Abstract: A chip type piezoelectric device includes an element body formed of cofired ceramic material and having at least a pair of excitation electrodes opposed to each other with a portion of the element body interposed therebetween. At least the portion interposed between the excitation electrodes has piezoelectricity imparted thereto, whereby this portion serves as a vibrating portion. Of the pair of excitation electrodes at least one excitation electrode is positioned in the interior of the element body, and the element body is formed with a cavity only on the side of this interiorly positioned excitation electrode away from the vibrating portion.

Abstract: For the purpose of utilizing the characteristic in a vibration energy entrapping mode of a higher order symmetric or asymmetric mode vibration generated when a piezoelectric resonator is excited, there are provided a portion having a cutoff frequency f.sub.2 about an energy entrapping portion having a cutoff frequency f.sub.1 for strongly exciting a higher order symmetric or asymmetric mode vibration and at least one energy absorbing portion having a cutoff frequency f.sub.3 (at least f.sub.1 and f.sub.3 <f.sub.2). The size of the energy entrapping portion (electrode), amount of plateback (f.sub.2 -f.sub.1)/f.sub.

Abstract: A dual-coupled resonator crystal is fine-tuned by frequency balancing the input and output resonators and thereafter plating a coupling adjust spot on the grounded side shadowing the unelectroded region of the front side of the crystal to produce a change in synchronous peak separation frequency. Thereafter, the front side electrodes are sequentially plated to bring plateback and synchronous peak separation frequency to their target values. Interim adjustments in synchronous peak separation frequency may be made during the tuning process to compensate for misalignment of the plating elements.

Abstract: A system is described which comprises many quartz resonators, all formed on the same quartz substrate. The method of fabrication ensures that all the resonators are mechanically and electrically isolated from each other. The oscillation frequencies of the resonators may be individually adjusted to different desired values during fabrication. Since the deviation from the optimum angle of cut is the same for all the resonators because they are all on the same substrate, all the resonators have the same temperature coefficient (change of frequency per degree change in temperature). Mounting the electronic circuitry on the quartz substrate simplifies the interconnections between the resonators and the circuitry, and reduces the size of the resulting device.

Abstract: A piezoelelectric transducer usable preferably as a high-frequency ultrasonic probe for diagnostic inspection and the process for preparation thereof are disclosed.The piezoelectric transducer comprises a piezoelectric material layer, a pair of electrode layers formed respectively on the opposite surfaces of said piezoelectric material layer and for applying electric load across the piezoelectric material layer to thereby generate acoustic oscillation or for measuring electric energy generated due to the acoustic oscillation of the piezoelectric material layer, and an acoustic matching section containing at least one quarter-wave matching layer and formed on one of the electrode layers. The acoustic matching section includes an elelctric conductive layer therein.The acoustic matching section is formed by electro deposition, preferably by the electro painting method or electrophoretic method.The ultrasonic probe can be prepared of a frequency band higher than 7.

Abstract: Piezo-electric assembly having a piezo-electric resonator of trapped energy type assembled within a forming case. A bulkhead within the case prevents manufacturing defects due to internal spreading of conductive paste, regardless of variations in the coating amount of the conductive paste in mass production or variations in the mount pressure. Constant clearance exists between the internal connecting portions of the external terminals and the draw-out electrode (input/output) electrodes of the resonator, so that any variation in the conductive paste coating amount or the mount pressure is compensated.

Abstract: The disclosure relates to a small volume bulk acoustic channelizer, which does not utilize light and thereby avoids the shortcomings of light-related channelizers including limited dynamic range and poor response to short pulses. The device is essentially a bulk acoustic analogue of an optical spectroscope.

Abstract: A method of fabricating a high-frequency piezoelectric resonator includes the steps of (a) forming a region of reduced thickness in a central portion of a quartz disk, a step zone being formed at the transition between the thinned region and the non-thinned region; (b) depositing a conductive tongue on the step so as to extend over a portion of the non-thinned region and over a portion of the thinned region; (c) mounting two lead attachments on the disk; and (d) depositing first and second electrodes on the disc, each electrode coupled to a respective one of the lead attachments, a portion of the first electrode being deposited on the conductive tongue.

