Patents by Inventor Kazuyo Umezawa

Kazuyo Umezawa 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: 8252510
    Abstract: According to one embodiment, a write-once type information storage medium comprises an organic dye based recording material having sensitivity at a wavelength of 405 nm and at a recording wavelength in the range of 600 nm to 700 nm, wherein, when absorbance of a maximum absorption wavelength in the vicinity of 405 nm is defined as 1, the absorbance is 5% or more at any wavelength in the range of 600 nm to 700 nm.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: August 28, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Hideo Ando, Seiji Morita, Koji Takazawa, Yasuaki Ootera, Naoki Morishita, Kazuyo Umezawa
  • Patent number: 8238224
    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: Grant
    Filed: October 4, 2011
    Date of Patent: August 7, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Koji Takazawa, Naomasa Nakamura, Naoki Morishita, Shinichi Katsuda
  • Publication number: 20120195179
    Abstract: According to one embodiment, a re-recordable write-once optical disc by which recording/reproducing can be properly done with a short-wavelength blue laser is provided. The disc has recording layers on which marks are recorded by the laser power of a modulated short wavelength, with a space formed between the recorded marks. The recording layer of the disc uses an organic dye material by which no physical modification or no physical change substantially occurs in an area of the recorded marks.
    Type: Application
    Filed: April 10, 2012
    Publication date: August 2, 2012
    Inventors: Kazuyo UMEZAWA, Seiji Morita, Koji Takazawa, Hideo Ando, Yasuaki Ootera, Naomasa Nakamura, Naoki Morishita
  • Patent number: 8232042
    Abstract: According to one embodiment, a storage medium comprises a transparent resin substrate on which a groove is formed, a recording layer formed on the groove on the transparent resin substrate, the recording layer using an organic dye material and recording information with a light beam of 620 nm or less in wavelength, a reflection layer formed on the recording layer, and a prevention layer formed between the recording layer and the reflection layer, the prevention layer preventing degradation of characteristics of the reflection layer.
    Type: Grant
    Filed: March 30, 2006
    Date of Patent: July 31, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Nakai, Seiji Morita, Koji Takazawa, Yasuaki Ootera, Naoki Morishita, Kazuyo Umezawa, Hideo Ando
  • Patent number: 8218416
    Abstract: According to one embodiment, single-sided dual-layer recordable disc 100 may be used. Information recording is performed by forming mark and space portions on data area DA using modulated laser power. Pp denotes the maximum laser power or peak power for forming the mark portion, and Pb denotes the bias power for forming the space portion. Power ratio Pb/Pp is calculated for each of recording layers L0 and L1. Information is recorded on any of the recording layers L0 and L1 based on the result of calculation. Here, the calculated power ratio Pb/Pp changes among the recording layers L0 and L1, thereby optimizing the recording condition for a multi-layer recordable optical disc within relatively short time.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: July 10, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Koji Takazawa, Hideo Ando, Yasuaki Ootera, Naomasa Nakamura, Naoki Morishita
  • Patent number: 8184517
    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 22, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • Patent number: 8179764
    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 15, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Koji Takazawa, Seiji Morita, Kazuyo Umezawa, Naoki Morishita, Yasuaki Ootera, Hideo Ando, Naomasa Nakamura
  • 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: 8179763
    Abstract: According to one embodiment, a re-recordable write-once optical disc by which recording/reproducing can be properly done with a short-wavelength blue laser is provided. The disc has recording layers on which marks are recorded by the laser power of a modulated short wavelength, with a space formed between the recorded marks. The recording layer of the disc uses an organic dye material by which no physical modification or no physical change substantially occurs in an area of the recorded marks.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: May 15, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Koji Takazawa, Hideo Ando, Yasuaki Ootera, Naomasa Nakamura, Naoki Morishita
  • 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: 8173029
    Abstract: According to one embodiment, a cured first ultraviolet-curing resin material layer having a first three-dimensional pattern is formed on a first principal surface of a magnetic recording medium having a central hole. A cured second ultraviolet-curing resin material layer having a second three-dimensional pattern is formed on a second principal surface opposite to the first principal surface of the magnetic recording.
    Type: Grant
    Filed: March 16, 2010
    Date of Patent: May 8, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Seiji Morita, Shinobu Sugimura, Kazuyo Umezawa, Masatoshi Sakurai
  • 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: 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: 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: 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: 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: 8159767
    Abstract: According to one embodiment, a stamper has three-dimensional patterns in a dummy region. The three-dimensional patterns have a repeatable run out of 1 nm or less between the 15th and 40th orders when the rotational frequency is the first order as a reference.
    Type: Grant
    Filed: August 10, 2009
    Date of Patent: April 17, 2012
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuyo Umezawa, Seiji Morita, Masatoshi Sakurai
  • 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: 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