D6.2 - Measuring sub nanoradian angles

Abstract

This paper describes the application of optical interferometry for high accuracy angle metrology to characterize the performance of Diamond Light Source's small angle generator NANGO that is used to support testing of x-ray optics. The optical interferometer offers a higher resolution and bandwidth than is achievable with commercially available autocollimators and was used to measure traceably nanoradian steps and sub nanoradian oscillations generated by NANGO.