Abstract: A keyboard according to the present invention, which includes one or more keys and corresponding electromechanical converting elements, is characterized in that it includes a film construction (42) which includes an electret film with a bubble construction known as EMF by which said electromechanical converting elements corresponding to the keys are formed, and a solid, stiff cover plate (43) which covers the EMF construction (42) and in which an area (A-D) in the vicinity of each electromechanical converting element forms a key. In one embodiment of the present invention, a frame of the keyboard forms the cover plate and the EMF construction affixed behind the cover plate is covered with a sufficiently thick and stiff layer of plastic. The cover plate may be steel or aluminum, for example, and other materials such as plastic, glass or ceramic materials can be used. The thickness of the cover plate may be approximately 2 mm, for example.

Abstract: A plate material 1 and piezoelectric ceramics 2 are bonded together through an alloy layer 3 formed by an alloy forming reaction due to the mutual diffusion phenomena between a liquid metal including at least galium and the plate material 1 or the piezoelectric ceramics 2, or the mutual diffusion phenomena between the liquid metal and metal powder. The alloy layer 3 may include at least one or more of indium, tin and zinc and at least one or more of copper, silver, gold, and palladium. Further, a metal may be provided on at least one of the bonded surfaces of the plate material 1 and the piezoelectric ceramics 2. This metal may include one or more of copper, silver, gold, tin and palladum. In addition, a metal layer may be formed on the bonded surface 1a side of the plate material 1. Still further, an amorphous layer may be formed on at least one of the parts between the plate material 1 and the alloy layer 3, and between the piezoelectric ceramics 2 and the alloy layer 3.

Abstract: A SAW device comprising an inter-digital electrode capable of withstanding application of excessive electric power, while preventing an increase of insertion loss. The SAW device has an inter-digital electrode formed by alternating layers of aluminum films and conductive films, where the conductive films have an elastic constant greater than that of the aluminum films.

Abstract: A multi-layer piezoelectric transformer device includes first and second electroactive members having electrodes bonded to each of their opposing major faces; and a bonding layer disposed therebetween. The first and second electroactive members are polarized in a thickness direction, between their two major faces, such that when energized by an electric field the first and second electroactive members longitudinally strain. The first and second electroactive members are arranged such that deformation of one electroactive member results in corresponding deformation of the other electroactive member. The device provides substantial transformation ratios in which relatively high power may be transferred in relation to the size of the unit, operability over wide input and output frequency bandwidths, and electrical isolation of the voltage and current at the input to the device from the voltage and current at the output of the device.

Abstract: A piezoelectric ceramic transformer has a rectangular parallelopiped piezoelectric ceramic plate divided into a generator section and driving sections on both sides of the generator section, and first ring-shaped input electrodes and second ring-shaped input electrodes are alternately put on the rectangular parallelopiped piezoelectric ceramic plate at intervals so as to create electric field perfectly oriented in the longitudinal direction of the ceramic plate.

Abstract: A universal automotive alternator which comprises an alternator body, a front plate and an assemblage for attaching the front plate to the alternator body. A back plate is also provided. A structure is for securing the back plate to the alternator body. A facility is for mounting the front plate to a bracket on an engine. In some instances, a component is utilized for mounting the back plate to a bracket on the engine.

Abstract: A piezoelectric/electrostrictive actuator including a ceramic substrate, and at least one piezoelectric/electrostrictive actuator unit formed on at least a portion of at least one surface of the substrate, each piezoelectric/electrostrictive actuator unit having a first electrode film, a piezoelectric/electrostrictive film and a second electrode film which are laminated in the order of description, with the piezoelectric/electrostrictive actuator unit formed on the substrate by heat treatment.

Abstract: A bone inducing material comprising a piezoelectric porous membrane having through-holes of an average pore size of about 0.1 to 5 .mu.m is disclosed. When the bone inducing material according to the present invention is used, bone is rapidly regenerated, and new formation of bone occurs. The bone inducing material is particularly useful in the dental field, for example, for treatment of periodontal diseases by GTR method.

Abstract: A terminal for a piezoelectric device has a first electrode portion, a second electrode portion folded on the first electrode portion, projections on the first and second electrode portions, and further a vibration absorber between the first and second electrode portions. As the vibration absorber, oil, a non-volatile component of oil, silicone grease, polyamide resin, paper, an anticorrosive, a coating agent, silicone rubber, etc. may be used. Another terminal for a piezoelectric device has a sealant between the first electrode portion and the second electrode portion.

