Optical position-measuring device

US9410797B2 · kind B2 · utility

Assignee

• DR. JOHANNES HEIDENHAIN GMBH · DE

Inventors

• Wolfgang Holzapfel · Obing, DE
• Jörg Drescher · Samerberg, DE
• Robert Kellner · Munich, DE
• Markus Meissner · Teupitz, DE

Key dates

• Filing date: Oct 7, 2014
• Grant date: Aug 9, 2016
• Expiry date: Oct 7, 2034

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/38
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A position-measuring device for detecting the position of two objects movable relative to each other, includes a measuring standard that is joined to one of the two objects, as well as a scanning system for scanning the measuring standard, the scanning system being joined to the other of the two objects. The scanning system permits a simultaneous determination of position along a first lateral shift direction and along a vertical shift direction of the objects. To that end, on the part of the scanning system, two scanning beam paths are formed, in which a group of phase-shifted signals is able to be generated in each case at the output end from interfering partial beams of rays. In addition, via the scanning system, at least a third scanning beam path is formed, by which it is possible to determine position along a second lateral shift direction of the objects. The beam from a light source is able to be supplied to the scanning system via a first light guide and coupling-in optics in common for all three scanning beam paths. The interfering partial beams of rays produced in the three scanning beam paths are able to be coupled via common coupling-out optics, into a second light guid…