Abstract: A trapped-energy mode resonator is obtained by forming conductive patterns on sheets of ceramic material and then laminating the ceramic material to obtain a resonator wherein a pair of central electrodes oppose one another through a central portion of the ceramic and peripheral electrodes oppose one another through peripheral portions of the ceramic, with the central and peripheral electrodes not overlapping one another. The distance between the central electrodes is shorter than the distance between the peripheral electrodes, with the central electrodes being embedded within the ceramic and the peripheral electrodes being either embedded within or formed on the surface of the ceramic.

Abstract: An improved method of adjusting piezoelectric devices to frequency by particularized laser trimming is disclosed. The laser removes a single contiguous area in the center of the electrodes to appropriately increase the individual resonator frequency without significantly degrading the filter "Q". In an AT-cut monolithic crystal filter, the particularized laser trimmed area can be positioned such on the face of the electrodes to simultaneously control frequency and bandwidth. This method can be substituted for the more cumbersome process of frequency adjustment by vapor deposition to provide a rapid inexpensive technique for monolithic crystal filter manufacture.

Abstract: An improvement in piezoelectric crystal resonators using lateral excitation whereby energy of vibration trapped in a region between the electrodes is provided by the inclusion of recessed electrodes adjacent a relatively raised piezoelectric region on at least one major face or surface of the crystal. The recessed electrodes oppose one another in either a horizontal or a vertical direction to generate a lateral field in the body of the crystal upon excitation. Additionally, curved edge interfaces are provided between the recessed electrodes and the piezoelectric crystal material to reduce field gradients. Tapered electrodes which have the effect of increasing the energy trapping in the gap between the electrodes are also disclosed.

Abstract: A resonator (1) is described for vibrating in a thickness-shear mode and has auxiliary electrodes (7f, 8d) between the zone of its main excitation electrodes (3, 4) and the zone of its connection terminals (5, 6) to generate an auxiliary vibration in opposition of phase with respect to the main vibration.The presence of the auxiliary electrodes (7f, 8d) improves notably the quality factor of the resonator.

Abstract: Piezoelectric ceramic compositions comprising a principal component, ##EQU1## and manganese contained therein as an additive in the amount of 0.1 to 2.0 wt % of MnO.sub.2 with respect to the weight of 1 mol of the principal component. The piezoelectric ceramic compositions are suitable for use for pyroelectric devices, piezoelectric vibrators, resonators, oscillators, ceramic filters, surface acoustic wave filters and so on.

Abstract: A piezoelectric resonating device utilizes double thickness vibration mode of the energy-trapped type and comprises a piezoelectric plate, input and output electrodes disposed at one surface of the piezoelectric plate and a common ground electrode disposed at the other surface of the plate. The common ground electrode is disposed to face against the input and output electrodes and the input and output electrodes are formed by a plurality of electrode segments. A plurality of piezoelectric resonating segments are coupled together each comprising the respective electrode segments and the common ground electrode.

Abstract: A liquid sensor mounted on the side wall of a liquid tank for detecting the existence of liquid in the tank. The sensor includes an element which generates a vibration in the direction of its thickness, of energy-trapped type for detecting the existence of liquid. The element consists of electrodes provided on both sides of a piezo-electric substrate, one side of the element for contacting the liquid in the tank being covered with a liquid-proof coating. The existence of liquid is detected from the change in resonance impedance or antiresonance impedance resulting from the liquid contact.

Abstract: A method of fabricating an acoustic wave resonator wherein all processing steps are accomplished from a single side of said substrate. The method involves deposition of a multi-layered Al/AlN structure on a GaAs substrate followed by a series of fabrication steps to define a resonator from said composite. The resulting resonator comprises an AlN layer between two Al layers and another layer of AlN on an exterior of one of said Al layers.

Abstract: The disclosed apparatus of the invention operates to generate and direct ultrasound over predetermined regions of a body, such as a programmed sequence of target points. A plurality of side-by-side tapered piezoelectric transducer elements are provided. Means are provided for energizing the transducer elements with electrical energy having a variable frequency. The frequency of the electrical energy is varied to change the direction of the ultrasound produced by the transducer elements. In the preferred embodiment of the invention, a processor is responsive to a coordinate of an input target point for controlling the variation of frequency. In one form of the invention, means are provided for varying the relative phases of the electrical energy applied to the transducer elements. In this form of the invention, the processor means is also responsive to at least another coordinate of the input target point for controlling the variation of the relative phases.