Abstract: A vibration wave driven motor having an electromechanical energy conversion member for generating a vibration wave in an elastic member. This conversion member has first and second surfaces opposite to each other, and first and second surfaces respectively formed on the first and second electrodes to receive an applied electrical signal. The first electrode is formed in a position such as to face one side of the elastic member and has an electrical signal input terminal provided on the second surface side of the conversion member. This input terminal and the first electrode are electrically connected by, for example, a conductor formed in a through hole. It is thereby possible to supply an electric current to each electrode with reliability while maintaining the conversion member and the elastic member in desired close contact with each other.

Abstract: A piezoelectric/electrostrictive actuator comprising a substrate, a plurality of electrodes in the form of strips formed on at least one surface of the substrate such that the electrode strips are spaced from each other in a direction parallel to the substrate surface, and a piezoelectric/electrostrictive portion which is disposed between the adjacent strips of the electrodes in the spacing direction, and in contact with the adjacent electrode strips, so that the piezoelectric/electrostrictive portion produces a flexural displacement or force due to at least the longitudinal mode of converse piezoelectric or electrostrictive effect upon application of a voltage between the adjacent electrode strips.

Abstract: An electrostrictive effect element has a laminated-structure formed by a plurality of electrostrictive ceramic members and a plurality of internal electrode conductive layers which are stacked alternatingly. The electrostrictive effect element has, on each of the opposite side surfaces of the laminated-structure, an external electrode conductive layer which is formed by a plurality of land conductors made of sintered-type conductive paste for interconnecting the exposed internal electrode conductive layers not covered by glass insulation layers, and a belt-like conductor made of resin hardening-type conductive paste for interconnecting the plurality of land conductors. Silver diffusion into the glass insulation layers can be avoided while maintaining low contact resistance between the external electrode conductive layer and the internal electrode conductive layers.

Abstract: A piezoelectric resonator (100) with an attenuated spurious response. The resonator (100) includes a piezoelectric crystal plate (102) having opposite surfaces (104, 106), electrodeS (108, 114) positioned in overlying relationship on each of the opposite surfaces (104, 106), the electrodes (108, 114) being substantially coextensive and opposite, and providing a primary frequency mode of operation and spurious modes upon suitable energization, and the electrodes (108, 114) having a grid-like structure (124) to provide a substantially uniform distribution of electrical charges over an electroded region (126).

Abstract: A piezoelectric/electrostrictive element is disclosed which includes at least one piezoelectric/electrostrictive portion each of which consists of a lower electrode film, a piezoelectric/electrostrictive film and an upper electrode film. In this element, at least the lower one of the electrode films has a surface roughness represented by maximum peak-to-valley roughness height Rmax. or Ry which is in a range of 3 .mu.m.about.14 .mu.m, and a surface roughness represented by centerline mean roughness Ra which is not larger than 2 .mu.m.

Abstract: A chemical sensor includes a piezoelectric support (1) capable of supporting a shear horizontal wave provided on its surface with an electrode (2,3). The sensor is characterized in that the surface of the piezoelectric support (1) including the region bearing the electrode (2,3) is covered by a layer of dielectric material (9) of thickness 0.5 to 20 microns. The piezoelectric support (1) is preferably a single crystal. The dielectric layer (1) may be of, for example, silicon dioxide or a suitable polymer, and preferably has a thickness of between 0.5 and 5 .mu.m.

Abstract: Monolithic, internally asymmetrically stress biased electrically active ceramic devices and a method for making same is disclosed. The first step in the method of the present invention is to fabricate a ceramic element having first and second opposing surfaces. Next, only the first surface is chemically reduced by heat treatment in a reducing atmosphere. This produces a concave shaped, internally asymmetrically stress biased ceramic element and an electrically conducting, chemically reduced layer on the first surface which serves as one of the electrodes of the device. Another electrode can be deposited on the second surface to complete the device. In another embodiment of the present invention two dome shaped ceramic devices can be placed together to form a completed clamshell structure or an accordion type structure. In a further embodiment, the clamshell or accordion type structures can be placed on top of one another.

