Abstract: A method for dynamically reconfiguring elements in an ultrasound transducer array is provided. The method includes defining two or more groups of the elements in the array, wherein each element individually comprises a first switch, and a second switch; providing boundary definitions information to the elements in the array to define boundaries for the two or more groups; and locally determining switch configuration state within the array for the first and second switch of one or more elements based on the boundary definitions. Further, a switch matrix configured to locally determine switch settings is provided. Furthermore, a system comprising an array of ultrasonic transducer subelements is provided.

Abstract: An ultrasound transducer comprises a multiplicity of piezoelectric transducer elements attached to a backing layer and forming a two-dimensional array, the transducer elements each comprising one or more piezoelectric members that collectively form an energy transmitting surface of the respective transducer element, the energy transmitting surface having a geometric center, wherein the respective transducer element geometric centers are in an irregular formation.

Abstract: An ultrasonic transducer includes a piezoelectric resonator including a pair of electrodes sandwiching a piezoelectric body and provided with the backing layer in contact with one of the electrodes of the piezoelectric resonator and having the same acoustic characteristic impedance as the piezoelectric body. A method includes the step of driving the ultrasonic transducer so as to satisfy a condition: 2Th?Td?6Th where Th is a propagation time of an ultrasonic wave in the piezoelectric body sandwiched by the pair of electrodes, and Td is a pulse width of a drive pulse driving the piezoelectric resonator.

Abstract: A hybrid drive (HD) multi-mode pipe projector (MMPP) for use in underwater acoustic applications is provided. The HD MMPP is formed with an inner magnetostrictive drive motor nested within an outer drive motor. The inner motor is surrounded by a magnetic field generating coil winding. Preferably the inner drive motor is a Terfenol-D motor and the outer drive motor is a radially-poled piezoceramic drive motor. This nested configuration provides increased bandwidth and low-frequency extension to the MMPP design.

Abstract: A slotted cylinder acoustic transducer has a crescent-shaped insert disposed between a ceramic stack assembly and s cylindrical housing shell. In some embodiments, all of the ceramic elements in the ceramic stack assembly can have the same shape.

Abstract: A transducer, system and method of constructing the same that utilizes a composite of piezoelectric pillars. In one embodiment, the invention is an apparatus for generating acoustic energy comprising: a plurality of pillars constructed of a piezoelectric material, the pillars arranged in a spaced-apart manner so that spaces exist between adjacent pillars; the pillars having a width and a height extending between a top surface and a bottom surface, wherein the height of the pillars is greater than the width of the pillars; and the spaces filled with a resilient material so as to form a composite assembly.

Abstract: One or more chips, integrated circuits, or semiconductors are embedded within a backing block. Planar sheets of backing material are formed with integrated circuits within holes in the sheets. Traces connect the integrated circuit to electrodes or exposed conductive surfaces. A plurality of the planar sheets may be manufactured using wafer processing, such as pick and place of chips in a wafer of backing material and IC redistribution for forming the traces. The different sheets are cut from the wafer and stacked adjacent each other. The transducer connects with the exposed electrodes or conductive surfaces of the backing.

Abstract: A cymbal array for underwater vehicle applications includes piezoelectric discs disposed in a line, a first flex circuit comprising first annular members each affixed to a first side of one of the discs, a first series of cymbal caps each mounted on one of the first annular members, a second flex circuit comprising second annular members each fixed to a second side of one of the discs, and a second series of cymbal caps each mounted on one of the second annular members. The flex circuits each comprise an electrically conductive layer disposed between two electrically insulative layers.

Abstract: An ultrasonic transducer in which electrodes can be easily and positively joined to a multiplicity of micro-fabricated vibrators and electric wiring can be easily and positively provided. The ultrasonic transducer has a vibrator arrangement having vibrators provided in a predetermined arrangement, each vibrator having first and second electrodes; an interlayer board for holding the vibrator arrangement in which through-holes are respectively formed in positions corresponding to the second electrodes of the vibrators; and a wiring board having a plurality of electrodes electrically connected to the second electrodes of the vibrators through the through-holes formed in the interlayer board, respectively.

Abstract: A piezoelectric transducer for an ultrasonic scan is provided. The transducer includes a plurality of piezoelectric members arrayed. The plurality of piezoelectric members have different compositions parts in a slice direction so that an ultrasonic beam is focused in the slice direction.

