Abstract: A method of manufacturing a capacitive microphone comprises providing a substrate having at least one cavity. The method further comprises forming a backplate on the substrate, wherein the backplate has a plurality of holes, and forming a diaphragm on the backplate, wherein there are a first distance and a second distance between the diaphragm and the backplate. The method still further comprises forming an air gap between the backplate and the diaphragm through the first distance, and fastening the diaphragm to the backplate through the second distance.

Abstract: A piezoelectric thin film device comprises a piezoelectric thin film having upper and lower surfaces and a defined tilted crystal morphology, a top electrode disposed on the upper surface, a substrate having a surface morphology that corresponds to the defined crystallographically tilted morphology, and a bottom electrode disposed between and crystallographically linked to both the lower surface of the piezoelectric thin film and the substrate surface, the bottom and top electrodes having a parallel planar configuration relative to the plane of the substrate and the defined crystallographically tilted morphology having a crystallographic c-axis direction oriented at a >0° angle relative to the normal to the plane of the electrodes; and method of making the device.

Abstract: A method of protecting a resonating sensor is described. The protected resonating sensor may include at least one passive ultrasonically excitable resonating sensor unit. Each sensor unit has one or more vibratable members having a resonating frequency that varies as a function of a physical variable in a measurement environment. The sensor is protected by forming one or more protective chambers defined between a compliant member and the vibratable member(s). A substantially non-compressible medium is disposed within the protective chamber(s). The compliant member has a first side that may be exposed to a measurement environment and a second side that may be exposed to the substantially non-compressible medium. The substantially non-compressible medium may be a liquid or gel and is in contact with the vibratable member(s). When the medium is a liquid, the chamber is sealed. When the medium is a gel, the chamber may be sealed or non-sealed.

Abstract: An ultrasound transducer includes an array of PZT elements mounted on a non-recessed distal surface of a backing block. Between each element and the backing block is a conductive region formed as a portion of a metallic layer sputtered onto the distal surface. Traces on a longitudinally extending circuit board—preferably, a substantially rigid printed circuit board, which may be embedded within the block—connect the conductive region, and thus the PZT element, with any conventional external ultrasound imaging system. A substantially “T” or “inverted-L” shaped electrode is thereby formed for each element, with no need for soldering. At least one longitudinally extending metallic member mounted on a respective lateral surface of the backing block forms a heat sink and a common electrical ground. A thermally and electrically conductive layer, such as of foil, transfers heat from at least one matching layer mounted on the elements to the metallic member.

Abstract: In an exemplary method for making crystal vibrating devices, four wafers are provided: a crystal wafer, a base wafer, a first-lid wafer, and a second-lid wafer. The crystal wafer defines multiple crystal vibrating pieces including respective frames and respective electrodes formed on both main surfaces thereof. The base wafer defines multiple base plates bondable to one main surface of respective frames. The first-lid wafer defines multiple first lids bondable to the other main surface of the respective frames. Each first lid defines a void registrable with respective electrodes. The second-lid wafer is sized similarly to and bondable to the first-lid wafer so as to sealably close the voids. In a first bonding step the crystal wafer is bonded to the base wafer and first-lid wafer. In a subsequent adjustment step the thickness of at least one electrode per each crystal vibrating piece is adjusted to adjust the vibrational frequency of the respective vibrating portion.

Abstract: The present invention is a piezoelectric crystal oscillator using parametric amplification to enhance the Q. Parametric amplification is accomplished by driving the same region of the crystal as used for the oscillator with an overtone of the crystal resonator.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis, and the dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration, resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration resulting from twisting of the rotation axis match. The vibrator includes a torsional piezoelectric body that generates a thickness shear vibration, and that is arranged at an anti-node position of the torsional secondary resonance vibration or the torsional tertiary resonance vibration.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of a vibrator in a direction of a central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting around the central axis. A dimension ratio of a rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration match. The vibrator includes a plurality of regions in a surface orthogonal to the central axis, and deformations of the regions adjacent to each other along the direction of the central axis are mutually different. The vibrator expands and contracts in a direction orthogonal to a polarization direction thereof.

