Characterization of the phase-shifting Zernike wavefront sensor for telescope applications

The dynamic Zernike wavefront sensor (ZWFS) is a common-path phase-shifting interferometric wavefront sensor with some attractive properties including superior sensing of low spatial frequencies and noise rejection. The ZWFS will be integrated as an auxiliary wavefront sensor for the Mount Palomar adaptive optics system on the 200” Hale Telescope. It is also being considered as the sensor for phasing the segmented mirrors of the Cerro Chajnantor Atacama Telescope (CCAT), a 25-meter diameter submillimeter telescope. Here we extend our analysis of the sensor to include its sensitivity to random noise as compared with the more traditional Shack-Hartman sensor. We also explore the accuracy of the sensor to Fourier and Zernike wavefront modes. We describe this analysis, the application to Palomar and CCAT, and the sensor's relevance to future segmented space telescopes.