Abstract: The acceleration sensitivity of an AT-cut quartz crystal plate resonator is educed by replacing the quartz crystal plate of the resonator with a quartz crystal plate having a flatter plate contour.

Abstract: A ZT-cut quartz crystal resonator comprises two thin rectangular plates connected together by at least one resonant arm which itself is connected to a support zone by a linking bar. A pair of electrodes is provided on the quartz resonator for receiving alternating electrical signals of opposite polarity for effecting in-phase contour-mode vibration of the plates while making the arms to vibrate in opposite phase to the plates.

Abstract: A temperature sensor is formed by mounting a force-sensitive resonator on a resilient or non-resilient base structure, preferably in an enclosure such that thermally induced expansions or contractions of the base structure apply a stress to the resonator. The resonant frequency of the resonator is measured to provide an indication of the temperature of the base structure and resonator.

Abstract: The GT-cut quartz resonator resonated by two longitudinal modes and provided with the masses for frequency-temperature characteristics adjustment and frequency adjustment. The frequency-temperature characteristics and the frequency of the GT-cut quartz resonator are adjusted by eliminating the masses. Consequently, the quartz resonator adjusted to the normal frequency and having the excellent frequency-temperature characteristics is attained. Further the GT-cut quartz resonator of small and thin size is attained by making the resonant portion and the supporting portions in one piece by photolithographic technique.

Abstract: A GT-cut quartz resonator mounted on a pedestal is disclosed. The pedestal has a plural though holes on a predetermined positions. The frequency and the frequency-temperature characteristics of the GT-cut quartz resonator are easily adjusted by depositing masses on the resonator by evaporation and sputtering through the through holes on the pedestal.

Abstract: A quartz thermometer which emits a signal, the frequency of which is a substantially linear function of temperature. The thermometer comprises a quartz resonator provided with electrodes disposed on the margins of the upper and lower main surfaces, parallel to the length direction. The electrodes are supplied with electric current so as to cause the resonator to vibrate torsionally. The length of the resonator is substantially parallel to the X axis of the quartz crystal. An electronic circuit is responsive to the signal emitted by the resonator for producing an output representative of temperature.

Abstract: A crystal mounting arrangement is provided which achieves central mounting of the crystal on a substrate while not producing frequency changes in the crystal resulting from substantial differential expansion type stress generated over changes in temperature.

Abstract: A quartz crystal oscillator including a quartz crystal plate defining a tuning fork having a base, two vibratory tines extending from the base and a frame integrally extending from the base and surrounding the tines is provided. The quartz crystal plate is disposed between two cooperating case members in the region of the base and frame. Thin metallic electrodes are disposed on the opposed planar surfaces of the quartz crystal plate. A through-hole or opening is formed in the base region of the vibrator plate for electrically connecting an electrode from one planar surface of the plate to the opposed planar surface for providing two external terminals on one surface case member. The electrical connection through the through-hole or opening is a thin metal film disposed by sputtering or deposition.

Abstract: A stress compensated thickness-shear resonator is of an orientation (yxwl) .phi./.theta. selected from loci of stress compensated orientations provided for both the fast and slow thickness-shear modes of vibration. A stress compensated orientation is used in an oscillator for stable frequency-stress behavior. A stress compensated orientation having large-valued temperature coefficients of frequency is used in a temperature sensor for precision measurements. A stress and temperature compensated orientation is used in a pressure sensor such that the temperature compensated thickness-shear mode is used for pressure measurement while the stress compensated thickness-shear mode is used to compensate for effects of temperature.

Abstract: A miniaturized face-shear mode quartz crystal vibrator and method of manufacture is provided. The vibrator is formed from a Y-cut quartz crystal plate less than 500 .mu.m thick which has been rotated between 45.degree. to 55.degree. about the X-axis. A plurality of vibrators are formed by depositing a thin metallic film on the two opposed planar surfaces of the plate, selectively etching portions of the metallic films and dissolving the uncoated portions of the plate. The metallic films become the vibrator electrode.

Abstract: A crystal resonator features two crystals mounted such that the acceleration sensitivity vector of one crystal is in an antiparallel relationship to the acceleration sensitivity vector of the other crystal. The composite resonator eliminates acceleration-induced frequency shifts for acceleration in all directions.

