Patents by Inventor James Stephen Epstein

James Stephen Epstein 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).

  • Surveying instrument and method
    Patent number: 4113381
    Abstract: A tacheometer utilizes a gallium arsenide laser diode in a phase shifting distance encoder, a sinusoidal interpolator in a phase shifting shaft angle encoder, a mercury pool in a phase shifting two axis off-level encoder, a shared phase to digital decoder and a digital processor, to measure angles and distances corrected for off-level, speed of light variations, refraction and the earth's curvature.
    Type: Grant
    Filed: November 18, 1976
    Date of Patent: September 12, 1978
    Assignee: Hewlett-Packard Company
    Inventor: James Stephen Epstein