Patents by Inventor John Stanley Wirtz

John Stanley Wirtz 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).

  • Linear exposure control system
    Patent number: 4113378
    Abstract: A magnification signal of 64 - 100% is applied as an input parameter to a specially designed relaxation oscillator which produces a pulse train wherein the pulses thereof have a duration which vary in linear fashion with respect to the magnification input signal, the relaxation oscillator employing a constant current source in series relationship with an integrating capacitor which produces a saw tooth signal having a slope which is constant regardless of variations in the amplitude of the magnification input signal. The output pulses from the relaxation oscillator are counted to define an exposure control interval which changes linearly with respect to the input magnification signal.
    Type: Grant
    Filed: March 2, 1977
    Date of Patent: September 12, 1978
    Assignee: Itek Corporation
    Inventor: John Stanley Wirtz