文献类型：期刊文献

中文题名：高对比度低压驱动全息聚合物分散液晶光栅

英文题名：High contrast and low threshold holographic polymer dispersed liquid crystal grating

作者：李文萃[1,2];郑致刚[3];刘永刚[1];宋静[4];宣丽[1]

机构：[1]中国科学院长春光学精密机械与物理研究所应用光学国家重点实验室,吉林长春130033;[2]中国科学院研究生院,北京100039;[3]华东理工大学理学院,上海200237;[4]长春理工大学材料科学与工程学院,吉林长春130022

年份：2010

卷号：18

期号：7

起止页码：1504

中文期刊名：光学精密工程

外文期刊名：Optics and Precision Engineering

收录：CSTPCD;;EI(收录号：20103313164492);Scopus;北大核心:【北大核心2008】；CSCD:【CSCD2011_2012】；

基金：国家自然科学基金资助项目(No.60277033;No.50473040;No.19974046;No.59973020);吉林省科委基金资助项目(No.20020603)

语种：中文

中文关键词：全息聚合物分散液晶光栅;扭曲向列(TN)模式;阈值电压;对比度

外文关键词：Holographic Polymer Dispersed Liquid Crystal（HPDLC） grating; Twist Nematic（TN） mode; threshold voltage; contrast ratio

摘要：为了降低全息聚合物分散液晶光栅的驱动电压并提高其对比度,基于偏振原理设计了一种新型电调谐光栅。对传统的全息聚合物分散液晶(HPDLC)光栅进行了基板表面取向处理,加强液晶的均一排列程度,消除了液晶区域内的散射;然后,在光栅前面放置扭曲向列(TN)偏振调谐器,通过调节入射光的偏振方向,实现光栅内液晶折射率的变化,进而改变与聚合物折射率的差别,实现衍射强度的调谐。实验结果表明:光栅的阈值电压降低到了0.75～0.8V,对比度提高到了245:1,是传统HPDLC光栅的6～7倍,同时也大幅降低了散射损失且稳定性良好,可满足高端光学设备及显示产品方面的需求。
To reduce the threshold and to improve the contrast of the conventional Holographic Polymer Dispersed Liquid Crystal（HPDLC） grating,a new type electrically tunable grating based on a Twist Nematic （TN） cell was designed.Firstly,the substrates of conventional HPDLC grating were processed to get an uniform alignment of liquid crystal in the grating,which makes the liquid crystal field depend strongly on the polarization of incident light.Then,a TN polarization modulator was placed in front of the grating to adjust the incident light polarization to change the refractive index of the liquid crystal field.Consequently,by matching the refractive index of polymer with the alignment of liquid crystal,the electrical-optical properties of the grating could be controlled.The experimental results indicate that the threshold voltage of the new HPDLC grating is as low as 0.75-0.8 V and the contrast ratio reaches 245：1,which is 6-7 times of that of the conventional HPDLC grating.The HPDLC grating can work in a stable state for a long time.