Patents by Inventor Akira Shirota

Akira Shirota 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).

  • Publication number: 20090052302
    Abstract: A recording apparatus includes: a recording device for recording data onto each of a plurality of types of recording media by irradiating a light beam corresponding to each of the types of recording media; a diffracting device disposed on an optical path of the light beam from the recording device to the recording medium, for generating a main beam and a plurality of sub beams by diffracting the optical beam, the main beam recording data and performing a tracking process, the sub beams performing the tracking process, an amplitude of a tracking signal generated by each or one portion of the sub beams and by the main beam being maximum; a controlling device for controlling the diffracting device to adjust a position on which each of the plurality of sub beams is focused, in accordance with the type of the recording medium; and a tracking device.
    Type: Application
    Filed: April 13, 2006
    Publication date: February 26, 2009
    Applicant: PIONEER CORPORATION
    Inventors: Naoharu Yanagawa, Akira Shirota
  • Patent number: 7474601
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Grant
    Filed: February 7, 2007
    Date of Patent: January 6, 2009
    Assignee: Pioneer Corporation
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20090003175
    Abstract: An information recording apparatus (300) is provided with: a first recording device (302 etc.) for recording the first information into a first area of the first layer; a second recording device (302 etc.) for recording the second information into a predetermined area of the second layer; and a controlling device (305) for controlling the second recording device to record the second information by the laser light, while displacing an edge indicating an innermost or outermost circumference of the predetermined area in which a penetrated area penetrated by the laser light is included in the first area, in a direction to approach an edge of the predetermined area in which the penetrated area is not included in the first area, only by a predetermined length corresponding to a tolerance of a change amount indicating a change in the reproduction quality.
    Type: Application
    Filed: January 13, 2006
    Publication date: January 1, 2009
    Applicant: PIONEER CORPORATION
    Inventors: Eisaku Kawano, Masahiro Kato, Akira Shirota, Masahiro Miura, Tohru Kanegae, Shoji Taniguchi, Eiji Muramatsu
  • Patent number: 7349316
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Grant
    Filed: October 5, 2006
    Date of Patent: March 25, 2008
    Assignee: Pioneer Corporation
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20080043584
    Abstract: In an information recording medium including at least a first recording layer (L0 layer) capable of recording information and a second recording layer (L1 layer) capable of recording information, an information recording device (300) records information in a predetermined area (12) of the second recording layer by a laser beam which has passed through a transmission area (11) of the first recording layer. The information recording medium (300) includes recording means (302, etc.) for recording the information in the first recording layer or the second recording layer, judgment means for judging whether an unrecorded amount indicating the size of the unrecorded area in the radial direction in the transmission area is smaller than a predetermined amount, and control means used when the unrecorded area is judged to be smaller than the predetermined amount, for controlling the recording means to record information in the predetermined area.
    Type: Application
    Filed: January 13, 2006
    Publication date: February 21, 2008
    Applicant: Pioneer Corporation
    Inventors: Eisaku Kawano, Masahiro Kato, Akira Shirota, Masahiro Miura, Tohru Kanegae, Shoji Taniguchi, Eiji Muramatsu
  • Publication number: 20070223340
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Application
    Filed: February 7, 2007
    Publication date: September 27, 2007
    Applicant: PIONEER CORPORATION
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Patent number: 7274644
    Abstract: When a bias power level of a recording pulse waveform is varied entirely or partially, a shape of the recording pulse wave form is varied according to the variation. For example, when the bias power level is increased, a width or an edge position of a top pulse or a multi-pulse of the recording pulse waveform is varied correspondingly. Thereby, a total heat quantity of a recording laser light is not increased, and a preferable recording characteristic is maintained.
    Type: Grant
    Filed: August 27, 2003
    Date of Patent: September 25, 2007
    Assignee: Pioneer Corporation
    Inventors: Kunihiko Horikawa, Akira Shirota, Masahiro Kato, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20070217310
    Abstract: The present invention provides a recording pulse generating apparatus capable of forming a recording pit having a proper shape even at the time of ultra-high-speed recording of, for example, 8×recording or higher. A recording controller 10 for generating recording pulse signals having lengths corresponding to ten kinds of lengths of pits formed at the time of recording information has a recording controller 10 for generating the recording pulse signals so that the amplitude of a recording pulse signal corresponding to a pit having a length of 4T changes from a first amplitude to a second amplitude, and generating the recording pulse signals so that the amplitude of a recording pulse signal corresponding to a pit having a length of 5T or longer changes from a third amplitude to a fourth amplitude and further changes to a fifth amplitude.
