High accuracy flatness metrology within the European Metrology Research Program

Recently, a project within the European Metrology Research Program (EMRP) started with the aim of improving the form metrology of optical surfaces. Within this project, in a work package on high accuracy flatness metrology, the National Metrology Institutes of the Czech Republic (CMI) and Germany (PTB) are involved. In the following, this EMRP project, the capabilities of CMI and PTB and the aims of the project will be presented. The new developments in flatness metrology cover the reduction of uncertainty, the enhancement of lateral resolution of deflectometric methods and the test of capacitive sensors for flatness metrology.