Patents by Inventor Satoshi Yamashita

Satoshi Yamashita 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: 7283445
    Abstract: A signal detection sections detect the light intensity modulated by the phase pits as ROM signals from the return lights of an optical storage medium that has phase pits and a recording layer to simultaneously regenerate data in the ROM and RAM, and detect the RAM signals where the return lights were modulated by the recording film. A feedback circuit reduces the cross-talk of the phase pits of the RAM signals of the recording film by feeding back the ROM signals to the laser drive current of the laser element, and a circuit for adjusting the feedback circuit so as to present a constant cross-talk suppression effect regardless the temperature change of the laser element. Since the feedback gain is changed by changing the laser temperature, an RF feedback gain, with which MO signals are not deteriorated by the change of the laser temperature, can be set.
    Type: Grant
    Filed: January 31, 2005
    Date of Patent: October 16, 2007
    Assignee: Fujitsu Limited
    Inventor: Satoshi Yamashita
  • Publication number: 20070230014
    Abstract: A heater for changing a projection distance protrusion value by thermal expansion accompanying electric-power-distributed heating is embedded in a head having a reading element and a recording element. A clearance control information measurement unit measures and saves, at desired correction timing, clearance control information including a clearance required for controlling the clearance between the reading element and the recording medium, heater projection sensitivity protrusion sensitivity, projection distance protrusion value transition time, recording current projection distance protrusion value, and a temperature correction coefficient. The clearance control unit varies the electric power distributed to the heater and changes the projection distance protrusion value of the head, thereby controlling the clearance to a target clearance upon reproduction and recording.
    Type: Application
    Filed: September 18, 2006
    Publication date: October 4, 2007
    Inventors: Satoshi Yamashita, Shunji Saitou, Yukio Abe, Shigenori Yanagi
  • Publication number: 20070230015
    Abstract: A heater for changing a projection distance protrusion value by thermal expansion accompanying electric-power-distributed heating is provided in a head having at least a reading element. At desired correction timing, a changed distance detection unit measures a clearance changed distance in a state in which the head is positioned to a track on the recording medium while increasing the amount of electric power distributed to the heater. A contact determination unit determines that the head is brought into contact with the recording medium when a derivative value of the clearance changed distance is below a predetermined threshold value. A measurement output unit outputs the clearance changed distance detected by the changed distance detection unit at the time of contact determination of the contact determination unit as a measurement result of the clearance between the reading element and the recording medium.
    Type: Application
    Filed: September 20, 2006
    Publication date: October 4, 2007
    Inventors: Satoshi Yamashita, Shunji Saitou, Yukio Abe, Shigenori Yanagi
  • Patent number: 7277253
    Abstract: A storage device configured to load and unload a head against a storage medium, includes a latch mechanism configured to latch the unloaded head, a head moving mechanism configured to move the head, a measuring part configured to measure an unlatch force necessary for unlatching the head latched by the latch mechanism, by applying a constant electrical current to the head mechanism so that the head is moved in a load direction, by measuring a back electromotive voltage, and calculating a moving speed and acceleration of the head, a storing part configured to store information indicating the measured unlatch force in the storage device, and a control part configured to apply a driving electrical current corresponding to the stored information to the head moving mechanism where the head is latched by the latch mechanism at the time of loading.
    Type: Grant
    Filed: February 21, 2006
    Date of Patent: October 2, 2007
    Assignee: Fujitsu Limited
    Inventors: Satoshi Yamashita, Takeshi Hara, Yoshifumi Obara
  • Publication number: 20070064331
    Abstract: A storage device configured to load and unload a head against a storage medium, includes a latch mechanism configured to latch the unloaded head, a head moving mechanism configured to move the head, a measuring part configured to measure an unlatch force necessary for unlatching the head latched by the latch mechanism, by applying a constant electrical current to the head mechanism so that the head is moved in a load direction, by measuring a back electromotive voltage, and calculating a moving speed and acceleration of the head, a storing part configured to store information indicating the measured unlatch force in the storage device, and a control part configured to apply a driving electrical current corresponding to the stored information to the head moving mechanism where the head is latched by the latch mechanism at the time of loading.
    Type: Application
    Filed: February 21, 2006
    Publication date: March 22, 2007
    Inventors: Satoshi Yamashita, Takeshi Hara, Yoshifumi Obara
  • Patent number: 7009219
    Abstract: A small, simple current-injection diamond ultraviolet light-emitting device comprising a high-quality diamond grown by chemical vapor deposition (CVD) method (1), a surface conductive layer (2) provided on the surface of the diamond, and electrodes (4, 5) provided on the surface conductive layer. The device is a free-exciton recombination emission diamond ultraviolet light-emitting device comprising a CVD diamond crystal where the free-exciton recombination radiation (235 nm) caused by current injection is dominant.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: March 7, 2006
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Takefumi Ishikura, Kenji Horiuchi, Satoshi Yamashita, Aki Kawamura, Kazuo Nakamura, Kenichi Nakamura, Takahiro Ide
  • Publication number: 20050128925
    Abstract: A signal detection sections detect the light intensity modulated by the phase pits as ROM signals from the return lights of an optical storage medium that has phase pits and a recording layer to simultaneously regenerate data in the ROM and RAM, and detect the RAM signals where the return lights were modulated by the recording film. A feedback circuit reduces the cross-talk of the phase pits of the RAM signals of the recording film by feeding back the ROM signals to the laser drive current of the laser element, and a circuit for adjusting the feedback circuit so as to present a constant cross-talk suppression effect regardless the temperature change of the laser element. Since the feedback gain is changed by changing the laser temperature, an RF feedback gain, with which MO signals are not deteriorated by the change of the laser temperature, can be set.