Abstract: Temperature stable cuts of quartz comprise the families of doubly rotated cuts defined by (YXwlt) 0/27/138, 7/27/135.5, 15/40/40, 15/30/38, 12.5/35/130 and rotational equivalents thereof. It is found that SAW devices may be fabricated on these cuts which demonstrate a very high degree of temperature stability and which have other characteristics consistent with practical usage. The sensitivity of the stability to variations in the propagation direction, corresponding to the angle psi, is such that it is advantageous to fabricate several input-output transducer pairs, each slightly rotated with respect to the others, and to chose the most stable for actual use.

Abstract: A piezoelectric resonator having a rectangular resonator body cut from a piezoelectric crystal in accordance with a rotated X-cut. One of the end faces bounding the major surfaces is intended for mounting, whereas in the vicinity of the other end face an electrode array is arranged. The electrode array in conjunction with the crystal cut have been selected so that a combined resonant mode is generated, comprising an XY' thickness-shear vibration and a thickness vibration in the X or Y' direction.

Abstract: Disc shaped quartz crystal resonators of plano-convex, plano-plano, and bnvex configurations have the b-mode resistance raised relative to the c-mode resistance by the proper choice of mounting geometry, thus suppressing the undesired b-mode in precision oscillator circuits without the use of added circuitry.

Abstract: Doubly rotated quartz crystal blanks such as the SC, IT and FC cuts have ir apparent angles of cut and hence their frequency vs. temperature characteristics modified by changing the contours of one or both of the convex sides thereof, or by changing the electrode areas thereof; or a combination of these two changes.

Abstract: An acceleration resistant crystal resonator is made from a single quartz te that is optically twinned into a left-handed (LH) quartz portion and a right-handed (RH) quartz portion. According to the method, the optically twinned single quartz plate is formed into a resonator plate wherein the effective thickness of the (LH) portion is substantially the same as the effective thickness of the (RH) portion. The resonator plate is then mounted and bonded to the support structure of a crystal resonator enclosure. A pair of electrodes is then deposited onto the (LH) portion and a pair of electrodes deposited onto the (RH) portion. The thickness of the two pairs of electrodes is then adjusted so that the resonant frequency of the resonator on the (LH) portion is substantially the same as the resonant frequency of the resonator on the (RH) portion. The pairs of electrodes are then interconnected to each other and to an oscillator circuit so that in-phase vibration of the two portions is assured.

Abstract: A generally flat, relatively thin AT-cut piezoelectric resonator element structured to minimize the force-frequency effect when mounted and energized in a housing. The resonator is in the form of an equilateral hexagon with the X crystallographic axis of the crystal passing through one set of opposing corners with mounting being effected at an adjacent set of corners respectively .+-.60.degree. away from the X axis which thereby results in a substantially zero frequency shift of the operating frequency.

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: 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: An acceleration resistant crystal features two crystals mounted together h at least two axes of each crystal being in antiparallel relationship with respect to corresponding axes of the other crystals. The two crystals can be chiral pairs and thus have three corresponding axes in antiparallel relationship for acceleration resistance in any arbitrary direction with respect to the crystal axes.

Abstract: A piezoelectric crystal element for use in force and pressure transducers and accelerometers, consisting of a monocrystalline cubic-polar material with electrode faces that intersect one of the crystallographic principal axes X,Y,Z at an angle .alpha.'=arc sin .sqroot.p and the other principal axes at .beta.'=.+-.1/2 arc cos p, wherein p=0 for the piezoelectric orthoaxial shear effect, p=1/3 for the longitudinal piezoeffect and p=1 for the transverse piezoeffect.

Abstract: Cutting a quartz tuning fork crystal vibrator at a preferred angle and with a thickness which establishes a close coupled relationship between the flexural and torsional modes of vibration of the arms or tines produces a vibrator having a highly favorable cubic frequency temperature characteristic at predetermined frequencies. Weight added to the ends of the vibrating tines reduces the frequency of both flexural and torsional vibration, whereas weight added at nodal points in the flexural vibration primarily reduces only the torsional vibrational mode. Accordingly, a wide range of frequency adjustments is possible. Deviations from the desired crystal operating frequency due to manufacturing variances are adjustable by sequential weight modifications while the desirable cubic temperature characteristic is retained. High accuracy over a wide temperature range permits operation in oscillator circuits at relatively low frequencies and with attendant low power consumption.