Abstract: A piezoelectric transducer for an ultrasonic scan is provided. The transducer includes a plurality of piezoelectric members arrayed. The plurality of piezoelectric members have different compositions parts in a slice direction so that an ultrasonic beam is focused in the slice direction.

Abstract: A transducer for use in an acoustic energy cleaner is provided. The transducer includes a resonator and a plurality of crystals bonded to a surface of the resonator. The plurality of crystals is configured to be bonded to the surface of the resonator in a staggered arrangement with respect to each other. In one embodiment, the plurality of crystals is bonded to the surface of the resonator in a horizontally staggered arrangement. In another embodiment, the plurality of crystals is bonded to the surface of the resonator in a vertically staggered arrangement.

Abstract: A generally pyramid shaped sound module is provided that is attachable to a balloon for producing hi-fidelity sound effects. The sound module includes a piezoelectric element connected at the top of the pyramid shaped piezo amplification device. An electric circuit is connected to the piezoelectric element by wires. The electric circuit includes a power supply, such as one or more batteries, and the circuitry necessary for producing or reproducing a desired sound (e.g. musical notes, voices, sounds, prerecorded sound, a combination of the aforementioned, etc.). The pyramid shape allows the piezoelectric element to be coupled to the balloon without physically touching the balloon surface. Thus, even when the balloon begins to deflate, the sound quality of the sound module can be maintained.

Abstract: The present invention relates to composite piezoelectric apparatus, transducers and methods of manufacture. In an embodiment, a composite piezoelectric apparatus has a sacrificial base and pillar array. Different volume percents of piezoelectric material are used in the sacrificial base and pillar array. A first volume percent in the base is lower than the second volume percent in the pillar array. In this way, the sacrificial base can be easily removed from the pillar array after the base and pillar array are sintered in the manufacture of a final composite piezoelectric transducer. A method of manufacturing a composite piezoelectric transducer from a sacrificial base and pillar array and a composite piezoelectric transducer made by the method are provided. A composite piezoelectric transducer stack is provided.

Abstract: A sound emitting device for providing at least one new sonic or subsonic frequency as a by-product of emitting a waveform of at least two ultrasonic frequencies whose difference in value corresponds to the desired new sonic or subsonic frequency. The device includes a parametric emitting perimeter or plurality of emitter segments positioned around a central open section. This open section is structured with a diagonal width greater than a cross-sectional diagonal of the parametric emitting perimeter. An ultrasonic frequency signal source and sonic/subsonic frequency generator are coupled together to a modulating circuit for mixing an ultrasonic frequency signal with an electrical signal corresponding to the at least one new sonic or subsonic frequency. The modulator output is coupled to the emitting perimeter which comprises ultrasonic frequency emitting material for propagating the mixed waveform into air for demodulating the waveform to generate the at least one new sonic or subsonic frequency.

Abstract: A transducer assembly for receiving a stimulating signal and producing ultrasound therefrom at one or more frequencies, over an ultrabroad bandwidth at each frequency, includes a front mass disposed about a central axis, and a back mass disposed about the central axis, laterally offset from the front mass. The transducer assembly also includes one or more resonators disposed about the central axis and between the front mass and the back mass, including at least one electrical contact for receiving the stimulating signal. The back mass consists of a low-density material, such as aluminum, aluminum alloy, magnesium, or magnesium alloy, or any of various low-density materials known in the art. In general, the back mass is characterized by a density of less than 6.0 g/cc. In one embodiment, the front mass and the back mass are made from different materials, and the front mass includes a deviation from symmetrical symmetry.

Abstract: A multi-layer composite transducer array includes at least one pair of composite transducers with an electrical and mechanical isolation layer disposed therebetween. Each composite transducer is defined by a composite panel having a common electrode coupled to a first surface and electrode segments electrically isolated from one another and coupled to a second surface. Each pair of composite transducers is configured such that the electrode segments associated with the pair's composite transducers oppose and are aligned with one another. The isolation layer has dielectric material segments that are sized, shaped and aligned in correspondence with opposing and aligned ones of the electrode segments associated with the pair's transducers. Spaces formed in the isolation layer between the dielectric material segments are filled with a viscoelastic material.

