Linearization of periodic phase response for liquid crystal modulator
Liquid crystal modulator(LCM) is now widely applied, especially in optical telecommunication networks. However, according to the electro-optic characteristic of liquid crystal, we will obtain nonlinear phase response when LCM is driven by the voltage varying with time linearly(v=kt+v0). And in practical application this nonlinear phase response will affect the modulation precision, communication modulation efficiency and so on. This paper presents a logarithm driving signal model to linearize the nonlinear phase response of LCM between 0 and π. When driven by a periodic signal whose voltage varies from 2.0 to 10.7V in the way of logarithm in every periods, the LCM’s phase response hops in the point of intersection of two voltage periods. Therefore, we advance another periodic logarithm driving signal, whose voltage ascends from 2.0 to 10.7V in first half periods and descends from 10.7 to 2.0V in the other half periods. Furthermore, We find that the degree of phase response linearization of LCM decreases with the frequency of driving signal increasing. This paper proposes mapping the nonlinear phase response to linear one to overcome this problem. The experimental results indicate that obtaining the linear phase response of liquid crystal between 0 and π with different-frequency driving signals is feasible.
liquid crystal modulator (LCM) driving frequency phase response linearization
Wenjian Jia Yubo Li Li Chen Minghua Wang Jianyi Yang
Dept.of Information Science and Electronic Engineering,Zhejiang Univ.,Hangzhou,China; Dept.of Optical Engineering ,Zhejiang Univ.,Hangzhou,China;
国际会议
2008亚太光通信会议(Asia-Pacific Optical Communications 2008)
杭州
英文
2008-10-26（万方平台首次上网日期，不代表论文的发表时间）