Patents by Inventor Tohru Yanagisawa

Tohru Yanagisawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8663487
    Abstract: The invention is directed to the provision of a method for manufacturing a crystal oscillator manufacturing method that can achieve a highly precise fine adjustment without applying unnecessary external force to a crystal oscillator, and that can adjust a plurality of crystal oscillators in a collective manner. More specifically, the invention provides a method for manufacturing a crystal oscillator includes a first etching step for forming a prescribed external shape, an electrode forming step for forming an electrode at least in a portion of a surface of the external shape, a leakage amount measuring step for measuring leakage amount associated with leakage vibration of the external shape, and a second etching step for etching the external shape by an amount that is determined based on a measurement result of the leakage amount measuring step so as to adjust balance.
    Type: Grant
    Filed: October 16, 2009
    Date of Patent: March 4, 2014
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Akiko Katoh, Tohru Yanagisawa
  • Patent number: 8037755
    Abstract: A physical quantity sensor 1 comprises a driving circuit 4 that drives a sensor element based on a reference signal; the sensor element 3 that is driven by the driving circuit 4 to convert an externally applied physical quantity to an electrical signal; and an amplifier circuit 5 that amplifies an output signal of the sensor element 3. The driving circuit 4 controls a driving signal, which drives the sensor element, based on the reference signal so that the driving signal is at a fixed level, and the amplifier circuit 5 has a gain characteristic that amplifies the output signal in a direction reverse to a direction in which the reference signal varies or the driving signal of the driving circuit varies. This configuration allows the physical quantity sensor to reduce output level variations in the sensor output against signal level variations in the reference signal and to make the sensitivity constant.
    Type: Grant
    Filed: September 21, 2007
    Date of Patent: October 18, 2011
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Yoichi Nagata, Tohru Yanagisawa
  • Publication number: 20110163063
    Abstract: The invention is directed to the provision of a method for manufacturing a crystal oscillator manufacturing method that can achieve a highly precise fine adjustment without applying unnecessary external force to a crystal oscillator, and that can adjust a plurality of crystal oscillators in a collective manner. More specifically, the invention provides a method for manufacturing a crystal oscillator includes a first etching step for forming a prescribed external shape, an electrode forming step for forming an electrode at least in a portion of a surface of the external shape, a leakage amount measuring step for measuring leakage amount associated with leakage vibration of the external shape, and a second etching step for etching the external shape by an amount that is determined based on a measurement result of the leakage amount measuring step so as to adjust balance.
    Type: Application
    Filed: October 16, 2009
    Publication date: July 7, 2011
    Applicant: CITIZEN HOLDINGS CO., LTD.
    Inventors: Akiko Katoh, Tohru Yanagisawa
  • Patent number: 7771850
    Abstract: An electromagnetic wave shielding laminate comprising a transparent substrate and an electromagnetic wave shielding film formed thereon, characterized in that the electromagnetic wave shielding film has, sequentially from the substrate side, a first high refractive index layer made of a material having a refractive index of at least 2.0, a first oxide layer containing zinc oxide as the main component, an electroconductive layer containing silver as the main component, and a second high refractive index layer made of a material having a refractive index of at least 2.0.
    Type: Grant
    Filed: September 2, 2008
    Date of Patent: August 10, 2010
    Assignee: Asahi Glass Company, Limited
    Inventors: Tohru Yanagisawa, Tamotsu Morimoto
  • Publication number: 20100116052
    Abstract: At the frequency of natural vibration with which the driving tines and detection tine of a piezoelectric vibrator resonate, the vibration directions of natural vibrations and the frequency difference between the resonance frequencies are set to reduce the leakage of vibration from the driving tines to the detection tine for suppressing the leakage vibration of the piezoelectric vibrator. In the piezoelectric vibrator, the vibration direction of the driving tines is made orthogonal to the vibration direction of the detection tine, or the frequency difference between the resonance frequency of the driving tines in the in-plane direction and the resonance frequency of the driving tines in the out-of-plane direction is increased sufficiently to suppress the growth of the leakage vibration. This configuration makes the piezoelectric vibrator compact and reduces leakage vibrations.
    Type: Application
    Filed: March 19, 2008
    Publication date: May 13, 2010
    Applicant: CITIZEN HOLDINGS CO., LTD.
