Air Gap Patents (Class 310/349)
  • Patent number: 6710681
    Abstract: An apparatus having both a resonator and an inductor fabricated on a single substrate and a method of fabricating the apparatus are disclosed. The apparatus includes a resonator and an inductor that is connected to the resonator. Both the resonator and the inductor are fabricated over their respective cavities to produce a high Q-factor filter circuit.
    Type: Grant
    Filed: July 13, 2001
    Date of Patent: March 23, 2004
    Assignee: Agilent Technologies, Inc.
    Inventors: Domingo A. Figueredo, Richard C. Ruby, Yury Oshmyansky, Paul Bradley
  • Publication number: 20040027216
    Abstract: A film bulk acoustic resonator may be formed with a piezoelectric film having improved quality. The piezoelectric film may be deposited directly onto a single crystal silicon substrate. That substrate may be removed and selectively replaced with a lower electrode to form the film bulk acoustic resonator.
    Type: Application
    Filed: August 8, 2002
    Publication date: February 12, 2004
    Inventors: Qing Ma, Li-Peng Wang, Valluri Rao
  • Publication number: 20040021529
    Abstract: A thin-film resonator having a protective layer and a method of making the same are disclosed. The resonator has a bottom electrode, piezoelectric layer, a top electrode, and protective layer. The protective layer covers the top electrode to protect the top electrode from air and moisture. A protective underlayer can be used to protect the bottom electrode from air and moisture. The protective underlayer can also serve as a seed layer to assist in fabrication of high quality piezoelectric layer.
    Type: Application
    Filed: July 30, 2002
    Publication date: February 5, 2004
    Inventors: Paul D. Bradley, Yury Oshmyansky, Richard C. Ruby
  • Patent number: 6628178
    Abstract: The surface acoustic wave elements and the other surface mounting elements are mounted on a ceramic multi-layer substrate. The surface acoustic wave elements may be flip chips face-down-bonded to the gold coated mounting electrodes of the multi-layer ceramic substrate by gold-to-gold bonding. At least the surface acoustic wave elements are covered as sealed airtight with the side walls fixed to the multi-layer ceramic substrate and a cover closing the opening of the side walls.
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: September 30, 2003
    Assignee: TDK Corporation
    Inventor: Fumio Uchikoba
  • Patent number: 6483229
    Abstract: A method for fabricating a resonator, and in particular, a thin film bulk acoustic resonator (FBAR), and a resonator embodying the method are disclosed. An FBAR is fabricated on a substrate by mass loading piezoelectric (PZ) layer between two electrodes. For a substrate having multiple resonators, only selected resonator is mass loaded to provide resonators having different resonance frequencies on the same substrate.
    Type: Grant
    Filed: March 5, 2001
    Date of Patent: November 19, 2002
    Assignee: Agilent Technologies, Inc.
    Inventors: John D. Larson, III, Paul D. Bradley, Richard C. Ruby
  • Patent number: 6424237
    Abstract: A bulk acoustic resonator having a high quality factor is formed on a substrate having a depression formed in a top surface of the substrate. The resonator includes a first electrode, a piezoelectric material and a second electrode. The first electrode is disposed on the top surface of the substrate and extends beyond the edges of the depression by a first distance to define a first region therebetween. The piezoelectric material is disposed on the top surface of the substrate and over the first electrode, and the second electrode is disposed on the piezoelectric material. The second electrode includes a portion that is located above the depression. The portion of the second electrode that is located over the depression has at least one edge that is offset from a corresponding edge of the depression by a second distance to define a second region therebetween. The first and second regions have different impedances, as a result of the different materials located in the two regions.
    Type: Grant
    Filed: December 21, 2000
    Date of Patent: July 23, 2002
    Assignee: Agilent Technologies, Inc.
