Abstract: A multi-pole monolithic crystal filter (100) having at least three asymmetrically acoustically coupled resonators (104) on a piezoelectric blank (102) to provide an improved phase response (302). The resonators (104) are positioned substantially in inverse proportion to predetermined ladder network coupling coefficients to achieve an improved phase response filter. The ladder network coupling coefficients are selected from designs including Bessel, Gaussian, linear phase and equiripple models. In this way, a predetermined improved phase response (302) is obtained monolithically without discrete interstage tuning components.

Abstract: A resonant acoustic isolator supports a thin film acoustic resonator comprising a layer of piezoelectric material having top and bottom electrical contacts. The resonant acoustic isolator comprises at least one pair of layers of materials having different acoustic impedances. The isolator materials are deposited in alternating layers of high and low impedance material, with each layer having a thickness of 1/4 acoustic wavelength at resonant frequency. Silicon dioxide (SiO.sub.2) is preferred for the low impedance material because it is ubiquitous in the semiconductor industry, it has relatively low acoustic impedance with very low intrinsic acoustic loss, and it can be deposited using a variety of convenient methods. Hafnium oxide (HfO.sub.2) is preferred for the high acoustic impedance material because it can be deposited by evaporation to form a hard, dense dielectric having a relatively high acoustic impedance. Deposition of an entire stack of alternating SiO.sub.2 and HfO.sub.

Abstract: A ladder-type filter having a circuit structure obtained by connecting a plurality of series resonators and a plurality of parallel resonators with each other. At least one plate type series resonator and at least one plate type parallel resonator are stacked with each other. At least one of the series and parallel resonators is an energy trap type piezo-resonator having a plate type piezoelectric vibrating part, a support part which is coupled to the piezoelectric vibrating part, and a holding part which is coupled to the support part.

Abstract: An ultrasonic probe for coupling acoustic signals between the probe and a medium is provided. The ultrasonic probe has a piezoelectric element having a plurality of piezoelectric layers each having a different acoustic impedance. The piezoelectric layers are stacked in progressive order of acoustic impedance such that the layer with the acoustic impedance nearest to that of the medium is proximate the medium. At least one of said piezoelectric layers is made of piezoelectric composite material. The ultrasonic probe further has an electrode means for electrically coupling the piezoelectric layers to a voltage source for applying an oscillation voltage potential to each piezoelectric layer. The probe further has a control means for controlling the polarization of at least one of the piezoelectric layers.

Abstract: A warning module for use with a motor vehicle having multiple sensor inputs and multiple sensor outputs. The inputs are coupled to sensing circuits for monitoring a condition such as engine temperature. The outputs are coupled to one or more light bulbs or other visual indicators which are activated at a lamp flash frequency. A variable frequency oscillator activates an audible output device, preferably a piezoelectric buzzer. The light output levels are diminished for nighttime use. A plastic housing supports a piezo-electric transducer and reverberation plate and achieves a high sound output.

Abstract: A method of forming a transducer device having integral transducer and impedance matching portions includes forming grooves partially through a thickness of a piezoelectric member. A groove volume fraction at the impedance matching portion controls the electrical impedance. The impedance matching portion may be at either or both of the front and rear surfaces of the transducer portion, which generates acoustic wave energy in response to application of a drive signal. The drive signal is introduced by electrodes. In one embodiment, the electrode at the impedance matching portion extends into the grooves, but preferably a filler material is selected and deposited to allow use of a planar electrode. An alternative embodiment to fabricating the transducer device is to assemble piezoelectric material. For example, an integral transducer and impedance matching portions may be formed by using molding techniques or by stacking dimensionally different thin piezoelectric layers.

Abstract: A packaged piezoelectric oscillator is provided which comprises an insulating package body, a piezoelectric element, and a lid member. The package body has an upwardly open housing groove which has a bottom surface formed with oscillator electrodes at both ends of the housing groove. The package body is externally formed with first to third electrodes spaced from each other. The first and second electrodes extend into the housing groove for electrical connection to the respective oscillator electrodes, whereas the third electrode is located between the first and second electrodes. The piezoelectric element is fixedly received in the housing groove of the insulating package body and held in electrical conduction with the respective oscillator electrodes. The lid member is attached to the package body to close the housing groove. The lid member has a lower surface formed with first to third capacitor electrodes in electrical conduction with the first to third lead electrodes, respectively.