Abstract: A frequency synthesizer is provided that is capable of supplying a plurality of accurate frequencies. The frequency synthesizer comprises a resonator matrix including a plurality of resonators embedded in a single monolithic piece of piezoelectric crystal. The resonators are arranged in rectangular row and column configuration including m rows and n columns. Each of the resonators is separated from its neighboring resonators by distances such that the resonant energies do not overlap. Each of the rows of resonators bears a metallic electrode stripe for that row and each of the columns of resonators bears a metallic electrode stripe for that column, the electrodes row stripes being positioned on the top surface of the crystal and the electrode column stripes being positioned on the bottom surface of the crystal. The areas of overlap of the row and column stripes are registered with the central portions of the embedded resonators.

Abstract: The high-frequency piezoelectric resonator comprises a quartz plate or disk having a region of reduced thickness which forms a diaphragm and is joined to the remainder of the plate or disk by means of a zone forming a step. A conductive electrode extends from the exterior of the disk or plate to the center of the thinned region and is provided with a conductive tongue constituted by a metallic film-layer of controlled thickness and disposed in the stepped zone. The method involves formation of the disk or plate by ion machining whereas the electrodes and the conductive tongue are formed by the sputtering technique.

Abstract: An improved piezoelectric ceramic resonator in which spurious vibration other than that in a longitudinal direction of a piezoelectric ceramic plate is suppressed. The directions of polarization of the rectangular piezoelectric ceramic plate at opposite sides of a concave groove provided in the piezoelectric ceramic plate are different from each other, and are unequal in magnitude. A portion of the plate between the oppositely polarized portions is not polarized in any predetermined direction. The resulting arrangement improves a spurious characteristic of the piezoelectric ceramic resonator, and also rectifies an imbalance in selectivity characteristic between a high frequency side and a low frequency side, when the resonator is used in an electrical filter.

Abstract: A method of fabricating an acoustic wave resonator wherein all processing steps are accomplished from a single side of said substrate. The method involves deposition of a multi-layered Al/AlN structure on a GaAs substrate followed by a series of fabrication steps to define a resonator from said composite. The resulting resonator comprises an AlN layer between two Al layers and another layer of AlN on an exterior of one of said Al layers.

Abstract: A broad bandwidth electro-mechanical transducer is shaped into a wedge of varying thickness, with a plurality of PZT elements or sheets embedded in an inactive polymer. The transducer is driven at frequencies corresponding to resonance of the thickness dimensions. The piezoelectric elements with different thicknesses are decoupled mechanically from one another using an inactive polymer of low Q so as to prevent interference.

Abstract: A chip-like piezoelectric vibrator component is disclosed. The component includes an axially elongated case made of an insulating material, in which an elongated piezoelectric vibrator element is housed. The piezoelectric vibrator element comprises vibrator electrodes formed on opposite main surfaces of a piezoelectric plate, wherein energy is trapped only in the longitudinal direction, whereby thickness sliding vibration is caused. Conductive terminals or caps are fitted into openings at both ends of the case and these are electrically connected to electrodes extending to both ends of the element. Concavities are formed on the conductive terminals or caps at the inner side of the case so that the element may be positioned and held by the concavities, whereby a spacing is secured between the vibrating electrode portions of the element and the inner wall of the case.

Abstract: A trapped energy piezoelectric resonator for oscillator and multiple resonator applications has a piezoelectric substrate with electrodes disposed on each of its major surfaces. These electrodes are further comprised of a plurality of electrically interconnected and acoustically coupled sub-electrodes. The resonant frequency of these resonators may be controlled by varying the separation and, therefore, the acoustic coupling between the sub-electrodes. This resonator may be used in the feedback loop of an oscillator circuit as the frequency determining element. It may also be used to provide a resonator on a substrate carrying resonators of significantly different frequency.

