HIGH ACCURACY CYLINDRICAL MIRROR MEASUREMENT BY THREE-DIMENSIONAL NANO-PROFILER BASED ON THE NORMAL VECTOR TRACING METHOD

摘要

In this study, a result comparison between the nano-profiler and CGH interferometer was prepared with a same sample of cylindrical mirror, in order to evaluate the properties of new-developed non-contact three-dimensional nano-profiler based on normal vector tracing method. The figure errors were measured ten times, and the average value were obtained below 200 nm PV with sub-nanometer repeatability. The results of two methods were well agreed within the range of 50 nm PV or less and it shows that our newly developed nano-profiler is succeeded to measure a typical free-form optics of cylindrical mirror with same or higher uncertainty than that of common interferometry methods. Furthermore, the new nano-profiler is possible to improve the measurement uncertainty higher than A/10, because it does not require any reference optics for figure measurement, and is able to measure its systematic and motion errors independently by other methods.