Liu Jianying, Chu Jinkui, Zhang Ran, Liu Rui, Fu Jiaxin
Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian, China.
Nanophotonics. 2023 Feb 24;12(6):1137-1146. doi: 10.1515/nanoph-2022-0712. eCollection 2023 Mar.
Wide field of view and polarization imaging capabilities are crucial for implementation of advanced imaging devices. However, there are still great challenges in the integration of such optical systems. Here, we report a bionic compound eye metasurface that can realize full Stokes polarization imaging in a wide field of view. The bionic compound eye metasurface consists of a bifocal metalens array in which every three bifocal metalenses form a subeye. The phase of the bifocal metalens is composed of gradient phase and hyperbolic phase. Numerical simulations show that the bifocal metalens can not only improve the focusing efficiency in the oblique light but also correct the aberration caused by the oblique incident light. And the field of view of the bionic compound eye metasurface can reach 120° × 120°. We fabricated a bionic compound eye metasurface which consists of three subeyes. Experiments show that the bionic compound eye metasurface can perform near diffraction-limited polarization focusing and imaging in a large field of view. The design method is generic and can be used to design metasurfaces with different materials and wavelengths. It has great potential in the field of robot polarization vision and polarization detection.
宽视场和偏振成像能力对于先进成像设备的实现至关重要。然而,此类光学系统的集成仍面临巨大挑战。在此,我们报道了一种仿生复眼超表面,它能够在宽视场中实现全斯托克斯偏振成像。该仿生复眼超表面由一个双焦金属透镜阵列组成,其中每三个双焦金属透镜构成一个子眼。双焦金属透镜的相位由梯度相位和双曲线相位组成。数值模拟表明,双焦金属透镜不仅可以提高斜入射光的聚焦效率,还能校正斜入射光引起的像差。并且,仿生复眼超表面的视场可达120°×120°。我们制作了一个由三个子眼组成的仿生复眼超表面。实验表明,该仿生复眼超表面能够在大视场中实现近衍射极限的偏振聚焦和成像。该设计方法具有通用性,可用于设计不同材料和波长的超表面。它在机器人偏振视觉和偏振检测领域具有巨大潜力。