Patents by Inventor Morito Akiyama

Morito Akiyama 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: 6823739
    Abstract: A thin pressure sensor includes: a pair of external electrodes, which are respectively made of conductive thin films that are respectively provided with piezoelectric layers on inner sides; and a single internal electrode, made of a conductive thin film, which is sealed between the pair of external electrodes, one of the pair of external electrodes having a conducting window that conducts to said internal electrode. The thin pressure sensor has a simple and thin structure with sufficient durability and mechanical strength.
    Type: Grant
    Filed: December 12, 2002
    Date of Patent: November 30, 2004
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Naohiro Ueno, Morito Akiyama, Kiichi Ikeda, Hiroshi Tateyama
  • Publication number: 20040135144
    Abstract: A thin film bulk acoustic resonator comprises a substrate (12) of a silicon single crystal, a base film (13) formed on the substrate (12) and composed of a dielectric film mainly containing silicon oxide, and a piezoelectric stacked structure (14) formed on the base film (13). A vibratory section (21) composed of a part of the base film (13) and a part of the piezoelectric stacked structure (14). The piezoelectric stacked structure (14) includes a lower electrode (15), a piezoelectric film (16), and an upper electrode (17) formed in this order from below. The substrate (12) had a via hole (20) in the region corresponding to the vibratory section (21). The via hole forms a space for allowing vibration of the vibratory section (21). The piezoelectric film (16) is an aluminum nitride thin film containing 0.2 to 3.0 atom % of alkaline earth metal and/or a rare earth metal.
    Type: Application
    Filed: November 10, 2003
    Publication date: July 15, 2004
    Inventors: Tetsuo Yamada, Keigo Nagao, Chisen Hashimoto, Morito Akiyama, Naohiro Ueno, Hiroshi Tateyama
  • Patent number: 6628375
    Abstract: This invention is to provide a method and a system which, by making use of a stress luminescent material, renders it possible to directly observe a stress distribution on the base of a real time without electrical contacts, and to easily measure a stress or a stress distribution and a stress image. Essentially, the invention comprises the steps of adding a stress to a tested body containing a stress luminescent material whose light emission is proportional to the stress, making visually observable a stress distribution over the tested body in accordance with a luminous intensity of the stress luminescent material contained in the tested body, measuring the luminous intensity of the luminescent material of the tested body, comparing the measured value of the luminous intensity with certain correlation data indicating a relationship between the luminous intensity of the stress luminescent material and a stress, thereby obtaining a stress value or a stress distribution over the tested body.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: September 30, 2003
    Assignee: Agency of Industrial Science and Technology
    Inventors: Chao-Nan Xu, Morito Akiyama, Kazuhiro Nonaka, Tadahiko Watanabe
  • Patent number: 6606911
    Abstract: A pressure sensor is formed by sandwiching a pressure-sensitive dielectric membrane between and in contact with a pair of electrodes. As pressure is applied, the dielectric constant of the pressure-sensitive membrane changes while the distance of separation between the pair of electrodes remains constant. This change in the dielectric constant is detected by a circuit as a change in the electrostatic capacitance between the electrodes to measure the applied pressure. Since the pressure-sensitive dielectric membrane is not required to undergo any elastic deformation for measuring the pressure, the pressure sensor can be made extremely thin.
    Type: Grant
    Filed: December 5, 2001
    Date of Patent: August 19, 2003
    Assignee: Omron Corporation
    Inventors: Morito Akiyama, Masahiro Kinoshita, Hideyuki Bingo, Makoto Nakamura
  • Patent number: 6608427
    Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.
    Type: Grant
    Filed: September 9, 2002
    Date of Patent: August 19, 2003
    Assignee: Agency of Industrial Science and Technology
    Inventors: Morito Akiyama, Naohiro Ueno, Kiichi Ikeda, Kazuhiro Nonaka, Hiroshi Tateyama
  • Publication number: 20030124383
    Abstract: A mechanoluminescence material of the present invention is produced by adding a luminescence center to a mother body material, wherein: said mother body material is constituted of at least one kind of oxide selected from alumino silicate, aluminate, silicate, tantalate, niobate, gallium oxide, and ZrO2, and said luminescence center is at least one kind selected from a rare earth metal and a transition metal which emits light when electrons excited by mechanical energy are restored to a normal state.