Abstract: A oscillator include: a vibrator that vibrates in a thickness shear vibration mode; a first adsorption film formed in a first region in a first surface of the vibrator; a second adsorption film formed in a second region in a second surface of the vibrator opposing to the first surface; and a substrate with a surface on which the vibrator is erected, wherein the vibrator contacts the substrate in a third surface that is different from the first surface and the second surface.

Abstract: To provide an elastic wave device that is small sized and in which a frequency fluctuation due to a change with time hardly occurs, and an electronic component using the above elastic wave device. A trapping energy mode portion 2 provided in an elastic wave waveguide 10 made of an elastic body material excites a second elastic wave being an elastic wave in an energy trapping mode by a specific frequency component included in a first elastic wave being an elastic wave in a zero-order propagation mode propagated from a first propagation mode portion 4, and a cutoff portion 3 provided in a peripheral region of the trapping energy mode portion 2 has a cutoff frequency being a frequency higher than that of the second elastic wave. A second propagation mode portion mode-converts the second elastic wave leaked through the cutoff portion to a third elastic wave being the elastic wave in the zero-order propagation mode to propagate the third elastic wave.

Abstract: An ultrasonic method for removing and/or avoiding unwanted build-up on structures is provided, wherein the term build-up refers to, but is not limited to, ice, dirt, mud, or other wanted debris or contamination. Deicing or anti-icing structures of interest can include, but are not limited to, helicopter rotor blades, other helicopter blade components, fixed wing aircraft components, windshields in aircraft, automobiles, and other vehicles, ship hulls or other ship components, heat exchangers and other tubing where frost or ice could form, air-conditioning components, head lamp and other light coverings, bridge structures and components, and any structure where anti-icing or deicing would be beneficial. One or more ultrasonic actuators permanently embedded or coupled to the structure may be used accomplish the removal. The technique presented herein could also be utilized for non-destructive evaluation and structural health monitoring applications.

Abstract: A driving mechanism includes a first piezoelectric element that vibrates in a thickness-shear vibration mode in a first direction, a first member that is driven to vibrate in the first direction by the first piezoelectric element, a second piezoelectric element that is supported by the first member and that vibrates in the thickness-shear vibration mode in a second direction, and a second member that is driven to vibrate in the second direction by the second piezoelectric element.

Abstract: A mechanical amplifier and method for converting a small motion amplitude to a larger motion amplitude are disclosed. The method includes using two or more beams which are connected in series at angles to each other. Undesirable movements arising in the structure are absorbed by the structure through torsion. Each beam is a mechanical motion amplifier, and by connecting these in series, the total amplification is the product of the amplification of the comprised beams. The disclosure also pertains to a device comprising two or more beams connected together at an angle of 90 degrees in one embodiment.

Abstract: A first conductive polymer film, a plate-shaped first porous member, a second conductive polymer film, and a plate-shaped second porous member are stacked on one another, and the adjacent members are connected with each other on one end portions so as to form a zigzag pattern. The first and second porous members each have an ionic solution injected thereinto so as to function as an electrolyte retention layer, so that operations can be carried out with tensions being always maintained upon both of the expansion and the contraction, and rigidity and a driving force can be exerted in both of the contracting and expanding directions.

Abstract: A process for the preparations of piezoelectric single crystal elements involving the steps of mechanically finishing a single crystal element with select cuttings, coating electrodes on a pair of Z surfaces, poling the single crystal along the 011/axis under a 500V/mm electric field and a product made by the process thereof.

Abstract: A plurality of application specific integrated circuit (ASIC) chips with different functions is provided. Each of the ASICs performs one or more functions along an ultrasound data path. The chips include communications protocols or processes for allowing scaling. For example, ASICs for backend processing include data exchange ports for communicating between other ASICs of the same type. As another example, receive beamformer ASICs cascade for beamformation. By providing ASICs implementing many or most of the ultrasound data path functions, with scalability, the same ASICs may be used for different system designs. A family of systems from high end to low-end using the same types of ASICs, but in different configurations, is provided.

Abstract: Circularly polarized resonant structures are obtained utilizing piezoelectric resonators made of materials and orientations selected in accordance with the teaching provided herewith. Further provided are radially polarized structures. Furthermore, the utilization of such resonators and structures as sensors, for frequency control application, for signal filtering, and the like, is also disclosed.

