High precision flatness over 300 mm

Project Description

This is a comparison of flatness measurements of an optical plane with openings of 300 mm diameter.
The participants have to measure the inner opening of 300 mm with optical instruments to avoid possible scratches on the surface when measuring with tactile instruments. The achievable measurement uncertainty of the flatness measurements should be less than 15 nm (k=2).

Subjects
Length (L)
Coordinator
Gerd Ehret, PTB (Germany)
Phone: +49 531 592-4220
E-Mail: gerd.ehret@ptb.de
Coordinating Institute
PTB (Germany)
Further Partners
National Institute of Metrology NIM (China)
National Metrology Institute of Japan NMIJ (Japan)
National Metrology Institute of South Africa NMISA (South Africa),
Russian Research Institute for Metrological Service VNIIMS (Russia)
European XFEL GmbH (Germany) informal participation