Abstract: A scanning unit for an optical position measuring device that includes a detector system that has a first reference pulse signal detector region disposed along a measuring direction and a second reference pulse signal detector region disposed along the measuring direction. The relative disposition of the reference pulse signal detector regions in the measuring direction is selected as a function of the structuring of a reference marking field on a scale for generating a reference pulse signal. An incremental signal detector region is disposed along the measuring direction and between the first and second reference pulse signal detector regions to generate at least one incremental signal.

Abstract: An optical position measuring instrument, by way of which, along with other position signals regarding the relative location of two objects movable relative to one another, additionally at least one reference pulse signal regarding a defined relative position of the two objects can be generated. This instrument includes a light source, and a reference pulse transmission structure disposed upstream of the light source, which structure has a first irregular distribution of regions with two different optical properties, the beam path being divergent between the light source (LQ) and the reference pulse transmission structure (S). In addition, a reference pulse scale structure is provided adjacent to the transmission structure; this scale structure has an irregular distribution of regions with two different optical properties.