Abstract: Disclosed is a multilayer piezoelectric element in which the anisotropic conductive layers are formed on two side surfaces, each surface opposing with each other, of the multilayer piezoelectric element that a plurality of the piezoelectric plates and the internal electrodes are alternately stacked and the conductive portions are alternately formed in the anisotropic conductive layer corresponding to the internal electrodes disposed on each side surface, thereby the internal electrodes and the external electrodes are electrically connected with each other on each side surface through the conductive portions.

Abstract: A piezoelectric lamination actuator is disclosed which is used as a driving source, such as for a printer head. In the actuator, a number of piezoelectric layers, each sandwiched between internal electrodes, are laminated with one on top of another by glue. A dielectric layer is glued on each end of the laminated piezoelectric body formed of piezoelectric layers, and thin-film external electrodes are formed on two diagonally opposite sides of the laminated piezoelectric body. One thin-film external electrode is connected to every second internal electrode, and the other thin-film external electrode is connected to the remaining internal electrodes. External electrodes are formed by sputtering or by thin metal straps, to reinforce the external electrodes and associated soldering joints.

Abstract: A sheet-form piezoelectric device having improved mechanical strengths as represented by an electrode peel strength while retaining flexibility and piezoelectric performances of a polymer-type piezoelectric device, is obtained by embedding a perforated sheet electrode into at least one surface layer of a polymer piezoelectric film treated with a solvent in advance. The sheet-form piezoelectric device may be wound or curved about a certain central axis to provide a tubular or curved piezoelectric device having wave-transmitting and/or -receiving characteristics suitable for wave-transmitting and/or -receiving devices, such as a hydrophone and microphone.

Abstract: A piezoelectric device has a piezoelectric element (2) with an electrically conductive surface and an electrical terminal (1) spaced from that surface with a resilient, compressible mass of electrically conductive material (9) held captive between the terminal (1) and that surface to form an electrical connection therebetween. Typically, the electrically conductive material (9) comprises filaments, such as brass wire wool, having at least a conductive surface layer and which are resilient in bending so that when compressed they tend to expand and maintain continuous physical and electrical contact with the adjacent restraining surfaces. The low inertia of the resilient filaments and their multiple contact with the adjacent surfaces helps provide the required continuous contact. Thus, the use of a conventional soldered connection to the piezoelectric element and the associated stress related mechanical failure problems or physical access problems are avoided.

Abstract: A piezoelectric bending transducer includes two piezoceramic layers each having two sides and electrodes on both of the sides. A graphite fiber layer is glued between the piezoceramic layers with an epoxy resin. The graphite fiber layer has a greater length than the two piezoceramic layers defining an exposed part of the graphite fiber layer. A copper foil is glued to the exposed part. The copper foil has an area for disposition of a solder contact. A process for producing a bending transducer includes placing a graphite fiber layer impregnated with incompletely hardened epoxy resin between two polarized piezoceramic layers. The graphite fiber layer is glued between the piezoceramic layers upon hardening of the epoxy resin. A copper foil is glued onto the graphite fiber layer, preferably simultaneously with the gluing of the two piezoceramic layers.

Abstract: A piezoelectric bimorph type actuator which, given a constant applied voltage, is capable of greater displacement without suffering from the problem of generating a smaller force of displacement or increasing the actuator size. The piezoelectric bimorph type actuator which is cantilevered, includes an electrode plate, a pair of piezoelectric plates provided on both sides of the electrode plate, and a voltage source for applying a voltage between each piezoelectric plate and the electrode plate so as to displace a free end thereof, wherein a ratio t.sub.2 /t.sub.1 between the thickness t.sub.2 of the electrode plate and the thickness t.sub.1 of each piezoelectric plate is set to be 0.42-1.11 times as much as a ratio E.sub.2 /E.sub.1 between the Young's modulus E.sub.2 of the electrode plate and the Young's modulus E.sub.1 of each piezoelectric plate.

Abstract: A quartz crystal resonator is utilized to effect evaluation of the viscoelastic characteristic of a film deposited on an electrode by an electrochemical reaction. The quartz crystal resonator is connected to a resonator characteristic measurement unit comprised of an oscillating circuit, a frequency counter, and an amplitude level meter. An electrochemical measurement unit in the form of a potentiostat is connected to a working electrode which comprises one of the electrodes of the resonator, to a reference electrode and to a counter electrode. The frequency counter, the amplitude level meter and the potentiostat are connected to a CPU. The resonator, reference electrode and counter electrode are all immersed in an electrolyte solution in an electrochemical cell.

