实现可见光波段的远场超衍射极限聚焦和超分辨成像对科学研究和工程应用都具有重要意义。尽管近年来平面超透镜由于理论上的创新和便于集成等特点备受关注，但该类型超透镜的加工制备异常昂贵且耗时，目前全球仅有少数顶级实验室有制备能力。因此，探索研究一种较低成本且能快速被制备的超衍射透镜具有重大意义。在前期研究的基础上，本项目拟开发基于Pancharatnam–Berry相位和液晶的可调超衍射极限透镜，通过高精度的空间微畴光取向技术调制液晶指向矢，使其满足超衍射聚焦透镜的相位分布，从而实现快速廉价的制备液晶超透镜的方法。此外，拟通过设计相干条件，制备得到满足远场（f>200um）、数值孔径NA>0.9、焦斑尺寸FHWM<0.4λ的高效率（>80%）的可电调的液晶超透镜，并探索该类新型的液晶透镜在远场超分辨成像中的应用。该项目的研究对液晶光学透镜和纯光学的远场超分辨成像等方面具有重要意义。

Far-field super-focusing beyond diffraction limit and super-resolution imaging are of vital importance to both scientific research and industrial applications. Although the planar metalens has attracted extensive interests due to its novel design principle and capability of integration, the fabrication of the metalens such as metasurface lens is extremely expensive and time-consuming, which can only be done by limited labs with excellent fabrication facilities around the world. Hence, it is of great importance to develop metalens which can focus beyond the diffraction limit and can be fabricated by an efficient and cost-effective approach. Based on the previous studies on planar ultrathin lens and super-focusing, this project aims to design a novel planar tunable lens with super-focusing properties based on Pancharatnam-Berry phase and liquid crystal. High-accuracy photoalignment method with micron-sized resolution will be adopted to tune the directors of the liquid crystal according to the phase profile of the lens, thus leading to a fast and cost-effective roadmap to fabricate the planar metalens. Moreover, this work aims to design electrically-tunable liquid crystal metalens with focal length f>200um, NA>0.9, FWHM<0.4λ and efficiency >80% based on optimizing its spatially-variant phase profile. The application of this kind of metalens in far-field super-resolution imaging will be also investigated. This research will benefit the study of liquid crystal lens and far-field super-resolution imaging in the visible range.