Method of obtaining a reference correction value for an index mark of an angular encoder

US9759583B2 · kind B2 · utility

Assignee

• FARO Technologies, Inc. · US

Inventors

• Alexander Kramer · Austin, US
• Martin Ossig · Tamm, DE
• Reinhard Becker · Wiesbaden, DE

Key dates

• Filing date: Apr 29, 2015
• Grant date: Sep 12, 2017
• Expiry date: Oct 8, 2035

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/3473
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method for finding a reference correction value of an angular encoder index mark is given. The angular encoder has a first read head, a second read head, and a patterned element that includes incremental marks and an index mark. In a first instance, the first read head detects the presence of the index mark and, in response, the second read head generates a first analog signal. In a second instance, the first read head detects the presence of the index mark and, in response, the second read head generates a second analog signal. A processor determines the reference correction value based at least in part on the first analog signal and the second analog signal.