Abstract: A piezoelectric resonator (10) with an attenuated spurious response. The resonator (10) includes a piezoelectric crystal plate (12) having opposite surfaces (14, 16), an electrode (18, 24) positioned and overlying relationship on each of the opposite surfaces (14, 16), the electrodes (18, 24) being substantially coextensive and opposite, and providing a primary frequency mode of operation and spurious modes upon suitable energization, and a number of mass loading structures (34) on at least one of the surfaces (14, 16) substantially surrounding at least one of the electrodes (18, 24).

Abstract: First and second grooves (15, 16) are formed in upper and lower surfaces of a piezoelectric ceramic plate (12), which is polarized in a direction P parallel to its major surfaces, respectively. A resonance part is formed between the first and second grooves (15, 16), so that first and second resonance electrodes (13, 14) which are provided on the upper and lower surfaces of the piezoelectric ceramic plate (12) respectively are opposed to each other through the piezoelectric ceramic plate (12). In this energy trap type piezo-resonator utilizing a thickness shear mode, the resonance part has a pair of rectangular side surfaces, and the first and second grooves (15, 16) are so formed that a ratio b/a is in a range of .+-.10% from the following value:b/a=n(0.3.sigma.+1.48) (1)assuming that b and a represent lengths of longer and shorter sides of the rectangular side surfaces of the piezoelectric body respectively, .sigma.

Abstract: An ultrasound therapy system and method for providing therapeutic treatment to tissues using multiple, user-selectable frequencies generated from a single applicator sound head. The multi-frequency ultrasound therapy system and method includes a generator/control unit having a microprocessor for controlling and monitoring the generation and output of ultrasonic energy. A precision oscillator is connected to the microprocessor, and wave shaping circuitry is also provided to generate a wave-form for amplification by an output amplifier. The amplified high frequency wave-form is supplied to and drives an applicator sound head at an appropriate frequency for producing the desired therapeutic ultrasonic waves for treatment. Bonded to a cup member and positioned within the applicator sound head is a transducer crystal which converts high frequency wave-forms into mechanical (acoustic) vibrations, thus producing thermal energy in the form of heat for penetration into tissues under treatment.

Abstract: A piezoresonator which has, on a piezoelectric substrate, a plurality of oscillation sections and a coupling capacitor section for electrically connecting the oscillation sections with each other. The piezoelectric substrate is polarized, while the portion holding the coupling capacitor section is partly left unpolarized. Alternatively, the piezoelectric substrate is entirely polarized such that the portion holding the coupling capacitor section has a lower intensity of polarization than the rest of the substrate. The polarization is carried out, for example, in the following process: first, a direct voltage is applied to the entire piezoelectric substrate so as to polarize the substrate entirely with a high intensity; and then, a direct voltage with the inverse polarity of the former direct current is applied only to the portion holding the coupling capacitor section so as to lower the intensity of polarization of the portion.

Abstract: Disclosed is a thin film voltage-tuned semiconductor bulk acoustic resonator (SBAR). A piezoelectric film is positioned between a first electrode and a second electrode and positioned adjacent a semiconductor substrate containing a via hole. A variable voltage source applies a DC bias voltage to the electrodes which causes an electric field to be created between the electrodes within the piezoelectric film. The resulting electric field causes the piezoelectric film to resonate at a frequency different than its unbiased resonant frequency. By adjusting the variable voltage source to change the DC bias voltage, the resonant frequency from the thin film semiconductor bulk acoustic resonator (SBAR) can be varied.

Abstract: A piezoelectric-resonance device comprising a piezoelectric ceramic body, a pair of excitation electrodes provided so as to be opposed to each other with the piezoelectric ceramic body interposed therebetween, and connecting conductive portions connecting the excitation electrodes and side edges of the piezoelectric ceramic material, a portion, which is interposed between the excitation electrodes, of the piezoelectric ceramic body being polarized in the opposite direction to the direction of polarization of the other portion thereof.

