title: Optimal energy-splitting method for an open-loop liquid crystal adaptive optics system.
abstract: A waveband-splitting method is proposed for open-loop liquid crystal adaptive optics systems (LC AOSs). The proposed method extends the working waveband, splits energy flexibly, and improves detection capability. Simulated analysis is performed for a waveband in the range of 350 nm to 950 nm. The results show that the optimal energy split is 7:3 for the wavefront sensor (WFS) and for the imaging camera with the waveband split into 350 nm to 700 nm and 700 nm to 950 nm, respectively. A validation experiment is conducted by measuring the signal-to-noise ratio (SNR) of the WFS and the imaging camera. The results indicate that for the waveband-splitting method, the SNR of WFS is approximately equal to that of the imaging camera with a variation in the intensity. On the other hand, the SNR of the WFS is significantly different from that of the imaging camera for the polarized beam splitter energy splitting scheme. Therefore, the waveband-splitting method is more suitable for an open-loop LC AOS. An adaptive correction experiment is also performed on a 1.2-meter telescope. A star with a visual magnitude of 4.45 is observed and corrected and an angular resolution ability of 0.31″ is achieved. A double star with a combined visual magnitude of 4.3 is observed as well, and its two components are resolved after correction. The results indicate that the proposed method can significantly improve the detection capability of an open-loop LC AOS.
authors.affiliation: State Key Laboratory of Applied Optics, Changchun Institute of Optics, Fine Mechanics, and Physics, Chinese Academy of Sciences, Changchun, Jilin 130033 China.
authors.forename: Zhaoliang
authors.initials: Z
authors.lastname: Cao
authors.forename: Quanquan
authors.initials: Q
authors.lastname: Mu
authors.forename: Lifa
authors.initials: L
authors.lastname: Hu
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Liu
authors.forename: Zenghui
authors.initials: Z
authors.lastname: Peng
authors.forename: Qingyun
authors.initials: Q
authors.lastname: Yang
authors.forename: Haoran
authors.initials: H
authors.lastname: Meng
authors.forename: Lishuang
authors.initials: L
authors.lastname: Yao
authors.forename: Li
authors.initials: L
authors.lastname: Xuan
mesh_terms: D017076:Computer-Aided Design; D004735:Energy Transfer; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005246:Feedback; D007909:Lenses; D050866:Liquid Crystals / Q000737:chemistry*; D012031:Refractometry / Q000295:instrumentation*