Abstract: The invention is a device for measuring the temperature of the vibrating beam of a vibrating-beam sensor. It comprises a resonator (10) vibrating in torsion in resonant mode and exhibiting a torsional vibration node (N), said node being its zone of fixing in the vicinity of the middle of the length (L3) of the vibrating beam, said fixing allowing thermal transfers between the resonator and the beam. The frequency of the resonator and the variations of this frequency are representative respectively of the mean temperature T of the beam and of the variations of this temperature T, the effects of which may be compensated by a model.

Abstract: A tuning fork-type vibrator element as a vibrating element includes a drive vibrating arm that performs a flexural vibration, and a drive electrode (a first drive electrode and a second drive electrode) provided on the drive vibrating arm. When a direction in which the drive vibrating arm extends is a Y-axis, a direction in which the drive vibrating arm performs a primary vibration is an X-axis, and a direction orthogonal to the Y-axis and the X-axis is a Z-axis, the drive vibrating arm performs the flexural vibration with a displacement ratio of greater than 0% and 20% or less where the displacement ratio is obtained by dividing a displacement amount in the Z-axis direction by a displacement amount in the X-axis direction.

Abstract: A piezoelectronic transistor device includes a first piezoelectric (PE) layer, a second PE layer, and a piezoresistive (PR) layer arranged in a stacked configuration, wherein an electrical resistance of the PR layer is dependent upon an applied voltage across the first and second PE layers by an applied pressure to the PR layer by the first and second PE layers. A piezoelectronic logic device includes a first and second piezoelectric transistor (PET), wherein the first and second PE layers of the first PET have a smaller cross sectional area than those of the second PET, such that a voltage drop across the PE layers of the first PET creates a first pressure in the PR layer of the first PET that is smaller than a second pressure in the PR layer of the second PET created by the same voltage drop across the PE layers of the second PET.

Abstract: An apparatus for energy conversion, comprising a piezoelectric component comprising a first part configured to convert vibrational energy into electrical energy; and an output for sending a first portion of the generated electrical energy to an electronic device, and a feedback loop for feeding a second portion of the generated electrical energy to a second part of the piezoelectric component, wherein the second part of the piezoelectric component is coupled to the first part of the piezoelectric component and is configured to convert electrical energy into vibrational energy thereby causing the first part of the piezoelectric component to vibrate.

Abstract: The current sensing circuit includes a first input terminal and a second input terminal for introducing a subject current that flows in a current path; a shunt resistor coupled in the current path for converting the subject current into an output voltage difference across the shunt resistor; an amplifier having a first input node coupled to the first input terminal, a second input node coupled to the second input terminal, an output node, and a feedback path including an over-current protection device, wherein the feedback path is coupled between the output node and the first input terminal; and an output terminal coupled to the second input terminal and the shunt resistor to output the output voltage difference. The current sensing circuit has a relatively large current measuring range and a small burden voltage. A measurement device is also described.

Abstract: A finger detection device and method of a fingerprint recognition IC is disclosed. The device comprises sensing electrodes, a capacitive sensing layer, a signal processing circuit, a multiplexer module and a signal register. The sensing electrodes are defined as a fingerprint sensing zone. The capacitive sensing layer covers the sensing electrodes. The signal processing circuit is arranged below and electrically connected with the sensing electrodes. The multiplexer module defines a finger detection zone. The finger detection zone includes at least one of the sensing electrodes. The signal register is electrically connected with the signal processing circuit, receiving a detection signal generated by the finger detection zone and comparing the detection signal with a preset value. The finger detection device uses only a portion of the sensing electrodes to detect a finger approaching/contacting it to determine triggering or sleeping of the fingerprint recognition IC and thus reduces power consumption.

Abstract: A standby power shutoff device is provided that includes a switch generating power when turning on and generating an “on” signal using the power, a switching unit generating an “on/off” signal for a product, a power supply unit providing power for function units of the product by receiving an external input power, a power switching unit driven in response to a driving signal to cut off or connect a power supply path for the input power provided to the power supply unit, a control unit generating a control signal for powering off the product in response to an “off” signal from the switching unit, and a driving unit receiving power from the “on” signal from the switching unit, driving the power switching unit to connect the power supply path, and driving the power switching unit to cut off the power supply path in response to a “power off” control signal.