    Type: Application
    Filed: January 31, 2005
    Publication date: June 16, 2005
    Inventor: Satoshi Yamashita
  • Patent number: 6879385
    Abstract: A nondestructive reading method for an isotopic label, capable of easily and quickly reading information on an isotopic label imparted to an article in advance without destroying the label, and a nondestructive reading-use isotopic label suitably using this method. In addition, information obtained by this nondestructive reading method is used to easily and quickly judge the authenticity of an article.
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: April 12, 2005
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Tokudai Neda, Yasuharu Yokoi, Kenji Maeda, Kenji Horiuchi, Satoshi Yamashita
  • Patent number: 6872981
    Abstract: A diamond ultraviolet luminescent element (10) having a current-injection light-emitting diode structure includes a high-quality boron-doped p-type diamond crystal (semiconductor layer) (1) synthesized by the high pressure and high temperature method; a phosphorous-doped n-type diamond crystal (n-type semiconductor layer) (3) formed on the first diamond surface by the chemical vapor deposition; an electrode (5) formed on the surface of the n-type semiconductor layer (3); and an electrode (7) formed on the surface of the p-type semiconductor layer (1). The luminescence (235 nm) attributed to the recombination of free excitons resulting from current injection dominates in ultraviolet wavelength region (10).
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: March 29, 2005
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Kenji Horiuchi, Takefumi Ishikura, Satoshi Yamashita, Aki Kawamura, Kazuo Nakamura, Kenichi Nakamura, Takahiro Ide
  • Publication number: 20040190434
    Abstract: The present invention is intended to provide an information recording medium in which ID regions (identification regions) have a high recording density. The information recording medium according to the present invention has identification regions where identification information is recorded by means of protrusions and recesses provided on edges of the information storage stripe along the width of the information storage stripe.
    Type: Application
    Filed: July 24, 2003
    Publication date: September 30, 2004
    Applicant: FUJITSU LIMITED
    Inventor: Satoshi Yamashita
  • Publication number: 20030178561
    Abstract: A nondestructive reading method for an isotopic label, capable of easily and quickly reading information on an isotopic label imparted to an article in advance without destroying the label, and a nondestructive reading-use isotopic label suitably using this method. In addition, information obtained by this nondestructive reading method is used to easily and quickly judge the authenticity of an article.
    Type: Application
    Filed: March 11, 2003
    Publication date: September 25, 2003
    Inventors: Tokudia Neda, Yasuharu Yokoi, Kenji Maeda, Kenji Horiuchi, Satoshi Yamashita
  • Patent number: 6433474
    Abstract: A current injection-type diamond ultraviolet light-emitting device is provided that achieves the diamond free exciton recombination radiation by forming electrodes on a high-quality diamond crystal and applying a DC voltage between electrodes to inject carriers. A diamond crystal can be selected in terms of photoluminescent spectrum at room temperature and the half width of the Raman scattering peak intrinsic to the diamond.
    Type: Grant
    Filed: June 20, 2000
    Date of Patent: August 13, 2002
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Kenji Horiuchi, Kazuo Nakamura, Satoshi Yamashita
  • Patent number: 6392972
    Abstract: An optical storage unit which uses a light beam to record information on and/or reproduce information from a recording medium. The recording medium is provided with at least one land and at least one groove, and information is recorded in plural sectors in each of the land(s) and groove(s). The optical storage unit includes an optical phase adjuster for adjusting a phase of a polarization component of the light beam reflected from the recording medium based on a track type determination of a target address. An optical pickup is provided for reproducing information recorded on the recording medium using the phase-adjusted polarization component of the light beam.
    Type: Grant
    Filed: June 9, 1999
    Date of Patent: May 21, 2002
    Assignee: Fujitsu Limited
    Inventors: Satoshi Yamashita, Yasuaki Morimoto, Motohiro Ito
  • Patent number: 6363047
    Abstract: Disclosed is an optical recording medium processing apparatus which can reduce the noise included in a reproduction signal. According to the present invention, light returning from the pit area and light returning from the information signal area of a recording medium are identified, and an RF-Sum signal which corresponds to the level of light returning from the recording medium is used as an APC monitor signal for the information signal area.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: March 26, 2002
    Assignee: Fujitsu Limited
    Inventor: Satoshi Yamashita
  • Publication number: 20010001385
    Abstract: A 12C or 13C isotopic diamond which is boron-doped and has an extremely high thermal conductivity, and a process for producing the same. The purity of the 12C or 13C isotope of said isotopic diamond is preferably at least 99.5%.