Abstract: A Micro Electro Mechanical System (MEMS) switch includes a substrate, a fixed signal line formed on the substrate, a movable signal line spaced apart from one of an upper surface and a lower surface of the fixed signal line, and at least one piezoelectric actuator connected to a first end of the movable signal line so as to bring or separate the movable signal line in contact with or from the fixed signal line. The piezoelectric actuator includes a first electrode, a piezoelectric layer formed on the first electrode, a second electrode formed on the piezoelectric layer, and a connecting layer formed on the second electrode and connected with the movable signal line.

Abstract: A process for the preparation of piezoelectric single crystal elements involving the steps of mechanically finishing of a single crystal element with cuttings such as zxt±45°, coating electrodes on a pair of Z surfaces, poling the single crystal in a direction along the <011> axis under a 500V/mm electric field.

Abstract: Making a transducer having a plastic matching layer which includes providing a transducer housing having a proximal end and a distal end, and bonding a plastic to the distal end of the transducer housing (the plastic fluidly sealing and occluding the distal end). The bonding further includes inserting a cylinder comprising a mold-release chemical into the transducer housing, bonding plastic onto the distal end of the transducer housing, and removing the cylinder when the plastic has hardened.

Abstract: A crystal resonator comprises an AT-cut crystal vibrating element that is driven by a thickness-shear mode and is in the shape of a rectangular plate. A pair of excitation electrodes is formed, facing front and rear surfaces of the crystal vibrating element. Each of the excitation electrodes is formed in the shape of a quadrangle as viewed from the top, and mass adjustment portions are formed at least two opposite sides of each of the excitation electrodes formed on the front and rear surfaces.

Abstract: A focused ultrasound transducer includes a first ultrasonic emitter and at least one metallic ultrasonic lens acoustically coupled thereto. The emitter generates ultrasonic energy that propagates along a beam path projecting therefrom. The at least one metallic ultrasonic lens is positioned at least partially in the beam path so that it can direct (e.g., focus, defocus, and/or collimate) in at least one direction (or along at least one plane) at least some of the ultrasonic energy propagating from the emitter. The metallic lens may be formed by extrusion, by molding (e.g., diecast molding or thermoforming), or by sintering (e.g., powder metallurgy). The metallic lens also advantageously functions as a heat sink, improving thermal performance of the ultrasound transducer.

Abstract: A piezoelectric microelectromechanical systems (MEMS) actuator includes a silicon substrate; an actuator beam comprising a first end region connected to the silicon substrate and a second end region connected to a mechanically compliant spring assembly; a first electrode over the silicon substrate; a piezoelectric layer above the first electrode; a second electrode over the piezoelectric layer; a conductive top structural layer above the second electrode, wherein a center half of the actuator beam is configured as a positive deflection region, and wherein both the first electrode and the second electrode supply voltage to both positive and negative deflection regions of the actuator beam.

Abstract: The invention relates to a motorized manipulator for positioning a TEM specimen holder with sub-micron resolution parallel to a y-z plane and rotating the specimen holder in the y-z plane, the manipulator comprising a base (2), and attachment means (30) for attaching the specimen holder to the manipulator, characterized in that the manipulator further comprises at least three nano-actuators (3a, 3b, 3c) mounted on the base, each nano-actuator showing a tip (4a, 4b, 4c), the at least three tips defining the y-z plane, each tip capable of moving with respect to the base in the y-z plane; a platform (5) in contact with the tips of the nano-actuators; and clamping means (6) for pressing the platform against the tips of the nano-actuators; as a result of which the nano-actuators can rotate the platform with respect to the base in the y-z plane and translate the platform parallel to the y-z plane.

Abstract: A rotational actuator includes a plurality of actuation beams each having an offset longitudinal axis with respect to one another; and a coupler connecting the plurality of actuation beams to one another, wherein the coupler is connected to each individual actuation beam at a position where connection of the coupler to other actuation beams causes the longitudinal axis of each actuation beam to be offset with respect to one another, wherein the plurality of actuation beams are lengthened or shortened to cause a moment about the coupler causing rotation of a point in the rotational actuator. The rotational actuator includes an amplification beam connected to the coupler such that the longitudinal axis of the amplification beam is substantially perpendicular to the longitudinal axes of the plurality of actuation beams. Additionally, the rotational actuator includes a resistant spring member connected to the amplification beam. The actuation beams can be thermally or piezoelectrically induced.