Abstract: A piezoelectric device comprising a housing that contains a piezoelectric body bearing aluminum film electrodes. The exposed surfaces of the electrodes bear a passivating layer of amorphous aluminum oxide formed by heating the electrodes at a temperature between 250.degree. and 550.degree. C. in an atmosphere containing free oxygen.

Abstract: A low-profile crystal package wherein the wire bonding operation from the electrode pattern of the crystal plate to the terminal posts may be accomplished without fear of fracture of the crystal plate itself. The crystal blank is positioned on a support member which in turn initially sits on a ring of indium. In this position, the crystal blank is not in contact with the split center support post whose top surface is covered with indium paste, and is supported around its periphery during wire bonding. When all the wire bonding operations are effectuated, the assembly is subjected to sufficient heat wherein the indium material will melt, which will cause the support member to be drawn downward, thereby resulting in the crystal plate being supported and fastened only by the center supports, with the periphery of the crystal plate being free to vibrate with no extraneous dampened support.

Abstract: A symmetrical two pole monolithic crystal filter is combined with appropriate value fixed capacitors and cascaded with other similar filter elements to provide a high order filter with symmetrical transmission zeros and low passband ripple. The filter includes a piezoelectric resonating element having first and second opposite sides with first and second pairs of electrodes thereon. A first capacitor is coupled to an electrode of the first pair located on the first side and a second capacitor is coupled to an electrode of the second pair of the electrodes located on the first side. A shunting capacitor is used between the electrodes of the first and second pairs located on the first side. A fourth capacitor is coupled from both of the first and second electrodes located on the second side.

Abstract: An ultrasonic image device such as may be used in a holography system or scanning system and having a piezoelectric transducer in which the conversion efficiency and phase are substantially constant over a wide frequency range. A piezoelectric sheet 5 .mu.m to 1000 .mu.m thick is used for a piezoelectric element. The piezoelectric sheet is constructed of a macromolecular material including polymers and copolymers of polar monomers. A high frequency signal input device applies to the electrodes coupled to the piezoelectric sheet high frequency signals of different frequencies in a range around a fundamental resonance of the piezoelectric sheet of .+-.10 to .+-.70% of the fundamental resonance frequency.

Abstract: A piezoelectric cone-type speaker having a multiple structure in which a plurality of piezoelectric elements and speaker diaphragms individually coupled to them are coaxially or multi-axially arranged. It has a wide frequency range. A cushioning member is interposed between one diaphragm and another so that each element is isolated from the vibrations of another element.

Abstract: A thickness mode piezoelectric ceramic resonator is connected in series with a ceramic capacitor to form a piezoelectric ceramic resonator unit. When the ceramic capacitor has a capacitance Ca and the resonator is associated with a damped capacitor having a capacitance Co, these capacitances are related to each other by a relationship,Co.ltoreq.Ca.ltoreq.30 Co.

Abstract: A driving electrode on a surface of the piezoelectric vibrator in accordance with the present invention has a blank which is narrow at the center portion and wide at the right and left portions on the Z axis. And the driving electrode is the shape easy to operate in the fundamental main vibration, and hard to operate in the spurious vibration. Thus the piezoelectric vibrator operates efficiently in the fundamental main vibration.

Abstract: A piezoelectric vibrator includes an elongated piezoelectric plate deposited with electrodes for effecting mechanical vibration in the piezoelectric plate. A damper is deposited at each of opposite ends of the elongated piezoelectric plate so as to reduce the size of the piezoelectric plate.

Abstract: A piezoelectric resonator of a width-extensional mode vibratory-energy trapping type having a rectangular piezoelectric plate of a width corresponding to a desired resonance frequency. Peripheral electrodes are deposited apart from one another in its lengthwise direction to cover over the width of opposite end portions of the piezoelectric plate in order to lower the cut-off frequency of the opposite end portions of the piezoelectric plate in comparison with the intervening central portion of the plate, so that the width-extensional mode vibratory energy may be trapped or confined within the central portion of the piezoelectric plate. The resonator can be supported and are connected to lead wires at peripheral electrodes.

