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:
Jan. 06, 2009
Filed:
May. 07, 2007
Ulrich Benner, Trostberg, DE;
Ulrich Benner, Trostberg, DE;
Dr. Johannes Heidenhain GmbH, Traunreut, DE;
Abstract
In a position-measuring device for acquiring the relative position of a scanning unit and a reflection measuring graduation movable relative thereto in at least one measuring direction, the scanning unit includes a light source and a detector arrangement in a detection plane. In a first variant of the scanning unit, at least one optical reflector element is positioned in the scanning beam path which has an optical effect on the scanning beam path to the effect that the distance between a virtual light source and the reflection measuring graduation on one hand, and the distance between the reflection measuring graduation and the detector arrangement/detection plane on the other hand are identical. In a second variant, in the scanning unit at least one optical transmission element is disposed in the scanning beam path which has an optical effect on the scanning beam path to the effect that the distance between the light source and the reflection measuring graduation on one hand, and the distance between the reflection measuring graduation and a detector arrangement in a virtual detection plane on the other hand are identical.