Patents by Inventor Wasaburo Ohta

Wasaburo Ohta 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: 5465475
    Abstract: A thin film magnetic head has a lower magnetic pole formed on a substrate; a coil arranged on the lower magnetic pole through an adhesive layer; an upper magnetic pole arranged on the coil; and a gap layer formed between the upper and lower magnetic poles. A method for forming the thin film magnetic head has a process for forming a lower magnetic pole on a first substrate; a process for forming a coil on a second substrate having a recessed portion; a process for polishing the first and/or second substrate such that a face of the lower magnetic pole on the first substrate and a face of the coil on the second substrate come in close contact with each other; a process for adhering the first and second substrates to each other such that the lower magnetic pole and the coil are adjacent to each other; a process for forming a gap layer on the lower magnetic pole; a process for polishing or etching a portion or all of the second substrate; and a process for forming an upper magnetic pole.
    Type: Grant
    Filed: July 29, 1993
    Date of Patent: November 14, 1995
    Assignee: Ricoh Co., Ltd.
    Inventors: Mikio Kinoshita, Wasaburo Ohta
  • Patent number: 5427668
    Abstract: A thin film deposition system includes a vacuum or evacuated casing in which there is introduced an active gas or an inert gas or a mixture thereof. A filament emits thermions which impinge upon gas molecules to ionize them into positive ions. The ions bombard a target, from which particles are emitted toward a substrate. The particles emitted from the target are also ionized by the thermions. In the vicinity of a grid, more particles from the target are ionized by thermions which are vertically oscillated and ionized molecules of the gas. The ions are accelerated toward the substrate and bombard the substrate, thereby depositing a thin film thereon. The thin film deposition system may additionally have an evaporation source for supporting an evaporant which emit particles to be deposited on the substrate.
    Type: Grant
    Filed: October 22, 1990
    Date of Patent: June 27, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Tatsuya Sato, Wasaburo Ohta, Mikio Kinoshita
  • Patent number: 5368908
    Abstract: An optical information recording medium, for writing in and reading out information by a laser beam, is composed of a recording layer, an anti-reflection layer structure formed on an outer surface section on which the laser beam is directed to be focused, on the recording layer, and the anti-reflection layer structure includes one or more transparent electroconductive film layers.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: November 29, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Isamu Orima, Masashi Nakazawa, Yuzi Onodera, Kazuhiro Umeki
  • Patent number: 5251202
    Abstract: An optical information recording medium is composed of a transparent substrate, a recording layer provided on the substrate, which is transparent with respect to a light beam for reproducing information recorded in the recording layer, a reflection layer provided on the recording layer, and an anti-reflection layer provided on the back side of the substrate opposite to the recording layer. The anti-reflection layer is composed of a plurality of overlaid layers, and at least one of the layers being a transparent electroconductive layer and the other layers are transparent insulating layers.
    Type: Grant
    Filed: May 14, 1992
    Date of Patent: October 5, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Yujiro Kaneko, Wasaburo Ohta, Masashi Nakazawa, Michiaki Shinozuka, Isao Miyamoto, Hitoshi Nakamura, Toshihiko Yoshio, Masaaki Ishiyama, Yuuzi Onodera
  • Patent number: 5250170
    Abstract: A gas sensor includes a substrate, a heater member formed on the base member, a gas sensitive structure formed on the heater member by a process comprising the following steps of forming a stacked layer structure on the heater member, the stacked layer structure including at least a metal-oxide semiconductor layer and an insulating film, and carrying out a heat treatment with respect to the stacked layer structure so that a constituent of the insulating film is diffused in spaces among crystal particles of the metal-oxide semiconductor layer, and electrode layers are in contact with the gas sensitive structure.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: October 5, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta
  • Patent number: 5147523
    Abstract: A gas sensor senses gas using a metal oxide semiconductor whose resistance changes depending on gas adhesion on a surface of the metal oxide semiconductor. The gas sensor includes a base structure, and a gas sensitive layer formed on the base structure and made of a metal oxide semiconductor. The gas sensitive layer has a multi-layer structure which includes at least two layer portions having mutually different grain structures.
    Type: Grant
    Filed: June 10, 1991
    Date of Patent: September 15, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta
  • Patent number: 5133849
    Abstract: An apparatus for forming a thin film has a vacuum container to which an active gas, an inert gas or a mixture thereof is introduced, and a source of evaporation from which a substance is evaporated. A counter electrode is disposed in the vacuum container for holding a substrate for forming a thin film thereon in such a manner as to be opposed to the source of evaporation. A grid is disposed between the source of evaporation and the counter electrode and having openings which allow the evaporated substance to pass therethrough. A filament for thermionic emission is disposed between the grid and the source of evaporation. A target is also disposed between the filament and the source of evaporation for emitting sputtered particles. A power source device establishes predetermined electric potential relationships between the grid, the filament, and the target.