    Type: Application
    Filed: November 22, 2002
    Publication date: July 3, 2003
    Inventors: Morito Akiyama, Chao-Nan Xu, Kazuhiro Nonaka
  • Publication number: 20030115966
    Abstract: A thin pressure sensor includes: a pair of external electrodes, which are respectively made of conductive thin films that are respectively provided with piezoelectric layers on inner sides; and a single internal electrode, made of a conductive thin film, which is sealed between the pair of external electrodes, one of the pair of external electrodes having a conducting window that conducts to said internal electrode. The thin pressure sensor has a simple and thin structure with sufficient durability and mechanical strength.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 26, 2003
    Inventors: Naohiro Ueno, Morito Akiyama, Kiichi Ikeda, Hiroshi Tateyama
  • Patent number: 6555886
    Abstract: Disclosed is an electronic device having a multilayered structure consisting of (a) a substrate, (b) an electroconductive layer of lanthanum nickel oxide LaNiO3 having a perovskite structure formed on the substrate surface and (c) a dielectric layer of PZT having an oriented perovskite structure formed on the electroconductive layer. The device exhibits excellent piezoelectric effect under mechanical stress and stable hysteresis phenomenon of electric polarization under application of electric fields so that the device is useful as a stress sensor and as a memory device. A method for the preparation of the multilayered device is disclosed.
    Type: Grant
    Filed: January 24, 2002
    Date of Patent: April 29, 2003
    Assignee: Agency of Industrial Science and Technology
    Inventors: Chaonan Xu, Tadahiko Watanabe, Yun Liu, Morito Akiyama
  • Patent number: 6536476
    Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.
    Type: Grant
    Filed: January 16, 2002
    Date of Patent: March 25, 2003
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Naohiro Ueno, Morito Akiyama, Hiroyuki Nakamura
  • Publication number: 20030006678
    Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.
    Type: Application
    Filed: September 9, 2002
    Publication date: January 9, 2003
    Inventors: Morito Akiyama, Naohiro Ueno, Kiichi Ikeda, Kazuhiro Nonaka, Hiroshi Tateyama
  • Publication number: 20020096222
    Abstract: The invention discloses a method for fine control of the flow rate of a liquid by a microvalve device without using any mechanical structures. The method comprises, while passing the liquid through a flow channel penetrating a substrate of a heat-insulating material, the temperature of the liquid in the flow channel is decreased below the freezing point of the liquid by a temperature-controlling means such as a Peltier element facing the flow channel to close the flow channel by the solidified liquid and the temperature of the solidified liquid is increased above the melting point thereof to cause thawing of the solid resulting in re-opening of the flow channel.
    Type: Application
    Filed: January 16, 2002
    Publication date: July 25, 2002
    Inventors: Naohiro Ueno, Morito Akiyama, Hiroyuki Nakamura
  • Publication number: 20020078756
    Abstract: A pressure sensor is formed by sandwiching a pressure-sensitive dielectric membrane between and in contact with a pair of electrodes. As pressure is applied, the dielectric constant of the pressure-sensitive membrane changes while the distance of separation between the pair of electrodes remains constant. This change in the dielectric constant is detected by a circuit as a change in the electrostatic capacitance between the electrodes to measure the applied pressure. Since the pressure-sensitive dielectric membrane is not required to undergo any elastic deformation for measuring the pressure, the pressure sensor can be made extremely thin.
    Type: Application
    Filed: December 5, 2001
    Publication date: June 27, 2002
    Inventors: Morito Akiyama, Masahiro Kinoshita, Hideyuki Bingo, Makoto Nakamura
  • Publication number: 20020017835
    Abstract: Disclosed is a high-sensitivity flexible ceramic sensor for detecting mechanical shocks and vibrations, which comprises a metal foil of a specified thickness as a substrate, a single-crystalline thin film of a piezoelectric ceramic material such as aluminum nitride and zinc oxide having a specified thickness formed on the substrate, a metallic electrode formed on the thin ceramic film and an external circuit connecting the metal foil and the electrode with insertion of an electric meter for measuring the piezoelectric voltage changes induced in the ceramic thin film.
    Type: Application
    Filed: December 12, 2000
    Publication date: February 14, 2002
    Inventors: Morito Akiyama, Naohiro Ueno, Kiichi Ikeda, Kazuhiro Nonaka, Hiroshi Tateyama
  • Publication number: 20010017059
    Abstract: This invention is to provide a method and a system which, by making use of a stress luminescent material, renders it possible to directly observe a stress distribution on the base of a real time without electrical contacts, and to easily measure a stress or a stress distribution and a stress image. Essentially, the invention comprises the steps of adding a stress to a tested body containing a stress luminescent material whose light emission is proportional to the stress, making visually observable a stress distribution over the tested body in accordance with a luminous intensity of the stress luminescent material contained in the tested body, measuring the luminous intensity of the luminescent material of the tested body, comparing the measured value of the luminous intensity with certain correlation data indicating a relationship between the luminous intensity of the stress luminescent material and a stress, thereby obtaining a stress value or a stress distribution over the tested body.
