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arXiv · 2108.06242

Super-resolution imaging with patchy microspheres

Qingqing Shang·Fen Tang·Lingya Yu·Hamid Oubaha·Darwin Caina·Sorin Melinte·Chao Zuo·Zengbo Wang·Ran Ye
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Abstract

The diffraction limit is a fundamental barrier in optical microscopy, which restricts the smallest resolvable feature size of a microscopic system. Microsphere-based microscopy has proven to be a promosing tool for challenging the diffraction limit. Nevertheless, the microspheres have a low imaging contrast in the air, which hinders the application of this technique. In this Letter, we demonstrate that this challenge can be effectively overcome by using partially Ag-plated microspheres. The deposited Ag film acts as an aperture stop that blocks a portion of the incident beam, forming a photonic hook with oblique near-field illumination. Such a photonic hook significantly enhanced imaging contrast, as experimentally verified by imaging Blu-ray disc surface and silica particle arrays.

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Qingqing Shang, Fen Tang, Lingya Yu, Hamid Oubaha, Darwin Caina, Sorin Melinte, Chao Zuo, Zengbo Wang, Ran Ye. 2021-08-13. Super-resolution imaging with patchy microspheres. https://doi.org/10.3390/photonics8110513

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