Dr. Johannes Heidenhain Gmbh

Christoph Lingk

Wolfgang Holzapfel

Johannes Trautner

Elmar Josef Mayer

Ulrich Benner

Daniel Frese

Gerhard Vogt

Thomas Schürmann

In an optical position-measuring device for acquiring the rotational angle between two objects that are rotationally moveable relative to each other, a grating measuring standard rotating about an axis of rotation is arranged as a reflection grating. Position information both about an azimuthal rotary movement about the axis of rotation and about a radial displacement of the grating measuring standard is able to be obtained. At least one detection unit is used for scanning the rotating grating measuring standard in order to determine the azimuthal rotational angle as well as a radial displacement of the grating measuring standard. The neutral pivot points of the scanning of the grating measuring standard for the determination of the rotational angle and the displacement are situated in the same plane, with this plane being situated in parallel with the grating measuring standard. The neutral pivot point denotes the particular location about which the grating measuring standard or the detection unit is able to be tilted without a position offset.

Optical position-measuring device

In a position-measuring device for determining the position of a first object with respect to a second object that is displaceable relative to the first object, a measuring standard is connected to the first object and includes at least one periodic scale grating, which is arranged as a transmission grating and has a first periodicity. A scanning unit is connected to the second object and includes at least one light source, at least one periodic scanning grating, which has a second periodicity, and a detector system, which includes detector regions that are sensitive to radiation and are periodically disposed at a third periodicity in a detection plane. The bundles of rays emitted by the light source first impinge upon the scale grating and then pass through the scanning grating. The interaction of the bundles of beams with the scale grating and the scanning grating produces a periodic fringe pattern having the third periodicity in the detection plane which, when scanned with the aid of the detector system, makes it possible to generate a plurality of incremental signals that are phase-shifted relative to one another. The scanning grating is arranged between at least one first and one second transparent, plate-shaped carrier element, and the space between the scanning grating and the detector regions is completely filled with a material that has a refractive index of n&#x3e;1.3. The clearance between the scale grating and the adjacent boundary surface of the first carrier element is in the range of 10 &#x3bc;m to 200 &#x3bc;m.

Position-measuring device

An optical position-measuring device for determining the position of a first object relative to a second object movable relative to the first object along a measurement direction includes a scale with a measuring graduation connected to the first object and extending along the measurement direction. A scanner is connected to the second object and includes a fiber-optic array including optical fibers. The fiber-optic array is configured as a fiber-optic plate having an image-input face facing the scale and an image-output face facing the detector array. The fiber-optic array transmits a light pattern into a detection plane of the detector array. An interstitial medium is disposed between the image-output face of the fiber-optic plate and the detector array to ensure that an amount of deflection that the beams exiting the image-output face undergo on a path to the detector array is smaller than in a case without the interstitial medium.

An optical position-measuring device for absolute position determination includes a material measure extending along a measurement direction and including an incremental graduation and an absolute code. A scanning unit movable relative to the material measure has a light source, a scanning grating for optically scanning the incremental graduation and a detector device. The detector device includes an incremental detector for generating incremental signals from the optical scanning of the incremental graduation and an absolute detector for generating absolute signals from optical scanning of the absolute code. A common detection plane is located at a defined perpendicular distance from the scanning grating and/or a periodicity of a fringe pattern on the incremental detector is selected such that, in the event of scattering contamination in a region of the material measure and/or the scanning grating, amplitudes of the incremental signals and the absolute signals drop off equally.

Optical position-measuring device having incremental detector and absolute detector disposed in a common detection plane at a defined perpendicular distance from a scanning grating

An angle-measuring device having a scanning device with which scanning of a closed serial first code and scanning of a closed serial second code is enabled, wherein a length of the closed serial second code is less than a length of the closed serial first code, and the closed serial first code and the closed serial second code have at least one common code section. The angle-measuring device includes a detector array for generating first and second sequences of code words of a predetermined scanning length upon scanning of the closed serial first code and second codes, respectively. The first sequence includes a first partial sequence and one common partial sequence, and wherein the common partial sequence is created upon scanning of the common code section. The second sequence includes a second partial sequence and the common partial sequence. The angle-measuring device further includes a decoding device designed for decoding the first and second sequences of code words, wherein the closed serial first and second codes as well as the predetermined scanning length are selected such that code words of the first and second sequences have a Hamming distance greater than 1.

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Traunstein, Germany

Christoph Lingk