    Type: Application
    Filed: December 29, 2000
    Publication date: August 30, 2001
    Applicant: Agency of Industrial Science and Technology
    Inventors: Chao-Nan Xu, Morito Akiyama, Kazuhiro Nonaka, Tadahiko Watanabe
  • Patent number: 6280655
    Abstract: Disclosed is a high-efficiency stress-luminescent material capable of emitting luminescence by receiving a mechanical stress such as compression, shearing and rubbing. The stress-luminescent material is an alkaline earth aluminate of a non-stoichiometric composition deficient in the content of the alkaline earth element by 0.01 to 20% by moles from stoichiometry. The efficiency of stress-luminescence emission can be further enhanced when the non-stoichiometric alkaline earth aluminate contains 0.01 to 10% by moles of rare earth metal ions or transition metal ions. The stress-luminescent material is prepared by subjecting a non-stoichiometric composite oxide of aluminum oxide and an alkaline earth oxide to a calcination treatment at 800 to 1700° C. in a reducing atmosphere.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: August 28, 2001
    Assignee: Japan as represented by Secretary of Agency of Industrial Science and Technology
    Inventors: Chaonan Xu, Tadahiko Watanabe, Morito Akiyama, Kazuhiro Nonaka
  • Patent number: 6240786
    Abstract: A two-layer structure composite material, by which it is possible to easily detect the occurrence of the cracks occurred in the structural material and to predict the possible destruction of the structural material before it actually occurs. To a structural material, a voltage generating material consisting of a ferroelectric material, a pyroelectric material or a piezoelectric material, is bonded to produce a two-layer structure material, and an electrode is provided for detecting voltage, which is generated owing to impact force.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: June 5, 2001
    Assignee: Agency of Industrial Science and Technology
    Inventors: Morito Akiyama, Tadahiko Watanabe, Kazuhiro Nonaka
  • Patent number: 6159394
    Abstract: The present invention provides a new stress emission material that is different from the other known materials and that efficiently emits light when subjected to a mechanical external force such as a frictional force, a shear force, an impact, or a pressure. This stress emission material is configured by adding an emission center comprising one or more rare earths or transition metals that emit light when electrons excited by a mechanical force return to their normal state, to a base material comprising one or more of an oxide, a sulfide, a carbide, and a nitride each having an FeS.sub.2 structure. This material has an emission intensity that depends on stress.
    Type: Grant
    Filed: February 5, 1999
    Date of Patent: December 12, 2000
    Assignee: Agency of Industrial Science and Technology
    Inventors: Morito Akiyama, Chaonan Xu, Kazuhiro Nonaka, Tadahiko Watanabe
  • Patent number: 6117574
    Abstract: Provided by the invention is a novel synthetic inorganic triboluminescent material in the form of a powder, sintered block or thin film, of which the matrix phase is a piezoelectric crystalline material of a wurtzite structure such as zinc sulfide and the activator to serve as the center of luminescence is a transition metal element such as manganese, copper and rare earth elements in an amount of 0.01 to 10% by weight. The triboluminescent material is prepared by subjecting a powder blend of the matrix phase material and a thermally decomposable compound of the activator element first to a preparatory calcination treatment at 500 to 800.degree. C. and then, preferably in the form of a powder compact, to a second calcination treatment at 900 to 1700.degree. C., preferably, in vacuum under a sealed condition, when the material is liable to cause sublimation, or in an atmosphere of a reducing gas.
    Type: Grant
    Filed: October 15, 1998
    Date of Patent: September 12, 2000
    Assignee: Agency of Industrial Science and Technology
    Inventors: Tadahiko Watanabe, Chaonan Xu, Morito Akiyama
  • Patent number: 5585313
    Abstract: The present invention provides a SiC-MoSi.sub.2 infiltration material with high heat-resistant property, which can be used at 1500.degree. C. under atmospheric condition, can be produced at lower manufacturing temperature, and can maintain high resistance to oxidation. This ceramic composite material with high heat-resistant property can be obtained by infiltrating aluminum silicide of molybdenum, which is expressed by a formula of Mo(Al.sub.x Si.sub.1-x).sub.2 (where 0.1<x<0.5) into a porous preform of silicon carbide having porosity of 10 to 50% in volume ratio.
    Type: Grant
    Filed: August 31, 1994
    Date of Patent: December 17, 1996
    Assignee: Agency of Industrial Science and Technology
    Inventors: Kazuhisa Shobu, Tadahiko Watanabe, Eiji Tani, Morito Akiyama