Interferometric testbed for sub-nanometer stabilization of environmental motions for testing of advanced space telescopes

In several future space telescope missions, high long-term relative stability between optics is required for testing on the ground, as well as achieving the sensitivity goal in flight. Typically, thermal and seismic drifts on the ground are on the order of 1 μm over few hours, orders of magnitude above the testing requirements. To suppress these environmental motions, we developed a control system that is composed of interferometric sensors and PZT-based actuator. The system provides a stable environment to allow ground testing of the mission requirements. Our results show that this kind of system can provide picometer level stability at long timescale and that it should have many applications.