Abstract: A piezoelectric ceramic transformer includes a piezoelectric plate, a pair of driving sections, and a power generating section. The piezoelectric plate is made of a piezoelectric ceramic material and has a long plate-like structure. The pair of driving sections are arranged at two end portions of the piezoelectric plate and formed by alternately stacking a plurality of piezoelectric ceramic layers polarized in a direction of thickness of the piezoelectric plate and first internal electrodes, and cause longitudinal vibration by a driving voltage applied to first and second input terminals. The power generating section is arranged at a central portion of the piezoelectric plate in a lengthwise direction thereof and polarized in the lengthwise direction of the piezoelectric plate, and generates an output voltage at a first output terminal by the longitudinal vibration transmitted from the driving sections.

Abstract: A tunable ultrasonic probe includes a body of a first piezoelectric material acoustically coupled in series with a body of a second piezoelectric material. The second piezoelectric material has a Curie temperature that is substantially different than that of the first piezoelectric material. Preferably, the first piezoelectric material is a conventional piezoelectric ceramic, such as lead zirconate titanate, while the second piezoelectric material is a relaxor ferroelectric ceramic, such as lead magnesium niobate. At an operating temperature of the probe, the first piezoelectric material has a fixed polarization. In contrast, the second piezoelectric material has a polarization that is variable relative to the fixed polarization of the first piezoelectric material. A preferred novel arrangement of electrodes electrically couples the bodies in parallel with one another. An oscillating voltage for exciting the acoustic signals in the probe is coupled with the electrodes.

Abstract: An ultrasonic probe having one or more piezoelectric ceramic elements, each having a respective bulk acoustic impedance. Each element has a respective front face and a respective piezoelectric ceramic layer integral therewith to provide efficient acoustic coupling between the probe and a medium under examination by the probe. The respective piezoelectric layer of each element includes shallow grooves disposed on the respective front face of each piezoelectric element. A groove volume fraction of the piezoelectric layer is selected to control acoustic impedance of the piezoelectric layer so as to provide a desired acoustic impedance match between the bulk acoustic impedance of the element and an acoustic impedance of a medium under examination by the probe. Electrodes extend into and contact the grooves, imposing electrical boundary requirements that support a desired electrical field distribution within the element.

Abstract: An ultrasonic transducer for controlling an elevation aperture utilizes the electric field-induced polarization properties of relaxor ferroelectric materials. The Curie temperature of the material is typically close to room temperature, so that the application of a bias voltage provides piezoelectric activity. By varying the thickness of a dielectric layer that spaces apart the relaxor ferroelectric material from an electrode or providing the bias voltage, the piezoelectric activity can be tailored. That is, degrees of polarization of the relaxor ferroelectric material are varied spatially in correspondence with changes in thickness of the dielectric layer. The effective elevation aperture of the transducer can be varied by adjusting the bias voltage.

Abstract: An ultrasonic probe including one or more piezoelectric ceramic elements mounted on an acoustically damping support body. Desired acoustic signals are transmitted and received through a front portion of the probe while unwanted acoustic signals are dampened by the support body at the rear portion of the probe. The present invention generates and efficiently focusses a main lobe of a beam of the acoustic signals. Furthermore, the invention provides for apodization of the acoustic beam to reduce extraneous acoustic signals corresponding to side lobes of the acoustic beam. Each element has a respective rear face and a respective first piezoelectric ceramic layer integral therewith to provide efficient acoustic coupling between the element and the acoustically damping support body. The respective first piezoelectric layer of each element includes shallow grooves disposed on the respective rear face of each piezoelectric element.

Abstract: An apparatus for use in flow monitoring and cannulation of blood vessels which includes vascular accessing capabilities. The apparatus includes a flux panel, an audio monitor, and a probe-needle assembly. The flux panel is composed of two or more sections hingedly connected wherein each section includes a transducer having a continuously varying thickness from one end to the other. Successive bands of excitation are progressively created along the length of each transducer as different frequencies are transmitted thereto. The apparatus may be operated in either monitor or access modes with both manual and automatic changes frequencies. The apparatus is capable of transmitting high-powered ultrasonic waves of continuously variable resonant frequencies to be used along with an audio monitor for sensing flow or in conjunction with a probe-needle assembly to locate body vessels.

