Patents by Inventor Aoe Takashi

Aoe Takashi 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: 7126889
    Abstract: A circuit to improve the SN characteristic of a tracking error signal. This tracking error detection circuit is formed as a push-pull system utilizing a quadrant type photo-detector and provided with 4 gain control amplifiers 20, 22, 24, and 26, 4 bottom envelope circuits 28, 30, 32, and 34, a pair of subtracting circuits 36 and 38, adding (subtracting) circuit 40, offset circuit 42, and gain control circuit 44. Bottom envelope circuits 28, 30, 32, and 34 are configured with a capacitor-type peak-hold circuit, for example, whereby bottom envelopes of RF signals SA, SB, SC, and SD given from light receiving areas A, B, C, and D of a photo-detector via gain control amplifiers 20, 22, 24, and 26 are detected, and bottom envelope signals SAbtm, SBbtm, SCbtm, and SDbtm representing the waveforms of the respective bottom envelopes are output.
    Type: Grant
    Filed: December 9, 2002
    Date of Patent: October 24, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Koyu Yamanoi, Hironobu Murata, Aoe Takashi
  • Publication number: 20040047250
    Abstract: A circuit to improve the SN characteristic of a tracking error signal. This tracking error detection circuit is formed as a push-pull system utilizing a quadrant type photo-detector and provided with 4 gain control amplifiers 20, 22, 24, and 26, 4 bottom envelope circuits 28, 30, 32, and 34, a pair of subtracting circuits 36 and 38, adding (subtracting) circuit 40, offset circuit 42, and gain control circuit 44. Bottom envelope circuits 28, 30, 32, and 34 are configured with a capacitor-type peak-hold circuit, for example, whereby bottom envelopes of RF signals SA, SB, SC, and SD given from light receiving areas A, B, C, and D of a photo-detector via gain control amplifiers 20, 22, 24, and 26 are detected, and bottom envelope signals SAbtm, SBbtm, SCbtm, and SDbtm representing the waveforms of the respective bottom envelopes are output.
    Type: Application
    Filed: December 9, 2002
    Publication date: March 11, 2004
    Inventors: Koyu Yamanoi, Hironobu Murata, Aoe Takashi