    Inventors: Richard C. Ruby, John D. Larson, III, Paul D. Bradley
  • Patent number: 6380662
    Abstract: A compact quartz oscillator includes a quartz vibrator that is integrally mounted on a circuit substrate. In the quartz oscillator, flux residue can be easily washed away. A cavity is defined in the approximate center of the circuit substrate. Within the cavity, circuit components defining an oscillation circuit, a temperature-compensating circuit, and other such circuits are surface-mounted preferably via reflow soldering. Connection electrodes are disposed at the four corners of walls surrounding the cavity. The connection electrodes are bonded to electrodes of the quartz vibrator mounted on the circuit substrate preferably via reflow soldering. Recesses are provided in the top surfaces of the walls. With the recesses, clearances are created between the circuit substrate and the quartz vibrator. As a result, in order to wash away flux residue.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: April 30, 2002
    Assignee: Murata Manufacturing Co., LTD
    Inventors: Toshikazu Funahara, Akiyoshi Moriyasu, Tadashi Kani, Makoto Fujita
  • Patent number: 6366005
    Abstract: A tuning fork type vibrator including two arms and a base is supported by a supporting substrate mounted on a stem, and an oscillation limiting member formed from a ring-shaped rubber-like elastic body is mounted with its one face secured to the stem so as to surround the base. When an external vibration or impact is applied, the tuning fork type vibrator oscillates in response to the vibration or impact, but the oscillation range of the tuning fork type vibrator is limited by the presence of this oscillation limiting member, and thus bumping of the tuning fork type vibrator against the surrounding members such as the stem is prevented. Moreover, a gyro characteristic is not impaired, and a loss of the gyro function due to a stop of drive vibration does not occur.
    Type: Grant
    Filed: December 22, 2000
    Date of Patent: April 2, 2002
    Assignees: Fujitsu Limited, Fujitsu Media Devices Limited
    Inventors: Hiroshi Ishikawa, Masanori Yachi, Yoshio Satoh, Kazutsugu Kikuchi, Yoshitaka Takahashi
  • Publication number: 20010040420
    Abstract: A piezoelectric transformer includes an output part having laminated sheets formed of a first piezoelectric material and one or more input parts, each having laminated sheets made of a second piezoelectric material. The piezoelectric strain constant of the second piezoelectric material is greater than that of the first piezoelectric material.
    Type: Application
    Filed: March 30, 2001
    Publication date: November 15, 2001
    Applicant: Taiyo Yuden Co., Ltd.
    Inventors: Yoshiyuki Watanabe, Hiroshi Kishi, Yasuyuki Inomata, Shigeo Ishii, Mitsuya Tsujikawa
  • Patent number: 6204593
    Abstract: A resonator including a piezoelectric element; a lead terminal comprised of an electroconductive wire material formed by press working with a tapered receiving groove for holding an end of the piezoelectric element at its top end; and a capacitor connected to the outer circumference of the top end of the lead terminal in a state with the end of the piezoelectric element held in the receiving groove of the lead terminal so as to constitute a resonance circuit together with the piezoelectric element. Preferably, a difference of a coefficient of heat expansion of a piezoelectric ceramic constituting the piezoelectric element and a coefficient of heat expansion of a dielectric ceramic constituting the capacitor is not more than 5 ppm/° C. Preferably, the area of the surface of the piezoelectric element contacting a vibrating space is in a predetermined relation with the frequency band of the piezoelectric element.
    Type: Grant
    Filed: August 2, 1999
    Date of Patent: March 20, 2001
    Assignee: TDK Corporation
    Inventors: Touru Takahashi, Yuuichi Sugawara
  • Patent number: 6064282
    Abstract: A piezoelectric filter has a significantly reduced size and a sufficient coupling capacitance while avoiding an uneven outer configuration of an overall shape of the filter. The piezoelectric filter includes a first resonating unit and a second resonating unit and a coupling capacitance unit disposed in a piezoelectric substrate. The coupling capacitance unit is provided with a first coupling capacitance electrode located on an upper surface of the piezoelectric substrate and a second coupling capacitance electrode located on a lower surface thereof and the first and second coupling capacitance electrodes are arranged to extend to side edge surfaces of the piezoelectric substrate.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: May 16, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Tomoaki Futakuchi, Kunio Sawai, Taketoshi Hino
  • Patent number: 6060818
    Abstract: An acoustical resonator and a method for making the same. A resonator according to the present invention includes a layer of piezoelectric material sandwiched between first and second electrodes. The first electrode includes a conducting sheet having a RMS variation in height of less than 2 .mu.m. The resonator bridges a cavity in a substrate on which the resonator is constructed. The resonator is constructed by creating a cavity in the substrate and filling the same with a sacrificial material that can be rapidly removed from the cavity after the deposition of the various layers making up the resonator. The surface of the filled cavity is polished to provide a RMS variation in height of less than 0.5 .mu.m. The first electrode is deposited on the polished surface to a thickness that assures that the RMS variation in height of the metallic layer is less than 2 .mu.m. The piezoelectric layer is deposited on the first electrode and the second electrode is then deposited on the piezoelectric layer.