    Type: Application
    Filed: March 30, 2005
    Publication date: September 20, 2007
    Inventors: Akira Shirota, Kunihiko Horikawa, Hiroyuki Uchino, Yoshio Sasaki, Shoji Taniguchi, Eiji Muramatsu
  • Publication number: 20070217311
    Abstract: The present invention provides a recording pulse generating apparatus capable of forming a recording pit having a proper shape even at the time of ultra-high-speed recording of, for example, 8× recording or higher. A recording controller 10 for generating recording pulse signals having lengths corresponding to ten kinds of lengths of pits formed at the time of recording information has a recording controller 10 for generating the recording pulse signals so that the amplitude of a recording pulse signal corresponding to a pit having a length of 4 T changes from a first amplitude to a second amplitude, and generating the recording pulse signals so that the amplitude of a recording pulse signal corresponding to a pit having a length of 5 T or longer changes from a third amplitude to a fourth amplitude and further changes to a fifth amplitude.
    Type: Application
    Filed: March 29, 2007
    Publication date: September 20, 2007
    Inventors: Akira Shirota, Kunihiko Horikawa, Hiroyuki Uchino, Yoshio Sasaki, Shoji Taniguchi, Eiji Muramatsu
  • Publication number: 20070195678
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Application
    Filed: February 7, 2007
    Publication date: August 23, 2007
    Applicant: PIONEER CORPORATION
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20070133369
    Abstract: An information recording device and method capable of forming a recording mark by suppressing thermal interference. The device applies a laser beam to a recording medium and forms a recording mark in accordance with a recording signal. The device includes a light source for emitting the laser beam, signal generation elements for generating a recording pulse signal according to the recording signal, and drive elements for driving the light source according to the recording pulse signal. The recording pulse signal has a mark period for forming the recording mark and a space period. The recording pulse signal makes the level in the entire space period equal to or shorter than a predetermined length and a part of the space period longer than the predetermined length to be off level. While the recording pulse signal is off level, the recording medium is cooled down, thereby suppressing the affect of thermal interference.
    Type: Application
    Filed: October 26, 2004
    Publication date: June 14, 2007
    Inventors: Kunihiko Horikawa, Akira Shirota, Hiroyuki Uchino, Shoji Taniguchi, Eiji Muramatsu
  • Publication number: 20070109938
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Application
    Filed: October 5, 2006
    Publication date: May 17, 2007
    Applicant: PIONEER CORPORATION
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20070109934
    Abstract: An information recording apparatus (300) is provided with: a recording device (352) for irradiating an information recording medium (100) with laser light and for recording information onto the information recording medium; an obtaining device (354) for obtaining at least one of (i) a special OPC strategy for defining a waveform of the laser light used to calculate an optimum laser power of the laser light for recording the information at a second recording speed different from a first recording speed, at the first recording speed, and (ii) a recording strategy for defining a waveform of the laser light used to record the information at the second recording speed; a power calculating device (354) for calculating the optimum laser power by using the special OPC strategy at the first recording speed; and a controlling device (354) for controlling said recording device to record the information at the second recording speed, by using the calculated optimum laser power and the recording strategy.
    Type: Application
    Filed: September 29, 2004
    Publication date: May 17, 2007
    Applicant: PIONEER CORPORATION
    Inventors: Kunihiko Horikawa, Hiroyuki Uchino, Shoji Taniguchi, Akira Shirota, Yoshio Sasaki, Eiji Muramatsu
  • Patent number: 7161888
    Abstract: Based on a recording signal, a recording pulse signal, which includes a top pulse located at a front end portion and having a first magnitude, a last pulse located at a back end portion and having the first magnitude, and an intermediate bias portion located between the top pulse and the last pulse and having a second magnitude, is generated. Based on the recording pulse signal, a light source is controlled, and a laser pulse is irradiated on a recording medium. Recording marks corresponding to the recording signal are formed on the recording medium. In generating the recording pulse signal, when the recording medium is rotationally driven, a position of the top pulse is shifted ahead of a position of the top pulse when the recording medium is rotationally driven at the first rotation speed, when the recording medium is rotationally driven at the second control speed.
