Patent ID: 6907372

Claim:
A device for position indication and the detection of guidance errors, comprising: a scale comprising: a position measuring graduation arranged in a position measurement direction; a first guidance error measuring graduation which is arranged perpendicularly with respect to the position measurement graduation; a second guidance error measuring graduation which is arranged perpendicularly with respect to the position measurement graduation, wherein the first guidance error measuring graduation and the second guidance error measuring graduation are arranged on both sides of and adjacent to the position measuring graduation, wherein the first guidance error measuring graduation and the second guidance error measuring graduation each has a graduation period identical to the position measuring graduation and extend over an entire measurement distance; a position indication scanning unit movable with respect to the scale, wherein the position indication scanning unit scans the position measuring graduation for generating position measurement signals; and a guidance error scanning unit that is movable with respect to the scale, wherein the guidance error scanning unit scans the first guidance error measuring graduation for generating guidance error measurement signals.