Superresolution microscopy in far-field by near-field optical random mapping nanoscopy

Obtaining an optical resolution of better than 200 nm requires rather slow and complicated techniques such as near-filed scanning optical microscopy. Here, we demonstrate a method of optical near-field acquisition by far-field microscopy—near-field optical random mapping nanoscopy. An object surface is randomly scanned by nanoparticles undergoing Brownian motion. The resolution of the method is restricted only by the size of observable nanoparticles (as small as 10 nm). We have achieved a resolution of 96 nm by using an objective with NA = 0.4. Thus, the resolution of the given far-field microscope is improved in more than six times.