Fuh Andy Ying-Guey, Wu Zong-Han, Cheng Ko-Ting, Liu Cheng-Kai, Chen Yuan-Di
Opt Express. 2013 Sep 23;21(19):21840-6. doi: 10.1364/OE.21.021840.
The direct optical switching of bistable cholesteric textures (i.e., planar and focal conic textures) in chiral azobenzene-doped liquid crystals (LCs) is demonstrated. Chiral azobenzene is a chiral dopant with optically tuned helical twisting power that results from the photo-isomerization between trans- and cis- isomers via exposure to UV or visible light. The pitch length of the material can be optically and repeatedly elongated and shortened. With regard to free energy, LCs tend to be stable at planar (focal conic) textures when pitch length is elongated (shortened) by exposure to UV (visible) light. Thus, direct optical switchable LC displays are investigated.
在手性偶氮苯掺杂液晶（LCs）中实现了双稳态胆甾相织构（即平面织构和焦锥织构）的直接光开关特性。手性偶氮苯是一种手性掺杂剂，具有通过紫外光或可见光照射下反式和顺式异构体之间的光异构化进行光学调节的螺旋扭曲能力。该材料的螺距长度可以通过光学手段反复拉长和缩短。从自由能的角度来看，当通过紫外光（可见光）照射使螺距长度拉长（缩短）时，液晶倾向于在平面（焦锥）织构下保持稳定。因此，对直接光开关液晶显示器进行了研究。
