Patents by Inventor Tooru Fujishima

Tooru Fujishima 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: 4669072
    Abstract: A control apparatus for controlling an optical video disk player capable of optical recording and reproduction of video and/or audio information on a recording medium by a light beam. The control apparatus comprises a tracking failure detection circuit detecting failure of the light beam to accurately track along a track formed on the recording medium, and a light beam control signal generator circuit reducing the energy of the light beam in response to the detection of the tracking failure by the tracking failure detection circuit, whereby recording of information on the recording medium is inhibited in the event of occurrence of a tracking error.
    Type: Grant
    Filed: October 5, 1983
    Date of Patent: May 26, 1987
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Miura, Chiharu Takayama, Tooru Fujishima, Masuo Oku, Tooru Kawashima, Yoshimichi Kudo
  • Patent number: 4630252
    Abstract: An optical disc player for optically recording the video information or audio information onto a recording medium or optically reproducing the recorded information. The disc player includes a search unit for searching an information track having no signals recorded thereon prior to additionally recording an information signal on the unrecorded track. The search unit has a level detection circuit for detecting the energy value of the light reflected by the recording medium or an RF signal detection circuit for detecting the RF signal component. When the reflected light energy exceeds a predetermined value or the RF signal component is not detected, the search unit regards the track as a track having no signals recorded thereon, the search operation for a track having no signals being terminated and information can be recorded of the track having no signals recorded thereon.
    Type: Grant
    Filed: December 23, 1983
    Date of Patent: December 16, 1986
    Assignee: Hitachi, Ltd.
    Inventors: Yoshio Miura, Tooru Fujishima, Masuo Oku, Yoshimichi Kudo, Chiharu Takayama, Tooru Kawashima
  • Patent number: 4422104
    Abstract: A time base error correcting apparatus for a video disk player including a pickup means picking up a video signal recorded on a video disk, a burst gate stage extracting a burst signal from the detected video signal, and a phase comparison stage comparing the phase of the extracted burst signal with that of an output signal from a reference frequency signal oscillator to provide an output signal indicative of the result of phase comparison which is used to control a system correcting an error of the time base of the chrominance loop and to control a pickup control unit controlling the relative positions of the information pickup means and the video disk. In the apparatus, a gate circuit is provided so as to inhibit application of the phase comparison output signal to the pickup control unit controlling the relative positions of the information pickup and the disk, during at least a period of time of about 200 .mu.sec to 300 .mu.
    Type: Grant
    Filed: April 23, 1981
    Date of Patent: December 20, 1983
    Assignee: Hitachi, Ltd.
    Inventor: Tooru Fujishima
  • Patent number: 4416002
    Abstract: A recording/reproduction system is disclosed in which main information in the form of high-frequency signal is recorded in time sequence along a multiplicity of tracks adjacent to each other. A discrimination signal is superimposed on the high-frequency signal in advance for recording and has a different occupied frequency band for each adjacent track, whereby discrimination of lead or lag in track arrangement is accomplished. The difference of the discrimination signal between tracks may take the form of phase difference with the same frequency or signals of different frequencies.
    Type: Grant
    Filed: March 29, 1982
    Date of Patent: November 15, 1983
    Assignee: Hitachi, Ltd.
    Inventors: Masanori Oguino, Tooru Fujishima, Jun Matsumoto
  • Patent number: 4403244
    Abstract: An apparatus suited for correcting a variation in the time base of a reproduced signal in a video disc player comprises a frequency converter circuit for converting the frequency of the reproduced signal, a first time base compensating (APC) system including an automatic phase control loop for varying the frequency of the reproduced signal by controlling the phase of a converting signal supplied to the frequency converter circuit in dependence on a phase difference between the reproduced signal and a reference signal, and a second time base compensating system including a variable delay element controlled in dependence on a phase difference between the reproduced signal and the reference signal. Variation in the time base remaining uncorrected in the first compensating system is compensated by the second compensating system including the variable delay element.
    Type: Grant
    Filed: February 5, 1981
    Date of Patent: September 6, 1983
    Assignee: Hitachi, Ltd.
    Inventor: Tooru Fujishima
  • Patent number: 4310911
    Abstract: For focus and tracking controls for a pickup of an optical-type video disc player, wobbles are simultaneously applied to focus and tracking adjustment mechanisms. The wobble for focus and the wobble for tracking are effected by two signals 90.degree. phase-shifted from each other. The respective informations representative of focus and tracking errors are separately detected in a synchronous detection manner using the same two signals to provide focus and tracking control signals.
    Type: Grant
    Filed: January 30, 1979
    Date of Patent: January 12, 1982
    Assignee: Hitachi, Ltd.
    Inventor: Tooru Fujishima
  • Patent number: 3949161
    Abstract: A video signal reproducing system comprising means for driving a web of recording medium such as a tape at a constant speed, a self-scanned linear photoelectronic image device disposed for scanning in a direction perpendicular to the traveling direction of the recording medium, a clock pulse generator for applying clock pulses to this image device, and a light source for illuminating the recording medium, whereby information optically recorded on the recording medium can be scanned in a two-dimensional fashion to reproduce a video signal such as a television signal.
    Type: Grant
    Filed: July 19, 1974
    Date of Patent: April 6, 1976
    Assignee: Hitachi, Ltd.
    Inventors: Tooru Fujishima, Naoto Nishimura, Kazuyoshi Kuwahara, Shinji Ozaki, Masahiko Fujita