Yan Bing, Song Yang, Yang Xibin, Xiong Daxi, Wang Zengbo
Appl Opt. 2020 Mar 10;59(8):2641-2648. doi: 10.1364/AO.386504.
Microsphere-based subwavelength imaging technique was first demonstrated in 2011. After nearly a decade of efforts, such technique has spawned numerous interests in fields such as laser nano-machining, imaging, sensing, and biological detection. For wider industrial-scale application of the technique, a robust and low-cost objective lens incorporating a microsphere lens is highly desired and sought by many researchers. In this work, we demonstrate a unibody microscope objective lens formed by tipping a high-index microsphere onto a plano-convex lens and subsequently fitting them into a conventional objective lens. We call this the plano-convex-microsphere (PCM) objective, which resembles the appearance and operation of an ordinary microscope objective while providing super-resolving power in discerning subwavelength 100 nm features ($\lambda /{4}.{7}$λ/4.7) in air and far-field conditions. The imaging performance of the PCM objective, along with the working distance, has been systematically investigated. It has a calibrated resolution of $\lambda /{3}$λ/3 in the far field, a numerical aperture of 1.57, and a working distance of 3.5 µm. With the assistance of a scanning process, larger-area imaging is realized. The PCM objective can be easily adapted to existing microscope systems and is appealing for commercialization.
基于微球的亚波长成像技术于2011年首次得到证明。经过近十年的努力，该技术在激光纳米加工、成像、传感和生物检测等领域引发了众多关注。为了使该技术在更广泛的工业规模上得到应用，许多研究人员迫切需要并寻求一种坚固且低成本的包含微球透镜的物镜。在这项工作中，我们展示了一种一体式显微镜物镜，它是通过将一个高折射率微球倾斜放置在一个平凸透镜上，然后将它们安装到一个传统物镜中形成的。我们将其称为平凸 - 微球（PCM）物镜，它在外观和操作上类似于普通显微镜物镜，同时在空气和远场条件下分辨亚波长100 nm特征（$\lambda /{4}.{7}$）时具有超分辨能力。我们系统地研究了PCM物镜的成像性能以及工作距离。它在远场的校准分辨率为$\lambda /{3}$，数值孔径为1.57，工作距离为3.5 µm。借助扫描过程，可以实现更大面积的成像。PCM物镜可以很容易地适配到现有的显微镜系统中，并且具有商业化的潜力。