Abstract: A mobile device configured to authenticate a user, an authentication system, and method for use of the mobile device and authentication system are described that include a biometric sensor, a touchscreen sensor, and/or a fingerprint sensor, where the biometric sensor, the touchscreen sensor, and/or the fingerprint sensor are coupled to a controller configured to authenticate a computing device user. In implementations, the mobile device that employs example techniques in accordance with the present disclosure includes an authentication device, including a biometric sensor configured to receive biometric information from the user; and a fingerprint sensor configured to receive fingerprint information from the user; and a controller configured to authenticate the user, where the authentication device, including the biometric sensor and the fingerprint sensor, is coupled to the controller.

Abstract: Piezoelectric harvesting devices are disclosed herein. An embodiment of a harvesting device includes a cantilever having a resonant frequency associated therewith, wherein the cantilever vibrates when in the presence of a vibration source, and wherein the harvesting device generates a current upon vibration of the cantilever. The generated current is present at an output. A bias flip circuit is used to tune the resonant frequency of the harvesting device based on measurements of the vibration source that causes the cantilever to vibrate, wherein the bias flip circuit includes a switch that connects and disconnects an inductor to the output.

Abstract: A mixing inlay (102) is provided which includes a first radiating element (110a), a second radiating element (110b), and a non-linear mixing component (112) connected between adjacent end portions (114a, 114b) of the first and second radiating elements. The mixing inlay is configured to receive a first exciter signal having a first frequency and a second exciter signal having a second frequency, and in response, to radiate a mixing product signal produced by the mixing inlay from the first and second exciter signals. A conductive parasitic element (116) is disposed within a near field of the re-radiating transponder. A distance provided between the conductive parasitic element and the radiating elements is varied over the length of the conductive parasitic element to enhance a sideband signal generated by the mixing inlay.

Abstract: The systems and methods described herein generally relate to increasing user productivity in reviewing query results by visually depicting the presence/absence of a set of query terms in a set of paragraphs across a set of documents.

Abstract: A zero-voltage-switching (ZVS) piezoelectric driving circuit, suitable for use in a switching type power converter. It receives an input DC voltage from a half-bridge driving circuit, and through switching of an high-side switch set and a low-side switch set of the half-bridge driving circuit, converts it to an AC voltage and provides it to a piezoelectric element to drive a load. Wherein, a shunt circuit is connected electrically between the half-bridge driving circuit and the piezoelectric element for zero-voltage-switching (ZVS). Namely, when the high-side switch set and the low-side switch set are both switched off, the shunt circuit resonates with its parasitic capacitance, so that the high-side switch set and the low-side switch set perform ZVS, thus realizing ZVS in a wide range of frequency and a large range of load.

Abstract: An electronic oscillator circuit has a first oscillator, for supplying a first oscillation signal, a second oscillator, for supplying a second oscillation signal, a first controller for delivering the first control signal as a function of a phase difference between a first controller input and a second controller input of the first controller; a second controller for delivering the second control signal as a function of a phase difference between a first controller input of the second controller and a second controller input of the second controller; a resonator; at least a second resonance frequency, with a first phase shift dependent on the difference between the frequency of a second exciting signal and the second resonance frequency and processing means, for receiving the first oscillator signal and the second oscillator signal, determining their mutual proportion, looking up a frequency compensation factor in a prestored table and outputting a compensated oscillation signal.

Abstract: A high voltage power source device includes piezoelectric transformers, each of the piezoelectric transformers being formed with a primary electrode and a secondary electrode on piezoelectric ceramics, receiving a primary voltage at the primary electrode, and generating a second voltage from the secondary electrode, switching elements, each of the switching elements driving a respective one of the piezoelectric transformers, and primary voltage supply devices, each of the primary voltage supply devices supplying the primary voltage to the primary electrode of the respective one of the piezoelectric transformers by driving the respective one of the switching elements when the secondary voltage is generated from the respective one of the second electrodes, wherein the respective one of the primary voltage supply devices supplies the primary voltage to the respective one of the primary electrodes by driving the respective one of the switching elements at the same frequency.