    Type: Grant
    Filed: December 11, 1989
    Date of Patent: July 28, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Mikio Kinoshita, Wasaburo Ohta, Tatsuya Sato, Masashi Nakazawa
  • Patent number: 5114559
    Abstract: A thin film deposition system includes an evacuated casing in which there is introduced an active gas or an inert gas or a mixture thereof. An evaporant carried by an evaporation source in the evacuated casing is evaporated and travels toward a substrate supported on the electrode. A filament for emitting thermions is disposed between the evaporation source and the electrode, and a grid for passing the evaporated material therethrough is disposed between the filament and the electrode. Power supplies are electrically connected to the evacuated casing, the evaporation source, the electrode, the filament, and the grid, for keeping the filament negative in potential with respect to the evacuated casing and the grid. Alternatively, the evacuated casing may not be connected to the power supplies so that the grid is kept positive with respect to the filament. The grid may be of a double-layer structure, with the gas inlet means connected to the grid.
    Type: Grant
    Filed: September 25, 1990
    Date of Patent: May 19, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Masashi Nakazawa, Mikio Kinoshita
  • Patent number: 5112466
    Abstract: An apparatus for forming a thin film having a vacuum container evacuated to high vacuum and receiving a gas for vapor deposition, a generation device for generating a material vapor, a counter electrode holding a substrate to be vapor-deposited, a first grid disposed between the generation device and the electrode for accelerating the vapor, and a filament for emitting thermions to ionize the vapor. The grid and counter electrode surfaces may be curved and parallel to each other, and a second grid for accelerating the vapor, having a potential which is negative with respect to the potential of the first grid, may be placed between the first grid and the electrode, in the vicinity of the electrode, and a device may be provided for moving the first grid with respect to the electrode on a predetermined track.
    Type: Grant
    Filed: September 14, 1990
    Date of Patent: May 12, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Mikio Kinoshita, Tadao Katsuragawa
  • Patent number: 5058527
    Abstract: A thin film forming apparatus for forming a thin film on a substrate with a vaporized source material being supplied from an external material supplying unit.
    Type: Grant
    Filed: July 24, 1990
    Date of Patent: October 22, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Masashi Nakazawa
  • Patent number: 5019885
    Abstract: A gas detecting device includes a substrate and a plurality of gas sensitive elements supported by the substrate. A plurality of predetermined temperatures at which gases are detected are provided. The gas detecting device also includes a plurality of pairs of electrode leads supported by the substrate, each of the plurality of pairs of electrodes being connected to a corresponding one of the gas sensitive elements, and heater leads that are supported by the substrate and heat the plurality of gas sensitive elements so that each of the gas sensitive elements is set at a corresponding one of the plurality of predetermined temperatures.
    Type: Grant
    Filed: March 28, 1990
    Date of Patent: May 28, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta
  • Patent number: 5012671
    Abstract: A gas detecting device includes a substrate and a plurality of overhang portions made from an electric insulation material and disposed in a space over the substrate. A gas sensitive film is made from a metallic oxide semiconductor material and is mounted on each of the overhang portions. A pair of detecting leads is connected to the gas sensitive film. A heater lead for heating the gas sensitive film is mounted on each of the overhang portions. The gas sensitive film of at least one of the plurality of overhang portions has a composition ratio of metal to oxygen different from that of the other gas sensitive films whereby a specified gas can be selectively detected on the basis of the response of the plurality of metallic oxide semiconductors to the gas.
    Type: Grant
    Filed: November 13, 1989
    Date of Patent: May 7, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta
  • Patent number: 5003812
    Abstract: A gas detecting device includes a substrate, an insulator layer formed on the substrate, a gas sensitive layer formed the insulator layer, a pair of detection leads formed on the insulator layer, the gas sensitive layer partially overlying the pair of detection leads, a signal derived from the gas sensitive layer being sent to an external circuit through the pair of detection leads, a heater member arranged on the insulator layer in the vicinity of the gas sensitive layer, and an insulation coating layer formed on the pair of detection leads and the heater member, and partially overlying the gas sensitive layer so that the gas sensitive layer is put between the insulator layer and the insulation coating layer, and a portion of an upper surface of the gas sensitive layer is exposed to gas.
    Type: Grant
    Filed: July 30, 1990
    Date of Patent: April 2, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Junji Manaka, Wasaburo Ohta
  • Patent number: 4984446
    Abstract: A gas detecting device includes a substrate, an insulating layer supported by the substrate, first and second pairs of detection leads formed on the insulating layer, a heater lead formed on the insulating layer, the first and second pairs of detection leads being heated by passing a heater driving current through the heater lead, a gas sensitive layer formed of a gas sensitive material and provided so as to partially make contact with the first and second pairs of detection leads, and a passivation layer formed so as to cover the first and second pairs of detection leads and the heater lead. A gas detection signal is output from the gas sensitive layer through one of the first and second pairs of detection leads. A gas detecting system including the above gas detecting device is also provided.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: January 15, 1991
    Assignees: Ricoh Company, Ltd., Ricoh Seiki Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta, Junji Manaka
  • Patent number: 4982696
    Abstract: An apparatus for forming thin film includes a vacuum container to which an active gas, an inert gas, or a mixture thereof is introduced, a source of evaporation for evaporating a substance being evaporated in the vacuum container, a counter electrode disposed in the vacuum container and holding a substrate for forming a thin film thereon in such a manner as to be opposed to the source of evaporation, a grid disposed between the source of evaporation and the counter electrode and having openings which allow the substance being evaporated to pass therethrough, a filament for thermionic emission disposed between the grid and the source of evaporation and a power source device for establishing a predetermined electric potential relationship between the grid, the counter electrode, and the filament.
