| Zugriffsnummer | 36263 |
| Dokumenttyp | Zeitschriftenartikel |
| Peer Review | unbekannt |
| Sprache | Englisch |
| Titel | Aperture alignment in autocollimator-based deflectometric profilometers |
| Autor(in); Institution |
Geckeler, Ralf D.; 5.2, Dimensionelle Nanometrologie, PTB-Braunschweig
Artemiev, Nikolay A.; 5.2, Dimensionelle Nanometrologie, PTB-Braunschweig
Barber, S. K.; Lawrence Berkeley National Laboratory, Advanced Light Source, CA, USA
Just, Andreas; 5.2, Dimensionelle Nanometrologie, PTB-Braunschweig
Lacey, I.; Lawrence Berkeley National Laboratory, Advanced Light Source, CA, USA
Kranz, Oliver; 5.2, Dimensionelle Nanometrologie, PTB-Braunschweig
Smith, B. V.; Lawrence Berkeley National Laboratory, Engineering Division, Berkeley, CA, USA
Yashchuk, V. V.; Lawrence Berkeley National Laboratory, Advanced Light Source, Berkeley, CA, USA
|
| Quelle/Jahr | Review of Scientific Instruments: 87 (2016), 051906-1 - 051906-8 |
| ISSN | 0034-6748 (PRINT) ; 1089-7623 (ONLINE) |
| DOI | |
| Verlag | Melville, NY: AIP |
| Freie Schlagworte | Deflectometry ; profilometry ; x-ray optics ; synchrotron metrology ; autocollimator ; alignment ; calibration ; surface slope metrology |
| Zusammenfassung | During the last ten years, deflectometric profilometers have become indispensible tools for the precision form measurement of optical surfaces. They have proven to be especially suitable for characterizing beam-shaping optical surfaces for x-ray beamline applications at synchrotrons and Free Electron Lasers. Deflectometric profilometers use surface slope (angle) to assess topography and utilize commercial autocollimators for the contactless slope measurement. To this purpose, the autocollimator beam is deflected by a movable optical square (or pentaprism) towards the surface where a co-moving aperture limits and defines the beam footprint. In this paper, we focus on the precise and reproducible alignment of the aperture relative to the autocollimator’s optical axis. Its alignment needs to be maintained while it is scanned across the surface under test. The reproducibility of the autocollimator’s measuring conditions during calibration and during its use in the profilometer is of crucial importance to providing precise and traceable angle metrology. In the first part of the paper, we present the aperture alignment procedure developed at the Advanced Light Source, Lawrence Berkeley National Laboratory, USA, for use with their deflectometric profilometers. In the second part, we investigate the topic further by providing extensive ray tracing simulations and calibrations of a commercial autocollimator performed at the Physikalisch-Technische Bundesanstalt, Germany, for evaluating the effects of the positioning of the aperture on the autocollimator’s angle response. The investigations which we performed are crucial for reaching fundamental metrological limits in deflectometric profilometry. |
Zitierung
Geckeler, R. D., Artemiev, N. A., Barber, S. K., Just, A., Lacey, I., Kranz, O., Smith, B. V., & Yashchuk, V. V. (2016). Aperture alignment in autocollimator-based deflectometric profilometers. Review of Scientific Instruments, 87, 051906-1–051906-8. http://doi.org/10.1063/1.4950734