Abstract: A resonator element includes a vibrating portion that vibrates in a thickness shear vibration and includes a first main surface and a second main surface which are in a front and back relationship to each other, a first excitation electrode that is provided on the first main surface, and a second excitation electrode that is provided on the second main surface, and an energy trapping coefficient M satisfies a relationship of 33.6?M?65.1.

Abstract: Methods, systems, and devices for providing cooling for a mobile device using piezoelectric active cooling devices. Some embodiments utilize piezoelectric actuators that oscillate a planar element within an air channel to fan air within or at an outlet of the air channel. The air channel may be defined by at least one heat dissipation surface in thermal contact with components of the mobile device that generate excess waste heat. For example, the air channel may include a surface that is in thermal contact with a processor of the mobile computing device. In embodiments, the piezoelectric active cooling device may be used in an air gap between stacked packages in a package on package (PoP) processor package. The described embodiments provide active cooling using low power, can be controlled to provide variable cooling, use highly reliable elements, and can be implemented at low cost.

Abstract: A capacitive actuator is connected to an output of an apparatus which is formed with a capacitor connected between an input and a reference potential, with a full bridge with four power switching elements connected in parallel with the capacitor. To charge the capacitive actuator, a control circuit first turns on the first and third power switching elements. Current then flows from the first capacitor via a coil connected between the bridge paths and energy is stored in the coil. When a maximum current value is reached, the first and third power switching elements are switched off and magnetic energy stored in the coil decays due to current flow via the diodes of the second and fourth power switching elements. This charges the capacitive actuator. The capacitive actuator is charged to a predefined voltage by possible repeated switching of the first and third power switching elements.

Abstract: A power generation unit includes a first piezoelectric device having a pair of electrodes, a second piezoelectric device stacked on the first piezoelectric device, a switch electrically connected between the pair of electrodes, a current detection section adapted to detect a current generated in the second piezoelectric device, and a control section adapted to control the switch, and the control section electrically connects the switch for a predetermined period in at least either one of a case in which the current detected by the current detection section reaches a level one of equal to and higher than a first reference value or a case in which the current reaches a level one of equal to and lower than a second reference value.

Abstract: The invention relates to a device for changing the operational state of an apparatus, in particular from a stand-by or power down mode into an active state, which, in order to reduce power consumption during a stand-by mode and, furthermore, in order to reduce accidental powering up of the apparatus, comprises at least one means for transforming a mechanical excitation, in particular applied to the surface of the apparatus, into an electric signal and a power providing means for supplying at least a part of, in particular all, the electric power necessary to enable a change of the operational state of the apparatus wherein the electric power is obtained out of the electric signal. The invention, furthermore, relates to any apparatus comprising this device for changing operational state and a corresponding method.

Abstract: The invention relates to a method for obtaining electrical energy from the kinetic energy waves. According to said method, a device is provided in the water, comprising an electroactive polymer that can expand with the action of the waves. When the electroactive polymer expands, an electrical charge is applied at a specific time for a specific time interval. Said electrical charge is removed during the relaxation of the polymer, except for a residual charge. According to said method, the variables of the electrical target charge required for the operation of the method, and the time intervals for the beginning and end of the charging and discharging of the electroactive polymer are determined. The invention also relates to a system for obtaining electrical energy and to a computer program product comprising commands that can be implemented by a microprocessor for carrying out the calculations in the method according to the invention.

Abstract: An apparatus for energy conversion, comprising a piezoelectric component comprising a first part configured to convert vibrational energy into electrical energy; and an output for sending a first portion of the generated electrical energy to an electronic device, and a feedback loop for feeding a second portion of the generated electrical energy to a second part of the piezoelectric component, wherein the second part of the piezoelectric component is coupled to the first part of the piezoelectric component and is configured to convert electrical energy into vibrational energy thereby causing the first part of the piezoelectric component to vibrate.