    Type: Grant
    Filed: June 2, 1998
    Date of Patent: May 9, 2000
    Assignee: Hewlett-Packard Company
    Inventors: Richard C. Ruby, Yogesh Desai, Donald R. Bradbury
  • Patent number: 6011451
    Abstract: A chip type filter reduces a required mount space while facilitating achievement of impedance matching and also enhancing the stability of filter characteristics. The chip type filter includes a first piezoelectric substrate, a filter section with resonance electrodes, a common electrode and a coupling capacitance section, a second piezoelectric substrate, a second filter section with a pair of resonance electrodes, a common electrode opposing the electrodes in a "top/bottom-surface overlap" relationship and a coupling capacitance section. The filter is arranged such that the first and second piezoelectric substrates are adhered to each other with an adhesive layer located therebetween.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: January 4, 2000
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Masao Gamo
  • Patent number: 6002308
    Abstract: A piezoelectric filter is arranged to suppress unnecessary vibrations caused by wiring patterns such as lead-out electrodes to improve filter characteristics. The filter includes a filter section having a pair of resonant electrodes located on an upper surface of a piezoelectric substrate, and a common electrode located on the lower surface of the substrate so as to be opposite to the resonant electrodes. A capacitor connected to the filter section includes a capacitive electrode having the function of a lead-out electrode and located on the upper surface of the piezoelectric substrate, and another capacitive electrode located on the lower surface of the piezoelectric substrate. Lead-out electrodes extend to edges of the piezoelectric substrate. The piezoelectric substrate is unpolarized in a region where at least a portion of the lead-out electrodes is located and in a vicinity of this region.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: December 14, 1999
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Masao Gamo
  • Patent number: 5982077
    Abstract: An insulating substrate (1) is a laminate of a first insulating substrate (1a) and a second insulating substrate (1b) on which wires and electrodes are formed previously. In this case a concavity is formed on the insulating substrate (1) by a hollow part (4) of the first insulating substrate (1a) and an upper surface of the second insulating substrate. Metallic wires are also arranged on an area corresponding to a bottom surface of the concavity of the second insulating substrate. As a result, space for arranging metallic wires expands and a space between metallic wires can be widened. Further, metallic wires which bypass areas corresponding to external electrodes formed on a lower surface of the second insulating substrate can be formed. This results in smaller stray capacitance between an electrode and a wire and between wires.
    Type: Grant
    Filed: July 3, 1997
    Date of Patent: November 9, 1999
    Assignees: Miyota Co., Ltd., Citizen Watch Co., Ltd.
