An Adaptive Secondary Mirror demonstrator: Construction and Preliminary Evaluation

Adaptive optics combines technologies that enable the correction of the wavefront distortion caused by the earth‘s atmospheric turbulence in real time. Adaptive secondary mirror (ASM) systems have been proposed and are now being developed. ASMs have advantages over conventional AO systems in terms of throughput, polarisation and IR emissivity. Previously, we reported the design of an ASM demonstrator along with its predicted performance. This paper reports the construction techniques and the results from the preliminary static and dynamic testing of such a demonstrator. In particular assembly methods that preserve the optical quality of the mirror are presented along with experimentally measured mirror influence functions and closed loop tip/tilt performance.