Abstract: A piezoelectric device includes a piezoelectric substrate having a piezoelectric driving unit and provided with outer coating substrates laminated on major surfaces thereof via adhesive layers, and external electrodes provided on the outer surfaces of a layered body included in the piezoelectric device. In the piezoelectric device, each of the adhesive layers includes a first layer of an adhesive having a Shore D hardness after curing of not more than approximately 60, and disposed so as not to be exposed in a region of lateral side surfaces of the layered body provided with the external electrodes, a second layer of an adhesive having a Shore D hardness of at least approximately 60, and a third layer of an adhesive having a Shore D hardness of at least approximately 60 and having a viscosity before curing of at least approximately 3.0×105 mPas at a temperature of 25° C.

Abstract: A piezoelectric component includes leads and being arranged to suppress the adhesion of solder or a conductive adhesive agent to lead-out electrodes or vibration electrodes thereof, which is therefore resistant to the deterioration of electrical characteristics such as resonance characteristics, and which minimizes fluctuation of the electrical characteristics. In this piezoelectric component having the leads, the vibration electrodes are provided on each of the first and second main surfaces of a piezoelectric plate, and each of the vibrating electrodes is connected to a terminal electrode via a lead-out electrode. Each of the holding portions of a lead terminal is bonded to the terminal electrode, and is arranged so as not to extend onto the lead-out electrode.

Abstract: A quartz crystal unit with favorable frequency variation characteristics in response to changes in temperature and changes over time. A pair of lead wires provided perpendicularly to a base and a pair of supporters supported on the pair of lead wires are used for holding and electrically connecting a quartz blank at opposite points on the periphery thereof to which leading electrodes extend. The orientation of a line connecting holding points matches an axis on which stress sensitivity of the quarts blank exhibits the least value. A line connecting both supporting points for the supporters by the lead wires is disposed in a skew position with respect to another line connecting both holding points for the quartz blank. When the quartz blank is AT cut, an angle formed between these lines in the skew relationship is preferably set to approximately 30 degrees.

Abstract: A piezoelectric resonator vibrates in a square vibration mode and includes a piezoelectric substrate having a first major surface and a second major surface, electrodes provided on the first major surface and the second major surface of the piezoelectric substrate and a groove provided in at least one of the first major surface and the second major surface of the piezoelectric substrate. The groove divides at least one of the electrodes into a plurality of areas such that the electrostatic capacitance of the resonator is changed by varying the position, the width and the depth of the groove provided on the piezoelectric substrate.

Abstract: A piezoelectrically active conformal filler material is incorporated in a 1-3, 3-3 or 2-2 piezocomposite structure. The piezoelectrically active conformal filler material has a 0-3 structure and is made of fine piezoelectric ceramic particles surrounded by a conformal polymer matrix. Using such piezocomposite material, the reception and transmission sensitivity (efficiency) of a piezoelectric layer can be improved without any increase in the acoustic impedance of the final piezoelectric layer. The resulting piezocomposite material can be used to fabricate ultrasonic transducer arrays.

Abstract: A piezoelectric ceramic comprising lead titanate as a primary component, wherein the primary component contains a titanium oxide crystalline phase. Methods for producing the ceramic, and piezoelectric oscillators making use of the ceramic are also disclosed.

Abstract: An energy-trap type piezoelectric resonator utilizes a fundamental wave of a thickness shear vibration mode and includes resonance electrodes provided on both main surfaces of a substantially rectangular piezoelectric plate so as to face each other with the piezoelectric plate disposed therebetween. An energy trap vibration portion including a portion of the piezoelectric plate where the resonance electrodes overlap each other is asymmetrical with respect to the center in the longitudinal direction of the piezoelectric plate.

Abstract: An object of the invention is to provide a piezoelectric bulk acoustic wave device having a high effective electromechanical coupling constant and allowing a fractional bandwidth to be broadened when applied to a filter and a normalized frequency variable width to be broadened when applied to an oscillator. Another object of the invention is to provide a miniature piezoelectric bulk acoustic wave device capable of operating at a high frequency of several hundreds of megahertz while maintaining a high electromechanical coupling constant. The piezoelectric bulk acoustic wave device includes a piezoelectric substrate constructed of a single crystal or oriented crystal body of potassium niobate and having a pair of major surfaces, and at least one pair of opposed electrodes formed on the major surfaces of the piezoelectric substrate, respectively, wherein the device utilizes thickness vibration propagating along the major surfaces.