Abstract: A thickness shear type piezoelectric vibrator comprises a quartz crystal plate of uniform thickness having a rectangular vibrating portion and integral rectangular supporting portions of less width extending from opposite ends of the vibrating portion. Electrodes of conducting material have elongated rectangular active portions on obverse and reverse surfaces of the vibrating portions of the plate. The electrode on the obverse surface of the plate has an integral lead portion extending along the obverse surface of only one of the supporting portions. The electrode on the reverse surface of the plate has an integral lead portion extending along the reverse surface of the other only of the supporting portions so that an electric field is applied by the electrodes only to the vibrating portion of the plate and not to the supporting portions.

Abstract: An ultrasonic wave transducer is formed from a body of piezoelectric material having nonuniform thickness. Each location on the transducer is resonant at a different frequency according to the thickness at that point. By changing the frequency of the applied excitation signal, the origin and direction of the radiation can be altered.

Abstract: A contour vibration mode piezoelectric resonator has a vibrating portion and at least one supporting portion integrally connected to the vibrating portion by way of a bridge portion. The supporting portion comprises a resilient portion directly connected to the vibrating portion, an attenuation portion integrally connected to the resilient portion and which is insubstantially displaced by vibration during use and a fixing portion fixable on a supporting member and which is either integrally connected to or forms a part of the attenuation portion.

Abstract: A two-pole monolithic crystal filter is described that includes grounded strip electrodes between input and output electrodes. The grounded strip electrodes have a higher resonating frequency than the input and output electrodes and also provide increased acoustical coupling and lower inter-electrode capacitance between the input and output electrodes, while having little or no effect on the midband electrical characteristics of the filter. Because of the increased coupling, the input and output electrodes can be spaced further apart than heretofore possible in prior monolithic crystal filters. Moreover, further increases in the acoustical coupling can be achieved by arranging a plurality of strip electrodes between the input and output electrodes. The inventive monolithic crystal filter can be advantageously utilized for filtering the IF signal developed in the IF portion of an FM radio receiver.

Abstract: A wafer of piezoelectric material is provided with electrodes on opposite surfaces thereof. Frequency fine tuning of such resonators is accomplished by relatively thin film of metal applied over the surface of at least one electrode and the adjacent non-electroded wafer material. The metal film is of such small maximum thickness that it functions as a quasi-insulator and is extremely stable over prolonged operating conditions so that the resonator parameters remain constant.

Abstract: The resonator according to the invention comprises at least one quartz crystal in the form of a rectangular thin plate, of which the length l is directed along an axis X', the width w along an axis Y' and the thickness t along an axis Z', and which vibrates in a contour mode. The axis Z' is situated in the plane of the electrical axis X and optical axis Z of the crystal and forms with the axis Z an angle .phi. such that16.degree.<.phi.<36.degree.and the axis Y' forms with the mechanical axis Y of the crystal an angle .theta. such that10.degree.<.theta.<30.degree.This resonator presents a zero temperature coefficient of the first order and is not dependent to any critical extent on the dimensional ratio between the sides w and l of the plate; the temperature coefficients of higher order are very small. The piezo-electric coupling is such that the optimized mode of oscillation is the only one excited in practice.

Abstract: A crystal plate is mounted on a pedestal area of an inverted bridge structure positioned within a depressed area of a crystal carrier. The plate is supported on the upper surface of the carrier until the wire bonding process is complete, then the ends of the bridge are forced down against support pins on the carrier and are welded into place. As the ends of the bridge are forced down, the center portion of the bridge is raised, elevating the crystal plate above the carrier surface for free vibration.

Abstract: A crystal is mounted on a low, centrally located pedestal. Connections to the lower side of the crystal are made by way of conductive areas on the pedestal. Multiple wiring connections are made at the edges of the crystal by allowing the bonding tool to depress the edge of the crystal so that the crystal bonding pad is supported by the base structure only during the bonding process, then released thereafter to allow free vibration of the crystal plate. Complex circuitry, possibly involving more than one frequency can thus be put onto one plate.

Abstract: The vibrating element comprises a pair of exciting electrodes having opposing effective portions formed on the opposing major surfaces of a piezoelectric plate, and vibration adjusting members disposed on at least one of the exciting electrodes. The vibration adjusting members are made of the same material as the exciting electrodes and do not project beyond the contour of the effective portions in the direction of propagation of the vibration energy of the vibration but project in a direction perpendicular to the direction of propagation.