Abstract: A precise and high load resistance moving method to perform fine movement positioning of the moving body, by fixing a piezoelectric element which generates a shear deformation, to a bottom surface of a wedge-shaped moving element placed on a base, and deforming the piezoelectric element by driving the piezoelectric element with drive pulses to move the wedge-shaped moving element along a first axis in which the wedge-shaped moving element drives into or away from a moving body to move the moving body along a second axis in upward and downward direction relative to the base. Also, a precise and high load resistance moving device including a wedge-shaped moving element, a pulse source, and a moving body vertically movable in upward or downward direction relative to the base.

Abstract: A composite acoustic wave device (AWD) which is adapted for operation at high ambient pressures is provided. The AWD comprises two piezoelectric plates in back to back relationship, with electrodes disposed between the plates. The plates are bonded so as to neutralize the effects of external pressure. Further disclosed is a sensor utilizing the AWD and methods for utilizing such AWD for physical measurements in high pressure environments. An optional cavity formed between the piezoelectric plates offers the capability to measure the pressure and to further neutralize the residual effects of the pressure on measurement accuracy.

Abstract: In a polymer actuator provided with a first polymer structural member having a conductive property, an electrolyte retention layer electrically connected to the first polymer structural member, and a second polymer structural member electrically connected to the first polymer structural member through the electrolyte retention layer interposed therebetween and having a conductive property, and by applying a potential difference between the first polymer structural member and the second polymer structural member, the first polymer structural member and the second polymer structural member are allowed to expand and contract, by displacement of the second polymer structural member, the potential difference between the first polymer structural member and the second polymer structural member is changed.

Abstract: To provide a screw fastening device that, when performing a screw tightening operation, can substantially reduce the running torque directly applied by external force 5 to a screw driving device.

Abstract: Circularly polarized resonant structures are obtained utilizing piezoelectric resonators made of materials and orientations selected in accordance with the teaching provided herewith. Further provided are radially polarized structures. Furthermore, the utilization of such resonators and structures as sensors, for frequency control application, for signal filtering, and the like, is also disclosed.

Abstract: The present invention relates to a sandwich-structure flat active actuator that is symmetrical relative to the mid-plane comprising at least one piezoelectric flat layer having an active direction superpose and fixedly attached to at least one passive flat layer of fabric with rigid warp and weft oriented in two directions forming a mesh; the two directions of each layer of fabric are the same. The active direction of each piezoelectric layer is oriented along one and the same diagonal of the mesh of the layers of fabric. The invention is also aimed at a device consisting of two actuators mounted head-to-tail. The invention applies to the active torsion of structures such as, for example, a helicopter blade.

Abstract: A capacitive ultrasonic transducer includes a flexible layer, a first conductive layer on the flexible layer, a support frame on the first conductive layer, the support frame including a flexible material, a membrane over the support frame being spaced apart from the first conductive layer by the support frame, the membrane including the flexible material, a cavity defined by the first conductive layer, the support frame and the membrane, and a second conductive layer on the membrane.

Abstract: Conductive polymer films are respectively connected to fixed frames via a link member, and an electrolyte holding layer is placed so as to be made in contact with the conductive polymer films. The fixed frames are regulated by the link member.

Abstract: A method includes a step of stacking a first electrode layer, a piezoelectric layer, and a second electrode layer on a first substrate to form a first laminate; a step of stacking a support layer on a second substrate to form a second laminate; a step of bonding the first and second laminates through an adhesive layer to form a third laminate; a step of removing the first substrate from the third laminate; a step of processing the third laminate in a desired shape; and a step of removing the second substrate. A Young's modulus of the adhesive layer is smaller than a Young's modulus of the piezoelectric layer. Respective Young's moduli of the second electrode layer and the support layer are larger than the Young's modulus of the adhesive layer. The third laminate has no other piezoelectric layer except for the aforementioned piezoelectric layer.

Abstract: A composite structure of a backing material with enhanced conductivity for use in a transducer is presented. The composite structure includes a plurality of layers of backing material alternatingly arranged with a plurality of thermal conductive elements, wherein the plurality of thermal conductive elements are configured to transfer heat from a center of the transducer to a plurality of points on the composite structure of backing material.