Abstract: A wafer with a reversed domain is prepared for two piezoelectric single crystal plates and of about the same thickness by using direct bonding without any adhesive. Driving electrodes are formed on two principal planes of the wafer with a reversed domain to provide a piezoelectric resonator. A piezoelectric resonator having the structure with a reversed polarization and using odd-order vibration modes vibrating with a fundamental wave has a wavelength of a thickness thereof and suppresses scattering of the thickness of the domains with a reversed polarization. In the direct bonding, the axes of the spontaneous polarization of the two piezoelectric single crystal plates are reverse to each other and crystalline axes other than the axes of polarization are shifted intentionally by an angle other than zero. Thus, spurious modes are suppressed in a simple way.

Abstract: A piezoelectric vibration device utilizes a thickness-shear vibration available for communication devices or the like. The piezoelectric vibration device has a structure wherein at least one of each peripheral zone of an input electrode (21) and an output electrode (22), or a common electrode (23), where the non-harmonic overtone mode is relatively strongly excited, is partially provided with either a weight reducing portion (231, 232) or a weight adding portion. Moreover, an area of the common electrode (23) is larger than a total area of the input electrode (21) and the output electrode (22), and either the weight reducing portion (231, 232) or the weight adding portion reaches the common electrode (23) opposed to the input electrode (21) and the output electrode (22). Preferably, the common electrode formed on one principal plane of a quartz plate (1) is twice to 10 times as thick as the input electrode (21) and the output electrode (22) formed on the other principal plane.

Abstract: An energy-trap thickness extensional vibration mode piezoelectric resonator uses a harmonic of a thickness extensional vibration mode and effectively suppresses generation of unwanted spurious vibrations. The energy-trap thickness extensional vibration mode piezoelectric resonator includes a piezoelectric strip, first and second excitation electrodes located on opposite surfaces of the piezoelectric strip, and an internal electrode disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite ends of the piezoelectric strip in an overlapping arrangement. The internal electrode is located opposite to the first and second excitation electrodes. The first and second excitation electrodes overlap each other over a length of l such that l/d is not greater than about 6, where d=t/n.

Abstract: An energy-trap piezoelectric resonator utilizing thickness extensional vibration includes a piezoelectric substrate and first and second resonance electrodes. The piezoelectric substrate is polarized in the thickness direction thereof and has first and second main surfaces. The first resonance electrode is partially disposed on the first main surface of the piezoelectric substrate, and the second resonance electrode is partially disposed on the second main surface of the piezoelectric substrate. The second resonance electrode is arranged to oppose the first resonance electrode with the piezoelectric substrate disposed therebetween and has an external dimension that is different from that of the first resonance electrode.

Abstract: A thickness-extensional piezoelectric resonator using a harmonic of a thickness-extensional vibration mode has a compact size, large electric capacity, and small variations in resonance characteristics, and is not affected by the stray capacitance of a circuit board. The thickness-extensional piezoelectric resonator includes a substantially rectangular-plate piezoelectric body, a first excitation electrode and a second excitation electrode disposed on individual surfaces of the piezoelectric body, and an internal electrode inside of the piezoelectric body. Portions where the first excitation electrode, the second excitation electrode and the internal electrode overlap define a resonating portion. In the length direction of the piezoelectric body, a vibration-attenuating portion is defined at each side of the resonating portion, whereas in the width direction, the vibration-attenuating portion is not provided at each side thereof.

Abstract: A capacitor-included, chip-type piezoelectric resonator allows minute and highly precise adjustment of electrostatic capacitance and the resonance frequency after production of the piezoelectric resonator by laminating a piezoelectric element and dielectric substrates. The resonator includes a piezoelectric substrate laminated with dielectric substrates and external electrodes disposed on the laminate body. A plurality of external electrodes are arranged to extend from the outer major surface of the first dielectric substrate to the outer major surface of the second dielectric substrate along first and second side surfaces disposed opposite to each other. On the outer major surface of the second dielectric substrate, at least one external electrode is divided into first and second electrode portions.

