A Linear, Direct Far-Field Subwavelength Imaging Method: Microparticle-Assisted Nanoscopy

Abstract

Microparticle-assisted nanoscopy (MAN) is a novel emerging technique of direct far-field deeply subwavelength imaging, which has been developed since 2011 as a set of experimental techniques. For a decade, the capability of a simple glass microsphere without fluorescent labels or plasmonic elements to grant a direct, broadband, deeply subwavelength image of a nanostructured object was unexplained. Four years ago, the explanation of MAN via the suppression of diffraction was suggested by the author of the present overview. This explanation was confirmed by extensive full-wave simulations, which agreed with available experimental data and revealed new opportunities for MAN. Although the main goal of the present paper is to review recent works, state-of-the-art concepts in MAN are also reviewed. Moreover, so that the peculiarities of MAN are better outlined, its uniqueness compared to other practically important methods of far-field subwavelength imaging is also discussed.

Keywords

• super-resolution
• magnification
• diffraction
• geometrical optics
• imaging beam
• virtual source