Patent ID: 7161139
Filing Date: 2007-01-09
Classification: G01D

Abstract:
1. A position-measuring device for generating periodic incremental signals and at least one reference-pulse signal, comprising: a scale including a track extending in a measuring direction, a periodic incremental graduation arranged in the track, the periodic incremental graduation including a specific incremental graduation period, the track including, in at least one defined reference position, a discontinuity with respect to an optical property to generate a reference-pulse signal; and a scanning unit, one of (a) the scale and (b) the scanning unit movable with respect to the other one of (a) the scale and (b) the scanning unit in the measuring direction over a specific measurement path, the scanning unit including a light source and a plurality of detector elements configured to photoelectrically scan the incremental graduation; wherein in a first section of the measurement path, the incremental graduation includes a first transverse substructure configured to deflect incident radiation into at least a first spatial direction, and in a second section of the measurement path, the incremental graduation includes a second transverse substructure configured to deflect incident radiation into at least a second spatial direction different from the first spatial direction, the discontinuity with respect to optical deflection action of the transverse substructures of the incremental graduation resulting in a junction region between the first section and the second section; and wherein the plurality of detector elements includes at least one reference-pulse detector element arranged on at least one side of the scanning unit in the spatial directions and arranged to receive partial reference-pulse signals, the partial reference-pulse signals processed to yield the reference-pulse signal.