Patents by Inventor Michihisa Takahashi

Michihisa Takahashi 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).

  • Initialization of phase-change optical recording medium
    Patent number: 6445669
    Abstract: A method of initializing a phase-change optical information recording medium is provided, using an optical system incorporating a semiconductor laser device. The laser device is characterized by a specified spatial power distribution. In a spatial distribution of the laser power focused on the recording medium, in the direction perpendicular to guide tracks the laser device preferably has less average smaller in both end regions of the spatial distribution, which have each 10% of the width at half maximum of the distribution, than the average in the center region of the full width at half maximum of the distribution.
    Type: Grant
    Filed: December 23, 1999
    Date of Patent: September 3, 2002
    Assignee: Ricoh Company, Ltd.
    Inventors: Kyohji Hattori, Fumiya Ohmi, Kenichi Aihara, Katsuyuki Yamada, Yuki Nakamura, Eiji Noda, Michihisa Takahashi, Yujiro Kaneko, Yukio Ide
  • Diazo-type thermosensitive recording material with hydrazone coupler and chelating metal compound
    Patent number: 4659644
    Abstract: A diazo-type thermosensitive recording material is disclosed, which comprises a support material and a thermosensitive coloring layer formed on the support material, which thermosensitive coloring layer comprises a diazonium compound, a coupler and a thermo-fusible or thermo-softening material, the coupler being a combination of a hydrazone-type coupler of the formula of R.sup.1 --NH--N.dbd.CH--R.sup.2 (wherein R.sup.1 and R.sup.2 are defined in detail in the specification) and a two-valence metal compound capable of chelating with the coupled product produced by the coupling of the diazonium compound and the hydrazone-type coupler.
    Type: Grant
    Filed: December 19, 1984
    Date of Patent: April 21, 1987
    Assignee: Ricoh Company, Ltd.
    Inventors: Takayuki Hoshina, Michihisa Takahashi, Masanori Rimoto, Masanaka Nagamoto
  • Catalyst bed for use in decomposition of ammonia gas
    Patent number: 4179407
    Abstract: Catalyst bed for use in decomposition of ammonia gas, which comprises a mixture of catalysts for use in decomposition of ammonia gas and granules of catalytically inert substances.
    Type: Grant
    Filed: May 25, 1978
    Date of Patent: December 18, 1979
    Assignee: Ricoh Co., Ltd.
    Inventors: Kiyotaka Iiyama, Takeshi Matsui, Shigeru Kusakata, Hideo Watanabe, Michihisa Takahashi
  • Developing apparatus for diazo copying machine
    Patent number: 4056824
    Abstract: A developing chamber and inlet and outlet chambers leading to and from the developing chamber respectively are uniformly heated in such a manner that ammonia gas used as a developing agent and water vapor are prevented from being condensed and contaminating copy sheets.
    Type: Grant
    Filed: September 1, 1976
    Date of Patent: November 1, 1977
    Assignee: Ricoh Company, Ltd.
    Inventors: Kiyotaka Iiyama, Takeshi Matsui, Shigeru Kusakata, Michihisa Takahashi
  • Initialization of phase-change optical recording medium
    Patent number: RE39901
    Abstract: A method of initializing a phase-change optical information recording medium is provided, using an optical system incorporating a semiconductor laser device. The laser device is characterized by a specified spatial power distribution. In a spatial distribution of the laser power focused on the recording medium, in the direction perpendicular to guide tracks the laser device preferably has less average smaller in both end regions of the spatial distribution, which have each 10% of the width at half maximum of the distribution, than the average in the center region of the full width at half maximum of the distribution.
    Type: Grant
    Filed: April 14, 2004
    Date of Patent: October 30, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Kyohji Hattori, Fumiya Ohmi, Kenichi Aihara, Katsuyuki Yamada, Yuki Nakamura, Eiji Noda, Michihisa Takahashi, Yujiro Kaneko, Yukio Ide