Optical visualization

Optical (visual) Cracks, color, finish, scratches... 

Mahale, A.D. Prud Homme, R.K. Rebenfeld, L. Quantitative measurement of voids formed during liquid impregnation of nonwoven multifilament glass networks using an optical visualization technique. Polym. Eng. Sci. 1992, 32 (5), 319-326. 

Optical Visual Image overlaid with pixel grid. 

Precautions An illegal controlled substance that is habit forming. It is a strong hallucinogen that elicits optical (visual) or auditory (hearing) hallucinations, de-... 

E. Tada, H. Kaneko, Optical visualization of concentration field of Zn during galvanic corrosion of a Zn/steel couple, Corros. Sci. 52 (2010) 3421-3427. 

Thus, in the present writer s opinion, crystal chemistry modifications, resulting from iron lattice position or valence change, appear to create the optical (visual) effects we see in ferrite and nodule colors. Indeed, crystal structure, as always, determines what is observed in microscopy, and in many other fields of analysis. 

During the last few years optical visualization techniques have also been introduced. Among them the total internal reflection fluorescence excitation (TIFR) microscopy [4] and optical interference-enhanced reflection microscopy [5] appear to be the most promising nonintrusive techniques. Their resolution, however, does not even approach the resolution of atomic force microscope and optical techniques may thus serve as an image survey of nanobubbles at 300 nm level (diameter) which is so far their resolution limit. 

Liquid crystals (LCs) are widely used In Informationprocessing devices, for optical visualization of physical Influences (heat, IR, high-frequency radiation, pressure, etc.), for nondestructive testing, and for thermography. 

Optical Visual inspection Optical microscopy Brillouin scattering Photoelasticity Projection moire Shearography Optical holography Using visible part of electromagnetic spectrum (wavelength roughly between 400 and 700 nm)... 

One of the remarkable phenomena in nematic liquid crystals is the appearance of modulated structures under the action of an electric field [1-3]. These structures are characterized by the periodic distortion of the nematic director field in a certain preferred direction, and could be optically visualized as regular patterns of black and white stripes (domains) arranged perpendicular to the distortion plane. If the direction of distortion is degenerate in the layer plane, domains form a rectangular, hexagonal, or some other type of lattice, which could periodically transform to each other, i.e., oscillating domain patterns appear. 

In this context, the question of the correspondence between shear and birefringence bands has been raised by some authors [169,170], In recent studies of semidilute CPCl/NaSal solutions, simultaneous measurements of velocity profiles and optical visualizations were performed, showing a good agreement between shear and birefringence bands [157,253], However, this correlation did not seem so obvious for other systems [169, 170]. We will see later (Sect. 3.4.2) using time-resolved birefringence measurements that all these features could certainly be explained by the existence of fluctuations already revealed by velocimetry experiments. 

As fuel cell stacks are not transparent to visible light (unless a special-purpose stack with transparent windows and other parts was assembled), simple optical visualization is not possible. Therefore, visualization of fuel cells and fuel cell stacks requires the use of other forms of penetrating radiation for example, x-rays, neutron radiation (NR), or electron beams (scanning electron microscopy). Owing to the high sensitivity of neutron beams to water molecules, NR is capable of imaging the accumulation of liquid water in an opaque porous medium. Other methods for the vizualization of water content in fuel cells are also possible [e.g., nuclear magnetic resonance (NMR)]. 

The importance of surface concentration was discussed by Nygren et al. [5]. Their experiments indicated that direct optical visualization of a second protein layer applied upon a pre-existing one is possible only if the second layer reached a certain surface concentration that has a typical threshold value for each visualization system. 

Richter, S. Makovitzky, J. Topo-optical visualization reactions of carbohydrate-containing amyloid deposits in the respiratory tract. Acta Histochem. 2006, 108, 181-191. 

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