Patents by Inventor Tomotada Kamei

Tomotada Kamei 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: 20100149949
    Abstract: An optical pickup according to the present invention includes an integrated circuit element (LDD) 5 for driving first, second, and third semiconductor lasers 3, 4, and 5. The LDD 50 is shaped so as to have a rectangular principal face surrounded by one side, with a plurality of input/output pins being arranged along each side. The plurality of input/output pins include a first pin group connected to a blue-violet laser 5 whose oscillation wavelength is the shortest, a second pin group connected to a red laser 4, and a third pin group connected to an infrared laser 3. The wiring structure of the optical pickup includes a first transmission line 41 for connecting the first pin group to the blue-violet laser 5, a second transmission line 33 for connecting the second pin group to the red laser 4, and a third transmission line 31 for connecting the third pin group to the infrared laser 3, where the first transmission line 41 is shorter than both the second and third transmission lines 31 and 33.
    Type: Application
    Filed: February 25, 2010
    Publication date: June 17, 2010
    Inventors: Hisashi Senga, Tomotada Kamei, Kenzo Ishibashi, Hideki Hayashi, Yohichi Saitoh
  • Publication number: 20100103805
    Abstract: A semiconductor laser driving device is provided with a high frequency superimposing circuit (3) for superimposing a frequency current onto a laser driving current (6) of a semiconductor laser (1) provided in an optical head device; and a high frequency superimposition control circuit (5) which controls the frequency of the high frequency current corresponding to the temperature of the semiconductor laser (1).
    Type: Application
    Filed: September 19, 2006
    Publication date: April 29, 2010
    Inventors: Hiroaki Yoshida, Hideki Hayashi, Tomotada Kamei
  • Patent number: 7697400
    Abstract: An optical pickup according to the present invention includes an integrated circuit element (LDD) 5 for driving first, second, and third semiconductor lasers 3, 4, and 5. The LDD 50 is shaped so as to have a rectangular principal face surrounded by one side, with a plurality of input/output pins being arranged along each side. The plurality of input/output pins include a first pin group connected to a blue-violet laser 5 whose oscillation wavelength is the shortest, a second pin group connected to a red laser 4, and a third pin group connected to an infrared laser 3. The wiring structure of the optical pickup includes a first transmission line 41 for connecting the first pin group to the blue-violet laser 5, a second transmission line 33 for connecting the second pin group to the red laser 4, and a third transmission line 31 for connecting the third pin group to the infrared laser 3, where the first transmission line 41 is shorter than both the second and third transmission lines 31 and 33.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: April 13, 2010
    Assignee: Panasonic Corporation
    Inventors: Hisashi Senga, Tomotada Kamei, Kenzo Ishibashi, Hideki Hayashi, Yohichi Saitoh
  • Patent number: 7558162
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: July 7, 2009
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Patent number: 7558170
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: July 7, 2009
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20090168823
    Abstract: A semiconductor laser device according to the present invention includes: at least one laser chip that emits a laser beam; a plurality of lead pins that are electrically connected to the laser chip and that supply current to get the laser beam emitted; and a stem that holds the laser chip and the lead pins thereon. The lead pins have mutually different lengths and the longest one of the lead pins is electrically connected to the stem.
    Type: Application
    Filed: May 1, 2007
    Publication date: July 2, 2009
    Inventor: Tomotada Kamei
  • Patent number: 7542382
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: June 2, 2009
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Patent number: 7539090
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: May 26, 2009
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20090052492
    Abstract: An optical pickup according to the present invention includes an integrated circuit element (LDD) 5 for driving first, second, and third semiconductor lasers 3, 4, and 5. The LDD 50 is shaped so as to have a rectangular principal face surrounded by one side, with a plurality of input/output pins being arranged along each side. The plurality of input/output pins include a first pin group connected to a blue-violet laser 5 whose oscillation wavelength is the shortest, a second pin group connected to a red laser 4, and a third pin group connected to an infrared laser 3. The wiring structure of the optical pickup includes a first transmission line 41 for connecting the first pin group to the blue-violet laser 5, a second transmission line 33 for connecting the second pin group to the red laser 4, and a third transmission line 31 for connecting the third pin group to the infrared laser 3, where the first transmission line 41 is shorter than both the second and third transmission lines 31 and 33.
    Type: Application
    Filed: February 17, 2006
    Publication date: February 26, 2009
    Inventors: Hisashi Senga, Tomotada Kamei, Kenzo Ishibashi, Hideki Hayashi, Yohichi Saitoh
  • Patent number: 7463561
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: December 9, 2008
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Patent number: 7460448
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: April 23, 2007
    Date of Patent: December 2, 2008
    Assignee: Panasonic Corporation
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20080259750
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: October 31, 2007
    Publication date: October 23, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Patent number: 7406012
    Abstract: In order to make it possible to reproduce information recorded on an optical recording medium without causing deterioration in the information, a semiconductor laser driving device include a semiconductor laser, a photodetecting element for receiving a part of light emitted from the semiconductor laser and converting the part of light into an electric signal corresponding to a light amount; a laser driving circuit for inputting a driving signal into the semiconductor laser in such a manner that an average value of the electric signal coincides with a given target value, and a high-frequency superimposing control section for controlling an amplitude of the high-frequency signal. The high-frequency superimposing control section controls the amplitude in such a manner that a peak-to-average ratio that is a ratio of a peak value of the electric signal with respect to the average value of the electric signal does not increase above a given reference value.
    Type: Grant
    Filed: October 21, 2003
    Date of Patent: July 29, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Tomotada Kamei
  • Publication number: 20080089195
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 17, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20080084798
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: October 31, 2007
    Publication date: April 10, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20080068944
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: October 31, 2007
    Publication date: March 20, 2008
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20070195663
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tap. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: April 23, 2007
    Publication date: August 23, 2007
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Publication number: 20070195664
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Application
    Filed: April 23, 2007
    Publication date: August 23, 2007
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki
  • Patent number: 7254107
    Abstract: An optical head is provided with: an objective-lens-use opening that determines an aperture of the objective lens; a light-source light-quantity controlling opening that aperture-controls light that has been separated by the light separation device; a light detector that receives light that has been aperture-controlled by the light-source light-quantity controlling opening; and a light detector that receives light that has been reflected by the optical recording medium, and has an arrangement in which: the length of the optical light path from the spherical aberration correcting device to the objective-lens-use opening is made virtually the same as a length of the optical light path from the spherical aberration correcting device to the light-source light-quantity controlling opening, and the aperture of the light-source light-quantity controlling opening has virtually the same size as the aperture of the objective-lens-use opening.
    Type: Grant
    Filed: April 6, 2004
    Date of Patent: August 7, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hidenori Wada, Tomotada Kamei, Sadao Mizuno, Hideki Hayashi
  • Patent number: 7227819
    Abstract: An optical information apparatus of the present invention includes: an optical pick-up head including: a light source; a diffraction unit; a condensing unit; a beam splitter; a photodetector; and a tracking error signal generator. An optical recording medium has tracks arranged substantially at a constant pitch. An average of a pitch is tp. When a main beam is placed on the track, a first sub-beam and a second sub-beam are placed between the tracks.
    Type: Grant
    Filed: August 22, 2003
    Date of Patent: June 5, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shin-ichi Kadowaki, Kousei Sano, Akihiro Arai, Katsuhiko Yasuda, Tomotada Kamei, Hiroaki Yamamoto, Fumitomo Yamasaki