Abstract: A piezoelectric resonator assembly comprises a single integral plate which is cut to form a peripheral region for supporting a resonator, a central resonating region for resonating in the longitudinal mode, surface-shear mode, or bending mode, and at least two oppositely positioned arms for fastening the peripheral region to the central region at opposite points on the central resonating region. The arms are positioned at nodal zones of the central resonating region. There is a single gap between the peripheral region and the central resonating region at each position about the central resonating region except at the positions of the arms. The entire upper and lower surfaces of the plate are continuous and have metal plates formed thereon for forming the excitation electrodes of the central resonating region. The metallized plates are attached to leads at the peripheral region.

Abstract: A fluid pessure transducer comprises a plate-like crystal. The pressure gives rise to a force which is applied by two seatings situated by opposing edges of a crystal in a direction generally along the face of the crystal. The change in oscillating frequencies of a part of the crystal provides a measure of the force and hence the fluid pressure.In the past a second matched crystal has been employed to provide compensation for inaccuracy brought about by undesired frequency deviation due to ambient temperature change of the instrument. The present invention consists of a single crystal having on it two oscillating areas simulating the behaviour of the original pair of crystals. The single crystal facilitates manufacture of the device and improves the accuracy of the instrument.

Abstract: Three electrode pairs are formed on a monolithic piezoelectric element which exhibits anisotropic properties with respect to its X and Z axes. The electrodes of each pair are located on opposite sides of the piezoelectric element, with all electrodes being of predetermined dimensions. The first and second electrode pairs are aligned on the X axes at a predetermined spacing therebetween. The second and third electrode pair are aligned on the Z axis, also at a predetermined spacing.In circuit operation, a signal to be processed is coupled to the first electrode pair and extracted from the third electrode pair, with the electrodes of the second pair shorted together. In this manner, the resonator displays a three pole passband characteristic having excellent spur suppression.

Abstract: A piezoelectric monolithic crystal filter operating in the trapped energy mode and having a capacitor plated on the piezoelectric wafer within energy coupling distance of the main electrodes has its output response improved by trapping wave energy, at the frequencies of the main electrodes, engendered by the capacitor and conducting such energy to the edges of the piezoelectric wafer where it is dissipated. Such energy is therefore not coupled into the filter structure and does not appear as an undesirable response.

Abstract: A piezo electric resonator member is cut from a quartz crystal in a rotated -orientation and arranged for vibration in a thickness shear mode, the member being in the form of a bar elongated along either the X-axis or the Z'-axis having rectangular cross sections in planes parallel respectively to the XZ'- and Y'Z'-planes or XZ'- and XY'-planes. It is provided with metallized layers to serve as electrodes confined to a central zone of the surfaces running in the same direction as the XZ'-plane. The ends of the bar serve as support points.

Abstract: This disclosure relates to improved piezoelectric quartz crystal products preferably used in quartz crystal filter and resonator applications, and fabrication methods therefor. Various embodiments are disclosed including a substantially circular, a square, and a rectangular quartz crystal product wherein each one contains a single triangular shaped electrode located on each of the two sides thereof in an overlapping arrangement. Other embodiments disclosed include a substantially circular, a square, and a rectangular quartz crystal product wherein each one contains multiple electrodes such as two spaced apart triangular shaped electrodes located on each side of the two sides thereof in an overlapping arrangement.

Abstract: A transducer array comprising a large number of separated sets of electrodes plated on a single piezoelectric plate of uniform thickness is described. Each set of electrodes is made to act essentially independently by placing them sufficiently far apart and employing an essentially trapped energy mode.

Abstract: A thickness shear resonator used as an overtone quartz crystal for a quartz stabilized oscillator which has an operating frequency in the MHz range that has an excitation electrode on each of its plane parallel surfaces running in the x, z' plane and where the thickness of the vibrator in the y' direction is determined by the distance of these surfaces from one another wherein the vibrator presents a dimensional ratio between its dimensions measured in the z' direction and its thickness which is determined by a fundamental quartz crystal frequency having a value of 1/3 of the operating frequency, thus, resulting in an oscillator which is not sensitive to influences from associated oscillating components.