Implementation of straightness measurements at the Nanometer Comparator

Weichert, Christoph; Bosse, Harald; Flügge, Jens; Köning, Rainer; Köchert, Paul; Wiegmann, Axel; Kunzmann, H.

doi:10.1016/j.cirp.2016.04.070

Cited by 10 publications

(12 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High-accuracy instruments for the calibration of line scales and linear encoders are described elsewhere (e.g. [36], [285]). High-accuracy line scales made of low-expansion materials are used for comparing world-wide measurement capabilities [37].…”

Section: Line Scalesmentioning

confidence: 99%

Dimensional artefacts to achieve metrological traceability in advanced manufacturing

et al. 2020

View full text Add to dashboard Cite

Section: Line Scalesmentioning

confidence: 99%

Dimensional artefacts to achieve metrological traceability in advanced manufacturing

et al. 2020

View full text Add to dashboard Cite

“…It is equipped with a slide with a moving range of 600 mm. The horizontal straightness motion error of the slide is repeatable with a standard deviation in the range of 2 nm while moving in one direction, and differs in the range of ±10 nm between the moving directions [6]. Therefore, the reproducibility of the horizontal straightness motion error of the slide itself is not a sufficient reference to characterise the straightness interferometer in the single-digit nanometre range.…”

Section: Introductionmentioning

confidence: 99%

Investigation into the limitations of straightness interferometers using a multisensor-based error separation method

Weichert

Köchert

Schötka

et al. 2018

Meas. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

The uncertainty of a straightness interferometer is independent of the component used to introduce the divergence angle between the two probing beams, and is limited by three main error sources, which are linked to each other: their resolution, the influence of refractive index gradients and the topography of the straightness reflector. To identify the configuration with minimal uncertainties under laboratory conditions, a fully fibre-coupled heterodyne interferometer was successively equipped with three different wedge prisms, resulting in three different divergence angles (4°, 8° and 20°). To separate the error sources an independent reference with a smaller reproducibility is needed. Therefore, the straightness measurement capability of the Nanometer Comparator, based on a multisensor error separation method, was improved to provide measurements with a reproducibility of 0.2 nm. The comparison results revealed that the influence of the refractive index gradients of air did not increase with interspaces between the probing beams of more than 11.3 mm. Therefore, over a movement range of 220 mm, the lowest uncertainty was achieved with the largest divergence angle. The dominant uncertainty contribution arose from the mirror topography, which was additionally determined with a Fizeau interferometer. The measured topography agreed within ±1.3 nm with the systematic deviations revealed in the straightness comparison, resulting in an uncertainty contribution of 2.6 nm for the straightness interferometer.

show abstract

“…However, due to their low measurement throughput and limited measurement range, it is not a realistic way to measure the whole area of a VLS grating by those instruments. Vacuum interferometric comparators can also be employed for the evaluation of the pitch distribution of a VLS grating [27][28][29][30][31]. Especially, with the employment of a twodimensional (2D) comparator [32], a VLS planar scale grating is also expected to be evaluated.…”

Section: Introductionmentioning

confidence: 99%

Self-calibration of a variable-line-spacing grating for an absolute optical encoder with a Fizeau interferometer

Xiong¹,

Quan²,

Shimizu³

et al. 2021

Meas. Sci. Technol.

View full text Add to dashboard Cite

The principle of the self-calibration method for the evaluation of a planar scale grating having a constant pitch is extended to realize the evaluation of the pitch distribution of a planar scale grating having variable line spacings (VLSs) along the X- and Y-directions. In the conventional self-calibration method, the wavefronts in the zeroth-order diffracted beam and the first-order diffracted beams observed by a Fizeau interferometer arranged in the Littrow configuration were employed to evaluate the pitch deviation of a scale grating. The arithmetic operation with the wavefront data realizes the evaluation of the pitch deviation over a large area in a short time, while cancelling the influence of the out-of-flatness of a scale grating. Meanwhile, theoretical equations in the conventional self-calibration method cannot be directly applied to the evaluation of a VLS grating due to its unique properties of the pitch distribution. In this paper, major modifications are thus made to the conventional theoretical equations for deriving the pitch distribution of a VLS grating. To verify the performance of the newly proposed method, the pitch distribution of a VLS grating employed in a commercial planar absolute encoder is evaluated in experiments.

show abstract

Implementation of straightness measurements at the Nanometer Comparator

Cited by 10 publications

References 17 publications

Dimensional artefacts to achieve metrological traceability in advanced manufacturing

Dimensional artefacts to achieve metrological traceability in advanced manufacturing

Investigation into the limitations of straightness interferometers using a multisensor-based error separation method

Self-calibration of a variable-line-spacing grating for an absolute optical encoder with a Fizeau interferometer

Contact Info

Product

Resources

About