structural health of connectors in overhead transmission lines. A plurality of piezoelectric patches is mounted to different locations on the connector. At least one of the patches is actuated using an AC voltage and certain electrical properties either from the same patch or of a different patch are evaluated over time to determine the structural health of the connectors.