Near field scanning optical orientation

Figure Bl.22.11. Near-field scanning optical microscopy fluorescence image of oxazine molecules dispersed on a PMMA film surface. Each protuberance in this three-dimensional plot corresponds to the detection of a single molecule, the different intensities of those features being due to different orientations of the molecules. Sub-diffraction resolution, in this case on the order of a fraction of a micron, can be achieved by the near-field scaiming arrangement. Spectroscopic characterization of each molecule is also possible. (Reprinted with pennission from [82]. Copyright 1996 American Chemical Society.)...

Hollars C W and Dunn R C 2000 Probing single molecule orientations in model lipid membranes with near-field scanning optical microscopy J. Phys. Chem 112 7822-30... 

It is instructive to compare the SH microscopy results with the near-field images of Fig. 9.6 which show the same kind of light-emitting nanofibers. The spatial resolution of SH microscopy is lower ( 700 nm) compared with scanning near-field optical microscopy (SNOM) the contrast ratio, however, is much better. Nevertheless, it recently also became possible to determine molecular orientations via SH-SNOM (Fig. 9.14). 

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