Microscopic imaging

A first example of application of microtomography is taken from life sciences. Here X-ray microscopy and microtomography allows to reconstruct the internal three-dimensional microstructure without any preparation and sometimes even of living objects. Fig. la shows an X-ray transmission microscopical image of bone (femoral head). Several reconstructed cross-sections are shown in Fig.lb. Fig.lc shows the three-dimensional reconstruction of this bone. 

In the case of Langmuir monolayers, film thickness and index of refraction have not been given much attention. While several groups have measured A versus a, [143-145], calculations by Knoll and co-workers [146] call into question the ability of ellipsometry to unambiguously determine thickness and refractive index of a Langmuir monolayer. A small error in the chosen index of refraction produces a large error in thickness. A new microscopic imaging technique described in section IV-3E uses ellipsometric contrast but does not require absolute determination of thickness and refractive index. Ellipsometry is routinely used to successfully characterize thin films on solid supports as described in Sections X-7, XI-2, and XV-7. 

Figure Al.7.2. Large-scale (5000 Atimes 5000 A) scanning tiimielling microscope image of a stepped Si (111)-(7 X 7) surface showing flat terraces separated by step edges (courtesy of Alison Baski).

Weiss P S and Eigler D M 1993 Site dependence of the apparent shape of a molecule in scanning tunnelling microscope images benzene on Pt(111) Rhys. Rev. Lett. 71 3139... 

Fisher A J and Bldchl P E 1993 Adsorption and scanning-tunneling-microscope Imaging of benzene on graphite and M0S2 Phys. Rev. Lett. 70 3263-6... 

In contrast to the older techniques, a newer method is to use a scanning tuimeling electron microscope to deposit metal coatings in microscopic images as small as 0.001 pm. The ultimate surface metallization techniques allow deposition of metals atom by atom in controlled three-dimensional arrays. 

Video-Enhanced Contrast. This technique is more expensive but much more effective than any other contrast-enhancing technique (15). Since the 1970s, the development of video processing of microscopical images has resulted in electronic control of contrast. As Shinya InouH, author of a classic text in the field, states "We can now see objects that are far too thin to be resolved, and extract clear images from scenes that appeared too fuzzy, too pale, or too dim, or that appeared to be nothing but noise" (16). The depth of the in-focus field can now be expanded or confined, very thin but very sharp optical sections can be produced, and a vertical succession of these images can be accumulated to reconstmct thicker stmctures in three dimensions (16). 

Fig. 4. Aggregate size distributions by electron microscope image analysis (D and centrifugal (Z9 sedimentations for N220 and N351 carbon blacks (8).

Figure 5 Atomic force microscope images of an aluminum film deposited on ambient (a) and heated (b) Si substrates. The scales are 15 pm x 15 pm (a) and 20 pm x 20 pm (b). The grain size can be clearly observed (Courtesy of M. Lawrence A. Dass, Intel Corporation).

Figure 11.1. Scanning tunnelling microscope image of a periodic array of Fe islands nucleated on the regular dislocation network of a Cu bilayer deposited on a platinum (111) face (after Urune...

FIG. 3 (a) Transmission electron microscopic image of Ni-Al-Mo alloy with Mo... 

Fig. 16.6. Atomic force microscope image of a polycarbonate microfiltration membrane (cyclopore), 0.2 p,m pore size.

Fig. 16.8. Atomic force microscope image of anodise microfiltration membrane, 0.2 xm pore size.

An electron microscope image of a drug capsule as it bursts open, revealing the tiny microcapsules inside. The image has been digitally colored. 

Figure 6a. Microscopic image of chromosomes (courtesy Jean-Claude Bemengo from the Centre Commun de Quantimetrie, University Claude Bernard, Lyon, France).

Figure 6b. Microscopic image of chromosomes improved by blind deconvolution.

All aspects of interferogram and experimental data acquisition and optical test rig control are provided by a computer program that also performs film thickness evaluation. It is believed that the film thickness resolution of the colorimetric interferometry measurement technique is about 1 nm. The lateral resolution of a microscope imaging system used is 1.2 /u,m. Figure 10 shows a perspective view of the measurement system configuration. This is an even conventional optical test rig equipped with a microscope imaging system and a control unit. 

Fig. 35—The typical optical microscopic images (500X) of the first crack in the scratch test.

Figure 35 shows the optical microscopic images of the first crack point on the sample surface. The scratch scar of monolayer Sample 1 has the feature of brittleness. However, there is an obvious crack along the scratch scar of Sample 2 before the coating delamination. This indicates that mono-layer Sample 2 has the feature of ductility, and the adhesion between the film and the substrate is poor. However, there is no obvious crack before the delamination in the scratch scars of other samples. The feature of multilayer Samples 3 and 4 is different from monolayer Samples 1 and 2. There are no obvious cracks in the scratch scars of Samples 5 and 6, except several small cracks along the edge of the scars. These... 

FIG. 6 Atomic force microscopic images of DNA/PLL/SPLL complexes (1 3 10 initial ratio) absorbed on mica in 25 mM HEPES, 1 mM NiCb, pH 7.5. (Reprinted from Ref. 5, copyright 1999 Oxford University Press.)... 

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