Abstract: In the case of a method for operating a piezoceramic sensor with an evaluation electrode, an electrical signal generated by the piezoceramic sensor at the evaluation electrode is evaluated to determine an actuating state of the piezoceramic sensor. The evaluation electrode is subjected to a predetermined reference potential during recurring time intervals, in order to reference the evaluation electrode with the reference potential during these time intervals.

Abstract: A piezoelectric sensor device includes a piezoelectric element, a signal processing unit, a polarization processing unit and a connection switching unit. The piezoelectric element has a piezoelectric body and a pair of electrodes sandwiching the piezoelectric body. The signal processing unit is configured to execute at least one of signal input from the piezoelectric element, and signal output to the piezoelectric element. The polarization processing unit is configured to execute polarization processing in which polarization voltage is applied to the piezoelectric element. The connection switching unit is configured to switch between a first connection state with which the electrodes and the signal processing unit are connected, and a second connection state with which the electrodes and the polarization processing unit are connected.

Abstract: An autonomous, self-powered device includes a radioisotope-powered current impulse generator including a spring assembly comprising a cantilever, and a piezoelectric-surface acoustic wave (P-SAW) structure connected in parallel to the current impulse generator. Positive charges are accumulated on an electrically isolated 63Ni thin film due to the continuous emission of ?-particles (electrons), which are collected on the cantilever. The accumulated charge eventually pulls the cantilever into the radioisotope thin-film until electrical discharge occurs. The electrical discharge generates a transient magnetic and electrical field that can excite the RF modes of a cavity in which the electrical discharge occurs. A piezoelectric-SAW resonator is connected to the discharge assembly to control the RF frequency output.

Abstract: An piezoelectric electromechanical transistor has first and second terminals formed in a semiconductor region, a gate and a piezoelectric region between the gate and the semiconductor region. The piezoelectric region may be configured to drive the semiconductor region to vibrate in response to a signal applied to the gate. The transistor may be configured to produce a signal at the first terminal at least partially based on vibration of the semiconductor region.

Abstract: A resonator includes a resonator element, which includes a quartz crystal substrate formed of crystal, and a package in which the resonator element is housed. The quartz crystal substrate includes a base portion and two vibrating arms that are aligned in the X-axis direction of the crystal and extend from the base portion in the +Y?-axis direction (or the ?Y?-axis direction) of the quartz crystal. The principal surface of the base portion on the ?Z?-axis side (+Z?-axis side when the vibrating arms extend in the ?Y?-axis direction) in the quartz crystal is fixed to the package.

Abstract: A step-down circuit using a piezoelectric transformer that includes a rectangular parallelepiped piezoelectric plate having opposite end portions in a lengthwise direction thereof, which are constituted as two lower voltage portions provided with output electrodes, and a region sandwiched between the two lower voltage portions. The region being partly constituted as a higher voltage portion provided with an input electrode. The two lower voltage portions and the higher voltage portion are each polarized and driven in a 3/2? or a 5/2? mode. The higher voltage portion or vicinities thereof are polarized in directions symmetric to each other on both the sides of a center of the higher voltage portion or on both the sides of the higher voltage portion. The output electrodes on the positive and negative charge sides of respective polarized lower voltage portions are connected to each other.

Abstract: A piezoelectric transformer includes a rectangular plate-shaped piezoelectric board having a length L in a longitudinal direction. In the piezoelectric board, five regions having a length L/5 are formed. In the two of regions, inner electrodes are formed in a thickness direction and conducted to outer electrodes provided in these regions. In a third region, outer electrodes are provided. The two regions of the piezoelectric board are polarized in the thickness direction, and two adjacent regions thereof are polarized in the longitudinal direction, and the third region is non-polarized. When a voltage is applied to the outer electrodes, the piezoelectric board expands and contracts in the longitudinal direction due to a piezoelectric effect. Thus, a piezoelectric transformer which enables high-efficient energy conversion even when a driving frequency is increased and a wireless power transmission system using the piezoelectric transformer are provided.

