Patents by Inventor Takehiko Yorozu

Takehiko Yorozu 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: 6529466
    Abstract: An information recording apparatus for recording data by applying energy to a recording medium to form thereon local physical changes of the medium includes a total energy irradiating amount discriminating unit for discriminating a total energy irradiating amount of each mark and each space when data is recorded, and a recording energy irradiating unit for switching between at least two levels of the total energy irradiating amount during a mark non-forming period, in accordance with results discriminated by the total energy irradiating amount discriminating unit. The at least two levels may be at least two mutually different levels.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: March 4, 2003
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6512726
    Abstract: An information recording apparatus for recording data by applying energy to a recording medium to form thereon local physical changes of the medium includes a space length discriminating unit for discriminating a space length of a space in a channel data sequence when data is recorded, and a recording energy irradiating unit for generating at least two recording waveforms when successive spaces having a same length in the channel data sequence are recorded, in accordance with results discriminated by the space length discriminating unit. The at least two recording waveforms may be at least two mutually different recording waveforms.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: January 28, 2003
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6430132
    Abstract: An information recording apparatus capable of forming a fine mark reliably and highly precisely through compensation for thermal interference and heat accumulation. The information recording apparatus is provided with a recording energy irradiating unit for generating at least two recording waveforms when marks of the same length or spaces of the same length in a channel data sequence are recorded. The information recording apparatus constructed as above can realize highly reliable recording/reproducing operations and can be made compact at a low cost with a large storage capacity.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: August 6, 2002
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6404716
    Abstract: An information recording apparatus capable of forming a fine mark reliably and highly precisely through compensation for thermal interference and heat accumulation. The information recording apparatus is provided with a recording energy irradiating unit for generating at least two recording waveforms when marks of the same length or spaces of the same length in a channel data sequence are recorded. The information recording apparatus constructed as above can realize highly reliable recording/reproducing operations and can be made compact at a low cost with a large storage capacity.
    Type: Grant
    Filed: November 16, 2000
    Date of Patent: June 11, 2002
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6383595
    Abstract: An information recording medium having recording, reproducing, and rewriting characteristics better than those of prior art media. The media has a recording layer made of a material represented by the following formula: Gex−wSbyTezMw, wherein 0.13≦x≦0.22, 0.20≦y≦0.32, 0.53≦z≦0.60, 0≦w≦0.06, x+y+z=1, and M is any one of Na, Mg, Al, P, S, Cl, L, Ca, Sc, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Nb, Ru, Rh, Cd, In, Sn, I, Cs, Ba, La, Hf, Ta, Re, Os, Ir, Hg, Tl, Pb, Th, U, Ag, Cr, W, Mo, Pt, Co, Ni, Pd, Si, Au, Cu, V, Mn, Fe, Ti and Bi.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: May 7, 2002
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Akemi Hirotsune, Motoyasu Terao, Makoto Miyamoto, Yasushi Miyauchi, Tetsuya Nishida, Keikichi Ando, Nobuhiro Tokushuku, Yukio Fukui, Takehiko Yorozu, Reiji Tamura, Yoshihiro Ikari
  • Publication number: 20020041553
    Abstract: An information recording apparatus for recording data by applying energy to a recording medium to form thereon local physical changes of the medium includes a total energy irradiating amount discriminating unit for discriminating a total energy irradiating amount of each mark and each space when data is recorded, and a recording energy irradiating unit for switching between at least two levels of the total energy irradiating amount during a mark non-forming period, in accordance with results discriminated by the total energy irradiating amount discriminating unit. The at least two levels may be at least two mutually different levels.
    Type: Application
    Filed: December 18, 2001
    Publication date: April 11, 2002
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Publication number: 20020041558
    Abstract: An information recording apparatus for recording data by applying energy to a recording medium to form thereon local physical changes of the medium includes a space length discriminating unit for discriminating a space length of a space in a channel data sequence when data is recorded, and a recording energy irradiating unit for generating at least two recording waveforms when successive spaces having a same length in the channel data sequence are recorded, in accordance with results discriminated by the space length discriminating unit. The at least two recording waveforms may be at least two mutually different recording waveforms.
    Type: Application
    Filed: December 18, 2001
    Publication date: April 11, 2002
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6188658
    Abstract: An information recording apparatus capable of forming a fine mark reliably and highly precisely through compensation for thermal interference and heat accumulation. The information recording apparatus is provided with a recording energy irradiating unit for generating at least two recording waveforms when marks of the same length or spaces of the same length in a channel data sequence are recorded. The information recording apparatus constructed as above can realize highly reliable recording/reproducing operations and can be made compact at a low cost with a large storage capacity.
    Type: Grant
    Filed: May 18, 2000
    Date of Patent: February 13, 2001
    Assignees: Hitachi, Ltd., Hitachi Maxell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 6104685
    Abstract: An information recording apparatus capable of forming a fine mark reliably and highly precisely through compensation for thermal interference and heat accumulation. The information recording apparatus is provided with a recording energy irradiating unit for generating at least two recording waveforms when marks of the same length or spaces of the same length in a channel data sequence are recorded. The information recording apparatus constructed as above can realize highly reliable recording/reproducing operations and can be made compact at a low cost with a large storage capacity.
    Type: Grant
    Filed: December 22, 1997
    Date of Patent: August 15, 2000
    Assignees: Hitachi, Ltd., Hitachi Maxwell, Ltd.
    Inventors: Hideki Saga, Hirofumi Sukeda, Takehiko Yorozu
  • Patent number: 5598399
    Abstract: A magneto-optic recording medium comprises on a substrate the first dielectric substance layer, a magneto-optic recording layer, the second dielectric substance layer and a reflective layer. The magneto-optic recording layer has, in the range of the Curie temperature Tc to (Tc-50) .degree.C., a value of a product of a saturated magnetization Ms and a coercive force Hc of not more than 4.times.10.sup.4 erg/cm.sup.3. The magneto-optic recording medium can be recorded at a magnetic field as low as 100 (Oe) with an excellent C/N.
    Type: Grant
    Filed: August 24, 1995
    Date of Patent: January 28, 1997
    Assignee: Hitachi Maxell, Ltd.
    Inventors: Noriyuki Ogihara, Yoshinori Shirai, Takehiko Yorozu