Abstract: A piezoelectric bi-resonator with electrodes not adhering to the crystal, comprising at least first and second plates in dielectric material on which plates are deposited respectively first and second electrodes, a third plate in dielectric material having faces opposed to the first and second plates respectively, on which faces are respectively deposited third and fourth electrodes, connected together, and a piezoelectric body constituted by two piezoelectric chips made of quartz, independent and similar, one of which is interposed between the said first and third electrodes, without contact therewith, and the other is interposed between the second and fourth electrodes without contact therewith, the said piezoelectric quartz chips being arranged so that their axes Y' are opposite.

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: An external source of electromagnetic energy is applied to quartz in addin to the conventional heating and DC bias electric field. The source can be either coherent or incoherent. The wavelengths can range from the infrared through the visible into the ultraviolet.

Abstract: An AT-cut quartz resonator is disclosed, wherein the length l, the width w and the thickness t of the quartz crystal plate are respectively chosen in the directions of an electrical axis (X-axis), an optical axis (Z'-axis) and a mechanical axis (Y'-axis), the width-to-thickness ratio w/t is chosen in the range of 2.0 to 2.8 and the length-to-thickness ratio l/t is chosen less than 25. Consequently, an AT-cut quartz resonator of miniature size having high Q-values of the major mode and excellent frequency-temperature characteristics of the vibration frequency is realized.

Abstract: A thickness-shear mode piezo-electric vibrator comprises a piezo-electric crystal operable in the thickness-shear mode, driving electrodes formed on opposed surfaces of the crystal, and an addition mass formed on at least one of the driving electrodes and positioned on the nodal line of a 3-fold harmonic vibration so that the frequency f.sub.o of the fundamental main vibration and the frequency f.sub.3s of the 3-fold harmonic vibration always satisfy the following relation within the practical application ranges of temperature and load capacitance; ##EQU1## thereby effectively eliminating or preventing the "abnormal frequency phenomenon" which would otherwise occur due to the 3-fold harmonic vibrations.

Abstract: Quartz is grown from a quartz seed material by depositing electrodes onto the seed, heating the seed to about 500 degrees C. while applying an electric field along the Z-axis of the seed of a strength of about 2 kV/cm for about 72 hours, maintaining the electric field while the seed is cooled to room temperature, removing the electrodes from the cathode surface of the seed, etching the seed, placing the seed in an autoclave and hydrothermally growing quartz.

Abstract: A subminiature flexural mode quartz crystal vibrator comprises a tuning fork formed by photolithographic techniques from a thin quartz crystal plate obtained by rotating an X-cut plate around the X-axis by an angle of 0.degree. to 10.degree. and further rotating the X-cut plate around the Y'-axis by an angle of 70.degree. to 90.degree., the plate having a thickness of less than 0.2 mm. Electrodes formed on sides of the tines are of a different metallic material from planar electrodes formed on at least one of the top and bottom surfaces of the tines. A side electrode of one tine is electrically connected by an overlapping joint with a planar electrode of the other tine.

Abstract: A rectangular AT-cut quartz resonator comprising a quartz crystal plate rotated about 35.degree. around the X-axis, has dimensional ratios w/t and l/t respectively in the range of 3.1 to 3.7 and 14.5 to 16.2, where the length l, width w and thickness t are respectively along the X-axis, Z-axis, and Y-axis.

Abstract: A yzw 35.degree.0' thickness shear crystal bar is provided with bevels cut n its longest narrow surfaces (b, c) proximate the ends in order to obtain energy trapping of the coupled mode vibrations which may arrive at said ends and thus permit shortening of the bar for a given quality factor.

Abstract: A thickness-width shear quartz crystal vibrator, having each vibrating mode (p, q, r) respectively being (1, 1, 1), in which "p" is the number of crests of a sine wave form of polarization directed along its electrical axis, "q" is the number of crests of a cosine waveform of polarization directed along its thickness and "r" is the number of crests of cosine waveform of polarization directed along its width perpendicular to the said electrical axis. The vibrator is cut out from a Y-plate of quartz crystal at the angle between 34 to 36 degrees turned around the X-axis thereof and is provided with plural opposite electrodes on the vertical surface or the surface parallel to the y-axis thereof. Therefore, the said quartz crystal vibrator has a low equivalent impedance and also has an excellent frequency-temperature characteristic.

Abstract: A method which permits highly stable frequency adjustment of piezoelectric crystal devices to tight tolerances. Small fragments of the crystal (10) which resemble conchoidal shells (18) are removed from at least one surface (11) of the crystal plate by fracturing. In one example, this is accomplished by applying pressure from a sharp-pointed stylus (20) near the edge of the plate.

