基于大Δn液晶材料的短焦距透镜阵列  

Short focal length lens array based on liquid crystal material with largeΔn

作　　者：李睿[1] 王琼华 LI Rui;WANG Qiong-hua(School of Electronics and Information Engineering, Sichuan University, Chengdu 610065, China;School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China)

机构地区：[1]四川大学电子信息学院,四川成都610065 [2]北京航空航天大学仪器科学与光电工程学院,北京100191

出　　处：《液晶与显示》2021年第4期509-515,共7页Chinese Journal of Liquid Crystals and Displays

基　　金：国家自然科学基金(No.61927809)。

摘　　要：为了在不改变液晶透镜孔径的基础上减小其焦距,本文提出了一种基于大Δn液晶材料的短焦距透镜阵列。该透镜阵列采用大Δn液晶材料,使其在低驱动电压下便可以积累较大的光程差。下基板采用ITO驱动电极与ITO接地电极交替排列的结构,且ITO驱动电极位于介电层上方。ITO接地电极使其边缘区域内存在弱电场,介电层平滑了液晶层内的电场。该设计不仅在大孔径范围内实现抛物线形的相位分布,且减小了驱动电压。仿真结果表明,当驱动电压为6 V时,该液晶透镜阵列的相位分布曲线与理想抛物线匹配较好。单个液晶透镜中心与边缘的相位差为42.17π左右,使其达到最小焦距约1.72 mm。当驱动电压从0 V增加到6 V时,液晶透镜阵列的焦距从∞减小到1.72 mm左右。因此,该液晶透镜阵列可以应用于2D/3D可切换显示、AR显示等领域。In order to reduce the focal length of liquid crystal lens without changing the aperture,a short focal length lens array based on liquid crystal material with largeΔn is proposed.The liquid crystal layer accumulates large optical path difference under low driving voltage because of the use of the liquid crystal material with largeΔn.The bottom substrate adopts the structure of alternating ITO driving electrode and ITO grounding electrode,and the ITO driving electrode is located above the dielectric layer.The ITO grounding electrode causes a weak electric field in its edges,the dielectric layer smooths the electric field in the liquid crystal layer.This design not only realizes the parabolic phase distribution in the large aperture range,but also reduces the driving voltage.The simulation results show that when the driving voltage is 6 V,the phase distribution of the liquid crystal lens array matches well with the ideal parabola.The phase difference between the center and edge of individual liquid crystal lens is approximately 42.17π,which results in a minimum focal length of about 1.72 mm.With the driving voltage increasing from 0 V to 6 V,the focal length of the liquid crystal lens array decreases from∞to about 1.72 mm.Therefore,the proposed liquid crystal lens array can be used in many application areas,such as 2D/3D switchable display,and AR display.

关 键 词：大Δn 液晶透镜阵列 短焦距 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] O753.2[自动化与计算机技术—计算机科学与技术]