Abstract: A method of fabricating a polymer-based capacitive ultrasonic transducer, which comprises the steps of: (a) providing a substrate; (b) forming a first conductor on the substrate; (c) coating a sacrificial layer on the substrate while covering the first conductor by the same; (d) etching the sacrificial layer for forming an island while maintaining the island to contact with the first conductor; (e) coating a first polymer-based material on the substrate while covering the island by the same; (f) forming a second conductor on the first polymer-based material; (g) forming a via hole on the first polymer-based material while enabling the via hole to be channeled to the island; and (h) utilizing the via hole to etch and remove the island for forming a cavity.

Abstract: The invention relates to a nanomanipulator that is used for analyzing or machining objects. Said nanomanipulator is equipped with several moving elements which can be adjusted to perform movements and support the object that is to be moved or an object holder in order to move at least one object relative to an analyzing position or machining position. Each of said moving elements is provided with one support area for the object that is to be moved or the object holder. The moving elements support at least one load-bearing plane in an axial direction of the nanomanipulator. The inventive nanomanipulator is characterized by moving elements comprising shearing piezo elements so as to move the load-bearing plane.

Abstract: A thickness shear mode (TSM) resonator is described, comprising a diamond layer. The diamond layer is preferably a high quality diamond layer with at least 90% sp3 bonding or diamond bonding. A method for manufacturing such a resonator is also described. The thickness shear mode resonator according to embodiments described herein may advantageously be used in biosensor application and in electrochemistry applications.

Abstract: This invention provides a shear mode-type piezoelectric actuator using a piezoelectric ceramic composition free from lead having a high coercive electric field and a liquid ejection head having the shear mode-type piezoelectric actuator. The shear mode-type piezoelectric actuator is characterized by using a piezoelectric ceramic composition having a solid solution including a main component of general formula (1) and an auxiliary component of general formula (2) added in an amount of less than 1% by mole based on the total amount of the solid solution: {LiX(K1-YNaY)1-X} (Nb1-Z-WTaZSbW)O3 ??General Formula (1) (Wherein 0?x?0.2, 0?y?1, 0<z?0.4, 0<w?0.2) ABO3 ??General Formula (2) (Wherein A denotes Bi and B denotes at least one of Fe, In and Sc).

Abstract: A precise and high load resistance moving method to perform fine movement positioning of the moving body, by fixing a piezoelectric element which generates a shear deformation, to a bottom surface of a wedge-shaped moving element placed on a base, and deforming the piezoelectric element by driving the piezoelectric element with drive pulses to move the wedge-shaped moving element along a first axis in which the wedge-shaped moving element drives into or away from a moving body to move the moving body along a second axis in upward and downward direction relative to the base. Also, a precise and high load resistance moving device including a wedge-shaped moving element, a pulse source, and a moving body vertically movable in upward or downward direction relative to the base.

Abstract: An electroacoustic transducer having a tail mass, a head mass and at least two parallelepiped shaped piezoelectric material elements disposed between and attached to the tail mass and the head mass is provided. The tail mass has a body extending between a first end and a second end, the body having a cavity with a cavity wall and the cavity extending from the first end towards the second end. The head mass has a head and an elongated shaft attached to and extending from the head, the shaft having a shaft axis and being located at least partially within the cavity of the tail mass. The at least two parallelepiped shaped piezoelectric material elements are made from a piezoelectric material having a non-zero d3y shear piezoelectric coefficient where the d3y coefficient can be d34, d35 or d36.

Abstract: A method of manufacturing an ultrasonic sensor including a case, a piezoelectric element having first and second electrodes, and a conductive member having first and second conductive parts is disclosed. The method includes the steps of a) forming the conductive member by integrally forming the first and second conductive parts and a joining part that joins portions of the first and second conductive parts, b) mounting the piezoelectric element and the conductive member in the case so that the first conductive part is connected to the first electrode and the second conductive part is connected to the second electrode, and the joining part and the portions of the first and second conductive parts joined by the joining part are positioned outside of the case, c) supplying a filling material into the case, and d) removing the joining part after step c).