Abstract: A piezoelectric resonator vibrating in the thickness shear-slide mode comprises an elongated ceramic piezoelectric substrate, first and second terminal electrodes formed on both end portions of a front major surface thereof and first and a second vibrating electrodes connected with the first and the second terminal electrodes through first and second extracting electrodes respectively. A third terminal electrode is formed on a central portion of a rear major surface of the substrate, while a third vibrating electrode is formed at a position opposite to the first and the second vibrating electrodes, so that the third terminal electrode is connected with the third vibrating electrode through a third extracting electrode. An auxiliary electrode extends from the third vibrating electrode toward a position opposed to the first terminal electrode.

Abstract: A composite type piezoelectric component has electrodes formed on both major surfaces of a piezoelectric device. These electrodes are electrically connected and mechanically attached to two terminals having top ends shaped so as to receive and support both ends of the piezoelectric device. A capacitor is constructed with a pair of divided electrodes formed on one major surface of a dielectric substrate and another such pair on the other major surface thereof. The capacitor is attached to the two terminals by joining the divided electrodes on one of the major surfaces of the capacitor to the top ends of the terminals so as to leave a clearance between the capacitor and the piezoelectric device. A third terminal is connected to both of the other pair of divided electrodes. These two pairs of electrodes are substantially equally shaped such that directionality is not critical when the capacitor is attached to the terminals.

Abstract: A method of directly bonding a crystal to a crystal includes the steps of mirror-polishing the surfaces of the crystals and then rinsing them with a cleaning material and then affecting a baking operation and then bonding them together and thereafter annealing them within a temperature range where crystal crystallization is not transited in phase so that a further strong bonding force is obtained. A crystal resonator is obtained where electrodes are oppositely established across a ply crystal blank with at least two sheets of crystal blanks having a desired cut angle and a desired thickness being directly bonded so that the respective crystal axes intersect at the desired angles. The ply crystal blank may have a central portion which is either thicker or thinner than a surrounding portion.

Abstract: A piezoelectric filter in which an earth electrode is provided in the center of a piezoelectric substrate in the direction of thickness; an input electrode is provided on the upper surface of the piezoelectric substrate so as to be opposed to one part of the earth electrode; an output substrate is provided on the lower surface of the piezoelectric substrate so as to be opposed to another part of the earth electrode except the aforementioned one part; a first dummy electrode is formed on the upper surface of the piezoelectric substrate so as to be opposed to the output electrode through the piezoelectric substrate; and a second dummy electrode is formed on the lower surface of the piezoelectric substrate so as to be opposed to the input electrode through the piezoelectric substrate.

Abstract: A plurality of piezoelectric resonators (10,32,37,57,62,66,79,88,93) are utilized to form a bandpass filter (31,56,78). The resonators (10,32,37,57,62,66,79,88,93) are connected in parallel to form a plurality of parallel paths between an input (43,73,81) and an output (47,74,82) of the filter (31,56,78). A predetermined number of the piezoelectric resonators (10,32,37,57,62,66,79,88,93) provide a phase shift of approximately 180 degrees. Each parallel path has a passband and center frequency that is displaced from the passband and center frequency of other paths. Consequently, the passband of each parallel path algebraically sums and creates a filter passband that is wider than the passband of each of the filter's individual parallel paths.

Abstract: A piezoelectric filter of an energy-trapped type utilizing a second harmonic wave of the thickness-extensional vibration mode, characterized in that an earth electrode is formed around the center of a piezoelectric substrate in the direction of thickness, and an input electrode and an output electrode are formed on one or both major surfaces of the piezoelectric substrate so as to be opposed to the earth electrode.

Abstract: The method comprises decomposing an original resonator within a network into a pair of series connected resonators to add an additional connecting electrode to the network. The pair of resonators are series connected by a shared electrode. To preserve the original electrical characteristics of the network, the composite characteristics of the series connected resonators are chosen to match those of the original resonator. With this method, the additional electrode is placed on a surface of the piezoelectric material opposing the surface to which the shared electrode is mounted. The method allows for the addition of an electrode to a piezoelectric resonator-based network so that the electrodes which connect the network to other circuitry may be placed where desired. This may be on the upper surface of the piezoelectric material for connection to discrete components or on the lower, buried surface for connection to buried layers of an adjacent integrated circuit.