    Inventors: Toshinori Ide, Hisao Wakabayashi
  • Patent number: 5949305
    Abstract: In a ceramic package for encapsulating a SAW (surface acoustic wave) filter, a metal pad is formed on the bottom of a recess formed in the package. A SAW filter chip is mounted to the package such that propagation paths formed on the chip face the bottom of the recess with the intermediary of a gap. The gap promotes easy impedance adjustment.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: September 7, 1999
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Hajime Shimamura
  • Patent number: 5945774
    Abstract: An improved crystal oscillator package is described in which the crystal oscillators are attached to ceramic substrates by means of connectors, formed from materials such as silver-platinum and silver, using thick film techniques. An optional opening in the substrate allows a liquid or gaseous medium to make easy contact with the oscillator chips' electrodes on which a biosensitive film of a specific receptor has been deposited, thereby allowing the crystals to act as detectors. In the case of the multi-oscillator module, several different detectors may be present in the same unit.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: August 31, 1999
    Assignee: Industrial Technology Research Institute
    Inventors: Ming-Chang Shih, Kuo-Chuan Chen
  • Patent number: 5910756
    Abstract: There is provided a Bulk Acoustic Wave Resonator-Stacked Crystal Filter (BAWR-SCF) filtering circuit or device. The BAWR-SCF circuit comprises a first pair of ports, a second pair of ports, a first lead that is connected between a first and a second one of the first pair of ports, and a second lead that is connected between a first and a second one of the second pair of ports. The BAWR-SCF circuit also comprises a first BAW resonator connected in series in the first lead, and a second BAW resonator connected between the first and second leads. The BAWR-SCF further comprises a Stacked Crystal Filter (SCF) having first and second terminals connected in the first lead between the first BAW resonator and the second one of the first pair of ports. The SCF also has a third terminal that is connected to a node of the second lead.
    Type: Grant
    Filed: May 21, 1997
    Date of Patent: June 8, 1999
    Assignee: Nokia Mobile Phones Limited
    Inventor: Juha Ella
  • Patent number: 5780958
    Abstract: A piezoelectric vibrating device is disclosed. The device includes a case having a first compartment with a first compartment height. A bender element, fabricated from an piezoelectric material, is disposed within the first compartment. A motion limiter is disposed within the case for preventing damage to the bender. The motion limiter has a first portion that abuts against the case to prevent the first compartment height from compressing beyond a predetermined first compartment minimal height. The device further includes electronic controls for providing a signal to the bender element. The electronic controls further include an optimal wave form signal generator. The wave form may also be a square wave, pulse train, truncated wave or other type of wave depending on each particular application.
    Type: Grant
    Filed: November 3, 1995
    Date of Patent: July 14, 1998
    Assignee: Aura Systems, Inc.
    Inventors: Michael G. Strugach, Andrei Szilagyi
  • Patent number: 5722303
    Abstract: A mixed-mu superconducting bearing including a ferrite structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet structure. The ferrite structure is levitated by said stationary permanent magnet structure.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: March 3, 1998
    Assignee: University of Chicago
    Inventors: John R. Hull, Thomas M. Mulcahy
  • Patent number: 5640887
    Abstract: A flywheel energy storage device including an iron structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet. The stationary permanent magnet levitates the iron structure while the superconductor structure can stabilize the rotating iron structure.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 24, 1997
    Assignee: University of Chicago
    Inventors: John R. Hull, Thomas M. Mulcahy, Kenneth L. Uherka
  • Patent number: 5604667
    Abstract: An opening is formed in a region of a circuit board opposite a vibration region E of a piezoelectric element. The piezoelectric element is mounted to the circuit board, and electrical connections extend between and support the piezoelectric element from the circuit board by a solder. The soldered connection portions are surrounded by a bonding agent. An opening in the circuit board prevents any excess bonding agent from invading the vibration region E of the piezoelectric element, and the bonding agent assists in dispersing stresses exerted on the circuit board thereby minimizing the stresses transferred to the piezoelectric element.
    Type: Grant
    Filed: June 30, 1995
    Date of Patent: February 18, 1997
    Assignee: Murata Mfg. Co., Ltd.
    Inventor: Ryoichi Morimoto
  • Patent number: 5596239
    Abstract: A high quality factor resonator (15) including a substrate (110) and a resonator layer (150). The resonator layer includes a first electrode (157). The resonator layer (150) is disposed on a surface of the substrate (110). The first electrode (157) is disposed on a distal surface of the resonator layer (150). A cavity (120) is disposed between the substrate (110) and the resonator layer (150) and a second electrode (159) is disposed on the substrate (110) and on a surface of the cavity (120) remote from the resonator layer (150) and is separated from the resonator layer (150) by a thin gap.
    Type: Grant
    Filed: June 29, 1995
    Date of Patent: January 21, 1997
    Assignee: Motorola, Inc.