Abstract: The description details a preferred embodiment of an improved large area ultrasonic transducer 70 capable of reducing the generation of adverse "edge effect" waves. The transducer has a thin piezoelectric wafer 72 that has a high area-to-thickness ratio of preferably between 30 and 300. A front electrode coating 84 is deposited on the front surface 74, over the front edge 77, along the side surface 82 and over the back edge 78 and onto a border of the back surface 76 to minimize the application of a voltage potential along the side surface.A voltage modifying layer 92 is placed on the back surface 76 along the back edge 78 for further minimizing the generation of "edge effect" waves. The layer 92 varies in thickness to progressively decrease the voltage applied to the back surface 76 from a large central area 79(a) to the back edge 78. The layer 92 is preferably composed of a non-piezoelectric dielectric material.

Abstract: A piezoelectric/electrostrictive element is disclosed which includes a ceramic substrate formed principally of partially or fully stabilized zirconia, a lower electrode formed on the ceramic substrate, a piezoelectric/electrostrictive layer formed on the lower electrode, and an upper electrode formed on the piezoelectric/electrostrictive layer. The element further includes an auxiliary electrode formed on the ceramic substrate, apart from the lower electrode, such that a portion of the auxiliary electrode is located between the piezoelectric/electrostrictive layer and the ceramic substrate. The auxiliary electrode is formed of an electrically conductive material which permits sufficiently good adhesion of the auxiliary electrode to the ceramic substrate and the piezoelectric/electrostrictive layer. The upper electrode extends between and is electrically connected to the piezoelectric/electrostrictive layer and the auxiliary electrode.

Abstract: An acoustic ink printer transducer comprising a piezoelectric layer positioned between two suitable electrode materials. Also, a method for obtaining second harmonic operations from an acoustic ink printer transducer to enable ejection of a number of different ink droplet sizes from the acoustic ink printer thereby facilitating grey scale printing.

Abstract: Multilayer piezoactuators are made by stacking and pressing alternating layers of piezoceramic material and interdigital electrode material. The electrode structure is provided with pressure protected boundary discontinuities which form areas in which electrodes edges do not make contact with the common electrical collectors of the piezoactuators and in which the piezoceramic layers are prevented from touching one another.

Abstract: In an overall stacked piezoelectric element, the material for the electrode was selected from aluminum, nickel and copper each alone or alloys based on aluminum, nickel or copper, and further the parts of the electrodes which contact with molding resin on the side face of the stacked body and the parts which have to be insulated from the lead-out terminals were subjected to an oxidation or nitriding treatment. As the result, an improved element was obtained which is of a high reliability, suited to low voltage operation and suffers no short-circuit of the electrodes even when water permeates to the side face of the stacked body during operation in a humid atmosphere.

Abstract: According to the present invention, there are provided a stack-type piezoelectric element constructed of a stacked body comprising plural layers of sintered piezoelectric ceramic material and electrodes which lie between the respective layers of the piezoelectric ceramic material, wherein said electrodes are formed of a material capable of diffusion-bonding with said piezoelectric ceramic material at a lower temperature than the sintering temperature of said ceramic material, a process for producing the same, and a stack-type piezoelectric device using said stack-type piezoelectric element.

Abstract: A piezoelectric ceramic actuator having a laminated body obtained by alternately laminating a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers in which at least one part of two adjacent ceramic layers, having the internal electrode sandwiched therebetween, are bonded to each other through particles of ceramic powder contained within the internal electrode. As a result of this structure, the bonding strength between the ceramic layer and the internal electrode can be greatly increased compared with conventional designs, thus improving the impact resistance of the actuator. The average particle size of the ceramic powder contained within the internal electrode ranges from one-third to one times (preferably from one-half to one times) the thickness of the internal electrode, and the mixing ratio of the ceramic powder ranges from 10 to 20 weight percent to electroconductive materials within the internal electrode.

