The complete acquisition of the topography of a special multi-mirror arrangement with the help of a Fizeau interferometer

摘要

The interferometric length measurement value in multi-axis positioning and measuring systems is directly influenced by the topography of reference mirrors. Form deviations of the mirror plane can cause systematic measurement errors because the specimen geometry is superimposed upon the topography of reference mirrors. This article discusses the complete acquisition of the topography of a special mirror arrangement with the help of a Fizeau interferometer to correct systematic measurement errors after the raw measurement using the expanded three-flat test. Furthermore, other influencing factors arc presented in the article, e.g., measurement errors caused by the Fizeau interferometer. Additionally, temporal changes of the reference mirror topography are detected by regularly occurring measurements, and the topography data used as the correction reference are updated accordingly.