    Inventors: Tohru Yanagisawa, Izumi Yamamoto
  • Publication number: 20100039094
    Abstract: A physical quantity sensor 1 comprises a driving circuit 4 that drives a sensor element based on a reference signal; the sensor element 3 that is driven by the driving circuit 4 to convert an externally applied physical quantity to an electrical signal; and an amplifier circuit 5 that amplifies an output signal of the sensor element 3. The driving circuit 4 controls a driving signal, which drives the sensor element, based on the reference signal so that the driving signal is at a fixed level, and the amplifier circuit 5 has a gain characteristic that amplifies the output signal in a direction reverse to a direction in which the reference signal varies or the driving signal of the driving circuit varies. This configuration allows the physical quantity sensor to reduce output level variations in the sensor output against signal level variations in the reference signal and to make the sensitivity constant.
    Type: Application
    Filed: September 21, 2007
    Publication date: February 18, 2010
    Applicant: Citizen Holdings Co., Ltd.
    Inventors: Yoichi Nagata, Tohru Yanagisawa
  • Publication number: 20090004492
    Abstract: An electromagnetic wave shielding laminate comprising a transparent substrate and an electromagnetic wave shielding film formed thereon, characterized in that the electromagnetic wave shielding film has, sequentially from the substrate side, a first high refractive index layer made of a material having a refractive index of at least 2.0, a first oxide layer containing zinc oxide as the main component, an electroconductive layer containing silver as the main component, and a second high refractive index layer made of a material having a refractive index of at least 2.0.
    Type: Application
    Filed: September 2, 2008
    Publication date: January 1, 2009
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Tohru YANAGISAWA, Tamotsu Morimoto
  • Patent number: 7394326
    Abstract: A method for manufacturing a quartz oscillator having a stable temperature drift characteristic attributed to the quartz oscillating piece and a quartz oscillator are disclosed. The method comprises a quartz crystal etching step S1 of processing a quartz oscillating piece into a predetermined shape by etching, an electrode membrane forming step S2 of forming an electrode on the quartz oscillating piece, a quartz crystal mounting step S3 of mounting the quartz oscillating piece in an oscillator package, a leakage oscillation adjusting step S4 of driving the mounted quartz oscillating piece, detecting the leakage oscillation, and removing a part of the quartz oscillating piece depending on the detected leakage oscillation, and a re-etching step S6 of re-etching the quartz oscillating piece subjected to the removal.
    Type: Grant
    Filed: March 28, 2005
    Date of Patent: July 1, 2008
    Assignee: Citizen Holdings Co., Ltd.
    Inventors: Maki Takizawa, Tohru Yanagisawa
  • Publication number: 20080057264
    Abstract: To provide an electromagnetic wave shielding laminate having a high visible light transmittance and having a low resistance and a high moisture resistance available at a low cost, and a display device using it. An electromagnetic wave shielding laminate 1 comprising a transparent substrate 2 and an electromagnetic wave shielding film 100 formed on the substrate, wherein the electromagnetic wave shielding film 100 has, sequentially from the substrate 2 side, a first high refractive index layer 31 made of a metal oxide having a refractive index of at least 2.0, a first oxide layer 32 containing zinc oxide and titanium oxide as the main components, an electroconductive layer 33 containing silver as the main component and a second high refractive index layer 35 made of a metal oxide having a refractive index of at least 2.0.
    Type: Application
    Filed: August 27, 2007
    Publication date: March 6, 2008
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Tamotsu Morimoto, Masato Kawasaki, Masahiro Fusen, Tohru Yanagisawa
  • Publication number: 20070176702
    Abstract: A method for manufacturing a quartz oscillator having a stable temperature drift characteristic attributed to the quartz oscillating piece and a quartz oscillator are disclosed. The method comprises a quartz crystal etching step S1 of processing a quartz oscillating piece into a predetermined shape by etching, an electrode membrane forming step S2 of forming an electrode on the quartz oscillating piece, a quartz crystal mounting step S3 of mounting the quartz oscillating piece in an oscillator package, a leakage oscillation adjusting step S4 of driving the mounted quartz oscillating piece, detecting the leakage oscillation, and removing a part of the quartz oscillating piece depending on the detected leakage oscillation, and a re-etching step S6 of re-etching the quartz oscillating piece subjected to the removal.