Abstract: Scaling may be reduced during oil and gas production using a device having a sound transducer. The device can be used downhole and functions independently of an external power supply. Use of the device allows for the reduction or elimination of anti-scaling chemical additives during the production phase of an oil and gas well.

Abstract: A piezoelectric/electrostrictive (P/E) device includes a pair of mutually opposing metal thin plate sections, a movable section, and a fixation section for supporting the thin plate sections and the movable section. One or more piezoelectric/electrostrictive elements are arranged on at least one thin plate section of the pair of thin plate sections. Any one of the movable section and the fixation section has mutually opposing end surfaces, and a distance between the end surfaces is not less than the axial length of the movable section.

Abstract: An ultrasound transducer array includes a multiplicity of subelements interconnected by a multiplicity of microelectronic switches, each subelement comprising a respective multiplicity of micromachined ultrasound transducer (MUT) cells. The MUT cells within a particular subelement are hard-wired together. The switches are used to configure the subelements to form multiple concentric annular elements. This design dramatically reduces complexity while enabling focusing in the elevation direction during ultrasonic image data acquisition.

Abstract: The invention relates to hull sonars for a naval vessel. The hull sonar includes associating a transmitter formed by cylindrical rings with a receiver formed by at least two sets of hydrophones distributed over two transparent cylindrical surfaces that are coaxial with the transmitter. Thus, it is possible to reduce the weight and the total volume of the antenna and to compensate for the effect of the quality factor Q.

Abstract: A dynamically configurable ultrasound transducer element and related circuits and methods. The transducer may comprise an array of capacitive transducer elements, a row decoder coupled to said array of capacitive transducer elements, a column decoder coupled to said array of capacitive transducer elements, a bias voltage source coupled to said row decoder, and a driving signal source coupled to said column decoder. Preferably, a master clock also is provided to allow for a synchronization of signals between the row decoder and column decoder.

Abstract: A modular interferometric imaging system includes a sensor array that senses a physical parameter and provides a plurality of first sensor array output signals indicative thereof. An analog die receives the plurality of first sensor array output signals, and digitizes and modulated each of the first sensor array signals to provide a plurality of digitized signals. A digital die receives the plurality of digitized signals to provide a plurality of received digitized signals, and demodulates the plurality of received digitized signals to provide a plurality of demodulated digitized signals indicative thereof. A processor receives and processes the demodulated digitized signals to provide an imaging system output signal.

Abstract: A three-dimensional array of acoustic sensors. The array can be used for both the transmission and reception of acoustic signals. The array comprises electroplated piezoelectric polymer layers that are laminated with a non-conductive epoxy to form individual multi-layer array transducer elements. Circuit support layer layers are incorporated between the multi-layer array transducer elements. Because of the three-dimensional configuration of the array, logical transducers can be created from multiple transducer elements, and transmission and reception of acoustic signals in any direction can be realized.

Abstract: An ultrasound radiating and receiving device comprises a piezoelectric substrate, an interdigital arrangement of first and second comb-shaped electrodes, and a counter electrode. The interdigital arrangement is mounted on an upper end surface of the piezoelectric substrate. The counter electrode is formed on a lower end surface of the piezoelectric substrate, and is in contact with a surface-part of a material through the lower end surface of the counter electrode. When an input electric signal is applied between the first comb-shaped electrode and the counter electrode, a longitudinal wave is radiated into the material through the surface-part of the material along the direction vertical to the lower end surface of the piezoelectric substrate. If the longitudinal wave is reflected at an object located inside the material, a reflected longitudinal wave is detected between the second comb-shaped electrode and the counter electrode as a delayed electric signal.

Abstract: A generally pyramid shaped sound module is provided that is attachable to a balloon for producing hi-fidelity sound effects. The sound module includes a piezoelectric element connected at the top of the pyramid shaped piezo amplification device. An electric circuit is connected to the piezoelectric element by wires. The electric circuit includes a power supply, such as one or more batteries, and the circuitry necessary for producing or reproducing a desired sound (e.g. musical notes, voices, sounds, prerecorded sound, a combination of the aforementioned, etc.). The pyramid shape allows the piezoelectric element to be coupled to the balloon without physically touching the balloon surface. Thus, even when the balloon begins to deflate, the sound quality of the sound module can be maintained.

