A liquid crystal exposure apparatus that exposes a substrate with an illumination light via a projection optical system is equipped with: a substrate holder that holds the substrate; a substrate encoder system that includes head units and scales, and acquires the position information of the substrate holder on the basis of the output of the head units; and a drive section that relatively moves one of the head units and the scales on the substrate holder with respect to the other.

A method of compensating errors in a coordinate measuring machine adapted for determination of at least one spatial coordinate of a measurement point on an object to be measured. The method comprises measuring a distance from the first reference element to the first structural component, wherein the measured distance indicates a displacement or a deformation of the first structural component, defining a dynamic model with a first set of state variables, the state variables being related to a set of physical properties of the reference module and representing an actual state of the reference module, deriving the actual state of the reference module by a calculation based on the dynamic model, and deducing compensation parameters based on the actual state.

For providing an apparatus and method for providing a graphic representation (1) or a graphic representation sequence for detection by a detector (3) which provide a simple and effective variation of a graphic representation (1) or a graphic representation sequence for detection by the detector (3) an apparatus is claimed, comprising: a sequence of graphic representations (1) along an optical axis (2), an optical device (4) for focusing on at least one of the graphic representations (1), so that the at least one of the graphic representations (1) is visible by a detector (3) preferably with a predefinable sharpness, a control unit (5) for defining and providing a focusing sequence on the at least one of the graphic representations (1) by the optical device (4) for providing a change of visibility of the graphic representations (1) or of a part of the graphic representations (1) by the detector (3) in order to allow for the verification of the correct functioning of the detector.

A three-dimensional coordinate measurement apparatus capable of reducing shaking of a Y carriage and improving measurement accuracy. The Y carriage is supported by two strut members which are across a surface plate and movable in a Y-axis direction. The two strut members include a first strut member having a driving mechanism and a second strut member which moves following the first strut member. A guide portion parallel to the Y-axis direction is formed in the surface plate on a first strut member side. Side surface support members support the first strut member on the surface plate by holding both opposed side surfaces of the guide portion. The driving mechanism includes a roller having an axis perpendicular to a surface plate surface, and the roller is brought into contact with one side surface of the guide portion and rolled to move the Y carriage relatively to the surface plate.

In an exposure apparatus, on a substrate holder (34), a plurality of grating areas (RG) is arranged mutually apart in the X-axis direction, and a plurality of heads (66a to 66d) that irradiates a measurement beam with respect to the grating area and can move in the Y-axis direction is arranged outside of the substrate holder. A control system controls movement of the substrate holder in at least directions of three degrees of freedom within an XY plane, based on measurement information of at least three heads of the plurality of heads facing the grating area and measurement information of a measurement device that measures position information of the plurality of heads. The measurement beam of each of the plurality of heads, during the movement of substrate holder in the X-axis direction, moves off of one of the plurality of grating areas and switches to another adjacent grating area.

A position-measuring device for determining an absolute position includes a measuring scale and a scanning unit that is movable relative to the measuring scale along at least one measuring direction. To generate a scannable signal pattern, the measuring scale has a measuring graduation which includes a raster of stripe elements arranged along the measuring direction at a measuring-scale longitudinal period. For the encoding of an absolute position, the stripe elements have a periodic structure having a measuring-scale transverse period along a transverse direction that is oriented perpendicular to the measuring direction. For scanning the signal pattern, the scanning unit has a two-dimensional detector system having a plurality of detector elements, which includes multiple detector columns having a plurality of detector elements in each case. The detector columns are periodically arranged along the measuring direction and the detector elements are periodically arranged along the transverse direction, so that by scanning the signal pattern, at least three periodic partial incremental signals are able to be generated with regard to relative movements along the measuring direction, as well as at least one absolute-position signal per detector column.

A position detection encoder includes a scale that has a position detection pattern and a linear pattern that is formed in a direction parallel to a length direction of the position detection pattern; and a position detector generating a position detection signal with a different value due to a displacement of the position detection pattern in the length direction. In the position detector, a position confirmation pattern is formed that includes two markers arranged at an interval equal to or less than an offset tolerance value for a positional relationship of the position detector and the scale in a width direction of the position detection pattern.

An optical position measuring device for recording a relative position of two scales includes the scales. The longitudinal extents of the scales are oriented parallel to a first and second measuring direction. A horizontal plane of movement is spanned by these measuring directions. A light source is configured to emit an illumination beam that is split into at least two sub-beam bundles at the first scale. The sub-beam bundles subsequently impinge on the second scale, which is tilted about the direction of the longitudinal extent thereof relative to the horizontal plane of movement, and are back-reflected to impinge again on the first scale and are recombined there such that a resulting signal beam is subsequently propagated toward a detection unit, via which phase-shifted scanning signals are generatable with respect to a relative movement of the scales along a third perpendicular measuring direction and the first or second measuring direction.

The present invention provides a position detection apparatus that is provided with a scale and a detector and includes a processing unit configured to perform processing for setting a number of light receiving elements that are consecutive in a direction of relative movement and whose outputs are to be added for the light receiving elements so that, in a first resolution mode, a phase of a component of a fourth spatial frequency lower than a spatial frequency corresponding to a frequency offset amount is detected and, in a second resolution mode for which a resolution is lower than the first resolution mode, a phase of a component of a spatial frequency of an interference image of a second grating pattern is detected.

A position encoder includes a carrier adapted to move with respect to a first sensor and a second sensor of a position encoder. The carrier also includes encoding elements situated on the carrier to interact with the first sensor. A first limit indicator is situated at a first location on the carrier to interact with the second sensor at a first position of the carrier corresponding to a first limit of the position encoder, and a second limit indicator is situated at a second location on the carrier to interact with the second sensor at a second position of the carrier corresponding to a second limit of the position encoder.