Patents by Inventor Stephen F. Royka

Stephen F. Royka 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).

  • Xerographic method for making a responsive answer system
    Patent number: 3938993
    Abstract: Permanent, meaningful information is so associated with removable, confusing information, at least some of which is usually similar in character to said permanent, meaningful information, as to make it effectively impossible for an observer to discriminate between the two types of information even though both types of information in the association may be legible. Such a system is advantageously used in instructional systems and particularly in responsive answer formats.
    Type: Grant
    Filed: November 27, 1973
    Date of Patent: February 17, 1976
    Assignee: Xerox Corporation
    Inventors: Stephen F. Royka, Robert G. Martin