Patents by Inventor Theodoor C. A. Hens

Theodoor C. A. Hens 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).

  • Color display tube having color selection structure with rough surface
    Patent number: 5633559
    Abstract: A color display tube comprising a color selection structure which is provided with a layer of getter material, the surface on which the layer of getter material being provided is rough. In this manner heat radiation is increased and doming of the color selection structure is reduced.
    Type: Grant
    Filed: February 25, 1992
    Date of Patent: May 27, 1997
    Assignee: U.S. Philips Corporation
    Inventors: Theodoor C. A. Hens, Johannes M. A. A. Compen, Maria C. Van Uden, Thomas D. M. Vrancken
  • Colour cathode ray tube having a screening cap
    Patent number: 5408158
    Abstract: A color cathode ray tube comprises a color selection electrode which is secured to a frame and a magnetic screening cap. The frame has two diaphragm portions one of which is located near the color selection electrode and the other is further removed from the color selection electrode. The distance between the electron beams deflected towards the outermost apertures of the color selection electrode and the further removed diaphragm is at least 1 cm. By virtue thereof, the negative influence of the frame on the screening effect of the magnetic screening cap is substantially reduced.
    Type: Grant
    Filed: October 27, 1993
    Date of Patent: April 18, 1995
    Assignee: U.S. Philips Corporation
    Inventors: Theodoor C. A. Hens, Jean Winters, Adrianus J. Van Mensvoort
  • Color display tube having a suspension means for a color selection electrode
    Patent number: 5256941
    Abstract: A color display tube is set forth comprising a color selection electrode which is suspended from supporting elements in the corners of the display window of the color display tube. The suspension elements used to suspend the color selection electrode from the supporting elements comprise a resilient element which encloses an angle .alpha. with the normal to the center of the display window. The angle .alpha. (in degrees) is defined by:.alpha.= 90-x/2- .delta.where x is the maximum deflection angle of the electrons in the color display tube, and6.5<.delta.<1.5.In the case of a 110.degree. tube, 28.5.degree.<.alpha.<33.5.degree. . By virtue thereof, the effect of overall doming is substantially equal to the effect of ambient doming, as a result of which the average picture quality is improved.
    Type: Grant
    Filed: May 29, 1991
    Date of Patent: October 26, 1993
    Assignee: U.S. Philips Corporation
    Inventors: Johannes H. N. Gijrath, Theodoor C. A. Hens
  • Color display tube including a color selection electrode with border
    Patent number: 4933595
    Abstract: A color electron beam display tube comprises a color selection electrode having a large plurality of apertures on a border, the border, having an interior portion which extends towards the display window and an exterior portion extending away from the display window, characterized in that substantially every point of the border is an element of an electron beam path.
    Type: Grant
    Filed: October 6, 1988
    Date of Patent: June 12, 1990
    Assignee: U.S. Philips Corporation
    Inventor: Theodoor C. A. Hens