The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 08, 1990
Filed:
Feb. 18, 1988
Dr. Johannes Heidenhain GmbH, Traunreut, DE;
Abstract
Several photoelectric position measuring systems are described which utilize diffraction gratings to define the reference magnitude. Diffracted component beams are introduced by means of coupling-in gratings that have different grid constants from one another into optical waveguides to a coupler and there brought into interference. The interfering component beams are conducted from the outputs of the coupler via optical waveguides to detectors which transform them into electrical signals which are phase-shifted with respect to one another. Displacement of the diffraction grating is a measure for the position change to be measured of one machine component mounted for translation relative to another.