Near-field scanning optical applications

E. Betzig, A. Lewis, A. Harootunian, M. Isaacson, and E. Kratschmer, Near-Field Scanning Optical Microscopy (NSOM) -Development and Biophysical Applications, Biophys. J. 49, 269 (1986)... 

LT. Nieman, G.M. Krampert, and R. E. Martinez, An Apertureless Near-Field Scanning Optical Microscope and its Application to Surface-Enhanced Raman Spectroscopy and Multiphoton Fluorescence Imaging, Rev. Sci. Instrum. 72, 1691 (2001)... 

Betzig. E. Lewis, A. Harootunian. A. Isaacson, M. Kratschmer, E. Near-field scanning optical microscopy (NSOM)—Development and biophysical applications. Biophys. J. 1986. 49 (1). 269-279. 

Near-field Raman imaging with a scanned probe has been reported [18, 19]. However, the technique is painfully slow (5-10 h, even for strong scatterers) and it has found very little use. Acquisition time can be decreased by using a polystyrene bead as a very high numerical aperture immersion lens. Working at 532 nm, Kasim et al. used a 60x/1.2 immersion aperture as an optical tweezer to simultaneously position the bead and operate it as a high NA lens [20]. They obtained a spatial resolution of about 80 nm on doped silicon with a few minutes scan time (Fig. 5.1). However, because of the need for a relatively smooth surface and a very intense scatterer, this technique is not likely to find much application in biomedical or pharmaceutical applications [21, 22],... 

B. Hecht, B. Sick, U. P. Wild, V. Deckert, R. Zenobi, O. J. F. Martin and D. W. Pohl, Scanning near-field optical microscopy with aperture probes Fundamentals and applications, J. Chem,. Phys. 112, 7761 (2000). 

The paper describes the application of singular-value decomposition method for resolution estimation and resolution enhancement in near-field optics with focus at scanning near-field microscopy. Analysis of general properties of singular functions and associated singular values is presetted. 

When the diffusion is very slow and high spatial resolution is more important than high frame rates, such as in a polymer film, illumination mode scanning near-field optical microscopy can be used to image the diffusion of individual fluorophores. This application will be discussed in the Section V.B. 

Hecht B, Sick B, Wild UP, Deckert V, Zenobi R, Martin OJF, Dieter DW (2000) Scanning near-field optical microscopy with aperture probes fundamentals and application. J Chem Phys 18 112... 

The fundamental principals underlying the scanning near-field optical microscopy technique (variously referred to as SNOM or NSOM in the literature) are described. The key features of the practical application of RSNOM are discussed, an example RSNOM system is described, and an example application is presented. 

Guttroff, G., J. M. Keto, C. K. Shih, A. Anselm and B. G. Streetman (1996). "A design of reflection scanning near-field optical microscope and its application to algaas/gaas heterostructures." Applied Physics Letters 68(25) 3620-3622. 

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