  The near field scanning optical microscopy (NSOM) is not only a tool for
imaging of objects in the sub wavelength limit but also a prominent
characteristic tool for understanding the intrinsic properties of the
nanostructures. The effect of strong localized surface plasmon resonance
absorption of excitation laser in the NSOM images for Au nanoparticles is
observed. The role of electronic transitions from different native defect
related energy states of AlGaN are also discussed in understanding the NSOM
images for the semiconductor nanowire.