Abstract: An instrumented sports apparatus includes a closely spaced array of discrete sensor elements coupled to a contact surface thereof for converting a contact force between the contact surface and an object into a plurality of discrete output signals. The signals are processed and information based thereon generated, which is representative of one or more parameters of interest. In an exemplary embodiment, as instrumented golf club displays information such as club head speed, club head angle, and club head elevation upon impact with a golf ball, permitting the golfer to adjust his swing on the next stroke. Since the instrumentation and display are entirely self-contained in the club, a golfer is not constrained in the use of the club and may enjoy the benefits thereof during play on a golf course.

Abstract: A thickness extensional vibration piezoelectric resonator includes a strip-type, substantially rectangular plate-shaped piezoelectric body, first and second excitation electrodes disposed on both sides of the piezoelectric body, the back side and the front sides thereof being opposed to each other with the piezoelectric body disposed therebetween, and an internal electrode disposed in the piezoelectric body. The resonator portion where the first and second excitation electrodes and the internal electrode are opposed to each other define a resonance portion. In the longitudinal direction (a first direction) of the piezoelectric body, vibration-attenuating portions are provided on both sides of the resonance portion. The ratio L/D is within the range of about 9.0 to about 14.0, in which L is the length in the longitudinal direction of the piezoelectric body, T is the thickness, and wherein D=T/N.

Abstract: An ultrasonic wave applying apparatus which is safe and convenient for use. The apparatus includes an hand-held applicator having a vibration element which is, in use, contact with a skin of a user to apply ultrasonic waves to the skin, a power source providing a DC voltage, an oscillator circuit which is energized by the DC voltage from the power source to generate an oscillating output for driving the vibration element, and a load detecting circuit which monitors whether the vibration element is loaded such as by contact with the skin and provides a load detection signal when the vibration element is so loaded. In addition, a motion detecting circuit is provided to monitor whether the vibration element is moving and give a motion detection signal when the vibration element is so moving.

Abstract: A piezoelectric resonator includes two sealing substrates, a seal portion, and an energy-trap type piezoelectric resonance element which is adapted to vibrate in a third harmonic of thickness extensional vibration. The piezoelectric resonance element includes a piezoelectric substrate and a pair of excitation electrodes, which are disposed on opposite major surfaces of the piezoelectric substrate. A portion of the piezoelectric substrate sandwiched by the excitation electrodes defines a vibrating portion. The sealing substrates each have a cavity formed therein and are attached onto the corresponding major surfaces of the piezoelectric substrate such that the cavities define a space for vibration. The seal portion is formed around the vibration space so as to damp leaking vibration. The vibrating portion is arranged such that the approximate center thereof is spaced from the approximate center of the vibration space as viewed along the major surfaces of the piezoelectric resonance element.

Abstract: A piezoelectric vibratory gyroscope utilizing an energy-trapping vibration mode comprises a piezo-electric plate having a principal surface and polarized in a thickness direction, and first through n-th electrodes (n being an integer not smaller than three) formed in a generally central area of the principal surface at positions corresponding to first through n-th vertexes of a polygon having n angles. When the piezoelectric plate is excited in the energy-trapping vibration mode of a primary vibration, rotation of the piezoelectric plate around an axis perpendicular to the principal surface of said piezoelectric plate produces the Coriolis force to excite a secondary vibration which induces electric voltages at the first through the n-th electrodes. A voltage difference is detected for at least two of the first through the n-th electrodes.

Abstract: A piezoelectric resonant part includes a piezoelectric substrate having first and second opposed main surfaces, electrode patterns formed on the main surfaces; and protective substrates bonded to respective ones of the main surfaces of the piezoelectric substrate via adhesive layers to form a laminate. Each of the adhesive layers comprising a first layer made of a soft adhesive whose Shore hardness is less than D60 and a second layer made of a hard adhesive whose Shore hardness is more than D60. External electrodes are formed on exposed surfaces of the piezoelectric resonant part. Only the second adhesive layers are exposed in the areas where the external electrodes are located such that the external electrodes do not contact the relatively soft first adhesive layers. The piezoelectric resonant part is made by forming a respective first adhesive layer on a main surface of each of the protective substrates and then forming a respective second adhesive layer on each of the first layers.

Abstract: An energy trap type piezoelectric resonator includes a plate-like piezoelectric resonator element constructed to vibrate in a third harmonic of a longitudinal vibration mode in a thickness direction thereof and such that both main surfaces of the resonator element are laminated with sealing substrates. Sealed spaces are provided so as to allow a vibrating portion of oppositely disposed vibrating electrodes to vibrate. Sealing portions, in which the piezoelectric resonator element and the sealing substrates are joined and connected around the sealed spaces, are constructed so that when the thickness of a piezoelectric substrate is represented by t and the shortest distance to the sealing portion from the vibrating electrodes is d, the sealed spaces satisfy the relationship 0<d/t<5.

