New website getting online, testing
    • 摘要: 设计了一种在远红外波段基于超表面全息的宽频带多焦点透镜。通过设计8个C型谐振环单元,当以线极化波垂直入射到该组单元上时,其透射的交叉极化波产生0到2π范围的相位突变,同时透过率保持不变。利用全波仿真验证了该组谐振单元对垂直入射线极化波的异常折射特性,并采用计算全息的方法获得了多焦点透镜上的相位分布,根据相位分布对所设计的天线单元进行排列,得到了方形的超表面多焦点透镜。对该透镜进行仿真,结果显示在中心频率28 THz、焦距108 μm处有良好的多点聚焦效果。

       

      Abstract: A broadband multi-focus lens based on metasurface holography in the far-infrared region is designed. By designing 8 C-shaped resonant rings, when linearly polarized light waves are incident normally to this set of resonators, cross-polarized component of transmitted light will form the phase shift from 0 to 2π, meanwhile the amplitude transmittance remains constant. Full-wave simulation was utilized to verify anomalous refraction properties when linearly polarized light waves irradiated this set of resonators vertically. The phase distribution of multi-focus lens was obtained by adopting the computer-generated hologram (CGH) method. According to arranged resonant rings based on the calculated phase distribution, a squared multi-focus lens based on metasurface was obtained. Simulation for the designed lens was conducted. Results show a good multi-focusing performance at the central frequency 28 THz in the focal length of 108 μm.