Abstract: An energy-trapping strip piezoelectric vibrator utilizing a third harmonic overtone of a thickness shear mode is provided. A piezoelectric vibrator 1 has a strip piezoelectric ceramic substrate 2 polarized in a longitudinal direction, and first and second excitation electrodes 3 and 4 provided on first and second principal surfaces 2a and 2b of the piezoelectric ceramic substrate 2. An excitation region 5 including a piezoelectric vibration portion that includes a portion where the first and second excitation electrodes 3 and 4 overlap and that utilizes harmonics of the thickness shear mode is formed. A region around the piezoelectric vibration portion is set as a non-excitation region. At least a region of the non-excitation region neighboring the piezoelectric vibration portion is a region having the same polarization axis direction as the excitation region 5 and a relatively small polarization degree or is an unpolarized region.

Abstract: The present invention relates to an ultrasonic probe including a piezoelectric element, a first acoustic matching layer provided on the front face of the piezoelectric element and formed of a solid inorganic material, and a second acoustic matching layer provided on the first acoustic matching layer and formed of a mixture of an organic resin and 10 to 30% by volume of oxide powder with a density of 6.5 g/cm3 or more.

Abstract: An oscillator device and a method of producing the same, that enables adjustment of an inertia moment or a gravity center position of an oscillating member through wide range and at high speed, wherein the oscillating member oscillates about an oscillation axis 17 and it includes a movable element 11 and a mass adjusting member 19, a cavity 30 being defined between the movable member 11 and a portion of the mass adjusting member 19, such that, in response to irradiation of the mass adjusting member 19 with a laser beam, a material of the mass adjusting member contiguous to the cavity 30 is partly removed, the material being removed thereby including a portion of the mass adjusting member not irradiated with the laser beam.

Abstract: A drive mechanism according to the present invention includes: a drive body that defines a longitudinal direction; a mover that makes a friction fit with the drive body so as to slide in the longitudinal direction; a base member that supports the drive body so as to allow the drive body to move in the longitudinal direction; a drive element, which is secured to one end of the drive body to vibrate the drive body in the longitudinal direction; and a viscoelastic body, which is arranged between the drive body and the base member in a direction perpendicular to the longitudinal direction.

Abstract: In a polymer actuator provided with a first polymer structural member having a conductive property, an electrolyte retention layer electrically connected to the first polymer structural member, and a second polymer structural member electrically connected to the first polymer structural member through the electrolyte retention layer interposed therebetween and having a conductive property, and by applying a potential difference between the first polymer structural member and the second polymer structural member, the first polymer structural member and the second polymer structural member are allowed to expand and contract, by displacement of the second polymer structural member, the potential difference between the first polymer structural member and the second polymer structural member is changed.

Abstract: A high performance MEMS scanner is disclosed. In some embodiments, scanner mirror has a wide and short aspect ratio that is similar to rotating polygon facets. Long torsion arms allow large rotation angles including 20° zero-to-peak mechanical and greater. Suspensions couple the scan mirror to torsion arms, reducing dynamic mirror deformation by spreading the torque load. “leverage members” at the distal ends of the torsion arms help reduce stress concentrations. Elimination of a mounting frame increases device yield. Heater leads allow for precise trimming of the scanner resonant frequency. A compressive mount holds mounting pads against mounting structures.

Abstract: Disclosed is an oscillating device that includes an oscillating system having a plurality of oscillation movable elements, a plurality of elastically supporting portions connected to the oscillation movable elements, and a supporting member for supporting a predetermined portion of the plurality of resiliently supporting portions so that predetermined oscillation movable element or elements are resiliently supported for oscillation about a predetermined oscillation axis, the device further including a driving circuit for driving the oscillating system and a temperature adjusting element for adjusting temperature of the resiliently supporting portions, wherein the oscillating system has a plurality of natural oscillation modes of different frequencies, and wherein the driving circuit functions to oscillate the predetermined movable element about the predetermined oscillation axis, in different natural oscillation modes simultaneously.

Abstract: An electroacoustic transducer having a tail mass, a head mass and at least two parallelepiped shaped piezoelectric material elements disposed between and attached to the tail mass and the head mass is provided. The tail mass has a body extending between a first end and a second end, the body having a cavity with a cavity wall and the cavity extending from the first end towards the second end. The head mass has a head and an elongated shaft attached to and extending from the head, the shaft having a shaft axis and being located at least partially within the cavity of the tail mass. The at least two parallelepiped shaped piezoelectric material elements are made from a piezoelectric material having a non-zero d3y shear piezoelectric coefficient where the d3y coefficient can be d34, d35 or d36.