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Form and Wavefront Metrology

Working Group 4.21


Our working group develops and applies measurement technologies for optical systems for measurements with the smallest possible measurement uncertainty. We determine form measurement with quantities such as sphericity, wave aberration and the radius of sphere segments. We also determine other quantities – such as the homogeneity and refractive index of different types of glass or liquids, the wedge angle, the transmission of optical components that modify the form of beams, and the optical rotation of quartz control plates. To generate a traceability chain, it is also necessary to investigate the measurement accuracy of the modulation transfer function of lenses.
Working Group 4.22, Flatness Metrology, deals with the measurement of flat surfaces, whereas Working Group 4.24, Asphere Metrology, is responsible for the measurement of aspheres.

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  • Traceable Multi Sensor method (TMS) for form metrology of curved optical surfaces
  • Applications for mathematics-based measuring methods in close cooperation with PTB’s Working Group 8.42 which deals with Data Analysis and Measurement Uncertainty
  • Investigating the measurement accuracy of the modulation transfer function of lenses


In research projects, the working group cooperates with international partners from industry and universities along with research and metrology institutes.

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