Abstract: An optical position-measuring device includes a scale and a scanning reticle, whose relative position is determinable in three linearly independent spatial directions using interfering light beams. A splitter grating is disposed on the scanning reticle and adapted to split light into sub-beams of different diffraction orders. An optical grating is disposed on the scale and adapted to further split the sub-beams and to recombine them after they have been reflected back from the scanning reticle. Grating fields configured as phase gratings are disposed on a side of the scanning reticle that faces the scale. The grating fields act as diffractive optics that influence the further split sub-beams. The grating fields have different step heights. An output grating is disposed on the scanning reticle and adapted to output, as interfering sub-beams, light that has been multiply reflected between the scale and the scanning reticle.

Abstract: An optical position-measuring device includes a scale and a scanning reticle, whose relative position is determinable in three linearly independent spatial directions using interfering light beams. A splitter grating is disposed on the scanning reticle and adapted to split light into sub-beams of different diffraction orders. An optical grating is disposed on the scale and adapted to further split the sub-beams and to recombine them after they have been reflected back from the scanning reticle. Grating fields configured as phase gratings are disposed on a side of the scanning reticle that faces the scale. The grating fields act as diffractive optics that influence the further split sub-beams. The grating fields have different step heights. An output grating is disposed on the scanning reticle and adapted to output, as interfering sub-beams, light that has been multiply reflected between the scale and the scanning reticle.

Abstract: A position-measuring device includes a first scale and a second scale, which are arranged end-to-end to extend across a measurement range, as well as a scanning unit having a light source configured to emit a light beam. The first scale includes a reflective phase grating having first periodic marks which diffract an incident light beam into a predetermined diffraction order with a first diffraction efficiency. The second scale includes a reflective phase grating having second periodic marks that differ in shape from the first periodic marks. A reflectivity of the phase grating of the second scale is reduced compared to a reflectivity of the phase grating of the first scale to such an extent that the phase grating of the second scale diffracts the incident light beam into the predetermined diffraction order with the first diffraction efficiency.

Abstract: A position-measuring device includes a first scale and a second scale, which are arranged end-to-end to extend across a measurement range, as well as a scanning unit having a light source configured to emit a light beam. The first scale includes a reflective phase grating having first periodic marks which diffract an incident light beam into a predetermined diffraction order with a first diffraction efficiency. The second scale includes a reflective phase grating having second periodic marks that differ in shape from the first periodic marks. A reflectivity of the phase grating of the second scale is reduced compared to a reflectivity of the phase grating of the first scale to such an extent that the phase grating of the second scale diffracts the incident light beam into the predetermined diffraction order with the first diffraction efficiency.