Abstract: An intrinsic piezoelectric transformer circuit a piezoelectric transformer circuit is provided that has a primary side component including first and second electrodes, a secondary side component including first and second electrodes, and at least one tertiary component including first and second electrodes. A power bridge is provided which includes one or more switches, each switch has a gate terminal that is directly connected to the second electrode of the tertiary component of the piezoelectric transformer. The first electrode of the tertiary component of the piezoelectric transformer is connected to a reference for the one or more switches of the power bridge. The first electrode of the primary component of the piezoelectric transformer is electrically connected to a power bridge output and the second electrode of the primary component of the piezoelectric transformer is connected to a ground terminal.

Abstract: Apparatus and method that includes providing a variable-parameter electrical component in a high-field environment and based on an electrical signal, automatically moving a movable portion of the electrical component in relation to another portion of the electrical component to vary at least one of its parameters. In some embodiments, the moving uses a mechanical movement device (e.g., a linear positioner, rotary motor, or pump). In some embodiments of the method, the electrical component has a variable inductance, capacitance, and/or resistance. Some embodiments include using a computer that controls the moving of the movable portion of the electrical component in order to vary an electrical parameter of the electrical component. Some embodiments include using a feedback signal to provide feedback control in order to adjust and/or maintain the electrical parameter.

Abstract: An apparatus for reducing energy consumption in monitoring means of a plurality of piezoelectric components comprises a plurality of piezoelectric components as well as monitoring means for monitoring the status of the piezoelectric components. The monitoring means have two states namely active and inactive. The piezoelectric components are connected in parallel to each other. A current detecting circuit comprises a switch and a resistor that is connected in parallel to the switch. A controller having two states that are active and inactive. The controller is configured to open the switch in response to the controller being in the inactive state and to close the switch in response to the controller being in the active state. The closing of the switch triggers a state change in the monitoring means from their inactive state to their active state.

Abstract: In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that comprises a handpiece housing that operably supports an electrical contact assembly therein that is in electrical communication with a signal source. An acoustic assembly is supported within the handpiece housing in rotatable contact with the electrical contact assembly. In various embodiments, the signal source produces at least one of an ultrasonic signal and a radio frequency signal.

Abstract: A piezoelectric device includes an integrated circuit (IC) chip and a piezoelectric resonator element, a part of the piezoelectric resonator element being disposed so as to overlap with a part of the IC chip when viewed in plan. The IC chip includes: an inner pad disposed on an active face and in an area where is overlapped with the piezoelectric resonator when viewed in plan; an insulating layer formed on the active face; a relocation pad disposed on the insulating layer and in an area other than a part where is overlapped with the piezoelectric resonator element, the relocation pad being coupled to an end part of a first wire; and a second wire electrically coupling the inner pad and the relocation pad, the second wire having a relocation wire and a connector that penetrates the insulating layer, the relocation wire being disposed between the insulating layer and the active face.

Abstract: Provided are various embodiments of an adjustment circuit, having a base layer and a piezoelectric layer juxtaposed relative to the base layer and including a first electrode such that when the piezoelectric layer is stressed a polarization charge appears between the base layer and one side of the piezoelectric layer and an opposite polarization charge appears on an opposite side of the piezoelectric layer.

Abstract: The invention relates to a circuit arrangement (20) for a piezo transformer (22) comprising a driver circuit (23), to which the piezo transformer (22) can be connected, and a current sensor (21) for the determining an incoming power signal (IM), which is subject to an incoming current (IE) flowing through the piezo transformer (22). The invention further relates to the circuit arrangement (20) of a control unit (24) for providing a control signal (ST), which is subject the incoming power signal (IM); and an oscillator (25) having an oscillator output (43) for emitting an oscillator signal (SO) to a driver signal input (44) of the driver circuit (23) subject to the control signal (ST).

