Fan Chun-Yuan, Chuang Tsung-Jung, Wu Kuo-Hao, Su Guo-Dung J
Opt Express. 2020 Mar 30;28(7):10609-10617. doi: 10.1364/OE.386563.
Focus-tunable lenses are indispensable to optical systems. This paper proposes an electrically modulated varifocal metalens combined with twisted nematic liquid crystals. In our design, a metalens is employed to focus on different points depending on the polarization state of incident light. We demonstrated that the varifocal metalens has a sub-millisecond response time. Furthermore, the numerical aperture of both the first and second focal points can be customized to achieve a wide range of 0.2-0.7. Moreover, the full width at half maximum approached the diffraction limit at multiple focal points. Because of the advantages of our proposed electrically modulated metalens, it has the potential for application in optical technology and biomedical science, both of which require high image quality and a rapid response time.
聚焦可调谐透镜对于光学系统来说是不可或缺的。本文提出了一种结合扭曲向列型液晶的电调制变焦超表面透镜。在我们的设计中，超表面透镜用于根据入射光的偏振态聚焦于不同的点。我们证明了变焦超表面透镜具有亚毫秒级的响应时间。此外，第一和第二焦点的数值孔径都可以定制，以实现0.2 - 0.7的宽范围。而且，在多个焦点处，半高宽接近衍射极限。由于我们提出的电调制超表面透镜的优点，它在光学技术和生物医学科学中具有应用潜力，这两个领域都需要高图像质量和快速响应时间。
