Near-field geometry

The near-field geometry of one-dimensional demonstration analysis is shown in the Figure 10. This test case is Ca-C-Mg-Na-K-Fe-Al-Si system because smectite, calcite and chalcedony are assumed in the buffer material region, and calcite and chalcedony are assumed in the hard rock region. 

Figure 10. Near-field geometry of one-dimensional demonstration analysis...

By deriving or computing the Maxwell equation in the frame of a cylindrical geometry, it is possible to determine the modal structure for any refractive index shape. In this paragraph we are going to give a more intuitive model to determine the number of modes to be propagated. The refractive index profile allows to determine w and the numerical aperture NA = sin (3), as dehned in equation 2. The near held (hber output) and far field (diffracted beam) are related by a Fourier transform relationship Far field = TF(Near field). 

Sun, W. X., and Shen, Z. X. 2003. Apertureless near-field scanning Raman microscopy using reflection scattering geometry. Ultmmicroscopy. 94 237 44. 

There is a need to improve probe geometries for high-resolution chemical imaging beyond the diffraction limit. This includes design (theory) and realization (reproducibility, robustness, mass production) of controlled geometry near-field optics. 

Although a vapor box or containment may be effective for concentration reduction, it may increase the explosion hazards. Higher explosion peak overpressure may be realized in the near field because of cloud geometry and partial blockage (Melhem and Croce, 1994). 

Sun WX, Shen ZX (2003) Apertureless near-field scarming Raman microscopy using refiection scattering geometry. Ultramicroscopy 94 237... 

Fig. 9 Excitation geometry for evanescent wave illumination of surface bound molecules. Sketch on the left show the smaller fiber at the periphery of the connector. Measured near-field intensity distribution shows the guided capillary modes...

FIGURE 8.17 (a) The geometry of a Sierpinski gasket and (b) three snapshots of the electric near field... 

The first application of the SNOM for the MO studies happened in 1992 [62], when it was demonstrated that near-field MO observation can be obtained in the same manner as conventional far-field observation— that is, by using two cross-polarizers. Betzig et al. [62] visualized 100-nm magnetic domains and claimed spatial resolution of 30-50 nm. The possibility of MO domain imaging was confirmed in both the transmission regime (Faraday geometry) [63,64] and the reflection regime (Kerr microscopy) [65-67]. 

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