US 11,656,105 B2
Optical position-measuring device
Ulrich Benner, Trostberg (DE); Tarek Nutzinger, Vachendorf (DE); Daniel Krempke, Teisendorf (DE); and Johannes Haunreiter, Burghausen (DE)
Assigned to DR. JOHANNES HEIDENHAIN GMBH, Traunreut (DE)
Filed by DR. JOHANNES HEIDENHAIN GmbH, Traunreut (DE)
Filed on Nov. 24, 2021, as Appl. No. 17/534,493.
Claims priority of application No. 10 2020 214 778.7 (DE), filed on Nov. 25, 2020.
Prior Publication US 2022/0163354 A1, May 26, 2022
Int. Cl. G01D 5/347 (2006.01); G01B 11/14 (2006.01); G01D 5/353 (2006.01)
CPC G01D 5/34723 (2013.01) [G01B 11/14 (2013.01); G01D 5/347 (2013.01); G01D 5/34784 (2013.01); G01D 5/3537 (2013.01)] 14 Claims
OG exemplary drawing
 
1. An optical position-measuring device for determining a position of a first object relative to a second object that is movable relative to the first object along at least one measurement direction, the optical position-measuring device comprising:
a scale connected to the first object and extending along the measurement direction, the scale comprising:
a first track having an incremental measuring graduation including graduation regions having different optical properties, the graduation regions of the incremental measuring graduation being arranged alternately periodically and the incremental measuring graduation having a measuring graduation periodicity along the measurement direction, wherein the measuring graduation periodicity indicates a sum of widths of adjacent, different graduation regions, and
a second track having an absolute measuring graduation including graduation regions having different optical properties, the absolute measuring graduation having a code for absolute position determination and the graduation regions of the absolute measuring graduation being arranged aperiodically along the measurement direction; and
a scanning unit connected to the second object, the scanning unit comprising:
at least one light source,
a detector having an absolute detector arrangement configured to detect an aperiodic light pattern transmitted from the absolute measuring graduation onto a detection plane and an incremental detector arrangement configured to detect a periodic light pattern transmitted from the incremental measuring graduation onto a detection plane, and
a fiber-optic plate having a plurality of optical fibers arranged adjacent to one another, the fiber-optic plate having an image entry area which faces the scale and an image exit area which faces the detector, the fiber-optic plate being arranged as a continuous component in front of the absolute detector arrangement and the incremental detector arrangement, wherein both absolute track information and incremental track information in the respective detection planes are transmitted via the fiber-optic plate in this manner.