Use of a resonant optical cavity to increase the spectral density of near-field optical images

It has already been shown that the combination of an optical ring-cavity an d of a Scanning tunneling optical microscopy (STOM) drastically reduces the evanescent decay of the evanescent field above the sample surface [Opt. Le tt. 24 (1999) 1811] and accordingly, the spatial resolution is increased, I n this paper a time-frequency analysis allows us to compare the quality of near-field images which are obtained for different positions along the cavi ty resonance curve. (C) 2001 Elsevier Science B.V, All rights reserved.