Open AccessImproved bandwidth of open loop liquid crystal adaptive optics systems with a proportional-derivative controller
Author(s) -
Xingyun Zhang,
Zhaoliang Cao,
Chengliang Yang,
Zenghui Peng,
Quanquan Mu,
Xuan Li
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.011651
Subject(s) - optics , bandwidth (computing) , adaptive optics , open loop controller , physics , liquid crystal , computer science , closed loop , telecommunications , control engineering , engineering
Open loop liquid crystal adaptive optics (LC AO) has overcome the disadvantage of low energy efficiency after years of research, and its use is very promising in ground-based large aperture telescopes for visible band imaging. However, the low system bandwidth of open loop LC AO still limits its application. In order to solve this problem, we bring the concept of proportional-derivative control (which is widely used in closed loop systems) into open loop LC AO in this paper. Experiment results verified that the system -3 dB rejection bandwidth could improve from 75 Hz to 112 Hz when tip-tilt aberration is introduced, and the mean relative contrast ratio of imaging results could improve 80% when high-order aberrations are introduced. The proposed control method has significant meaning in promoting the application of open loop LC AO in ground-based large aperture telescopes for visible imaging.