Abstract: An energy coupling for piezo-electric crystals and mounting for the crystals wherein the crystal is flexibly edge mounted and isolated from a rigid holder and is backed by a flexible and compressible conductor to which selected frequency energy is transmitted having an adjustable compression plate therebehind for maintaining proper energy transmitting contact between the crystal and conductor for production of a collimated sound beam from the face of the crystal from a plurality of electrodes on the back face of the crystal. The system provides for energy transmission with no possibility of isolation at any frequency other than at the desired frequency of transmission.

Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.

Abstract: Interdigital transducers (3, 4) and reflectors (5, 6) are formed on a piezoelectric substrate (2) by an aluminum film. The aluminum film is crystallographically oriented in a constant direction, whereby stressmigration of the aluminum film is suppressed.

Abstract: A SAW device having a piezoelectric substrate and interleaved metal electrodes formed on the substrate, in which the formation of the electrodes on the substrate is carried out by sputtering. Further, the metal electrodes may contain an additive of Cu, Ti, Zn, Mg, Fe, Ni, Cr, Ga, Ge, Sn, Pd or Ta. The resulting SAW device is capable of dealing with high frequency electric signals of a larger amplitude, or higher power electric signals, as compared with the conventional SAW device.

Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.

Abstract: A surface accoustic wave device includes a substrate which is made up of single-crystalline dielectric member and a piezoelectric thin film epitaxially grown thereon. An aluminum electrode defining an interdigital electrode is formed along the interface between the dielectric member and the piezoelectric thin film. This aluminum electrode is formed of an aluminum film which is crystallographically oriented in a constant direction, whereby stressmigration of the aluminum electrode is suppressed, while enabling epitaxial growth of the piezoelectric thin film over the entire surface insert.

Abstract: A surface acoustic wave device having interdigitated transducers comprised of an improved metalization system including copper and titanium doped aluminum transducers. A method of producing the interdigitated transducers includes deposition of the metals on a quartz substrate and subsequent heat treatment. The metalization system provides SAW devices having improved long-term frequency stability, particularly when operated at high power levels. The surface acoustic wave device may be incorporated in a feedback loop of an amplifier to form an oscillator circuit.

Abstract: A piezoelectric laminate comprises a piezoelectric layer and an insulating substrate layer rigidly bonded thereto. During poling, conditions are established under which a poling potential is established at the boundary of the layers which insures that a substantial part of the poling voltage is dropped across the piezoelectric layer. The poling voltage is maintained for a period greater than the time constant under the poling conditions of the material to which the poling voltage is applied. In one embodiment, the poling conditions are achieved by substantially enhancing the conductivity of the substrate layer relative to that of the piezoelectric layer. In a second embodiment, an intermediate bond layer is selectively switched from a non-conductive to a conductive state in response to a selected stimulus so as to form an electrode for facilitating the application of a poling field directly across the piezoelectric layer.

Abstract: A piezoelectric element of laminate type comprising a plurality of films or thin sheets of piezoelectric material of the same size, each having an internal electrode formed on its entire surface, said films or sheets being laminated so that the end face of each internal electrode is exposed at the side of the laminate, wherein an insulating layer is formed by a photosensitive composition to electrically connect every second internal electrode.

Abstract: A solid state electronic device having a thin film of an Al (aluminum) alloy Li (lithium) on the surface of a substrate for a surface acoustic wave (SAW). Interdigital electrodes, electric wiring patterns and bonding pads are formed by the thin film of the Li-added Al alloy. This thin film suppresses migration which occurs when a high density current is supplied to the device or a large amplitude SAW is generated. The thin film, which provides a small loss and relatively low hardness, provides a desired power handling capability and high yield of wire bonding. The this film assures high endurance to failure of the device and sufficient life of the device.

Abstract: A surface acoustic wave device has its inter--digital transducers made of a 3--metal alloyed material consisting of aluminum, copper and magnesium.

Abstract: A piezoelectric switch including a casing for receiving an external mechanical force, a piezoelectric ceramic for sensing the external mechanical force received by the casing and converting the force to an electrical signal, the ceramic having one side connected to the casing and another side having both the positive and the negative poles, a conductive rubber connector disposed adjacent to and in contact with the ceramic for conducting the electrical signal and a printed circuit board disposed adjacent to and in contact with the conductive member for receiving and processing the conducted electrical signal received from the ceramic and for preventing any electrical signals from passing from the circuit board through the conductive member to the piezoelectric ceramic.