    Type: Application
    Filed: March 28, 2005
    Publication date: August 2, 2007
    Applicant: CITIZEN WATCH CO., LTD.
    Inventors: Maki Takizawa, Tohru Yanagisawa
  • Patent number: 7138288
    Abstract: A crystal resonator area and side electrode shielding/formation blocks thereabout are formed on a crystal substrate through etching with both areas kept separate from each other with a gap. Vapor deposition is diagonally applied through this gap toward the side of the crystal substrate to thereby form an electrode film divided into two portions in the thickness direction of the substrate on the side.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: November 21, 2006
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Akihiro Shioji, Tohru Yanagisawa
  • Publication number: 20050095449
    Abstract: An electromagnetic wave shielding laminate comprising a transparent substrate and an electromagnetic wave shielding film formed thereon, characterized in that the electromagnetic wave shielding film has, sequentially from the substrate side, a first high refractive index layer made of a material having a refractive index of at least 2.0, a first oxide layer containing zinc oxide as the main component, an electroconductive layer containing silver as the main component, and a second high refractive index layer made of a material having a refractive index of at least 2.0.
    Type: Application
    Filed: August 23, 2004
    Publication date: May 5, 2005
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Tohru Yanagisawa, Tamotsu Morimoto
  • Publication number: 20040191944
    Abstract: A crystal resonator area and side electrode shielding/formation blocks thereabout are formed on a crystal substrate through etching with both areas kept separate from each other with a gap. Vapor deposition is diagonally applied through this gap toward the side of the crystal substrate to thereby form an electrode film divided into two portions in the thickness direction of the substrate on the side.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 30, 2004
    Inventors: Akihiro Shioji, Tohru Yanagisawa
  • Patent number: 6675651
    Abstract: A vibration gyro has a vibrator composed of three tines (first, second, and third tines) which are aligned in a single line at prescribed intervals in one direction on a base and extend in a direction perpendicular to an aligning direction. A central second tine and an adjacent first tine on a left are driven by oscillator. Further, Coriolis force generated on the second tine and the third tine on a right is detected by a detector. In this vibration gyro, the dimensions of the parts are determined so as to cause the third tine to substantially stand still when the first and second tines are driven by the oscillator.
    Type: Grant
    Filed: September 6, 2002
    Date of Patent: January 13, 2004
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Tohru Yanagisawa, Izumi Yamamoto
  • Publication number: 20030056590
    Abstract: A vibration gyro has a vibrator composed of three tines (first, second, and third tines) which are aligned in a single line at prescribed intervals in one direction on a base and extend in a direction perpendicular to an aligning direction. A central second tine and an adjacent first tine on a left are driven by oscillator. Further, Coriolis force generated on the second tine and the third tine on a right is detected by a detector. In this vibration gyro, the dimensions of the parts are determined so as to cause the third tine to substantially stand still when the first and second tines are driven by the oscillator.
    Type: Application
    Filed: September 6, 2002
    Publication date: March 27, 2003
    Inventors: Tohru Yanagisawa, Izumi Yamamoto
  • Patent number: 6437490
    Abstract: The present invention provides a vibration gyro having good detection sensitivity and good detection accuracy and which comprises four beams provided on a base portion and which are made substantially stationary, for any type of vibration used. Since the vibration stimulus and detection make use of the same vibration mode, and the beams is so configured that output signals output from the beams cancel noise output generated by externally applied vibration, it is possible that matching of the excitation to obtain a large output signal and the resonant frequency for detection can be achieved without placing great expectations on machining and assembly precision, and without affecting adversely to the performance thereof depending upon a supporting method.
    Type: Grant
    Filed: March 22, 2000
    Date of Patent: August 20, 2002
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Tohru Yanagisawa, Izumi Yamamoto, Naoki Fujii
  • Patent number: 6281619
    Abstract: A four-beam tuning fork is provided in which the base part thereof is stationary regardless of the vibration of the resonator, the same vibration mode being used for both excitation and detection, and the outputs from a plurality of beams are used to cancel the noise output caused by externally applied vibration
    Type: Grant
    Filed: May 8, 1998
    Date of Patent: August 28, 2001
    Assignee: Citizen Watch Co., Ltd.
    Inventors: Tohru Yanagisawa, Izumi Yamamoto