Dr. Johannes Heidenhain Gmbh

Johannes Heidenhain Gmbh

Ralph Joerger

Wolfgang Holzapfel

Markus Meissner

Bernhard Musch

Joerg Drescher

Thomas Kaelberer

Walter Huber

Erwin Spanner

Jörg Drescher

Michael Hermann

Thomas Kälberer

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

A device for position determination includes a light source and a planar measurement reflector movable along a measurement direction oriented perpendicular to the measurement reflector. A detector device is disposed such that a beam emitted by the light source strikes the detector device after impinging on the measurement reflector so that, in an event of a movement of the measurement reflector along the measurement direction, a signal results which is dependent on a position of the measurement reflector and from which a reference signal is generatable at a defined reference position. A deflection unit is disposed so as to deflect the beam such that the beam strikes the measurement reflector twice and therebetween passes through the deflection unit. The deflection unit is arranged so that a deviation in beam direction, resulting after the first reflection from a tilt of the measurement reflector, is compensated after the second reflection.

Device for position determination

A device for interferential distance measurement between two objects that are situated in a movable manner with respect to each other along at least one shifting direction includes at least one light source as well as at least one splitting element, which splits a beam of rays emitted by the light source at a splitting location into at least two partial beams that propagate onward at different angles. The device furthermore includes at least one deflecting element that effects a deflection of the incident partial beams in the direction of a merging location, where the split partial beams are superimposed in an interfering manner and the optical paths of the partial beams of rays between the splitting location and the merging location being arranged such that the traversed optical path lengths of the partial beams between the splitting location and the merging location are identical in the event of a change of distance between the two objects. Furthermore, at least one detector system is provided for detecting distance-dependent signals from the superimposed pair of interfering partial beams.

Device for interferential distance measurement

In an optical position measuring device for detecting the relative position of a first measuring standard and a second measuring standard, movable relative to each other along at least one measuring direction, at a splitting grating, a beam bundle emitted by a light source is split up into at least two partial beam bundles. When passing through scanning beam paths, the partial beam bundles undergo different polarization-optical effects. After the differently polarized partial beam bundles are recombined at a combination grating, a plurality of phase-displaced, displacement-dependent scanning signals is able to be generated from the resulting beam bundle. No polarization-optical components are arranged in the scanning beam paths of the partial beam bundles between the splitting and recombination. To generate the different polarization-optical effects on the partial beam bundles, a conically incident illumination beam bundle impinges upon the splitting grating, the incident illumination beam bundle extending in a plane perpendicular to the measuring direction at an angle other than 0&#xb0;, the plane of incidence being defined by the grating normal to the splitting grating and the direction of incidence of the illumination beam bundle. The scanning beam paths of the partial beam bundles are arranged in mirror symmetry with respect to the plane of incidence between the splitting and recombination.

Optical position measuring device

A device for interferential distance measurement that includes a measurement reflector having a surface and a light source emitting a beam parallel to the surface. The device includes a splitter element including a splitter grating that is disposed perpendicular to the surface, wherein the splitter grating receives the beam and splits the beam into a measurement beam and a reference beam, wherein the measurement beam acts at least twice upon the measurement reflector along a path of the measurement beam. The device including a combining element, at which the measurement beam and the reference beam enter into interferential superposition to form interfering measurement and reference beams. The device further includes a detector arrangement, by way of which a scanning signal pertaining to a distance between the measurement reflector and a component of said device in a measuring direction can be generated from the interfering measurement and reference beams.

Device for distance measurement

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

An interferometer includes a light source, beam splitter, measuring reflector, reference retroreflector, detector system, and two transparent plane plates. The beam splitter splits a first beam of rays, emitted by the light source, into at least one measuring beam and at least one reference beam, defining a first splitting plane. The measuring beam propagates in a measuring arm and the reference beam propagates in a reference arm until being recombined at a recombining location, which is oriented parallel to the first splitting plane. The measuring reflector is disposed in the measuring arm, and the reference retroreflector is disposed in the reference arm. The first and second transparent plane plates are disposed parallel to each other in the beam path between the light source and the detector system. The reference retroreflector is formed in the first plane plate and the beam splitter is disposed on the second plane plate.

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

An optical position-measuring device includes a scanning bar extending in a first or second direction, and a scale extending in the other direction. The scale is offset by a scanning distance from the scanning bar in a third direction perpendicular to the first and second directions. The device has a light source whose light penetrates the scanning bar at an intersection point of the scanning bar and scale to fall on the scale and arrive back at the scanning bar. At a detector, the light is split by diffraction into different partial beams at optically effective structures of the scanning bar and scale and combined again. A periodic signal is obtained in the detector in response to: a shift between the scanning bar and scale in the first direction due to interference of combined partial beams, and a change in the scanning distance between the scanning bar and scale.

Optical position-measuring device having two crossed scales

An interferometric distance measurement device that includes a light source that emits a beam of light and a scanning unit. The scanning unit includes a scanning plate having a splitter that splits the beam of light into a measurement beam and a reference beam, wherein the reference beam is propagated solely within the scanning plate before reaching interferential superposition with the measurement beam at a unification site. A reflector is provided, wherein the reflector is embodied such that the measurement beam striking the reflector undergoes retroreflection in a direction regardless of any possible relative tilting of the scanning unit and of the reflector downstream of the unification site. A detector arrangement is provided in which a distance signal relating to a distance between the scanning plate and the reflector is detectable from interference between the measurement beam and the reference beam.

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Traunstein, Germany

Ralph Joerger