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:
Nov. 18, 2014
Filed:
May. 15, 2012
Michael Hermann, Tacherting, DE;
Michael Hermann, Tacherting, DE;
Dr. Johannes Heidenhain GmbH, Traunreut, DE;
Abstract
An optical position-measuring device includes a measuring standard and a scanning unit. The measuring standard includes an incremental graduation and at least one reference marking at a reference position. The reference marking has two reference-marking subfields disposed in mirror symmetry relative to a reference-marking axis of symmetry, each of the subfields including a grating structure having a locally changeable graduation period. The scanning unit includes a divergently emitting light source, one or more gratings, and a reference-signal detector system. The reference-signal detector system has at least four detector arrays formed and positioned such that, from the scanning of the reference marking via the reference-signal detector system, first and second pairs of partial reference signals result, in each case having a signal pattern in phase opposition. The first pair of partial reference signals is offset by an offset amount relative to the second pair of partial reference signals.