Patents by Inventor Mario L. Thomas

Mario L. Thomas 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).

  • Method of manufacturing a cathode ray tube and device for carrying out this method
    Patent number: 4578661
    Abstract: A method of manufacturing a cathode ray tube in which magnetic poles are provided in or around the neck (4) of the envelope (1) and around the paths of the electron beams extending substantially parallel to the axis (8) of the tube, said poles generating a permanent multipole magnetic field to correct the occurring errors of convergence and color purity and frame defects of the color display tube, which magnetic poles are formed by magnetizing a configuration (17) of magnetizable material which is provided around the paths of the electron beams, which configuration is magnetized by energizing a multipole coil unit (15) by means of a combination of currents with which a static multipole magnetic field is generated and the magnetization is produced by means of a decaying alternating magnetic field which is generated by means of an alternating field coil (16) and which initially drives the magnetizable material on both sides of the hysteresis curve into saturation.
    Type: Grant
    Filed: January 7, 1985
    Date of Patent: March 25, 1986
    Assignee: U.S. Philips Corporation
    Inventors: Lambertus J. J. van Rijsewijk, Mario L. Thomas, Henricus J. J. C. Meijer, Ronald van der Wilk