Optical metasurfaces with an ultra-thin, planar structure can easily adjust the phase and polarization of light waves. Based on the principle of the resonant phase, a cubic nanopillar is designed to construct the polarization-insensitive metalens in the visible light range. By simulating the phase and transmission efficiency of a cubic nanopillar with a width of ${50}\sim{200}\;{\rm nm}$, the optimized height of the nanopillar is obtained. Metalenses with different numerical apertures are designed to obtain the sub-wavelength focusing effect. The focusing performance of the same metalens remains the same when the right-handed circular polarization light and the left-handed circular polarization light are incident, respectively, which proves that the designed structure is insensitive to circular polarization light. At the same time, the different off-axis focusing metalenses that can achieve flexible focusing in the desired spatial location are also designed and investigated. This research provides a reference to design polarization-insensitive photonic integrated components and flexible imaging metalenses.

中文翻译：

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具有不同数值孔径和离轴聚焦特性的对极化不敏感的介电金属镜

具有超薄平面结构的光学超表面可以轻松调整光波的相位和偏振。基于共振相原理，设计了立方纳米柱，以在可见光范围内构造对偏振不敏感的金属。通过模拟宽度为$ {50} \ sim {200} \; {\ rm nm} $的立方纳米柱的相位和传输效率，获得了纳米柱的最佳高度。设计具有不同数值孔径的Metalenses以获得亚波长聚焦效果。当右旋圆偏振光和左旋圆偏振光分别入射时，相同金属离子的聚焦性能保持相同，这证明了所设计的结构对圆偏振光不敏感。同时，还设计和研究了可以在所需空间位置实现灵活聚焦的不同离轴聚焦金属镜。该研究为设计偏振不敏感的光子集成组件和柔性成像金属传感器提供了参考。