Dr. Johannes Heidenhain Gmbh

Johannes Heidenhain Gmbh

Joerg Drescher

Markus Meissner

Wolfgang Holzapfel

Bernhard Musch

Ralph Joerger

Thomas Kaelberer

Peter Speckbacher

Erwin Spanner

Josef Weidmann

Wolfgang Pucher

Ulrich Bichlmeier

Kilian Bauer

Ralf Bihr

Bernhard Pletschacher

A method corrects errors in position-measuring devices having material measures which are scanned by at least one scanning unit. Correction values are obtained in a calibration performed prior to a measurement operation. The correction values from the calibration are compressed for the measurement operation. The correction values are kept available for a defined number of correction points on the material measure and used during the measurement operation to correct acquired position values.

Method for correcting errors in position-measuring devices

An X-Y table with a position-measuring device includes a table which is disposed on a support and is movable on the support so that altogether the table is positionable in a plane parallel to an underlying stationary base. Two groups of scanning heads are disposed on the support. For position measurement in two directions, a respective one of the scanning heads directs light through a respective transmissive scale attached along an edge of the table such that a respective reflective scale, which is stationary relative to a processing tool disposed above the table, reflects the light through the respective transmissive scale back to the respective scanning head. In a central position of the table, the two groups are in positional correspondence with the transmissive scales, and, in either of two edge positions of the table, only one of the two groups is in positional correspondence with the transmissive scales.

X-Y table with a position-measuring device

An interferential position-measuring device determines a position of an object which is disposed to be movable along a measurement direction. A light source is configured to emit a beam which is split into two sub-beams. One of the sub-beams impinges on an optical functional element on the object. The sub-beams are subsequently superimposed and interfered at a superposition location and a resulting signal beam propagates toward an evaluation unit configured to generate a position-dependent measurement signal from the resulting signal beam. A switching element is disposed in the signal path downstream of the superposition location and upstream of a signal-digitizing device. The switching element is configured to define a specific sampling point in time.

Interferential position-measuring device and method for operating an interferential position-measuring device

An optical position measuring instrument including a first scale having a first graduation, wherein the first scale is disposed movable in a first measuring direction, and at a first defined position in the first measuring direction, the first scale includes a spatially limited first marking that differs from the first graduation. The optical position measuring instrument further including a second scale having a second graduation, wherein the second scale is disposed movable in a second measuring direction, and at a second defined position, the second scale includes a second reference marking that is usable for generating at least one reference signal at a reference position of the second scale only if the first scale is located in the first defined position.

Optical position measuring instrument

A position-measuring device, as well as a system having such a position-measuring device, is used for determining the position of a first object relative to a second object, the first and the second object being movable relative to one another along at least two measuring directions. The position-measuring device has an optical unit that is linked to one of the two objects and includes at least one light source, a detector system, as well as further optical elements in a defined configuration. In addition, the position-measuring device includes a measuring standard-reflector unit, which is provided on the other object, and has at least two differently formed regions in one track that are optically scannable by the optical unit for position sensing. The different formation of the regions makes switching among the various measuring directions possible during position sensing, and positional signals can be generated by the optical unit relative to the relative movement of the two objects for each measuring direction.

Position-measuring device and system having such a position-measuring device

In position-measuring devices and a systems having a plurality of position-measuring devices for determining the position of an object in several spatial degrees of freedom, the plurality of optical position-measuring devices scan the object from a single probing direction, and the probing direction coincides with one of the two main axes of motion.

Position-measuring device and system having a plurality of position-measuring devices

An interferometer includes a light source and a beam splitter, via which the beam of rays emitted by the light source is split into a measurement beam and a reference beam. The measurement beam propagates in a measuring arm extending in a first direction between the beam splitter and a measuring reflector. The measuring reflector brings about an offset perpendicular to the direction of incidence between the measurement beam falling on it and the measurement beam reflected back by it. In a reference arm extending in a second direction, the reference beam propagates between the beam splitter and a reference reflector. In addition, the interferometer has a detector system, to which the superposed and recombined measurement beam and reference beam are able to be supplied, and via which a distance-dependent interference signal with respect to the position of the measuring reflector is able to be generated. The measuring reflector in each case includes at least one transmission grating as well as a reflector element.

Interferometer

In a system and a method for positioning a processing tool in relation to a workpiece, an object alignment mark and the workpiece are situated on a first object. In addition, a workpiece alignment mark is situated on the workpiece. The processing tool via which the object alignment mark is detectable is situated on a second object, which is disposed so as to be displaceable along at least one movement direction in relation to the first object. Furthermore, an alignment sensor is disposed thereon, with whose aid the object alignment mark and the workpiece alignment mark are detectable. In addition, a scannable measuring standard, which extends along the at least one movement direction, is disposed on the second object. At least two scanning units for scanning the measuring standard are situated on the first object in order to thereby determine the relative position between the first and the second object along the movement direction, the two scanning units having a defined offset.

System and method for positioning a processing tool in relation to a workpiece

A position-measuring device is used to detect the relative position of two machine components that are disposed in a manner allowing movement relative to each other at least along a first and a second main direction of motion in a displacement plane. The device includes at least one measuring standard, which is mounted on a first machine component. At least six scanning units are mounted on a second machine component, and are used for the optical scanning of the measuring standard in at least two measuring directions in the displacement plane. At least two scanning units are assigned to each measuring direction. The scanning units of each respective measuring direction in the displacement plane are disposed non-centrosymmetrically in relation to a center of the second machine component.

Position-measuring device

In a system for detecting the position of an object in relation to a reference system, the object is arranged so as to be movable in relation to the reference system along at least two orthogonal first and second main movement axes. To record the position of the object in relation to the reference system, a position measuring device includes at least two two-dimensional measuring standards situated along the first main movement axis, and four scanning units for an optical scanning of these measuring standards. In addition, at least four additional supplementary scanning units are provided, which are situated between the four scanning units along the first main movement axis.

System having a plurality of scanning units of a position measuring device

A scale is attached to a carrier by optically contacting. The optically contacting bonds are formed by raised surface regions of the scale set apart from each other. Additional measures, such as the provision of adhesive surfaces, provide a rigid and vibration-resistant joint.

Method for attaching a scale to a carrier, a scale, and carrier having a scale

A position-measuring system is for measuring the position of an object, movable in several degrees of freedom, relative to a stationary object. The position-measuring system includes at least one measuring graduation that is joined to one of the objects, as well as a plurality of scanning units which are joined to the other object and which generate raw position signals based on the optical scanning of the measuring graduation. Moreover, a multiplexer unit is provided, the raw position signals generated by the scanning units being supplied to the multiplexer unit, and from there, the raw position signals of the various scanning units being transmitted in time multiplex operation to a downstream sequential electronics, without converting the raw position signals into position values beforehand.

Position measuring system

A position-measuring device is for determining the position of two objects which are arranged displaceably with respect to each other in at least one measuring direction, and a method is for the operation of such a position-measuring device. The position-measuring device includes a measuring graduation as well as a scanning device having a light source and one or a plurality of optical and/or optoelectronic components for generating displacement-dependent position signals. A semiconductor laser having great coherence length is provided as the light source, which is operated pulsed in a single-mode operational-mode.

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Samerberg, Germany

Joerg Drescher