Abstract: A dynamically configurable ultrasound transducer element and related circuits and methods. The transducer may comprise an array of capacitive transducer elements, a row decoder coupled to said array of capacitive transducer elements, a column decoder coupled to said array of capacitive transducer elements, a bias voltage source coupled to said row decoder, and a driving signal source coupled to said column decoder. Preferably, a master clock also is provided to allow for a synchronization of signals between the row decoder and column decoder.

Abstract: This transducer comprises means (16 to 24, 56 to 60) for determining the respective positions of ultrasound emitting elements (6) with respect to an object to be inspected (8) during displacement of the transducer. Means (62) generate pulses exciting emitting elements, and create delay laws starting from determined positions enabling emitting elements to generate a focused ultrasonic beam (F), and apply these laws to the excitation pulses. Ultrasound receiving elements provide signals used to form images related to the object. Application to medicine and nondestructive testing.

Abstract: A method of manufacturing a multiple-element acoustic probe including piezoelectric transducers and an array of interconnections connecting the transducers to an electronic signal processing and control device. The probe also includes a continuous ground electrode integrated between the transducers and the acoustic matching elements, facing the piezoelectric transducers, the acoustic matching elements being totally uncoupled from one another mechanically. This probe may be used in medical imaging or underwater imaging.

Abstract: A generally cylindrical hydrophone configuration provides compensation for longitudinal accelerations by placing four identical solid piezoelectric transducer elements along its axis with each transducer element being bonded to a head member, two of which are located generally centrally of the cylindrical housing and fastened thereto and two of which are located near the outside edges of the housing and having slight clearance therewith. Flexible polyurethane boots are clamped to the ends of the housing. The volumes between the centrally disposed and outer transducer head members and between the outer head members and the boots are filled with methyl silicon fluid. Each head member is electrically connected to one side of the electrical output, and the junction between the transducer members is connected to the opposite side, both sides being wired to an electrical contact plate located between the two centrally disposed transducer head members, this volume being filled with electrical potting material.

Abstract: An electroacoustic transducer 1 is configured by: a base 24 made of a magnetic material; a magnetic core 22 made of a magnetic material and upstanding from the base 24; a diaphragm 20 made of a magnetic material and spaced from the tip end of the magnetic core by a gap; a magnet 25 which cooperates with the base 24, the magnetic core 22 and the diaphragm 20 to constitute a magnetic circuit, and which supplies a static magnetic field; a coil 23 wound around the magnetic core 22, and supplying an oscillating magnetic field to the magnetic circuit; and a housing 30 formed integrally with the base 24 and the magnet 25. The housing 30 is interposed between the base 24 and the magnet 25, and the plan-view shape of the base 24 has a portion which elongates more outwardly than the width center of the magnet 25.

Abstract: A method of producing an acoustically absorbing anisotropic backing structure for an ultrasound transceiver is disclosed. Laser machining of a substrate of acoustically absorbent electrically resistive material produces a set of vias and indented pad seats. The machined substrate is plated with an electrically conductive material. Excess electrically conductive material is removed from the substrate to leave an electrically conductive material plating on the indented pad seats and the vias to form conductive pads and plated vias on the substrate.

Abstract: A piezoelectric acoustic device capable of keeping a substantial diameter of a metal vibrating plate from being reduced and preventing clogging of a damping cloth member. The piezoelectric acoustic device includes a piezoelectric vibrator including a metal vibrating plate and a piezoelectric ceramic element joined to the metal vibrating plate. The piezoelectric vibrator is arranged in a casing which is formed on an inner peripheral surface thereof with an inclined joint surface section of an annular shape which surrounds an outer peripheral portion of the metal vibrating plate. The piezoelectric acoustic device also includes a pressure-sensitive adhesive layer formed by coating a pressure-sensitive adhesive on the inclined joint surface section. The outer peripheral portion of the metal vibrating plate is joined through the pressure-sensitive adhesive layer to the inclined joint surface section.

Abstract: There is provided an acoustic source especially for use in seismic studies at sea. The acoustic source has a longitudinal axis and sound emitting surfaces adapted to be put into sound emitting movements towards and away from each other by use of a drive unit. The sound emitting surfaces comprise two curved plate members having upper and lower ends essentially symmetrically positioned in relation to the longitudinal axis of the acoustic source, and forming a convex cross section with their respective upper and lower edges converging towards each other. The upper and lower edges of the sound emitting surfaces, respectively, are connected to each other with two corresponding side elements, the side elements each being connected to at least one hinge stretching along at least a part of the length of the source.