Abstract: A laminated piezoelectric transducer, comprising a laminate of a plurality of piezoelectric plates with paste electrodes inserted therebetween and bonding the plates together. Rows of metal extrusions are made by electroless plating onto the paste electrodes on the peripheral outer surface of the laminate. Each row of the metal extrusions is formed onto and electrically connected to alternate paste electrodes, so that by electrically connecting each row of the metal extrusions, the laminate of the piezoelectric plates is electrically connected in parallel. This laminated piezoelectric transducer allows the formation of the paste electrodes on the entire or at least substantially the entire main surfaces of the piezoelectric plates, and eliminates the need for the usual metal plate electrodes inserted between the piezoelectric plates.

Abstract: The elastic surface wave device is comprised of an inter-digital transducer, a multi-strip coupler or a hone type acoustic beam width compresser, and an output terminal which are formed on a piezo electric substrate. The inter-digital transducer can produce an elastic surface wave signal which has a predetermined delay time, an electrode width equal to and u band width BW equal to ##EQU1## The hone type acoustic beam width compresser can produce the mixed effect of non-linearity by transferring maximum energy in accordance with the proportion of the input acoustic beam width l.sub.1 and the output acoustic beam width l.sub.2 to increase the acoustic power density. The multi-strip coupler can filter low band frequencies by spatially integrating the electrical displacement of the elastic surface wave according to the electrode length of the output side.

Abstract: A method is described for making an electroconductive composite sheet electrode which is conformable and in which a slit-and-expanded or perforated nickel screen is embedded by heat and pressure, so that electrical leads can be easily and strongly attached to the nickel screen before or after integrally bonding a electroconductive sheet electrode to each side of at least one adjacent piezoelectric ceramic/polymer composite sheet electrode which is non-conductive. After poling, the resultant transducer has an increased combined transverse stiffness which increases the hydrostatic voltage coefficient, g.sub.h, as well as the overall hydrophone Figure of Merit.

Abstract: A piezoelectric sensing element is formed from bonding two piezoelectric layers with an intermediate metallic film. The intermediate metallic film is comprised of two separate films, which were sputtered onto the inner surfaces of the respective piezoelectric layers, which are then placed in contact with each other. The combination of piezoelectric layers and film is next heated at an elevated temperature for fusing the respective sputtered alloy films so that the piezoelectric layers are bonded into a piezo-pair sensor. The layers to be joined are chamfered so that the center electrode appears as a notch on the finished piezo-pair to allow a connection to the center electrode for poling and sensing.

Abstract: A transducer for a stringed musical instrument incorporating an electrically conductive ground plane, along with a plurality of piezoelectric transducers and a conductive strip. The ground plane, piezoelectric transducers and conductive strip are secured in an elongated unitary structure with the ground plane and conductive strip disposed on opposite sides of the transducers. A conductive shield made of paper with a conductive coating is disposed about the unitary structure and electrical leads connect to the ground plane and conductive strip, respectively.

Abstract: A piezoelectric vibrator comprises a mechanical vibrating member having, an aluminum layer formed on a surface of the vibrating member, and a piezoelectric transducer overlaying the aluminum layer.

Abstract: A piezoelectric sensitive element has elements for collecting charges appearing between the sides of the piezoelectric element. These elements include a flexible insulating strip having one the same face two distinct conductive layers each of which has an annular layer for contact with the piezoelectric sensitive element and connected by a connecting layer to a terminal layer. Application is to the detection of pinging in internal combustion engines.

Abstract: An embodiment of a non-contact electrical keyboard switch which completely resists EMI and eliminates cross-talk comprises a pair of electrically insulating substrates having rows and columns of openings therethrough. A poled piezoelectric PVDF film is adhered to each substrate over the openings. The films have silk-screened ground electrodes deposited on one surface and signal generating key electrodes deposited on the other surface in registration with the openings. Leads connecting individual rows of key electrodes on one film and individual columns of key electrodes on other film are disposed orthogonally. An insulating sheet separates the films which have their key electrode surfaces facing each other. Leads are connected to ground and/or suitable electrical connectors to provide the keyboard switch. Processes are disclosed for fabricating embodiments of the keyboard switch.