Abstract: In a piezoelectric vibrator which has excitation electrodes respectively disposed on the top surface and undersurface of a piezoelectric substrate, at least one of the excitation electrodes being an inverted-mesa electrode that has a recess formed in the opposite side of the electrode from the side which contacts the piezoelectric substrate. Thus, an AT-cut quartz resonator in which the capacitance ratio .gamma. is reduced to a value below the limit value can be provided as a result of use of the inverted-mesa electrodes as excitation electrodes.

Abstract: A thickness extensional piezoelectric resonator includes a substantially rectangular piezoelectric strip, first and second excitation electrodes disposed on both surfaces of the piezoelectric strip, and an internal electrode disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite sides of the piezoelectric strip. The internal electrode is located opposite to the first and second excitation electrodes. Assuming that the piezoelectric plate has a width W and a thickness t, the piezoelectric plate is constructed such that W/d is less than about 6.1 if d=t/n.

Abstract: A piezoelectric vibration device is constructed to suppress interference between resonance sections and achieve a satisfactory resonance characteristic and sufficient mechanical strength. In the piezoelectric vibration device, a plurality of resonance sections are provided on a piezoelectric substrate and a slit is provided so as to extend from one side of the piezoelectric substrate toward a center thereof in order to suppress interference between the resonance sections. If the length of the slit is denoted as a, the gap width along the opposing direction of the first and second resonance electrodes in the resonance section as g, the distance from the center of the gap to the nearest side of the piezoelectric substrate and the sides of the slit as L.sub.1, and the external dimension of the piezoelectric substrate along one direction as L, then the expression L.sub.1 -g/2=b, b<a.ltoreq.(3/4)L is satisfied.

Abstract: A unit for suppressing harmonic vibration of a lower order which does not have desired frequency in an overtone resonator consisting main electrodes and sub electrodes. Harmonic vibration of a lower order suppressing piezoelectric vibrator comprises main electrodes arranged on a piezoelectric substrate and sub electrodes arranged in the vicinity of the main electrodes with gaps provided therebetween. If the electric equivalent circuit of the resonator is expressed by a coupling circuit which connects in series a circuit, which connects in parallel a series resonance circuit by the sub electrodes and coupling capacity indicating that the main electrodes are coupled with the sub electrodes, to a series resonance circuit by the main electrodes, then their loop frequencies substantially coincide with each other.

Abstract: An energy-trapping piezoelectric resonator vibrates in a third-order wave of a thickness-extension vibration mode. The piezoelectric resonator includes a piezoelectric substrate polarized along its thickness. A ratio of the width W to the thickness T of the substrate is determined to be about 0.88.+-.5%, 1.06.+-.4%, 1.32.+-.5%, 1.80.+-.3%, 2.30.+-.3%, 2.69.+-.3%, 3.16.+-.2%, or 3.64.+-.2%. First and second electrodes are respectively disposed on the obverse and reverse surfaces of the substrate to cover the entire width and opposedly face each other at the central portion of the substrate in the longitudinal direction so as to form a resonance portion between the first and second electrodes.

Abstract: A thickness extensional piezoelectric resonator utilizes harmonics of a thickness extensional vibration mode and has a significantly reduced size and significantly increased capacitance while not being susceptible to the effects of the stray capacitance of a circuit board upon which the resonator is mounted. The resonator includes a piezoelectric strip, first and second excitation electrodes located on one of two respective major surfaces of the piezoelectric strip, and internal electrodes disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite sides of the piezoelectric strip. The internal electrodes are located opposite to the first and second excitation electrodes to thereby define a vibrating portion. Vibration-attenuating portions are located on opposite sides of the vibrating portion only along the longitudinal direction of the piezoelectric strip. No vibration-attenuating portions are located in the lateral direction of the piezoelectric strip.

