Round robin comparison study on the form measurement of optical freeform surfaces

0541106 - ÚFP 2021 RIV GB eng J - Journal Article
Fortmeier, I. - Schachtschneider, R. - Lédl, Vít - Matoušek, Ondřej - Siepmann, J. - Harsch, A. - Beisswanger, R. - Bitou, Y. - Kondo, Y. - Schulz, M. - Elster, C.
Round robin comparison study on the form measurement of optical freeform surfaces.
Journal of the European Optical Society: Rapid publications. Roč. 16, č. 1 (2020), č. článku 2. E-ISSN 1990-2573
Institutional support: RVO:61389021
Keywords : Freeform optical surfaces * Interlaboratory comparison * Metrology
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 1.528, year: 2020
Method of publishing: Open access
https://jeos.springeropen.com/track/pdf/10.1186/s41476-019-0124-1.pdf

A round robin comparison of freeform form measurements was carried out by the project partners and stakeholders of a European metrology research project. Altogether six measuring instruments were considered: five different (pointwise and areal) optical devices and one tactile device. Three optical freeform surfaces were used for the comparison measurements, where two specimens were measured by five instruments and one specimen by four instruments. In this paper, the evaluation methods and results of this round robin are presented for the three freeform surfaces made from a temperature-stable material, Super Invar ®. The freeforms had diameters of 40 mm, 50 mm and 100 mm and best-fit radii of 39.75 mm (convex), 40.9 mm (convex) and 423.5 mm (concave). For comparison, the bilateral pointwise differences between the available measurements were calculated. The root-mean-square values of these differences ranged from 15 nm to 110 nm (neglecting spherical contributions) and provided an insight into the status of typical freeform measurement capabilities for optical surfaces.
Permanent Link: http://hdl.handle.net/11104/0318691