Patents by Inventor Toshitaka Iwamoto

Toshitaka Iwamoto 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: 6738334
    Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the base plate.
    Type: Grant
    Filed: November 9, 2000
    Date of Patent: May 18, 2004
    Assignee: Fujitsu Limited
    Inventors: Hidenori Saitou, Toshitaka Iwamoto, Hirataka Ukai, Yasukiyo Kunimatsu, Shigeru Juman, Tomoo Sukagawa, Masateru Sasaki, Tatsutoshi Nagasaki, Masao Uchiyama
  • Patent number: 6411581
    Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the bass plate.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: June 25, 2002
    Assignee: Fujitsu Limited
    Inventors: Hidenori Saitou, Toshitaka Iwamoto, Hirataka Ukai, Yasukiyo Kunimatsu, Shigeru Juman, Tomoo Sukagawa, Masateru Sasaki, Tatsutoshi Nagasaki, Masao Uchiyama
  • Patent number: 6388972
    Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the base plate.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: May 14, 2002
    Assignee: Fujitsu Limited
    Inventors: Hidenori Saitou, Toshitaka Iwamoto, Hirataka Ukai, Yasukiyo Kunimatsu, Shigeru Juman, Tomoo Sukagawa, Masateru Sasaki, Tatsutoshi Nagasaki, Masao Uchiyama
  • Patent number: 6141309
    Abstract: A miniaturized optical disc memory is receivable in a slot, of about 17 mm height, normally accommodating a floppy disc drive. A base includes a base plate with integral, peripheral sidewalls and an internal lateral partition wall which define a cartridge receiving slot on the upper surface of the base plate. First and second support plates extend from the partition wall to the rear peripheral sidewall of the base and define respective, first and second upper mounting surfaces and lower first and second cavities respectively receiving an ejection motor and a fixed optical system, individual optical components being mounted and aligned on integral, precision machined blocks in the second cavity for transmitting a laser beam and receiving a reflected beam along a central, longitudinal optical axis beneath the base plate.
    Type: Grant
    Filed: July 9, 1996
    Date of Patent: October 31, 2000
    Assignee: Fujitsu Limited
    Inventors: Hidenori Saitou, Toshitaka Iwamoto, Hirataka Ukai, Yasukiyo Kunimatsu, Shigeru Juman
  • Patent number: 5142520
    Abstract: A system for obtaining an optimum focusing position in an optical disc system. An optical beam is impinged onto a track of an optical disc, and a reflection signal having information regarding an intensity of an optical beam reflected by an optical disc is obtained. A predetermined frequency component, the frequency component being generated by a modulation caused by an existence of a pit on a track of the optical disc in a reflecting signal, is extracted from the reflection signal. Then a focus position in which a maximum intensity of the extracted frequency component is obtained is searched by changing the focus position of the optical beam. Further, the above system is incorporated in a focus servo control system for maintaining an optimum focusing position in an optical disc system during reading and writing operations, to determine an optimum offset value which is to be adjusted to compensate an error arisen from a construction of the focus servo control system, during an offset adjusting operation.
    Type: Grant
    Filed: June 28, 1989
    Date of Patent: August 25, 1992
    Assignee: Fujitsu Limited
    Inventors: Shigenori Yanagi, Akira Minami, Masateru Sasaki, Shigeru Arai, Toshitaka Iwamoto, Hidenori Saitoh
  • Patent number: 5077719
    Abstract: An optical disk access system capable of varying the focus position of a beam spot illuminating the optical disk. The focus position of the beam spot is varied in accordance with a mode of operation of the optical disk system. The various focus positions are automatically selected by the optical disk access system by intentionally vibrating the beam spot in a radial direction of the optical disk and detecting the amount of light reflected from the optical disk while varying a signal that changes the focus position of the beam spot. The optical disk system automatically selects a value of the signal determining the focus position of the beam spot that corresponds to maximum values derived from the light reflected from the optical disk.
    Type: Grant
    Filed: August 24, 1988
    Date of Patent: December 31, 1991
    Assignee: Fujitsu Limited
    Inventors: Shigenori Yanagi, Masateru Sasaki, Akira Minami, Toshitaka Iwamoto, Shigeyoshi Tanaka
  • Patent number: 4782474
    Abstract: An optical storage apparatus for storing and reading information on an optical disk with an optical beam, including a tracking servo system having an objective lens, which is driven in a focusing direction F and a tracking direction T by a lens actuator, and a tilting mirror, which is rotated by a mirror actuator. The tracking servo system eliminates beam shift by controlling the lens actuator and the mirror actuator to position the lens and the mirror so that the laser beam always passes through a back focal point of the lens located on the opposite side of the lens from the optical disk. As a result, the laser beam proceeds from the lens to the disk along a path which is parallel with the optical axis of the lens and strikes the disk perpendicularly. Accordingly, the return path of the laser beam reflected by the surface of the disk coincides with the incident path of the laser beam, and no beam shaft is experienced.
    Type: Grant
    Filed: January 30, 1986
    Date of Patent: November 1, 1988
    Assignee: Fujitsu Limited
    Inventors: Shigeru Arai, Toshitaka Iwamoto