Abstract: A method of fabricating one or more arrays of bio-molecule test sites including providing a solution containing bio-molecule probes in contact with the surface of a substrate, using orthogonal acoustic waves to concentrate the bio-molecule probes at a node intersection, bonding the bio-molecule probes on the substrate at the node intersection to form a test site, and removing the solution leaving the bio-molecule probes attached to the surface at the test site. The steps are repeated as often as desired, using different bio-molecule probes, to produce one or more arrays of test sites.

Abstract: A sonar sensor array having a multi-layer tiling arrangement for the indiual elements that increases surface area available for each element while maintaining the inter-element spacing required to avoid spatial aliasing when the received signals are combined to form a sonar beam. The array comprises outer and inner arrays of transducer elements for converting an acoustic signal to an electrical response. The transducer elements of the outer array are positioned such than a grid of isolation spaces separates each of the transducer elements. The transducer elements of the inner array are also positioned such that a grid of isolation spaces separates each one of the transducer elements. The electrical response generated by the transducer elements of the inner and outer arrays are coupled to a beamformer which processes the responses to produce an output signal.

Abstract: Acoustic source, especially for use in seismic studies at sea, with sound emitting surfaces adapted to be put into sound emitting movements toward and away from each other by use of a drive unit in a known manner, in which the sound emitting surfaces comprise two curved plate members essentially symmetrically positioned in relation to the longitudinal axis of the source, forming a convex cross section with their respective upper and lower edges converging towards each other, and the respective upper and lower edges of the sound emitting surfaces are flexibly connected to two corresponding side elements positioned between them, and that the source comprises a rigid frame for supporting the drive unit, comprising at least two rigid slide rods stretching through the side elements, and that rigid covers are mounted on the slide rods, covering at least the whole side elements, thus forming rigid, covering surfaces with a constant distance between the covers.

Abstract: Sonar suspension apparatus comprising a flotation buoy and an underwater sonar array connected to the flotation buoy by a suspension cable, wherein the sonar array comprises a plurality of transducer-carrying elongate members including at least one rigid arm and at least one flexible line.

Abstract: In a composite ultrasonic transducer, each of a plurality of piezoelectric ceramic columns included in a resin plate has a given circular cross-section and passes through the resin plate in a direction of a thickness of the resin plate, and central axes of the piezoelectric ceramic columns are regularly arranged at positions corresponding to nodes of a regular triangle network.

Abstract: Methods for fabricating a conformable composite acoustic transducer panel including a conformable composite body having upper and lower planar faces and upper and lower thin, flexible electrodes bonded to the upper and lower faces, respectively. The composite body includes an array of individual piezoelectric or electrostrictive ceramic elements extending normal to the upper and lower faces and through the composite body from the upper face to the lower face to electrically contact the electrodes. Stiff integral face plates are bonded to the side surfaces of the elements at their upper and lower ends. Alternatively, a conformable, stiff, voided polymer matrix is bonded to the element sides over their entire length. Flexible circuit boards may be bonded to the electrodes to provide electrical contact thereto.

Abstract: There is provided a two-dimensional array for use in an acoustic imaging system which comprises a plurality of transducer segments each having a trace for exciting an electrode on each of the transducer segments, the trace and the electrode being formed of the same material. The two-dimensional array disclosed is capable of imaging deeper in the human body at higher frequencies and provides more reliable lead attachments to the respective segments forming the array. Methods of manufacturing the two-dimensional array are further provided.

Abstract: A sonar array uses multiple acoustically transparent layers. One layer is a lanar array of acoustic sensors that is substantially acoustically transparent. Another layer is an acoustically transparent wiring assembly that provides electrical connection to each acoustic sensor. A third acoustically transparent layer is a planar array of signal processing circuits coupled to the wiring assembly for processing electrical signals generated by the acoustic sensors. Each signal processing circuit resides within an area that is in geometric correspondence with a respective one acoustic sensor. Each signal processing circuit can include a preamplifier, an analog-to-digital converter and a digital multiplexer.

