Patents by Inventor Frederik Johannes van Roessel

Frederik Johannes van Roessel 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).

  • Video switching circuit
    Patent number: 4104678
    Abstract: A circuit has two amplifiers each of which have different transfer functions. Means are shown for switching between them. The output signal can be a matrixed or non-matrixed color signal, or a gamma or non-gamma corrected signal. The amplifiers can be differential amplifiers.
    Type: Grant
    Filed: May 19, 1977
    Date of Patent: August 1, 1978
    Assignee: North American Philips Corporation
    Inventor: Frederik Johannes Van Roessel
  • Video processing circuit
    Patent number: 4032974
    Abstract: A video processing circuit features direct current coupled circuits. This reduces streaking errors and lowers the power dissipation required.
    Type: Grant
    Filed: October 20, 1975
    Date of Patent: June 28, 1977
    Assignee: North American Philips Corporation
    Inventor: Frederik Johannes Van Roessel
  • Straylight compensation circuit and blanking circuit for same
    Patent number: 4001502
    Abstract: A straylight compensation circuit which corrects for excessive dark current features a blanking circuit to ensure a stable black level without spikes and blanking noise. The video is integrated to provide a measure of the average picture level and is added to a reference level to compare with the blanking level in the original signal. The blanking circuit has a differential amplifier with diodes to ensure a correct and stable black level without noise or spikes.
    Type: Grant
    Filed: June 24, 1975
    Date of Patent: January 4, 1977
    Assignee: North American Philips Corporation
    Inventor: Frederik Johannes van Roessel