背景介质对微球透镜像差和成像特性的影响

Influence of Background Medium on Aberration and Imaging Characteristics of Microsphere

摘要

微球透镜辅助显微技术凭借其非侵入性和无需标记等特性，在生物成像、物理化学等领域具有巨大的应用潜力。但值得注意的是，微球透镜因为其形状特征，会产生明显像差。研究影响微球透镜像差的因素并降低其像差，对提高微球透镜辅助超分辨成像技术具有积极意义。在本文中，我们系统研究了背景介质的折射率及其浸没程度，对微球透镜像差和成像特性的影响。我们通过实验结果和模拟发现，随着微球透镜与背景介质的相对折射率增大，微球透镜所成图像的畸变随之增大，并且背景介质的浸没程度会明显影响微球透镜的像差。当背景介质的浸没程度约为一半时，微球透镜的成像性能最佳，可清晰分辨周期为 250nm 的颗粒阵列。

Abstract

Microsphere-assisted microscopy has great potential for applications in bio-imaging, physical chemistry, due to its non-invasive and label-free nature. However, it should be noted that microsphere lenses produce significant aberrations due to their shape characteristics. Investigation of the factors affecting the aberration of microsphere lenses and reduction of their aberration are of positive significance for the improvement of microsphere-assisted super-resolution imaging technology. Herein, we systematically investigate the effects of the refractive index of the background medium and its immersion degree on the aberration and imaging characteristics of microsphere lenses. We found that as the relative refractive index between the microsphere lens and the background medium increases, the distortion caused by the microsphere increases. And the immersion degree of the background medium significantly affects the aberration of the microsphere lens. When the microsphere is semi-immersed in the background medium, it has the least aberration and works best for imaging, allowing it to clearly identify a particle array with a spacing of 250 nm.

关键词

光学显微镜 / 微球透镜 / 超分辨成像 / 像差

Key words

optical microscope / microsphere lens / super-resolution imaging / aberration

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基金资助

国家自然科学基金项目(61475073, 61673287)

南京工业职业技术大学引进人才科研启动基金项目(YK24-14-01)