    Inventor: Michael Dydyk
  • Patent number: 5548178
    Abstract: A piezoelectric vibrator includes a thin quartz plate portion for generating vibrations, and non-contact electrodes for applying an alternating electric field. The electrodes are arranged on opposing sides of the thin quartz plate portion so as to not contact with the thin quartz plate portion. The electrodes may be formed on a supporter which can be bonded directly to the thin quartz plate. The electrodes may also be formed above the thin quartz plate and supported by the plate outside the thin quartz plate portion. The piezoelectric vibrator has a superior Q of resonance at high frequencies.
    Type: Grant
    Filed: April 19, 1995
    Date of Patent: August 20, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazuo Eda, Takashi Nagata
  • Patent number: 5540116
    Abstract: A flywheel energy storage device including an iron structure disposed for rotation adjacent a stationary superconductor material structure and a stationary permanent magnet. The stationary permanent magnet levitates the iron structure while the superconductor structure can stabilize and levitate the rotating iron structure.
    Type: Grant
    Filed: March 3, 1993
    Date of Patent: July 30, 1996
    Assignee: University of Chicago
    Inventors: John R. Hull, Thomas M. Mulcahy, Kenneth L. Uherka
  • Patent number: 5449965
    Abstract: An oscillator has a pair of upper and lower casing members in the form of plates, and a vibration plate pinched between the upper and lower casing members. A tongue-like vibrating portion is formed by forming a slit in the vibration plate inside an outer peripheral portion of the vibration plate pinched between the upper and lower casing members. Electrodes are formed on obverse and reverse surfaces of the vibrating portion.
    Type: Grant
    Filed: October 13, 1993
    Date of Patent: September 12, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Yoshikazu Tsuru
  • Patent number: 5406230
    Abstract: A chip type oscillator which comprises two oscillator elements bonded to each other, and two protective plates bonded to the outer surfaces of the oscillator elements. The oscillator elements have lead electrodes which are provided on corner portions thereof and are connected with vibrating electrodes, and the protective plates have external electrodes which are provided on corner portions thereof. The external electrodes and the lead electrodes are independently connected with each other through conductive coatings provided on peripheral surfaces of the oscillator chip. Integrated load capacitors may also be formed on the oscillator chip. The two oscillator elements are so integrated with each other that it is possible to reduce the number of components as well as the packaging area and simplify the mounting operation.
    Type: Grant
    Filed: February 24, 1993
    Date of Patent: April 11, 1995
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Takashi Yamamoto
  • Patent number: 5359494
    Abstract: An opening 11 is formed in a region of a circuit board 10 opposite to a vibration region E of a piezoelectric element 5. The piezoelectric element 5 is mounted on the circuit board 10, and electrode connection portions 9 of the piezoelectric element 5 are connected with and fixed to the circuit board by a solder. In succession, soldered connection portions kept away from the vibration region E of the piezoelectric element 5 are filled with a bonding agent 8. Thereupon, an excess bonding agent 8 with which the soldered connection portions are filled is eliminated by the opening 11, and hence is prevented from invading the vibration region E of the piezoelectric element 5. Further, any stress exerted on the circuit board 10 is dispersed because of its being mostly received by the bonding agent 8, and hence any stress exerted on the piezoelectric element 5 is reduced.
    Type: Grant
    Filed: October 8, 1993
    Date of Patent: October 25, 1994
    Assignee: Murata Mfg. Co., Ltd.
    Inventor: Ryoichi Morimoto
  • Patent number: 5235238
    Abstract: Herein disclosed is a device for determining the concentration of a substance in a solution by making use of a quartz oscillator. In the device, at least one of a plurality of electrodes for applying an electrical voltage to a crystal wafer is separated from the crystal wafer, and the space between the separated electrode and the crystal wafer is filled with a conductive substance. The electrode-separated piezoelectric crystal oscillator thus obtained can be made more highly accurate, smaller-sized and more inexpensive.
