ABSTRACT
Nowadays, t he ne ar- eld opt ical m icroscopy c ommunity i s facing ne w a nd e xciting c hallenges a s d iscussed t hroughout this chapter. However, we would like to begin by considering two e vents t hat to ok p lace more t han a c entury a go but s till maintain their relevance. It was precisely in 1873, when Ernest Karl Abbé stated a rigorous criteria, the well-known diff raction limit, that establishes the maximal resolving power that can be obtained in optical microscopy (Abbé 1873). Only 1 ye ar earlier, Claude Monet painted “Impression, soleil levant” opening o cially t he school of impressionism, which revolutionized the concept of painting. e de ned sign of the brush on the canvas was passed over by a new concept: color patches were demanded to create the atmosphere and the impression of a sunrise at Le Havre harbor. If we look at the coincidence of these two events in our recent history, both of them propose the same concept: we cannot observe and describe the reality with sharp boundaries,
we can only achieve a bl urred sig ht on t he world. In t he case of opt ical m icroscopy, t he l imit of our observation capabilities has been xed by the di raction limit for more than one century until the mid1980s when the near- eld scanning optical microscope (NSOM) was realized and the di raction limit was broken for the rst time.