Abstract: A driving device includes a driving member which is frictionally engaged with a driven member or a member coupled to the driven member and which is movably supported on a fixed member, a piezoelectric element disposed in contact with the driving member, and a driving circuit for applying a voltage to the piezoelectric element so as to make the speed of expansion of the piezoelectric element different from the speed of contraction thereof.

Abstract: A miniature thin film microwave frequency acoustic filter device comprising acoustic resonators formed on the same dielectric membrane so that their frequency responses are identical. Because the filters are miniature, they can be manifolded without manifolding circuitry that normally causes significant filter losses.

Abstract: A crystal exhibiting a variable index of refraction in response to a voltage applied across it is driven from a lower voltage signal generator through a passive resonant circuit. The resonant frequency of the circuit is tunable by hand in order to maximize the voltage applied to the crystal from a low voltage signal generator. The impedance of the circuit is also hand adjustable in order to match that of the signal generator. The crystal and driving circuit are packaged together in a single enclosure having optically transparent windows allowing a laser beam to pass through the crystal and be modulated by it according to the frequency of the signal generator.

Abstract: A film bulk acoustic resonator (FBAR) configured as a coplanar transmission line structure. A film resonator formed over an opening in a substrate is connected to associated circuitry by one or more transmission lines formed on the substrate. The coplanar ground plane of this structure provides a simple mechanism for providing a true ground connection to the resonator without the need for vias passing through the substrate. The transmission line connection eliminates the need for wirebonds, thus simplifying fabrication, allowing the device to be more easily modified for computer simulation, and facilitating the operation of the device at microwave frequencies. Embodiments for standard, stacked, and 3-port FBAR's as well as a filter bank consisting of a plurality of coplanar 3-port FBAR's, are described.

Abstract: In a method of applying a cavity forming material onto vibrating electrode parts provided on front and back surfaces by supplying the cavity forming material from above an uprightly arranged piezoelectric substrate, a cavity is defined not only around the vibrating electrode parts but also along the upper edge portion of the piezoelectric substrate upon sealing with armoring resin, since the cavity forming material partially remains on the upper edge portion of the piezoelectric substrate. Thus, necessary damping is not performed and spurious vibration is increased. According to the present invention, a solder damping electrode is provided at least on one of front and back surface portions of the piezoelectric substrate close to the upper edge portion supplied with the cavity forming member and solder is provided on this electrode, whereby spurious vibration of the upper edge portion of the piezoelectric substrate is damped by additional mass of the solder.

Abstract: An arrangement is provided for removing foreign substances from a mirror. A vibrator for vibrating the mirror includes a vibration controlling unit for supplying power to the vibrator. As the vibration controlling unit is located close to the vibrator, the length of the conductive wire which transmits the power can be minimized so as to reduce radio noise. The heat generated by the vibration control unit can be radiated sufficiently through a metallic case member and the vibration controlling unit can be disposed in the closed, small space between the mirror and the housing. Therefore, the size of the housing can be reduced so as to minimize the space which surrounds the vibration control unit. Further, the vibration control unit can be protected from contamination due to the closed case member.

Abstract: A radial lead type electronic component includes a couple of plate-type lead terminals projecting from a protective resin member in the same direction. These lead terminals are provided with inclined edges, which make the body portions gradually narrowed toward leg portions, in leg-side edges of body portions. Among inclined edges, inclinations .theta..sub.1 of the outer ones with respect to the leg-projecting direction are greater than inclinations .theta..sub.2 of the inner ones with respect to the same direction. Thus, the electronic component is relieved from stresses which are applied thereto upon insertion in a printed circuit board or a cut-and-clinch operation.