Abstract: Devices for sensing gradients are constructed from material whose properties change in response to gradients. One embodiment of the device is a transducer (200) for sensing gradients that includes the material (210) and two or more electrodes (240, 270) coupled to the material. In one embodiment, gradients in a surrounding medium (110) modify the energy gap of the material in the transducer (130) producing a diffusion current density (150). The material is configured to connect to a current or voltage measurement device (520, 530, 540) where a measurement is used to determine the gradient in the medium (160). The devices can be used to measure pressure, temperature, and/or other properties. The transducer can be built on the same substrate as complementary circuitry. A transducer made of Indium. Antimonide is used in marine seismology to measure pressure gradients.

Abstract: Techniques herein describe a pumping system, adapted to reduce or eliminate fluid cavitation. Optionally, the pumping system is adapted for application to a passive fluid recovery system. In one example, the pumping system includes a pump and a thermal sub-cooling device. The thermal sub-cooling device may sub-cool fluid input to a pump and heat fluid output from the pump, particularly under start-up conditions. In a further example, a controller manages power supplied to both the pump and the thermal sub-cooling device, to transition from an ambient temperature start-up condition to an elevated temperature operating condition.

Abstract: An oscillating circuit for determining a resonant frequency of an electro-mechanical oscillating device and for driving the electro-mechanical oscillating device at the determined resonant frequency includes a driving circuit and a start-up, impetus injection circuit. The driving circuit is configured to receive one or more reference signals and further configured to provide a driving signal related to the reference signals to the electro-mechanical oscillating device. The start-up, impetus injection circuit is operably coupled to the electro-mechanical oscillating device and configured to selectively provide a start-up excitation signal to the electro-mechanical oscillation device. The start-up, impetus injection circuit is activated upon start-up of the oscillating circuit to drive the electro-mechanical oscillation device and the driving circuit determines a resonant frequency by measuring a parameter related to the resonant frequency of the electro-mechanical oscillating device.

Abstract: There is provided a method for testing a piezoelectric/electrostrictive actuator, wherein the displacement of a piezoelectric/electrostrictive actuator is estimated on the basis of the relations between one or more frequency characteristic values selected from the group consisting of the heights and areas of the peaks of the resonance waveforms and the difference of the maximum and minimum of the first order or first to higher orders of the resonance frequency characteristic values of the piezoelectric/electrostrictive actuator and the k-th order (k=1 to 4) of the first or first to higher orders of resonance frequencies. According to this piezoelectric/electrostrictive actuator testing method, a piezoelectric/electrostrictive actuator can be tested with high precision without actually driving the same as a product and without being accompanied by any disassembly/breakage.

Abstract: A resonator element which can achieve a reduction in size while maintaining vibration characteristics, and a piezoelectric device and an electronic device, are to be provided. A quartz crystal resonator element has a base portion, a pair of arm portions extending from the base portion as a root, and a cut-out portion formed by reducing the width of the base portion in the width direction from each side of the arm portions. The root has a first root portion positioned on a side where the arm portions are opposed to each other, and a second root portion positioned on a side where the arm portions are not opposed to each other, and a relationship between a length A from the first root portion to the second root portion and a length B from the first root portion to an inner end portion of the cut-out portion is A?B.

Abstract: A system for positioning an object, having a fixed base, a support for the object, an actuator for applying a force to displace the support relative to the fixed base, a sensor for measuring the load force on the support, and a controller for processing the measured load force to control the position of the support and/or damp at least one resonance frequency of the system. A method of controlling the system is also provided.

Abstract: A novel Si MEMS piezoresistive resonator is described. The resonator has a shape of a frame, such as a ring or a polygon frame, which has two or more anchors. Electrodes located at the outer or inner rim of the resonant structure are used to excite the structure electrostatically into resonance with a desired mode shape. One or plurality of locally doped regions on the structure is used for piezoresistive readout of the signal. In the most preferred embodiments, the structure is a ring, which has four anchors, two electrodes and four piezoresistive regions at different segments of the structure. The piezoresistive regions are alternatively located at the outer rim and inner rim of the structure in such a way that the piezoresistive signals of the same sign from different regions can be collected. Advantages of this device are large readout signal, large electrode area, robustness, suppressed out-of-plane vibration and larger usable linear range.

