Cell thickness dependence of electrically tunable infrared reflectors based on polymer stabilized cholesteric liquid crystals  

厚度依赖的聚合物稳定胆甾相液晶的电控红外反射器件（英文）

作　　者：Xiaowen Hu Laurens T. de Haan Hitesh Khandelwal Albertus P.H.J. Schenning Li Nian Guofu Zhou 胡小文;Laurens T.de Haan;Hitesh Khandelwal;Albertus P.H.J.Schenning;辇理;周国富(SCNU-TUE Joint Laboratory of Device Integrated Responsive Materials (DIRM), National Center for International Research on Green Optoelectronics, South China Normal University;Institute of Electronic Paper Displays and Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University;Shenzhen Guohua Optoelectronics Tech.Co.Ltd.;Laboratory of Functional Organic Materials & Devices, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology)

机构地区：[1]SCNU-TUE Joint Laboratory of Device Integrated Responsive Materials （DIRM）, National Center for International Research on Green Optoelectronics, South China Normal University, No 378, West Waihuan Road, Guangzhou Higher Education Mega Center, Guangzhou 510006, China [2]Laboratory of Functional Organic Materials ＆ Devices, Department of Chemical Engineering and Chemistry, Eindhoven University of Technology, P. O. Box 513, 5600 MB, Eindhoven, The Netherlands [3]Institute of Electronic Paper Displays and Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China [4]Shenzhen Guohua Optoelectronics Tech. Co. Ltd., Shenzhen 518110, China

出　　处：《Science China Materials》2018年第5期745-751,共7页中国科学（材料科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (51503070, 51561135014, U1501244);Guangdong Innovative Research Team Program (2013C102);Science and technology project of Guangdong Province (2015B090913004, 2016B090909001);Science and technology Project of Shenzhen (JSGG201704143009027);Guangdong Provincial Key Laboratory of Optical Information Materials and Technology (2017B030301007);the 111 Project

摘　　要：We reported here the fabrication of the elec- trically tunable infrared （IR） reflectors based on the polymer stabilized cholesteric liquid crystal （PSCLC） with negative dielectric anisotropy. A systematic study of the influence of cell gap on the electrically tunable reflection bandwidth was performed. When a direct current （DC） electric field was ap- plied, the reflection bandwidth red shifted in the cells with small cell gap, whereas the bandwidth broadening was ob- served in the cells with large cell gap. It is therefore reasonable to deduct that the reflection is dictated by the pitch gradient steepness which strongly relies on the cell thickness. The re- sults reveal that for making PSCLC based IR reflector windows with electrically induced bandwidth broadening, a minimal cell gap thickness is required. The resulted IR reflectors pos- sess a short native switching time and long-term operation stability, and are potentially applicable as smart energy saving windows in buildings and automobiles.本文报道了基于聚合物胆甾相液晶的、可电场调控的红外反射器件的制备,并系统研究了器件厚度对器件性能的影响.即施加直流电场后,厚度较小的器件的反射带宽仅发生红移;厚度较大的器件的反射带宽增宽.这种现象是由于不同厚度的胆甾相液晶薄膜中不同的螺距梯度导致的.本工作的研究结果表明在制备基于聚合物胆甾相液晶的电控红外反射器件时,厚度是决定反射性能的重要因素.由于该红外反射器件具有较快的响应时间和较好的工作稳定性,在建筑和汽车等的节能窗领域有较好的应用前景.

关 键 词：CHOLESTERIC cell gap polymer network electric reg-ulating infrared reflector 

分 类 号：O753.2[理学—晶体学]