The recent exploitation of near field optics opened a new branch of light microscopy beyond the diffraction limit. With scanning near field optical microscopy a lateral resolution of 20 and 50 nm was obtained in transmission and reflection, respectively. In a novel optical tunneling mode, also the topography of pure phase objects has been imaged at a resolution of 50 nm laterally and 1 nm vertically.
Fischer, U. Ch.; Dürig, U. T.; and Pohl, D. W.
"Scanning Near Field Optical Microscopy (SNOM) in Reflection or Scanning Optical Tunneling Microscopy (SOTM),"
Scanning Microscopy: Vol. 3
, Article 1.
Available at: https://digitalcommons.usu.edu/microscopy/vol3/iss1/1