Patents by Inventor Akira Kawai

Akira Kawai 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: 5263008
    Abstract: A magneto-optical disk device, in which data are written and read in and from a magneto-optical disk housed in a magneto-optical disk cartridge having a head window of a predetermined shape, comprises: first and second magneto-optical heads disposed so as to locate in the head window for accessing the magneto-optical disk; a center rail disposed substantially at the center of the window head along a diameter of the magneto-optical disk; a first side rail and a second side rail which are disposed parallelly with each other on both sides of the center rail; a first carriage slidably disposed between the center rail and the first side rail, and having at least a part of the first magneto-optical head mounted thereon; first driving means for driving the first carriage along the center rail; a second carriage slidably disposed between the center rail and the second side rail, and having at least a part of the second magneto-optical head mounted thereon; and second driving means for driving the second carriage alon
    Type: Grant
    Filed: August 30, 1991
    Date of Patent: November 16, 1993
    Assignee: Tosoh Corporation
    Inventors: Kazuyuki Fujio, Akira Kawai, Shuzo Mizutani, Katsuaki Ishimaru
  • Patent number: 5195072
    Abstract: An error detecting device for an optical head detects a focussing error and a tracking error. The error detection device includes an optical structure for converting a reflected light of a light irradiating a surface to be irradiated into an astigmatic pencil of rays having a first focal point and a second focal point, the optical structure having a first focussing member for focussing the reflected light on the first focal point of the astigmatic pencil of rays, and a second focussing member for focussing the reflected light on the second focal point of the astigmatic pencil of rays, the first and the second focussing members being made integral, and a device for detecting errors of the light irradiating the surface to be irradiated, based on a detecting signal of a spot of the reflected light formed by the first focussing member, and a detecting signal of a spot of said reflected light formed by the second focussing member.
    Type: Grant
    Filed: March 23, 1989
    Date of Patent: March 16, 1993
    Assignee: Tosoh Corporation
    Inventors: Kenji Fukui, Akira Kawai
  • Patent number: 5080586
    Abstract: There is disclosed a device for detecting the position of an apical foramen of a tooth's root by measuring a change in the impedance between a measuring needle inserted into a tooth's root canal and an electrode abutting on oral mucosa. This device includes a circuit for generating two kinds of different frequency signals, detection circuits for detecting a change in the impedance in response to the respective frequencies and a "difference" detection circuit for successively comparing outputs of the detection circuits and for producing a "difference" signal, and a feed back circuit for feeding an output of the "difference" detection circuit to one of the input terminals of the "difference" detection circuit so as to equalize its two inputs by addition or by subtraction and thereby to make its output equal to zero.
    Type: Grant
    Filed: September 24, 1990
    Date of Patent: January 14, 1992
    Assignee: Osada Research Institute, Ltd.
    Inventor: Akira Kawai
  • Patent number: 5068067
    Abstract: Disclosed in this invention are an emulsifier for producing microcapsules, containing as active principle a water-soluble polymer the emulsifier being composed of benzyl (meth)acrylate and/or diisobutylene, styrene and maleic anhydride, microcapsules using the emulsifier, a process for producing the microcapsules, and a non-carbon pressure-sensitive copying paper using the microcapsules.
    Type: Grant
    Filed: October 18, 1989
    Date of Patent: November 26, 1991
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Akira Kawai, Yoshihide Murakami
  • Patent number: 5001084
    Abstract: A method of applying a treatment liquid to a semiconductor wafer to form a coating include rotating a semiconductor wafer in its own plane within a hermetically-sealed container, discharging a cleaning fluid through a cleaning fluid nozzle onto the top surface of the wafer as it rotates, and then discharging a treatment liquid through a treatment liquid nozzle onto the center of the top surface of the wafer as it rotates. An apparatus for coating a treatment liquid on a semiconductor wafer comprises a hermetically-sealed container, a wafer chuck which rotates a semiconductor wafer in its own plane, a treatment liquid nozzle for connection to a supply of treatment liquid and discharging the treatment liquid onto the center of the top surface of the wafer as it rotates, and a cleaning fluid nozzle which is disposed to discharge a pressurized cleaning fluid onto the top surface of the wafer as it rotates.
    Type: Grant
    Filed: May 26, 1989
    Date of Patent: March 19, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Kawai, Shigeo Uoya
  • Patent number: 4956310
    Abstract: A semiconductor memory device in accordance with the present invention comprises: a semiconductor substrate (1) of a first conductivity type; a charge storage region (6) and a bit line region (7) of a second conductivity type formed on a main surface of the substrate; highly doped regions (12a, 12b) of the first conductivity type formed respectively contiguous to only the bottom boundaries of the charge storage region (6) and the bit line region (7).
    Type: Grant
    Filed: October 5, 1988
    Date of Patent: September 11, 1990
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Akira Tokui, Shinichi Sato, Akira Kawai, Masayuki Nakajima, Hiroji Ozaki, Masao Nagatomo
  • Patent number: 4931422
    Abstract: A no-carbon pressure-sensitive copying paper obtained by coating a composition containing an alkali thickening type copolymer latex as a binder on a support is excellent in color forming properties, resistance to smudge and high concentration coating suitability.
    Type: Grant
    Filed: August 17, 1988
    Date of Patent: June 5, 1990
    Assignee: Mitsubishi Paper Mills Limited
    Inventors: Mamoru Ishiguro, Akira Kawai
  • Patent number: 4763182
    Abstract: A semiconductor memory device comprises a first conductivity type semiconductor substrate (1) formed thereon with a charge storage region (5) and a second conductivity type region (6) serving as a bit line, and first conductivity type highly concentrated regions (8, 11) higher in concentration than the semiconductor substrate (1) at least by one digit are formed to enclose the charge storage region (5) and the bit line region (6) respectively. Thus, potential barriers against electrons can be defined in interfaces between the highly concentrated region (8) and the charge storage region (5) and between the highly concentrated region (11) and the bit line region (6), thereby to prevent malfunction caused by incidence of radioactive rays such as alpha rays.
    Type: Grant
    Filed: December 12, 1986
    Date of Patent: August 9, 1988
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroji Ozaki, Shinichi Sato, Akira Tokui, Akira Kawai, Masayuki Nakajima, Masao Nagatomo
  • Patent number: 4702796
    Abstract: The present invention is a method for fabricating a semiconductor device, wherein impurity is selectively diffused to surround a region (7) of a second conductivity type as a bit line formed on a semiconductor substrate (1), thereby forming an impurity diffused region (9) of a first conductivity type having high density and, by extending the impurity diffused region (9) in the element separating step to form a high density region of the first conductivity type having high density.
    Type: Grant
    Filed: November 14, 1986
    Date of Patent: October 27, 1987
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Masayuki Nakajima, Shinichi Sato, Akira Tokui, Akira Kawai, Masao Nagatomo, Hiroji Ozaki
  • Patent number: 4533599
    Abstract: By using, in production of microcapsules, a partially esterified product of a styrene-maleic anhydride copolymer as an emulsifier, advantages are obtained that coloring of emulsion can be reduced/prevented at the time of emulsification and, when the microcapsules produced are used in a carbonless copying paper, a desensitizer component is not transferred to a lower paper and accordingly color development is not hindered.
    Type: Grant
    Filed: March 23, 1984
    Date of Patent: August 6, 1985
    Assignee: Mitsubishi Paper Mills, Ltd.
    Inventors: Fumio Okumura, Akira Kawai