    Type: Grant
    Filed: February 7, 1992
    Date of Patent: August 10, 1993
    Assignee: Dainabot Company, Limited
    Inventors: Toshiaki Nomura, Tohru Yamada
  • Patent number: 5198716
    Abstract: A micro-machined resonator, typically quartz, with upper and lower micro-machinable support members, or covers, having etched wells which may be lined with conductive electrode material, between the support members is a quartz resonator having an energy trapping quartz mesa capacitively coupled to the electrode through a diaphragm; the quartz resonator is supported by either micro-machined cantilever springs or by thin layers extending over the surfaces of the support. If the diaphragm is rigid, clock applications are available, and if the diaphragm is resilient, then transducer applications can be achieved. Either the thin support layers or the conductive electrode material can be integral with the diaphragm. In any event, the covers are bonded to form a hermetic seal and the interior volume may be filled with a gas or may be evacuated. In addition, one or both of the covers may include oscillator and interface circuitry for the resonator.
    Type: Grant
    Filed: December 9, 1991
    Date of Patent: March 30, 1993
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Ned A. Godshall, Dale R. Koehler, Alan Y. Liang, Bradley K. Smith
  • Patent number: 4906886
    Abstract: An ultrasound sensor is used for measuring the sound pressure amplitude in the focal range of focused ultrasound shock waves. The sensor contains a polymer foil which is piezoelectrically activated in one region and is coupled to electrodes which are physically separated from the region. The polymer foil is arranged in a hollow plastic cylinder with its flat surface sides parallel to the central longitudinal axis of the hollow cylinder. By this measure, interfering diffraction effects are reduced and miniaturization of the ultrasound sensor is achieved.
    Type: Grant
    Filed: March 8, 1989
    Date of Patent: March 6, 1990
    Assignee: Siemens Aktiengesellschaft
    Inventors: Fritz Breimesser, Bernd Granz, Bertram Sachs
  • Patent number: 4845397
    Abstract: Apparatus is provided for mounting an electronic component having a pressure sensitive active area, which apparatus permits the component to expand and contract with changes in temperature and which does not introduce stresses into the active area of the component. The apparatus includes a cradle which, when attached to a substrate, forms a partial enclosure of the component but which leaves the active area unobscured. A packaging system is also provided wherein the bottom of the cavity of the lower portion of a standard integrated circuit package forms the substrate to be used in conjunction with the cradle for containing the electronic component.
    Type: Grant
    Filed: March 24, 1986
    Date of Patent: July 4, 1989
    Assignee: Tektronix, Inc.
    Inventors: Geoffrey C. Herrick, Emmanuel Sang
  • Patent number: 4782910
    Abstract: A bender acoustic transducer has a flat, piezoelectric element affixed to a flat, elongated inert element. The ends of the inert element are hinged on a supporting rectangular frame which has a rectangular opening. Two sides of the elements are exposed so that when a voltage is applied, a dipole acoustic wave is generated by the transducer.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: November 8, 1988
    Assignee: Mobil Oil Corporation
    Inventor: Claude C. Sims
  • Patent number: 4782469
    Abstract: The ultrasound sensor (2) of the invention comprises a polymer foil (4) which is supported in its outer region and is piezoelectrically activated at least in one portion (42). The portion (42) is coupled electrically to a first electrode (200) in the form of an adjacent, i.e., touching pin. A second electrode (8), in the form of a grid (214) connected to ground and/or a ring (216) connected to ground, is physically separated from the activated portion (42). The pin (200) is connected to the first input of an amplifier (210). The second input thereof is connected to ground. The metallic take-off at the activated zone (42) results in high sensitivity of the ultra-sound sensor (2) which is provided particularly for the measurement of shock waves with a high pressure amplitude and which finds application in lithotripsy.
    Type: Grant
    Filed: October 30, 1987
    Date of Patent: November 1, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventors: Bernd Granz, Georg Naser, Helmut Reichenberger
  • Patent number: 4734611
    Abstract: The invention concerns an ultrasonic sensor (24) in which a polymer foil (4) supported in its peripheral area is piezoelectrically activated at least in a partial section (42). The partial section (42) is electrically coupled to electrodes (8). According to the invention, the electrodes (8), which produce an electrical signal in cooperation with this partial section (42) in response to an ultrasonic wave and are spatially separated from the piezoelectrically active section (42). Because of this feature, the ultrasonic sensor (24) can be used also for measuring ultrasonic shock waves with a high pressure amplitude, since an electrically conductive layer for receiving the electrical signal located on the flat sides of the polymer foil (4) in the piezoelectrically active section (42), is no longer needed.
