A hardware implementation for low-order wavefront sensing and control in exoplanet imaging

We describe a NASA Strategic Astrophysics Technology initiative. Our objective is the implementation and closed-loop demonstration of a new optical wavefront control element for the active correction of low-order wavefront errors associated with telescope line-of-sight jitter, thermal gradients, and alignment drift. In concert with a Lyot coronagraph and Zernike wavefront sensor in a laboratory vacuum environment, this hardware demonstrates the separation of active low-order and stable high-order wavefront control at high levels of contrast and provides experimental evidence that significant sources of error have been identified and effectively controlled or mitigated.