Kenyon & Kenyon LLP
Position-measuring device
In a position-measuring device for recording the relative position of a scanning unit and a measuring graduation that is movable with respect to the latter in at least one measuring direction, the scanning unit includes a plurality of grating structures as well as at least one reflector element. The elements in the scanning unit are arranged such that the beams of rays diffracted by the measuring graduation pass through first grating structures in the scanning unit, subsequently impinge on the reflector element, from which there takes place a retroreflection in the direction of the measuring graduation, and the partial beams of rays then pass through second grating structures and then once again impinge upon the measuring graduation. The first and the second grating structures are arranged such that, upon the first and second passing through of the partial beams of rays, a defined lens effect on the partial beams of rays results.
Dr. Johannes Heidenhain GmbH
G G
G01D G01D
inventional inventional
Wolfgang
Holzapfel