    Type: Grant
    Filed: January 6, 1989
    Date of Patent: January 8, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Mikio Kinoshita, Wasaburo Ohta, Masashi Nakazawa
  • Patent number: 4974544
    Abstract: A vapor deposition apparatus includes a vacuum chamber into which an active gas, an inert gas or a mixture of the active gas and the inert gas, a reactor for converting a gaseous raw material into a gaseous thin-film forming substance, and a nozzle attached to the reactor so as to blow out the gaseous thin-film forming substance toward a substrate supported by a counter electrode. The nozzle is so adapted as to bring about a pressure difference between an interior space of the reactor and the vacuum chamber, which pressure difference causes the blown-out gaseous thin-film forming substance to be formed a cluster. The vapor deposition apparatus makes it possible to deposit a thin-film on a substrate having poor thermal stability and to form highly dense thin-film.
    Type: Grant
    Filed: February 2, 1990
    Date of Patent: December 4, 1990
    Assignee: Ricoh Company, Co.
    Inventor: Wasaburo Ohta
  • Patent number: 4967589
    Abstract: A gas detecting device includes a substrate, an insulator layer formed on the substrate, a gas sensitive layer formed the insulator layer, a pair of detection leads formed on the insulator layer, the gas sensitive layer partially overlying the pair of detection leads, a signal derived from the gas sensitive layer being sent to an external circuit through the pair of detection leads, a heater member arranged on the insulator layer in the vicinity of the gas sensitive layer, and an insulation coating layer formed on the pair of detection leads and the heater member, and partially overlying the gas sensitive layer so that the gas sensitive layer is put between the insulator layer and the insulation coating layer, and a portion of an upper surface of the gas sensitive layer is exposed to gas.
    Type: Grant
    Filed: December 22, 1988
    Date of Patent: November 6, 1990
    Assignees: Ricoh Company, Ltd., Ricoh Seiki Company, Ltd.
    Inventors: Shinji Yagawara, Junji Manaka, Wasaburo Ohta
  • Patent number: 4966095
    Abstract: An apparatus for forming a thin film comprises a vacuum container evacuated to high vacuum and receiving a gas for vapor deposition, a source of evaporation in the container for evaporating a substance, a counter electrode in the container holding a substrate to be vapor-deposited such that the substrate opposes the source, a filament disposed between the source and the electrode for generating thermions, and a grid disposed between the filament and the electrode for allowing the evaporated substance to pass therethrough and accelerating the evaporated substance. An electrical potential power supply is connected to the electrode, the filament and the grid for maintaining the grid at a positive potential with respect to the electrode and the filament, and an electrical heating power supply is connected to the grid for supplying the grid with an electrical power so as to electrically heat the grid.
    Type: Grant
    Filed: August 10, 1989
    Date of Patent: October 30, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Masashi Nakazawa
  • Patent number: 4960072
    Abstract: An apparatus for forming a thin film having a vacuum container evacuated to high vacuum and receiving a gas for vapor deposition, a generation device for generating a material vapor, a counter electrode holding a substrate to be vapor-deposited, a first grid disposed between the generation device and the electrode for accelerating the vapor, and a filament for emitting thermions to ionize the vapor. The first grid and counter electrode surfaces may be curved and parallel to each other, and a second grid for accelerating the vapor, having a potential which is negative with respect to the potential of the first grid, may be placed between the first grid and the electrode, in the vicinity of the electrode, and a device may be provided for moving the first grid with respect to the electrode on a predetermined track.
    Type: Grant
    Filed: August 5, 1988
    Date of Patent: October 2, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Mikio Kinoshita, Tadao Katsuragawa
  • Patent number: 4947688
    Abstract: A flow velocity sensor comprises a base, a first elongating member extending above the base and defined with a first edge at a downstream end thereof, a first heating device provided on the first elongating member along the first edge, a first heat detector provided on the first elongating member in a vicinity of the first heating device at a side away from the first edge and comprising a first metal oxide which absorbs oxygen when heated, desorbs oxygen when cooled, and changes resistivity responsive to adsorption and desorption of oxygen, a second elongating member extending above the base at a downstream side of the first elongating member and having a second edge at an upstream end thereof such that the second edge is substantially aligned with the first edge in a flow direction, a second heating device provided on the second elongating member along the second edge, and a second heat detector provided on the second elongating member in a vicinity of the second heating device at a side away from the second
    Type: Grant
    Filed: August 15, 1989
    Date of Patent: August 14, 1990
    Assignee: Ricoh Company, Ltd.
    Inventors: Shinji Yagawara, Wasaburo Ohta