    Type: Grant
    Filed: April 2, 2003
    Date of Patent: January 9, 2007
    Assignee: Pioneer Corporation
    Inventors: Kunihiko Horikawa, Shoji Taniguchi, Eiji Muramatsu, Akira Shirota
  • Patent number: 7139230
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: November 21, 2006
    Assignee: Pioneer Corporation
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20060120232
    Abstract: A tracking servo control device for making a tracking servo control to apply a light beam onto a groove track on a recording medium where the groove track and a pre-pit are preformed, is provided with: a first generation device which generates a first regenerative signal based on a reflected light from the recording medium when at least a part of the pre-pit is formed within a radiation range of the light beam onto the groove track; a second generation device which generates a second regenerative signal based on a reflected light from the recording medium when the pre-pit is formed outside the radiation range of the light beam; and a calculation device which calculates an offset value in the tracking servo control based on the first regenerative signal and the second regenerative signal that are generated.
    Type: Application
    Filed: December 25, 2003
    Publication date: June 8, 2006
    Inventors: Naoharu Yanagawa, Tatsuhiro Yone, Masahiro Kato, Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu
  • Publication number: 20060098547
    Abstract: Based on a recording signal, a recording pulse signal, which includes a top pulse located at a front end portion and having a first magnitude, a last pulse located at a back end portion and having the first magnitude, and an intermediate bias portion located between the top pulse and the last pulse and having a second magnitude, is generated. Based on the recording pulse signal, a light source is controlled, and a laser pulse is irradiated on a recording medium. Recording marks corresponding to the recording signal are formed on the recording medium. In generating the recording pulse signal, when the recording medium is rotationally driven, a position of the top pulse is shifted ahead of a position of the top pulse when the recording medium is rotationally driven at the first rotation speed, when the recording medium is rotationally driven at the second control speed.
    Type: Application
    Filed: April 2, 2003
    Publication date: May 11, 2006
    Inventors: Kunihiko Horikawa, Shoji Taniguchi, Eiji Muramatsu, Akira Shirota
  • Publication number: 20060007832
    Abstract: When a bias power level of a recording pulse waveform is varied entirely or partially, a shape of the recording pulse wave form is varied according to the variation. For example, when the bias power level is increased, a width or an edge position of a top pulse or a multi-pulse of the recording pulse waveform is varied correspondingly. Thereby, a total heat quantity of a recording laser light is not increased, and a preferable recording characteristic is maintained.
    Type: Application
    Filed: August 27, 2003
    Publication date: January 12, 2006
    Inventors: Kunihiko Horikawa, Akira Shirota, Masahiro Kato, Eiji Muramatsu, Shoji Taniguchi
  • Publication number: 20060002250
    Abstract: An information recording apparatus is provided with: an optical head which can optically write information onto an information recording medium; a focusing device for performing such focusing that a focus position of the optical head is set onto a recording reference plane of the information recording medium; and a controlling device for controlling the focusing device to shift the focus position from the recording reference plane by an offset value in order to correct an influence of aberration and controlling the optical head to perform writing in such a condition that the focus position is shifted.
    Type: Application
    Filed: July 1, 2005
    Publication date: January 5, 2006
    Applicant: Pioneer Corporation
    Inventors: Akira Shirota, Masahiro Kato, Kunihiko Horikawa
  • Publication number: 20030067857
    Abstract: The information recording apparatus irradiates a laser beam on a recording medium such as an optical disk and forms a recording mark corresponding to a recording signal to record information. A recording pulse signal includes a mark period irradiating the laser beam for forming the recording mark and a space period in which the recording mark is not formed. The mark period has a top pulse period and an intermediate bias period following the top pulse period. The mark period constituted by the top pulse period and the intermediate bias period does not have a continuous part of a plurality of pulses having a small pulse width unlike a pulse train, so that the correct recording mark can be stably formed on the recording medium without an inadequate deformation of a recording pulse shape, even in the case of a high speed recording.
    Type: Application
    Filed: September 10, 2002
    Publication date: April 10, 2003
    Inventors: Akira Shirota, Kunihiko Horikawa, Eiji Muramatsu, Shoji Taniguchi