Patents by Inventor Naomasa Nakamura

Naomasa Nakamura 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: 8179765
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 26, 2011
    Date of Patent: May 15, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8174948
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: May 8, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8169873
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: May 1, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8169872
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: May 1, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8169874
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: May 1, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8165001
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 24, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8165000
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 24, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8159920
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 17, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8159921
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 17, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8154971
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 25, 2011
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8154970
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8149674
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: April 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8149672
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: April 3, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8137894
    Abstract: According to an embodiment, a storage medium includes a transparent resin substrate having a concentric or spiral groove and a recording film formed on the groove on the transparent resin substrate, a recording mark being formed by irradiation of a laser beam, wherein a reproduction durability count in a case where reproduction is continuously carried out by a laser beam is 1,000,000 or more.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: March 20, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Seiji Morita, Koji Takazawa, Kazuyo Umezawa, Hideo Ando, Yasuaki Ootera, Naoki Morishita, Naomasa Nakamura
  • Patent number: 8139459
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: March 20, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8134899
    Abstract: According to one embodiment, an optical recording medium is provided in which interlayer crosstalk is low and in which stable and high-quality recording characteristics can be obtained. To this end, an optical recording medium comprises a first recording part which includes a first recording layer and a first light reflecting layer and which is disposed on a side closer to a light receiving surface, and a second recording part which includes a second recording layer and a second light reflecting layer and which is disposed on a side farther from the light receiving surface, the first recording part and the second recording part being stacked, wherein the thickness of the second light reflecting layer is larger than the thickness of the first light reflecting layer.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: March 13, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Publication number: 20120026851
    Abstract: An optical recording medium including a plurality of recording layers to record/reproduce information using light with a predetermined wavelength, the information being recorded on one of the recording layers using a mark and a space, wherein a channel clock period T is provided for recording the mark on one of the recording layers. A plurality of pulses, including a last pulse arranged at an end of the pulses, are used to record the mark with length 3T, the mark being recorded with a condition that a width of the last pulse is minimum 0T and maximum 1.10T, in which a first subsequent level lower than a peak power level of the last pulse is arranged next to the last pulse, and a second subsequent level lower than the peak power level but higher than the first subsequent level is arranged next to the first subsequent level.
    Type: Application
    Filed: October 4, 2011
    Publication date: February 2, 2012
    Inventors: Kazuyo UMEZAWA, Seiji Morita, Koji Takazawa, Naomasa Nakamura, Naoki Morishita, Shinichi Katsuda
  • Publication number: 20120026854
    Abstract: An optical recording medium including a plurality of recording layers to record/reproduce information using light with a predetermined wavelength, the information being recorded on one of the recording layers using a mark and a space, wherein a channel clock period T is provided for recording the mark on one of the recording layers. A plurality of pulses, including a last pulse arranged at an end of the pulses, are used to record the mark with length 3T, the mark being recorded with a condition that a width of the last pulse is minimum OT and maximum 1.10T, in which a first subsequent level lower than a peak power level of the last pulse is arranged next to the last pulse, and a second subsequent level lower than the peak power level but higher than the first subsequent level is arranged next to the first subsequent level.
    Type: Application
    Filed: October 4, 2011
    Publication date: February 2, 2012
    Inventors: Kazuyo UMEZAWA, Seiji Morita, Koji Takazawa, Naomasa Nakamura, Naoki Morishita, Shinichi Katsuda
  • Patent number: 8059523
    Abstract: An optical recording medium including a plurality of recording layers to record/reproduce information using light with a predetermined wavelength, the information being recorded on one of the recording layers using a mark and a space, wherein a channel clock period T is provided for recording the mark on one of the recording layers. A plurality of pulses, including a last pulse arranged at an end of the pulses, are used to record the mark with length 3T, the mark being recorded with a condition that a width of the last pulse is minimum 0T and maximum 1.10T, in which a first subsequent level lower than a peak power level of the last pulse is arranged next to the last pulse, and a second subsequent level lower than the peak power level but higher than the first subsequent level is arranged next to the first subsequent level.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: November 15, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Koji Takazawa, Naomasa Nakamura, Naoki Morishita, Shinichi Katsuda
  • Publication number: 20110222381
    Abstract: Manufacturing of a higher quality write-once type multilayer optical disc is facilitated. The optical disc includes a plurality of recording layers in which recording or reproduction is carried out by a blue or blue-violet laser beam of a wavelength of about 405 nm. Each of the recording layers includes a recording layer which uses an organic dye. The plurality of recording layers includes a layer in which a groove pattern around a recording mark is deformed when information is recorded, and a layer in which the groove pattern around the recording mark is not deformed when information is recorded.
    Type: Application
    Filed: May 20, 2011
    Publication date: September 15, 2011
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Yasuaki Ootera, Kazuyo Umezawa, Koji Takazawa, Naoki Morishita, Hideo Ando, Seiji Morita, Naomasa Nakamura