    Type: Application
    Filed: December 8, 2000
    Publication date: May 24, 2001
    Applicant: TOKYO GAS CO., LTD
    Inventors: Kazuo Nakamura, Kenji Horiuchi, Satoshi Yamashita, Kazuhiro Kataoka
  • Patent number: 6153704
    Abstract: A thermoplastic elastomer composition prepared by dynamically treating with heat (a) an oil-extended ethylene-based copolymer rubber which comprises an ethylene-based copolymer rubber with an intrisic viscosity [.eta.] in the range from 4.3 to 6.8 dl/g when measured at 135.degree. C. in decalin and a mineral oil softening agent and (b) an olefin-based resin, in the presence of a crosslinking agent. The composition exhibits well-balanced and excellent elasticity recoverability and moldability, and can produce molded articles with superior appearance.
    Type: Grant
    Filed: January 19, 1999
    Date of Patent: November 28, 2000
    Assignee: JSR Corporation
    Inventors: Kazuhisa Kodama, Yoshihisa Mizuno, Hideo Nakanishi, Satoshi Yamashita, Kou Hasegawa, Kenji Yasuda
  • Patent number: 6060118
    Abstract: There is provided a diamond crystal in which the (111) oriented plane is of the diamond crystal synthesized on a substrate by a chemical vapor deposition method parallel to a substrate surface, and the area of the (111) oriented plane parallel to the substrate surface is 1/24or less an area of the crystal on the substrate. A source gas is activated on a substrate consisting of a material which is not reactive with carbon. The source gas contains at least carbon and hydrogen in such a manner that the ratio of the number of carbon atoms to the total number of molecules of the source gas is 0.5% or less. Subsequently, a diamond crystal in which the (111) orientation plane is parallel to the substrate surface, and the area of the (111) orientation plane parallel to the substrate surface is precipitated on the substrate. A copper plate is preferably contains used as the substrate.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: May 9, 2000
    Assignees: Tokyo Gas Co., Ltd., Tokyo Gas Chemicals Co., Ltd.
    Inventors: Takefumi Ishikura, Satoshi Yamashita, Shin-ichi Ojika, Hiroshi Kawarada
  • Patent number: 6025211
    Abstract: On the surface of a hydrogen-terminated diamond 1 formed by terminating a surface 2 of either a homoepitaxial diamond or a heteroepitaxial diamond or a surface-flattened polycrystal diamond are formed a drain-ohmic contact 4 and a source-ohmic contact 3 of gold or platinum, an insulating layer 5 formed of silicon oxide (SiO.sub.x : 1.ltoreq.X.ltoreq.2) and a gate electrode 6 mounted on said insulating layer, and the surface other than the element forming region is set to be an insulating region being non-hydrogen-terminated, for example, oxygen-terminated, and the elements formed on said region is being isolated.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: February 15, 2000
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Takefumi Ishikura, Satoshi Yamashita, Hiroshi Kawarada, Akira Hokazono
  • Patent number: 5854496
    Abstract: On the surface of a hydrogen-terminated diamond 1 formed by terminating a surface 2 of either a homoepitaxial diamond or a heteroepitaxial diamond or a surface-flattened polycrystal diamond are formed a drain-ohmic contact 4 and a source-ohmic contact 3 of gold or platinum, an insulating layer 5 formed of silicon oxide (SiO.sub.x : 1.ltoreq.X.ltoreq.2) and a gate electrode 6 mounted on said insulating layer, and the surface other than the element forming region is set to be an insulating region being non-hydrogen-terminated, for example, oxygen-terminated, and the elements formed on said region is being isolated.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: December 29, 1998
    Assignee: Tokyo Gas Co., Ltd.
    Inventors: Takefumi Ishikura, Satoshi Yamashita, Hiroshi Kawarada, Akira Hokazono
  • Patent number: 5796643
    Abstract: A digital filter with a reduced filtering time. On/off data provided by eight contacts are read at predetermined time intervals, and the on/off data are stored in 8-bit binary data. (four-to one-cycle-previous data and new data). Logical AND and logical OR between the data are carried out to obtain AND result X and OR result Z, logical operations between the previous result In-1 and AND result X is carried out to obtain a result Y, and logical AND between the result Y and the OR result Z is carried out. A bit "A" whose AND result X is "1" is set again to "1", and a bit B whose OR result Z is "0" is set again to "0".
    Type: Grant
    Filed: January 2, 1996
    Date of Patent: August 18, 1998
    Assignee: Allen-Bradley Company, LLC
    Inventors: Tomoyuki Nanami, Satoshi Yamashita, Dennis M. Wright, Kendal R. Harris