Reconstruction methods for the phase-shifted Zernike wavefront sensor

Abstract

The Zernike wavefront sensor (ZWFS) stands out as one of the most sensitive optical systems for measuring the phase of an incoming wavefront, reaching photon efficiencies close to the fundamental limit. This quality, combined with the fact that it can easily measure phase discontinuities, has led to its widespread adoption in various wavefront control applications, both on the ground but also for future space-based instruments. Despite its advantages, the ZWFS faces a significant challenge due to its extremely limited dynamic range, making it particularly challenging for ground-based operations. To address this limitation, one approach is to use the ZWFS after a general adaptive optics (AO) system; however, even in this scenario, the dynamic range remains a concern. This paper investigates two optical configurations of the ZWFS: the conventional setup and its phase-shifted counterpart, which generates two distinct images of the telescope pupil. We assess the performance of various reconstruction techniques for both configurations, spanning from traditional linear reconstructors to gradient-descent-based methods. The evaluation encompasses simulations and experimental tests conducted on the Santa cruz Extreme Adaptive optics Lab (SEAL) bench at UCSC. Our findings demonstrate that certain innovative reconstruction techniques introduced in this study significantly enhance the dynamic range of the ZWFS, particularly when utilizing the phase-shifted version.

Authors 11

1. Vincent Chambouleyron

   University of California, Santa Cruz

   Affiliation as printed

   Univ. of California, Santa Cruz (United States)

2. Mahawa Cissé

   Centre National de la Recherche Scientifique · Aix-Marseille Université

   Affiliation as printed

   Aix Marseille Univ., CNRS, CNES, LAM (France)

3. Maïssa Salama

   University of California, Santa Cruz

   Affiliation as printed

   Univ. of California, Santa Cruz (United States)

4. Sebastiaan Y. Haffert Aachen Leiden Univ. (Netherlands)

   Leiden University · University of Arizona

   Affiliation as printed

   Leiden Univ. (Netherlands)

   The Univ. of Arizona (United States)

5. Vincent Déo
   Affiliation as printed

   Subaru Telescope, NAOJ (United States)

6. Charlotte Guthery

   W.M. Keck Observatory

   Affiliation as printed

   W.M. Keck Observatory (United States)

7. J. Kent Wallace

   California Institute of Technology

   Affiliation as printed

   California Institute of Technology (United States)

8. Daren R. Dillon

   University of California, Santa Cruz

   Affiliation as printed

   Univ. of California, Santa Cruz (United States)

9. Rebecca Jensen-Clem

   University of California, Santa Cruz

   Affiliation as printed

   Univ. of California, Santa Cruz (United States)

10. Philip M. Hinz

    University of California, Santa Cruz

    Affiliation as printed

    Univ. of California, Santa Cruz (United States)

11. Bruce Macintosh

    University of California, Santa Cruz

    Affiliation as printed

    Univ. of California, Santa Cruz (United States)