Abstract: The invention relates to underwater acoustic transmitters intended to be submerged at large depths. It consists in threading the set of annuli forming the transmitter onto an internal tube (303) preferably made from a carbon/resin composite, which supports two end plugs (306, 307) making it possible to relieve the set of annuli of the radial component of the hydrostatic pressure. Furthermore, between the piezoelectric annuli (101) of the transmitter are inserted decoupling annuli (301) which are made as a three-layer structure including a hard and rigid internal layer (201) and two flexible and elastic external layers (202, 203). It makes it possible to increase the transmitting power of these acoustic transmitters.

Abstract: A transducer array is constructed from a constant arc length portion of a ght circular cylindrical shell of piezoelectric transduction material. The constant arc length portion is segmented evenly along the length thereof to define a plurality of transducers. The transducers can be in the free field or mounted on a planar baffle.

Abstract: There is provided a two-dimensional array for use in an acoustic imaging system which comprises a plurality of transducer segments each having a trace for exciting an electrode on each of the transducer segments, the trace and the electrode being formed of the same material. The two-dimensional array disclosed is capable of imaging deeper in the human body at higher frequencies and provides more reliable lead attachments to the respective segments forming the array. Methods of manufacturing the two-dimensional array are further provided.

Abstract: An ultrasonic device for detecting concentrations of solids or positions of solid/liquid interfaces in liquid media, particularly Bayer process liquids. The device comprises at least one piezoelectric element provided with electrodes; electrical circuit elements connected to the electrodes for conveying electrical signals, in use, to and from control apparatus; an ultrasound-transparent window, made of glassy carbon, positioned adjacent to the or each piezoelectric element; a protective matrix, preferably of epoxy resin, embedding and surrounding said the or each piezoelectric element and the electrodes while allowing ultrasonic waves to pass through the or each adjacent window to or from the piezoelectric element, and an external protective cover, preferably comprising an elastomer that is resistant to caustic alkali and has a smooth and non-porous surface, forming an exterior of the device except at the or each window.

Abstract: A retractable sensor array system is used to provide a large aperture sen array, such as a sonar array, that receives acoustic energy in a deployment medium. The retractable sensor array system includes one or more sensor array sheets having one or more sensors and a sensor array positioning mechanism for deploying and retracting the sensor array sheet from a platform, such as a ship, submarine, aircraft, space vehicle or medical device. The sensor array positioning mechanism preferably includes a motor that automatically and selectively deploys and retracts the one or more sensor array sheets by rolling and unrolling the sensor array sheets. The retractable sensor array system allows the one or more sensor array sheets to be deployed from various locations on a platform and also in various directions from the platform depending upon the desired usage, platform orientation, position and deployment medium conditions.

Abstract: A method for fabricating "1.5D" and "2D" multilayer ultrasonic transducer arrays employs dicing saw kerfs, which provide acoustic isolation between rows. The kerfs are metallized to provide electrical connection between surface electrode layers and buried internal electrode layers. A multilayer piezoceramic transducer element for a "1.5D" or "2D" array produced by this method has higher capacitance, and accordingly provides better transducer sensitivity, in comparison to a single layer element.

Abstract: A conformable composite acoustic transducer panel including a conformable composite body having upper and lower planar faces and upper and lower thin, flexible electrodes bonded to the upper and lower faces, respectively. The composite body includes an array of individual piezoelectric or electrostrictive ceramic elements extending normal to the upper and lower faces and through the composite body from the upper face to the lower face to electrically contact the electrodes. Stiff integral face plates are bonded to the side surfaces of the elements at their upper and lower ends. Alternatively, a conformable, stiff, voided polymer matrix is bonded to the element sides over their entire length. Flexible circuit boards may be bonded to the electrodes to provide electrical contact thereto. Methods for fabricating the transducer panel are also disclosed.

Abstract: In fabricating a two-dimensional array transducer wherein individual preformed piezoelectric elements are manufactured separately in a high temperature ceramic firing process, a ceramic substrate is provided, having a surface with a plurality of electrodes thereon. A layer of dielectric material is formed on the substrate surface. Holes are formed in the dielectric material layer over the electrodes, defining cavities with metal pads at the bottoms. The individual preformed piezoelectric elements are then inserted into the holes; with one end of each element in contact with a corresponding one of the substrate electrodes. The holes are sized such that the piezoelectric elements are isolated from the dielectric layer. A ground plane conductor is then formed over the dielectric material layer and over the ends of the piezoelectric elements opposite the ends in contact with the piezoelectric elements, and is photolithographically patterned and may be etched to provide a "mesh" structure.