Abstract: Microelectromechanical resonators include a resonator body with a built-in piezoelectric-based varactor diode. This built-in varactor diode supports passive frequency tuning by enabling low-power manipulation of the stiffness of a piezoelectric layer, in response to controlling charge build-up therein at resonance. A resonator may include a composite stack of a bottom electrode, a piezoelectric layer on the bottom electrode and at least one top electrode on the piezoelectric layer. The piezoelectric layer includes a built-in varactor diode, which is defined by at least two regions having different concentrations of electrically active dopants therein.

Abstract: In an embodiment, a piezoelectric resonator configured for parametric amplification is disclosed. The piezoelectric resonator may include or comprise a piezoelectric member, and first and second resonator electrodes associated with the piezoelectric member and positioned to enable a first electric field to be generated in a first direction. The piezoelectric resonator may also include or comprise a parametric drive electrode associated with the piezoelectric member and positioned to enable a second electric field to be generated in a second direction.

Abstract: A piezoelectric vibrator is used in an electronic device having a screen. The piezoelectric vibrator includes a diaphragm, at least one piezoelectric layer attached to the diaphragm, and a vibrating element extending from the diaphragm for being coupled to a surface of the screen.

Abstract: The present invention relates to a method of measuring and evaluating rigidity of a target object or mechanical output, such as force, displacement, and mechanical energy generated by a piezoelectric actuator and applied to the target object, according to only a measured value of electric quantity without use of a mechanical sensor, and a method of controlling the piezoelectric actuator, and a device using these methods. Steps of finding equivalent circuit constants of the piezoelectric actuator; applying a voltage to the piezoelectric actuator and measuring electrical quantity flowing into the piezoelectric actuator due to the applied voltage, or applying an electric charge to the piezoelectric actuator and measuring voltage applied to the piezoelectric actuator due to the applied electric charge; and measuring and evaluating one or more of force, displacement, or mechanical energy generated by the piezoelectric actuator and applied to a target object, or rigidity of a target object are included.

Abstract: Provided is a method for determining a resonant frequency of a biometric sensor. The method includes obtaining first pixel data from a first scan by scanning the biometric sensor with a first frequency. Second pixel data is obtained from a second scan by scanning the biometric sensor with a second frequency that is different from the first frequency. A respective first and second reference value is calculated from the first and the second pixel data. A highest reference value is determined from the first and the second reference values. The first or the second frequency is selected as the resonant frequency based on the highest reference value.

Abstract: A control device for suppression of residual vibration of a piezoelectric transducer includes a capacitive energy storage component, and a switch unit. The control device is operable in a non-working mode, in which the switch unit provides voltage on the capacitive energy storage component to the piezoelectric transducer for reducing the residual vibration of the piezoelectric transducer. The capacitive energy storage component has a capacitance value that is sufficient for enabling the voltage on the capacitive energy storage component to substantially track voltage on the piezoelectric transducer under the non-working mode.

Abstract: An image capturing apparatus with an image sensor converting the image of a subject and an optical member in front of the image sensor. First and second piezoelectric elements at respective ends of the optical member are independently driven by respective first and second driving units. A detection unit has first and second detecting piezoelectric elements adjacent to the respective first and second piezoelectric elements for detecting vibration of the optical member. A first control unit controls the first and second driving units and the detection unit to vibrate the optical member by vibrating the first piezoelectric element and detect vibration of the optical member using the second detecting piezoelectric element, or vibrate the optical member by vibrating the second piezoelectric element and detect vibration of the optical member using the first detecting piezoelectric element.

Abstract: An in-plane actuated resonant device, and method of manufacturing the device. The device includes a support; a suspended beam, moving parallel to the plane of the surface of the support and anchored to the support through at least one of its ends; and a mechanism actuating the beam to enable its displacement parallel to the support. The actuation mechanism includes at least one suspended element, anchored to the support and to one lateral face of the beam. The element moves when a control voltage is applied to the element and thus causes displacement of the beam. The device may be manufactured using surface technology and is applicable particularly for resonant mass sensors.