Author Affiliations
Abstract
1 Electronic Information School, Wuhan University, Wuhan 430072, China
2 NOEIC, State Key Laboratory of Optical Communication Technologies and Networks, Wuhan Research Institute of Posts and Telecommunications, Wuhan 430074, China
3 Photonics Research Centre, Guilin University of Electronic Technology, Guilin 541004, China
4 Integrated Circuit Advanced Process Center, Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China
The design of a conventional zoom lens is always challenging because it requires not only sophisticated optical design strategy, but also complex and precise mechanical structures for system adjustment. Here, we propose a continuous-zoom lens consisting of two chiral geometric metasurfaces with dielectric nanobrick arrays sitting on a transparent substrate. The metalens can continuously vary the focal length by rotating either of the two metasurfaces around its optical axis without changing any other conditions. Due to the polarization dependence of the geometric metasurface, the positive and negative polarities are interchangeable in one identical metalens only by changing the handedness of the incident circularly polarized light, which can generate varying focal lengths ranging from ∞ to +∞ in principle.
160.3918 Metamaterials 160.4670 Optical materials Chinese Optics Letters
2019, 17(11): 111603
1 武汉大学 电子信息学院, 湖北 武汉 430072
2 武汉邮电科学研究院 光纤通信技术与网络国家重点实验室, 湖北 武汉 430074
提出一种基于电介质纳米砖阵列的扇出衍射光学元件的设计和实现方案, 其纳米砖的深宽比低至1.5。这种扇出衍射光学元件被一束波长为633 nm的入射光束照射时, 可以在远场中得到均匀的4×4点阵, 发散角为32°×32°, 且数值模拟与实验结果吻合良好。基于超表面材料的扇出衍射光学元件具有连续、精确的相位操纵能力和较高的偏振转换效率, 并且仅需一步光刻制造工艺, 可以广泛应用于工程光学的各种领域, 例如光学传感, 激光雷达, 激光加工等。
超表面材料 几何相位 扇出衍射光学元件 相位调控 metasurfaces geometric phase fan-out diffractive optical elements phase manipulation