    Type: Grant
    Filed: December 4, 1986
    Date of Patent: March 29, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventor: Bernd Granz
  • Patent number: 4714904
    Abstract: A magnetostatic wave device unit in which the magnetic biasing unit includes a carrier member which contains one of the pole pieces and forms an enlarged mechanical and electrical support surface for a magnetostatic wave device.
    Type: Grant
    Filed: November 5, 1986
    Date of Patent: December 22, 1987
    Assignee: ITT Aerospace Optical
    Inventor: David A. Willems
  • Patent number: 4626732
    Abstract: A piezoelectric resonator including a base, two conducting posts which pass through the base and a piezoelectric plate. The plate includes a central active zone which is surrounded by a peripheral zone. The two zones are connected by at least two bridges which define slits which separate the central zone from the peripheral zone. Each face of the central zone is covered with an adherent electrode which extends over one of the bridges to a part of the peripheral zone. Each of the electrodes is connected to one of the conducting posts through a conductive metal ribbon. Each of the metal ribbons bear on the inner part of the peripheral zone so that the ribbon is disposed substantially as an extension of the corresponding posts.
    Type: Grant
    Filed: March 27, 1985
    Date of Patent: December 2, 1986
    Assignee: Compagnie d'Electronique et de Piezo-Electricite C.E.P.E.
    Inventors: Andre Debaisieux, Jean P. Aubry
  • Patent number: 4558248
    Abstract: A temperature-compensated quartz oscillator having a first plate of quartz that carries a first electrode which displays a sensitivity to temperature that exceeds that of the piezoelectric quartz wafer which comprises a first resonator which vibrates at a reference frequency f.sub.M. The first plate cooperates with the first electrode and a third electrode to form a second quartz resonator. Means for applying to the first and third electrodes an excitation electric power to drive the active portion of the first plate according to a mode which is sensitive to temperture, at a frequency f.sub.T close to, but slightly different from, the reference frequency f.sub.M. Means for comparing, which enable comparison of signals at the terminals of the second and third electrodes, and control means for the regulating means for applying an excitation electric power from the active portion of the piezoelectric wafer.
    Type: Grant
    Filed: May 2, 1984
    Date of Patent: December 10, 1985
    Assignee: Etat Francais
    Inventor: Jean P. Valentin
  • Patent number: 4464598
    Abstract: A quartz resonator drawer is housed in a monolithic block cabinet made of quartz. Air gap electrodes are provided on interior walls of the cabinet. The resonator drawer can be removed from the cabinet without dissemblying the electrodes or the cabinet.
    Type: Grant
    Filed: November 19, 1981
    Date of Patent: August 7, 1984
    Assignee: L'Etat Francais
    Inventors: Raymond J. C. Besson, Pierre C. Maitre
  • Patent number: 4334168
    Abstract: An autothermostatic high frequency oscillator comprising a piezoelectric resonator of the type having electrodes which are not adhered to the crystal. The contact between the part of the crystal 1 serving to support the vibrating part of the crystal and the dielectric plates 2,3 supporting the excited electrodes is limited to a discontinuous surface of reduced scope constituted by a finite number of elements of contact surface. At least an infra-red reflector screen (200) located at the very interior of the water tight cavity (400) surrounding the resonator is situated immediately adjacent said resonator and the electric power applied to the excited electrodes is at least in the range of about 50 microwatts. The invention permits one to achieve oscillators with small consumption of energy and high stability.
    Type: Grant
    Filed: July 8, 1980
    Date of Patent: June 8, 1982
    Assignee: Etat Francais
    Inventors: Raymond J. Besson, Jean P. Valentin
  • Patent number: 4135108
    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.
    Type: Grant
    Filed: January 14, 1977
    Date of Patent: January 16, 1979
    Assignee: L'Etat Francais represente par le Delegue Ministeriel
    Inventor: Raymond J. Besson