Abstract: Piezoelectric resonator comprising a sealed box in which a vacuum has been formed or into which has been introduced a residual gas, within said box a piezoelectric crystal having first and second main opposite faces, a first metal electrode deposited on the first main face of the crystal and a second metal electrode deposited on the second main and opposite faces of the crystal, a first conductor connected to the first electrode and extending outside the box, a second conductor connected to the second electrode and extending outside the box and means for maintaining the crystal within the box, wherein the piezoelectric crystal comprises a central portion and a peripheral portion forming a ring which spacedly surrounds the central portion and connected to said central portion by an intermediate portion which over at least part of the distance between the central portion and the peripheral portion has a reduced thickness compared with the thickness of said central and peripheral portions wherein the first and s

Abstract: The invention relates to quartz plates. The plate is a plate with double rotation. The angle .phi. lies between 6.degree. and 10.degree.. The angle .theta. lies between -41.degree.45' and -38.degree.55'. The direction of propagation forms an angle of .PSI. with an axis deduced from the electrical axis by the rotation .phi. of the plate and .PSI. lies between 26.degree. and 28.degree.. The angles .phi., .theta. and .PSI. satisfy the equation .phi.-.theta.-.PSI.=21.degree.42'.+-.8'. Application to surface waves.

Abstract: An improved quartz crystal resonator of the type comprising an AT type cut quartz plate is provided in which the plate comprises metallized main electrodes on opposed surfaces thereof which are surrounded by spaced apart metallized supplementary control electrodes. The opposed surfaces of the plate provide a non-metallized unused portion for the plate over a substantial portion of the opposed surfaces. Each of the supplementary control electrodes has at least an associated parameter of width, thickness, density, air gap distance from the respective main electrode and an applied electrode potential and each of the main electrodes has at least an associated corresponding parameter. At least one of the associated parameters of the supplementary electrodes is different from the corresponding associated parameter for the respective main electrodes for controlling the associated Q- factor and frequency of the spurious resonance frequencies.

Abstract: An oscillator circuit including a flexural quartz crystal vibrator of the tuning fork type having an electromechanical coupling factor within the range of 2.5% to 3.5%. The vibrator is comprised of a quartz crystal element including a base portion and a pair of vibratable legs extending therefrom, and a pair of electrodes disposed on the quartz element for receiving alternating electrical signals of opposite polarity for effecting flexural vibration of the legs in response to the electrical signals. The quartz element is defined by a cutting angle within the range of zytw (0.degree.-10.degree.)/(10.degree.-30.degree.).

Abstract: An AT-cut piezoelectric crystal resonator having a plurality of contoured surfaces, two of these contoured surfaces being generated by translating contour lines parallel to the z-axis and perpendicular to the electric axis. At least one of these two surfaces is convex, and another two contoured surfaces are perpendicular to the z-axis and spaced apart by a length dimension z'.sub.0 which is 0.1 to 1.3 of the maximum thickness dimension representing the distance between the first mentioned two surfaces and measured along a line perpendicular to the x-axis. The resonator is adapted for performing a mode of vibration along the thickness forming either a fundamental standing wave or an overtone thereof of a thickness-shear vibration. The free ends of the vibration are positioned at the first mentioned two surfaces, and the amplitude of vibratory displacements appearing along the x-axis is maximum at the center of each surface of the first mentioned two surfaces.

Abstract: A method and apparatus utilizing a quartz crystal resonator with an orientation substantially equal to (yxwl) 21.93.degree./33.93.degree. vibrating simultaneously in two thickness modes to provide a stable frequency signal source. By combining a quartz crystal resonator of the above type with either digital or analog compensation, the frequency-temperature deviation of one of the crystal mode frequencies is used as an internal thermometer and the second crystal mode frequency as a reference frequency signal. The frequency signal for the thermometer function is utilized by the compensation network to stabilize the frequency of the reference signal. Additionally, the analog or digital compensation is accomplished by means of either a curve-fitting routine or an interpolation look-up table routine.

Abstract: An acoustic wave device employing surface skimming bulk waves comprises a piezo electric substrate having a flat surface which carries an input transducer and an output transducer for respectively lanuching and receiving acoustic waves into and from the bulk of the substrate. The substrate may be of quartz, lithium tantalate, or lithium niobate and has the flat surface orientated so that a surface skimming bulk wave is launched without generation of surface acoustic waves.

