• Media type: E-Article
  • Title: Measuring the cophasing state of a segmented mirror with a wavelength sweep and a Zernike phase contrast sensor
  • Contributor: Cheffot, Anne-Laure; Vigan, Arthur; Leveque, Samuel; Hugot, Emmanuel
  • Published: Optica Publishing Group, 2020
  • Published in: Optics Express, 28 (2020) 9, Seite 12566
  • Language: English
  • DOI: 10.1364/oe.390576
  • ISSN: 1094-4087
  • Origination:
  • Footnote:
  • Description: The demand for higher resolution telescopes leads to segmented primary mirrors that need to be phased for operation. A phasing sensor applying a wavelength sweep technique provides a large capture range without modulating the position of individual mirror segments. This technique offers the potential to monitor the phasing state of a segmented telescope in parallel to the science observations. We evaluate the performance of the wavelength sweep technique using a Zernike phase contrast sensor for coarse phasing. Test results on a dedicated bench show 112 nm rms precision. With the help of a simulation, we explain a known error of the method and we suggest ways for improvements.
  • Access State: Open Access