Determination of form/topography of high-quality flats

Project Description

Establish a comparison of flatness standards for form/topography measuring instruments. This comparison will be the first one dealing with high-quality determination of form/topography of high-quality flats.

Final Report

Results published in an open access paper: Metrologia 54 (2017) 85–93 "Intercomparison of flatness measurements of an optical flat at apertures of up to 150 mm in diameter".

Further Information

A high-quality flat artefact with a diameter of 330 mm, working diameter 300 mm, thickness of 70 mm, Zerodur, no coating, flatness RMS l/80 will be provided by the pilot laboratory.

Length (L)
Coordinating Institute
PTB (Germany)
Further Partners
National Metrology Institute of South Africa (ZA)
National Institute of Metrology (CN)