Abstract: A piezoelectric device operable in the thickness shear vibratory mode, and a method for manufacturing the piezoelectric device. In the piezoelectric device, a rectangular piezoelectric plate is polarized to have its polarization axis inclined to both the long and short sides thereof. This is accomplished by applying a predetermined electric field to the piezoelectric plate in the direction of the long side thereof, after applying a predetermined electirc field to it in the direction of the short side thereof. A pair of electrodes are formed on the piezoelectric plate so that the piezoelectric device is operable in the thickness shear vibration mode.

Abstract: A piezoelectric vibration component of an energy trapped type operable in a thickness slip vibration mode includes a piezoelectric substrate having front and back faces and rectangular configuration with long and short sides. The piezoelectric substrate is polarized in a direction approximately parallel to the short side of the piezoelectric substrate. Vibrating electrode members are deposited on the front and back faces of the piezoelectric substrate.

Abstract: A piezoelectric vibrating device utilizing a thickness shear vibration mode, in which at least one pair of vibrating electrodes is formed on both major surfaces of a piezoelectric substrate so as to have regions opposed to each other through the piezoelectric substrate and an edge of the vibrating electrode on one of the major surfaces which exists in the region opposed to the vibrating electrode on the other major surface is provided with irregularities.

Abstract: A piezoelectric oscillator containing load capacitances utilizing the thickness shear vibration mode of a piezoelectric plate. In this piezoelectric oscillator, a pair of divided electrodes are formed on one major surface of a piezoelectric plate and are divided by a gap provided in a direction extending from one end surface to the other end surface of the piezoelectric plate, and the pair of divided electrodes are formed so as to be opposed to a common electrode formed on the other major surface of the piezoelectric plate through the piezoelectric plate.

Abstract: A piezoelectric filter of an energy-trapped type utilizing a second harmonic wave of the thickness-extensional vibration mode, characterized in that an earth electrode is formed around the center of a piezoelectric substrate in the direction of thickness, and an input electrode and an output electrode are formed on one or both major surfaces of the piezoelectric substrate so as to be opposed to the earth electrode.

Abstract: A piezoelectric resonator of an energy-trapped type utilizing a second harmonic wave of the thickness-extensional vibration mode, in which an inner electrode is formed in a position at a height around the center of a piezoelectric substrate in the direction of thickness, outer electrodes are formed on both major surfaces of the piezoelectric substrate so as to be opposed to the inner electrode through a piezoelectric substrate portion, and the dimension of at least one of the outer electrodes in the direction of the length of the inner electrode is made smaller than the dimension of the outer electrode in the direction of the width of the inner electrode.

Abstract: A piezoelectric filter device of an energy-trapped type utilizing a higher harmonic in the thickness-extensional vibration mode, having a plate-shaped body made of a piezoelectric material. At least three electrodes are arranged so as to overlap each other while being separated by layers of the piezoelectric material in the direction of thickness of the plate-shaped body. At least one of the electrodes comprises a plurality of divided electrodes which are substantially coplanar. At least one of the divided edlectrodes constitutes an input terminal and at least one of the remaining divided electrodes constitutes an output terminal. A region of the body, around the vibrating region, where the electrodes are overlapped with each other, is uniformly subjected to polarization processing in the direction of thickness.

Abstract: Disclosed is an energy-trapping-by-frequency-lowering-type piezoelectric-resonance device utilizing a higher harmonic in the mode of thickness-extensional vibration, in which at least three electrodes for energy trapping are arranged so as to be overlapped with each other in the direction of thickness of layers of piezoelectric material forming a plate-shaped body. The three electrodes comprise a pair of outermost electrodes and at least one inner electrode. The diameter of one polygonal side of at least one outermost electrode is made larger than the diameter of one polygonal side of an inner electrode.

Abstract: A crystal resonator device having a plurality of coupled resonators in which the relative phase and magnitude of the resonator excitation currents is controlled by electrical circuit means such as reactance components connected in series with one or more of the resonators to thereby minimize or otherwise control the acceleration sensitivity of the device.

Abstract: An energy trapping type piezoelectric resonance device utilizing higher-order harmonics of the thickness extensional vibration mode comprising a body formed of a piezoelectric material and three or more electrodes arranged overlapping with each other and separated by the piezoelectric material layers in the direction of thickness of the body, wherein respective portions of the piezoelectric material layers interposed between the electrodes are polarized and at least respective portions of the piezoelectric material layers which are not interposed between the electrodes is polarized.

