Laboratoire d'Optique P.M. Duffieux (CNRS UMR 6603), Université de Franche-Comté, Institut des Microtechniques, 25030 Besançon Cedex, France
Gratings can be considered as resonant structures in near-field. The enhancement of the intensity recorded by Scanning Near-Field Optical Microscopes (SNOM) is due to interferences in relation with the ratio of the wavelength to the product of the optical index by the period of the grating. We discuss the effect of this ratio (in the range 0.9, 1.1) on the intensity patterns. The influence of the polarization on near-field data is analyzed in both theoretical computations and experimental result.
(Received July 2 1998)
(Revised September 29 1998)
(Accepted October 29 1998)
(Online publication March 15 1999)
* This paper was presented at the special CFMCP colloquium held at Strasbourg-Illkirch the July 1st-3rd, 1998.