Vigan Arthur, Dohlen Kjetil, Mazzanti Silvio
Laboratoire d’Astrophysique de Marseille, UMR 6110, CNRS, Université de Provence, 38 rue Frédéric Joliot-Curie, 13388 Marseille Cedex 13, France.
Appl Opt. 2011 Jun 10;50(17):2708-18. doi: 10.1364/AO.50.002708.
Future extremely large telescopes will adopt segmented primary mirrors with several hundreds of segments. Cophasing of the segments together is essential to reach high wavefront quality. The phasing sensor must be able to maintain very high phasing accuracy during the observations, while being able to phase segments dephased by several micrometers. The Zernike phase contrast sensor has been demonstrated on-sky at the Very Large Telescope. We present the multiwavelength scheme that has been implemented to extend the capture range from ±λ/2 on the wavefront to many micrometers, demonstrating that it is successful at phasing mirrors with piston errors up to ±4.0 μm on the wavefront. We discuss the results at different levels and conclude with a phasing strategy for a future extremely large telescope.
未来的超大型望远镜将采用由数百个镜段组成的分段主镜。镜段的共相化对于实现高波前质量至关重要。相位传感器必须能够在观测期间保持非常高的相位精度，同时能够对失相达几微米的镜段进行相位调整。泽尼克相衬传感器已在甚大望远镜上进行了实地演示。我们展示了已实施的多波长方案，该方案将捕获范围从波前上的±λ/2扩展到许多微米，表明它在对波前上活塞误差高达±4.0μm的镜子进行相位调整方面取得了成功。我们在不同层面讨论了结果，并以未来超大型望远镜的相位调整策略作为总结。