Abstract: An electronic component comprises a plate-shaped element, electrodes being formed on both main surfaces of this plate-shaped element. A metal plate having nearly the same shape and nearly the same size as the element is provided for supporting one main surface of the element. The electrode on this surface of the element is connected to the metal plate, to which one lead terminal is connected. Further lead terminals are provided beside the element, having tips which are bent inside so as to face each other, and are connected to corresponding electrodes formed on the other main surface of the element. The metal plate reinforces and shields the plate-shaped element.

Abstract: A piezoelectric resonance device of the energy-trapped type utilizing a harmonic wave of the thickness extensional vibration mode, wherein three or more electrodes are so disposed that they are overlapped with each other through the piezoelectric layer in the direction of the thickness and each of the electrodes is comprised of a vibrating electrode portion for energy-trapping and a conducting portion for connecting the vibrating electrode to the side edge of the piezoelectric layer.

Abstract: A large number of piezoelectric elements are arranged in a mosaic pattern on a spherical surface so that ultrasonic waves generated by the elements converge on a single point. The arrangement of the elements constitutes a transducer. With the transducer applied to a subject through a liquid bag filled with water, ultrasonic shock waves from each piezoelectric element are concentrated on a lithotresis object, or a calculus so as to break it. The ultrasonic shock waves are generated by applying driving impulses (voltage) to each piezoelectric element. In order to locate the calculus, the transducer is coupled to an ultrasonic diagnosis apparatus having a mechanical scanning type ultrasonic probe. The piezoelectric elements have resonance frequencies set such that the piezoelectric element positioned at the center of the transducer has the lowest resonance frequency and the resonance frequency of each piezoelectric element is increased in accordance with its distance from the center.

Abstract: An energy trapping type piezoelectric resonance device utilizing the mode of thickness extensional vibration comprises a plate-shaped body of a piezoelectric material and three or more electrodes provided to be opposed to each other through peizoelectric material layers in the direction of thickness of the body. At least one of the electrodes is provided to be smaller in area than the major surfaces of the body, to be capable of energy trapping.

Abstract: At least one pair of exciting electrodes are formed opposite to each other on two major surfaces of a piezoelectric plate. Electrodes and that portion of the piezoelectric plate which is held between at least the exciting electrodes, form a resonance region where thickness-shear vibrations of plural modes are excited. A waveguide path having a cut-off frequency higher than the frequency of at least one desired vibration excited in the resonance region, but lower than the frequencies of the thickness-shear vibrations, whose damping is desired, and excited in the resonance region, is formed and extends in a direction substantially the same as the propagating direction of the thickness-shear vibration whose damping is desired, and has a width 0.5 times or more the width of the resonance region. A vibration absorbent is arranged in the waveguide path.

Abstract: A chip-type resonator comprises a piezoelectric member, a plurality of inner electrodes embedded in the piezoelectric member parallel to one another and spaced apart at intervals along the direction of thickness, and a pair of outer electrodes provided on side surfaces of the piezoelectric member and connected with the inner electrodes. The inner electrodes are provided in an odd number of at least three. The piezoelectric member is so polarized that one of its portions located between one pair of the inner electrodes expands and another portion between an adjacent pair contracts upon application of voltage between the outer electrodes.This chip-type resonator is manufactured by preparing a plurality of sheets for providing a piezoelectric member, forming electrodes on the same, stacking and firing the same and performing the prescribed polarization.

Abstract: A manufacturing method for an integrated resonator is disclosed wherein a mass of O.sup.+ ions are implanted into a silicon monocrystal substrate from one side thereof, a buried SiO.sub.2 layer is formed by annealing the ion implanted substrate, an SiO.sub.2 layer is formed on the surface of the substrate by oxidizing it, at least one slit is formed on the SiO.sub.2 layer for etching a predetermined area of the silicon monocrystal layer sandwich between two SiO.sub.2 layers to form a cavity and, a piezo-electric resonator is formed on an area of the surfacial SiO.sub.2 layer corresponding to the cavity in the substrate.