Differential near-field scanning optical microscopy

Nano Lett. 2006 Nov;6(11):2609-16. doi: 10.1021/nl062110v.


We theoretically and experimentally illustrate a new apertured near-field scanning optical microscopy (NSOM) technique, termed differential NSOM (DNSOM). It involves scanning a relatively large (e.g., 0.3-2 mum wide) rectangular aperture (or a detector) in the near-field of an object and recording detected power as a function of the scanning position. The image reconstruction is achieved by taking a two-dimensional derivative of the recorded power map. Unlike conventional apertured NSOM, the size of the rectangular aperture/detector does not determine the resolution in DNSOM; instead, the resolution is practically determined by the sharpness of the corners of the rectangular aperture/detector. Principles of DNSOM can also be extended to other aperture/detector geometries such as triangles and parallelograms.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Equipment Design
  • Equipment Failure Analysis
  • Microscopy, Scanning Probe / instrumentation
  • Microscopy, Scanning Probe / methods*
  • Nanotechnology / instrumentation
  • Nanotechnology / methods*
  • Particle Size
  • Sensitivity and Specificity
  • Surface Properties