Abstract: A piezoelectric crystal element comprising a member of monocrystalline material of symmetry class 32 has two force introduction surfaces essentially parallel to a crystallographic `a`-axis but inclined with respect to the `c`-axis so as to intersect the latter at a specific angle e.g. 10.degree. to 40.degree. to considerably reduce over a desired temperature range the temperature dependence of transverse of antiaxial shear sensitivity.

Abstract: Quartz resonator with electrodes that do not adhere to the crystal. Quartz resonator having improved medium-term and long-term stabilities and permitting easier placing on frequency. The resonator comprises, inside a tight housing 1, a condenser formed by two disks 3, 4 made of a dielectric material and separated by a removable ring 2 which determines the spacing between the disks 3 and 4. Electrodes are formed by metallization on the faces of the disks 3 and 4 located opposite a quartz crystal 1 enclosed in said condenser. The spacings between the crystal 1 and the disks 3 and 4 are considerably less than 1 millimeter. Application, for example, in the fields of telecommunications and radars.

Abstract: The invention relates to piezoelectric resonators, and more particularly to piezoelectric resonators comprising a DT- or CT-cut quartz plate vibrating torsionally about its longitudinal axis which is the electrical axis X of the quartz crystal. The width of the plate b, extending along the Z'-axis, and its thickness h extending along the Y'-axis are linked by the relation1<b/h<10In proportion to its size, the resonator has a low resonance frequency, the temperature coefficient of the first order of which is nil and the temperature coefficient of the second order of which is very low.

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: A flexural mode tuning fork quartz crystal vibrator having two vibrator tines including first and second opposed substantially planar surfaces, the thickness of the plate between said opposed surfaces being no greater than 0.2 mm is provided. Both surfaces of each tine have three electrodes photo-etched on at least the lengthwise peripheral sides of the respective surfaces of the tines and a third electrode photo-etched intermediate and not in contact with the two peripherally disposed electrodes with each intermediate electrode being short-circuited to the peripheral electrode on the other tine. A fourth electrode is disposed on at least one lengthwise side edge of both of the respective tines, the fourth electrode electrically coupling the peripherally disposed electrode on the lengthwise peripheral sides of the respective surfaces of the tine.

Abstract: Heating electrode means provided directly on a quartz vibrator body in a specific angular range does not effect on the change in the resonant frequency which is normally to be caused by direct heating of the body so that a highly stable piezoelectric quartz vibrator can be provided without a constant temperature box.

Abstract: A method and apparatus utilizing a quartz crystal resonator with an orientation substantially equal to (yxwl) 21.93.degree./33.93.degree. vibrating simultaneously in two thickness modes to accurately measure temperature and unknown frequencies or to provide a stable frequency signal source. By combining a quartz crystal resonator of the above type with either digital or analog compensation, the frequency-temperature deviation of one of the crystal mode frequencies is used as an internal thermometer and the second crystal mode frequency as a reference frequency signal. The frequency signal for the thermometer function is utilized by the compensation network to correct the measurements made with, or to stabilize, the frequency of the reference frequency signal. Additionally, the analog or digital compensation is accomplished by means of either a curve-fitting routine or an interpolation look-up table routine.

Abstract: A multiple resonator or filter is described in the form of a rectangular of piezoelectric material having dimensional ratios selected so as to assure vibration in a thickness shear mode strongly coupled with a flexural mode. At least two energy trapping zones are provided extending over the entire width of the bar. The arrangement enables achievement of a high quality factor combined with extremely small dimensions.

Abstract: This specification describes a rectangular quartz crystal which has been igned with specific length-width-thickness ratios whereby vibration takes place in the thickness shear mode strongly coupled with flexural vibrations. The choice of the specific ratios permits an improved performance insofar as dynamic capacitance range, temperature dependent variations of frequency and finally quality factor are concerned. The dimensions and proportions make the crystal suitable for use as a high frequency time piece resonator.

Abstract: A thickness-shear crystal vibrator having a pair of driving electrodes on a pair of opposed planar surfaces. A pair of side surfaces adjacent the opposed surfaces has a pair of electrode leads disposed thereon which extend from the driving electrodes to the thickness center line or shear vibration modal line of the vibrator. The electrode leads are formed to extend over a bevel cut at the edge portion of the opposed side planar surfaces and ends of the electrode leads are both connected to a respective conductive supporting member.