Patents by Inventor Akitoshi Tsunoka

Akitoshi Tsunoka 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).

  • Apparatus for recording and reproducing digital using dynamic range compression
    Patent number: 4825305
    Abstract: A digital signal recording and reproducing apparatus comprising a dynamic range compression/expansion apparatus. The compression/expansion apparatus receives a digital signal from, for example, an analog-to-digital converter and compresses the dynamic range of the digital signal and the so compressed digital signal is supplied to a recording signal processing circuit in the recording operation mode, while the apparatus receives a digital signal reproduction output from a recording/reproducing head and expands the dynamic range of the reproduced digital signal and the so expanded digital signal is supplied to, for example, a digital-to-analog converter in the reproducing operation mode.
    Type: Grant
    Filed: July 24, 1987
    Date of Patent: April 25, 1989
    Assignees: Hitachi, Ltd., Hitachi Video Engineering Incorp.
    Inventors: Shigeyuki Itoh, Yoshizumi Watatani, Akitoshi Tsunoka