| 摘要: | 隨著電子產品對輕薄化設計的需求日益增加，手機機型也呈現出越來越薄的發展趨勢。然而，目前手機普遍採用的傳統透鏡系統，由於需要多片透鏡組合以進行影像調整，導致整體機身尺寸難以進一步縮小。近年來，超穎透鏡的問世為此問題提供了全新的解決方案。超穎透鏡憑藉其輕薄特性，僅需單片即可實現相當於傳統多片透鏡組的光學功能，例如消色差、大視場角等等，超穎透鏡也逐漸成為許多電子產品替代傳統透鏡組的理想選擇，從而顯著縮減產品尺寸，實現輕薄化設計。
本研究中，我們基於Binary1與Binary2模型於長波紅外設計了兩種超穎透鏡，並通過同時作用這兩種透鏡實現影像疊加的效果。在比較有貼膠帶以及沒貼膠帶的情況下，兩者的MTF比值分別在1.5、2.4、2.9、3.3、5.9、7.4、8.4 lp/mm為1.38、1.34、1.79、2.41、3.88、4.24以及8.38。此外，本論文採用Propagation Phase與PB Phase（Pancharatnam-Berry Phase）兩種相位調製方法，各別製作了另外兩種應用在單波長下的超穎透鏡，進一步與消色差超穎透鏡進行影像清晰度的比較。研究結果表明，透過挑選具有高穿透率的單位晶胞結構所製作的超穎透鏡，其MTF與消色差超穎透鏡的MTF在1.5、2.4、2.9、3.3、5.9、7.4、8.4、11.8、14.7、29.4 lp/mm時，兩者MTF的比值依序為0.92、0.81、0.75、1.03、0.71、0.69、1.25、0.56、1.09以及0.93。在打入適當的偏振光源時，可有效提升PB Phase超穎透鏡的影像清晰度，使其接近消色差超穎透鏡的影像表現。
;With the increasing demand for lightweight and slim designs in electronic products, mobile phones have also been trending toward thinner designs. However, traditional lens systems commonly used in mobile phones require multiple lenses to adjust images, which limits the further reduction of the overall device size. In recent years, the emergence of metalens has provided a novel solution to this problem. Metalens, characterized by their lightweight and thin properties, can achieve optical functions equivalent to traditional multi-lens systems, such as achromatic function and wide field-of-view, with a single layer. As a result, metalens has gradually become an ideal choice for replacing traditional lens systems in many electronic products, significantly reducing product size and achieving lightweight and slim designs.
In this study, we designed two types of metalenses based on the Binary1 and Binary2 models at long infrared and achieved image superposition by simultaneously utilizing these two lenses. When comparing the cases with and without adhesive tape, the MTF (Modulation Transfer Function) improved by1.38, 1.34, 1.79, 2.41, 3.88, 4.24 and 8.38 at 1.5, 2.4, 2.9, 3.3, 5.9, 7.4, 8.4 lp/mm, respectively. Furthermore, we employed two phase modulation methods, Propagation phase and PB phase (Pancharatnam-Berry Phase), to separately fabricate two other metalenses designed for single-wavelength applications. These lenses are further compared with achromatic metalens in terms of image clarity. The results show that selecting unit cells with high transmittance exhibit MTF ratio of 0.92, 0.81, 0.75, 1.03, 0.71, 0.69, 1.25, 0.56, 1.09 and 0.93 at 1.5, 2.4, 2.9, 3.3, 5.9, 7.4, 8.4, 11.8, 14.7, 29.4 lp/mm, respectively, when compared to achromatic metalens. Additionally, introducing appropriate polarized light sources can effectively enhance the image clarity of PB Phase metasurface lenses, making their performance comparable to that of achromatic metalens. |
