Yu Dian, Lou Shaozhen, Ou Xiangnian, Yu Ping, Duan Huigao, Hu Yueqiang
National Research Center for High-Efficiency Grinding, College of Mechanical and Vehicle Engineering, Hunan University, Changsha, 410082, China.
Songshan Lake Materials Laboratory, Dongguan, 523808, China.
Sci Rep. 2024 Oct 9;14(1):23627. doi: 10.1038/s41598-024-72680-w.
Digital Micromirror Devices, extensively employed in projection displays offer rapid, polarization-independent beam steering. However, they are constrained by microelectromechanical system limitations, resulting in reduced resolution, limited beam steering angle and poor stability, which hinder further performance optimization. Liquid Crystal on Silicon technology, employing liquid crystal (LC) and silicon chip technology, with properties of high resolution, high contrast and good stability. Nevertheless, its polarization-dependent issues lead to complex system and low efficiency in device applications. This paper introduces a hybrid integration of metallic metasurface with nematic LC, facilitating a polarization-independent beam steering device capable of large-angle deflections. Employing principles of geometrical phase and plasmonic resonances, the metallic metasurface, coupled with an electronically controlled LC, allows for dynamic adjustment, achieving a maximum deflection of ± 27.1°. Additionally, the integration of an LC-infused dielectric grating for dynamic phase modulation and the metasurface for polarization conversion ensures uniform modulation effects across all polarizations within the device. We verify the device's large-angle beam deflection capability and polarization insensitivity effect in simulations and propose an optimization scheme to cope with the low efficiency of individual diffraction stages.
数字微镜器件广泛应用于投影显示器中，可实现快速、与偏振无关的光束转向。然而，它们受到微机电系统限制，导致分辨率降低、光束转向角度有限且稳定性差，这阻碍了进一步的性能优化。硅基液晶技术采用液晶（LC）和硅芯片技术，具有高分辨率、高对比度和良好稳定性的特性。然而，其与偏振相关的问题导致系统复杂且器件应用效率低下。本文介绍了一种金属超表面与向列型液晶的混合集成，促成了一种能够进行大角度偏转的与偏振无关的光束转向器件。利用几何相位和表面等离子体共振原理，金属超表面与电控液晶相结合，实现动态调节，最大偏转角度达到±27.1°。此外，集成用于动态相位调制的注入液晶的介质光栅和用于偏振转换的超表面，确保了器件内所有偏振态的均匀调制效果。我们在模拟中验证了该器件的大角度光束偏转能力和偏振不敏感效应，并提出了一种优化方案来应对各个衍射级效率低下的问题。
