Patents by Inventor David N. Reece

David N. Reece 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).

  • Focus tracking system
    Patent number: 4626103
    Abstract: A method and apparatus are disclosed for tracking the position of surfaces during certain processing such as optical projection printing. Light from a line or point source is made incident on the surface at a small angle to produce interference fringes between the reflected light and a reference beam. Any movement of the surface causes a shifting of the fringe pattern which can be detected by appropriate means such as a slit or grating and photodiode combination.
    Type: Grant
    Filed: March 29, 1984
    Date of Patent: December 2, 1986
    Assignee: AT&T Bell Laboratories
    Inventors: Martin Feldman, David N. Reece, John S. Wagner