Abstract: An energy-trap thickness extensional vibration mode piezoelectric resonator utilizes a harmonic of a thickness extensional vibration mode achieves excellent resonant characteristics that are hardly affected by portions of the resonator which are physically supported. The energy-trap thickness extensional vibration mode piezoelectric resonator includes a piezoelectric strip, first and second excitation electrodes located on opposite surfaces of the piezoelectric strip, and an internal electrode disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite ends of the piezoelectric strip in an overlapping arrangement. The internal electrode is located opposite to the first and second excitation electrodes. The resonator is designed so that a ratio L/d is not less than about 14, where L is the dimension of the piezoelectric strip 2 in the longitudinal direction, t is the thickness, and d=t/n.

Abstract: A piezoelectric resonator adapted to generate a harmonic wave in a thickness extensional vibration mode includes a piezoelectric member, a plurality of excitation electrodes disposed on or within the piezoelectric member and superposed on one another in the thickness direction of the piezoelectric member with piezoelectric layers of the piezoelectric member interposed therebetween, lead-out electrodes respectively connected to the excitation electrodes and extending to side surfaces of the piezoelectric member at the same vertical positions as the excitation electrodes, and a dummy electrode disposed at least one of the vertical positions at which the excitation electrodes are disposed and at such a position so as to have a symmetrical relationship relative to the corresponding excitation electrode with the lead-out electrode connected to the excitation electrode.

Abstract: An acoustic transducer has two separate elements which are driven by separate signal generators to produce two acoustic beams that focus at the same target location. The two acoustic beams interact at the target location to produce a beat force. The target location is moved to scan a subject by mechanically moving the acoustic transducer, or the two intersecting acoustic beams can be steered electronically to move the target location.

Abstract: An energy trapping piezoelectric device trapping a thickness vibration into projections which suppress a reflection of a vibration from end portions of electrodes provided substantially on a piezoelectric plate, and which suppress unnecessary spurious vibrations, low impedance and higher frequency, and a method of easily producing such a piezoelectric device are provided. The piezoelectric device has an energy trapping projection provided over a piezoelectric plate, and a top electrode is divided into a exciting electrode and dummy electrode. A small gap is provided between the divided electrodes, and the electrodes are electrically insulated from each other. The thickness vibration is not generally reflected, and vibrating energies due to the thickness vibrations are substantially trapped into the projections provided on the piezoelectric plate.

Abstract: An energy-trapping thickness-shear resonator includes a piezoelectric substrate, a first electrode extending from a first end to a central portion of a first surface of the piezoelectric substrate and a second electrode extending from a second end to the central portion of a second surface of the substrate. Thus, the resonator utilizes thickness shear vibrations generated in a portion of the piezoelectric substrate located between the first and second electrodes at the central portion of the substrate. The width W of the la substrate is set to be equal to or less than about 0.7 mm and also to satisfy both of the following expressions (1) and (3) or to satisfy both of the expressions (2) and (3):(1) 0<W<k T/(1-a)(2) k(2n-1)T/(1-a)<W<k(2n+1)T/(1-a)(3) 0 21 .alpha.<(fa-fr)/fawhere T indicates the thickness of the piezoelectric substrate; k is 1/2; f.sub.OSC equals fa (1-.alpha.); f.sub.

Abstract: A microwave filter made of piezoelectric resonators fabricated in a monolithic device. Combinations of resonators connected in series and and parallel to each other are laid out in a symmetrical compact arrangement providing symmetrical and similar paths connecting the resonators together and to the ground. The symmetrical layout thus avoids differences in the connector inductances that otherwise would degrade filter performance.

Abstract: A wafer with a reversed domain is prepared for two piezoelectric single crystal plates 11 and 12 having about the same thickness as each other by using direct bonding without any adhesive. Then, driving electrodes 13 are formed on two principal planes of the wafer with a reversed domain to provide a piezoelectric resonator. A piezoelectric resonator having the structure with a reverses polarization and using odd-order vibration modes vibrating with a fundamental wave has a wavelength of a thickness thereof suppresses scattering of the thickness of the domains with a reversed polarization. In the direct bonding, the axes of the spontaneous polarization of the two piezoelectric single crystal plates are reverse to each other and crystalline axes other than the axes of polarization are shifted intentionally by an angle other than zero. Thus, spurious modes are suppressed in a simple way.

Abstract: A piezoelectric vibrator includes a piezoelectric element having an electromechanical coupling coefficient of a thickness-extensional vibration mode greater than that of a thickness-share vibration mode, and a pair of electrodes arranged on surfaces of the piezoelectric element so that harmonic energy of the thickness-extensional vibration of the piezoelectric element is trapped.

