Patents by Inventor Yvonne A. Boersma

Yvonne A. Boersma 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).

  • Information reading system and record carrier and reading device for use in such a system
    Patent number: 5255263
    Abstract: The disclosed information reading system comprises a record carrier (1) having at least two parallel tracks (2a, 2b) whose mutual distance is so small that the radiation beam (10) is modulated by the information patterns of the two tracks (2a, 2b) when the tracks are scanned by a focused radiation beam (10) along a line (18) indicating the center between the tracks (2a, 2b). The tracks comprise elementary areas, with the positions of the boundaries (80) of the elementary areas of the two tracks, viewed in the track direction, corresponding to each other. The information patterns in the tracks comprise elementary areas occupied by a mark and unoccupied elementary areas. The occupied elementary areas have a different influence on the radiation than the unoccupied elementary areas. When the two tracks (2a, 2b) are scanned, the center (17) of the scanning spot (14) is directed onto a line (18) which is located centrally between the tracks (2a, 2b).
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: October 19, 1993
    Assignee: U.S. Philips Corporation
    Inventors: Cornelis M. J. Van Uijen, Yvonne A. Boersma, James H. Coombs