ABSTRACT
In this chapter, we will present an overview of near-eld scanning optical microscopy (NSOM), a technique that surpasses the optical diffraction limit through the use of subwavelength apertures and other structures to conne optical elds to nanometer-scale dimensions. The technique is a type of scanning-probe microscopy, having roots in the development of scanning tunneling microscopy (STM) and atomic force microscopy (AFM). The chapter will focus on tip-enhanced (apertureless) NSOM due to its superior resolution and the unique challenges associated with its implementation. Furthermore, there is already an extensive body of literature dealing with aperture-type NSOM (Novotny and Hecht, 2006).