Abstract: A method of manufacturing a composite substrate and the composite substrate manufactured thereby wherein surfaces of first and second substrates having different thermal expansion coefficients are mirror finished and layered on each other. A first heat treatment is applied after which a part of the second substrate is removed to a depth sufficient to expose the first substrate. A final second heat treatment directly bonds the substrates.

Abstract: In an ultrasonic inspection apparatus, a piezoelectric element having a first resonant frequency is stuck to a complex resonance member having a second resonant frequency. The second resonant frequency is determined with a conversion in terms of half wavelength. A resultant ultrasonic probe transmits/receives ultrasonic waves of the first resonant frequency and a plurality of other frequencies. In constructing an ultrasonic tomographic image of the object to be inspected from a received signal obtained by using the ultrasonic probe, the imaging frequency is changed according to the depth in the object to be inspected.

Abstract: A piezoelectric vibratory gyroscope utilizing an energy-trapping vibration mode comprises a piezo-electric plate having a principal surface and polarized in a thickness direction, and first through n-th electrodes (n being an integer not smaller than three) formed in a generally central area of the principal surface at positions corresponding to first through n-th vertexes of a polygon having n angles. When the piezoelectric plate is excited in the energy-trapping vibration mode of a primary vibration, rotation of the piezoelectric plate around an axis perpendicular to the principal surface of said piezoelectric plate produces the Coriolis force to excite a secondary vibration which induces electric voltages at the first through the n-th electrodes. A voltage difference is detected for at least two of the first through the n-th electrodes.

Abstract: A granular detergent composition having a density from 550 to 950 g/liter, said detergent composition comprisingi) a polymeric dye transfer inhibiting agentii) a protease having an isoelectric point below 10iii) a surfactant system which is free of alkylbenzene sulfonate surfactant.

Abstract: Multiple piezoelectric ceramic filter elements have different center frequencies from each other and are cascade connected together. The piezoelectric ceramic filter elements satisfy the condition 0<.vertline.dF.sub.0 .vertline./BW.sub.3 <0.8; where .vertline.dF.sub.0 .vertline. is the absolute value of the frequency difference dF.sub.0 between the center frequencies, and BW.sub.3 is the band width of each piezoelectric ceramic filter element in which the amplitude loss is 3 dB or less. A low insertion loss and an improvement in the group delay characteristics are compatible at the same time.

Abstract: A piezoelectric device includes a stacked crystal filter, a supporting substrate and an acoustic reflector between the filter and substrate for suppressing undesired resonant frequencies. The acoustic reflector includes a set of quarter wavelength layers of alternating higher and lower impedances. The reflector provides a large reflection coefficient for a bandwidth that encompasses only desired frequencies generated by the stacked crystal filter. By changing the nature of the material and the number of layers, the bandwidth and center frequency of the acoustic reflector may be varied to encompass a desired range of frequencies. To reduce the magnitude of side lobes at undesired frequencies, the impedance differences between layers of the reflector are reduced with depth into the reflector. The side lobes may also be reduced by serially connecting two stacked crystal filters having acoustic reflectors of the same material but with a different number of quarter wavelength layers.

Abstract: A high frequency acoustic wave piezoelectric device (10) having parallel etched channels cut into a surface of a piezoelectric substrate so as to form micromachined ridges (20). Top electrodes (30) are located on tops (26) of the ridges (20) and bottom electrodes (32) are located on bottoms of the channels in spacings (22) between ridges (20). The top and bottom electrodes (30, 32) are offset from each other and substantially non-opposing. The electrodes (30, 32) generate a sufficient vertical electrical field (38) when driven to cause the ridges (20) to resonate. A height (28) of the ridges (20) define the operating frequency. The ridges (20) can be made small enough to produce frequencies well over 100 MHz in a fundamental bulk acoustic wave mode.

Abstract: Aluminum is used for the interdigital transducer mounted on a piezoelectric substrate to realize a surface acoustic wave transducer having a small capacity ratio, no spurious resonance, and a low loss. A .theta. rotated Y cut lithium niobate single crystal piezoelectric substrate is used for the piezoelectric material, a metal film of which principal ingredient is aluminum is used for the interdigital transducer, the direction of the interdigital transducer is made parallel to the X-axis of the lithium niobate single crystal, and thick h and electrode pitch P of the interdigital transducer have the following relationship:(.theta.+5).sup.2 /300+11/12.ltoreq.h/P.times.100-8.ltoreq.-0.0001.times.(.theta.+5).sup.3 +0.1625.times.(.theta.+5)+5.5and-30.ltoreq..theta..ltoreq.20.

