2021

Arezki, Yassir; Su, Rong; Heikkinen, Ville; Leprete, François; Posta, Pavel; Bitou, Youichi; Schober, Christian; Mehdi-Souzani, Charyar; Alzahrani, Bandar Abdulrahman Mohammed; Zhang, Xiangchao; Kondo, Yohan; Pruss, Christof; Ledl, Vit; Anwer, Nabil; Bouazizi, Mohamed Lamjed; Leach, Richard; Nouira, Hichem

The design of innovative reference aspheric and freeform optical elements was investi-gated with the aim of calibration and verification of ultra-high accurate measurement systems. The verification is dedicated to form error analysis of aspherical and freeform optical surfaces based on minimum zone fitting. Two thermo-invariant material measures were designed, manufactured using a magnetorheological finishing process and selected for the evaluation of a number of ultra-high-precision measurement machines. All collected data sets were analysed using the implemented robust reference minimum zone (Hybrid Trust Region) fitting algorithm to extract the val-ues of form error. Agreement among the results of several partners was observed, which demon-strates the establishment of a traceable reference full metrology chain for aspherical and freeform optical surfaces with small amplitudes.