Abstract: A piezoelectric resonance device wherein both ends of a piezo-resonator which has oscillation electrodes on both sides of a piezoelectric substrate are soldered to the inside of cup portions of input and output terminals respectively, and a pair of opposed capacity electrodes of a capacitor is soldered to the outside of the cup portions. The capacitor has a width larger than that of the cup portions.

Abstract: The invention is directed to resonators and more particularly to an MMIC-compatible resonator which can be fabricated on an MMIC chip using MMIC processing techniques. The MMIC-compatible resonator has a substrate approximately 100 microns thick made of semi-insulating GaAs and/or AlGaAs. The substrate flanks an air via on which is fabricated a thin film piezoelectric semi-insulating GaAs film, comprising the piezoelectrically active element. The piezoelectrically active element is flanked either laterally or from the top to bottom thereof by a pair of electrodes which serve to excite the thickness shear or thickness extensional mode of the thin film piezoelectrically active element. There are a number of III-V and II-VI binary compounds and ternary, and other piezoelectric semiconductor alloys, which can be used for the purposes of the invention. The thin film measures approximately 5 microns or less in thickness and is fabricated on the semi-insulating GaAs, on the ?110!, ?111! or ?100! axis thereof.

Abstract: An end face reflection type surface wave resonator utilizing SH type surface waves capable of providing a plurality of resonance characteristics is formed as a single element. In the surface wave resonator, surface waves are reflected between two opposite end faces of a piezoelectric substrate. The surface wave resonator has IDTs that form first and second resonant units. The distance L between the two end faces is selected to be within a range expressed by (.lambda..sub.1 /2).times.N.sub.1 .+-.(.lambda..sub.1 /20) (N.sub.1 is an integral number) where .lambda.1 represents the wavelength of a surface wave excited by the first resonant unit. The distance L is chosen to be out of a range expressed by (.lambda..sub.2 /2).times.N.sub.2 .+-.(.lambda..sub.1 /20) (N.sub.2 is an integral number) where .lambda..sub.2 represents the wavelength of a surface wave excited by the second resonant unit.

Abstract: Integrated circuits utilizing piezoelectric elements can be advantageously constructed by bonding elements together via direct bonds. Such integrated circuits include an electro-acoustic hybrid integrated circuit such as a voltage controlled oscillator wherein a semiconductor substrate having an active element is bonded through direct bonding to a surface acoustic wave resonator or a quartz oscillator as an electro-acoustic element. A quartz device can also be provided which includes a quartz plate, excitation electrodes on opposite surfaces, and a holding member made of a material having a thermal expansion coefficient substantially equal to that of the quartz plate. The holding member is connected to the quartz plate by direct bonding without using any adhesives. Because the thermal expansion coefficients of the quartz plate and the holding member are equal, no thermal stress occurs in the bonding area.

Abstract: A preliminary ejection sensor of an ink jet recording apparatus includes a vibration plate adapted to vibrate on receipt of an ink droplet ejected from an ejection port on a recording head in order to detect the vibration of the vibration plate depending on variation of a gap between a core and the vibration plate, whereby it can be checked whether ink is ejected from the recording head or not. In addition, the preliminary ejection sensor can check the present ink ejecting state of the recording head. Thus, in contrast with a conventional sensing system wherein ink ejection is sensed by an optical sensor on one side surface of the recording head, the structure of the ink jet recording apparatus can be simplified.

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 two plate-type resonators are laterally coupled with each other with respect to a mounting surface. 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: A piezoelectric transformer (10) operating in a thickness-shear vibration mode (26). The piezoelectric transformer (10) comprises a lithium niobate substrate (12) having first and second acoustically coupled portions (16,22), and a plurality of substantially opposing pairs of primary and secondary electrodes (14,20) disposed thereon. An input AC voltage applied to the primary electrode pairs (14) exciting a thickness-shear vibration (26) which couples to the secondary electrode pairs (20) producing an output AC voltage therebetween. The primary and secondary electrodes (14,20) being electrically connected in various combinations of parallel and series connections to provide a desired step-up or step-down voltage transfer ratio.