Optical microscopy OM

The information obtained in the OM normally concerns the size, shape and relative arrangement of visible features. Local measurement of optical constants such as the refractive index (Section 2.2.2) and the birefringence (Section 2.2.3) is also possible. Many techniques are used to enhance contrast, and thus make more of the structure visible. Images are typically recorded photographically, on video tape for the study of dynamic processes, or in a computer system for digital image analysis. 

Simple microscopes have only one imaging lens (though this may have several elements) and 

The eye can detect variations in light intensity and in colour. Light of different states of polarization cannot be distinguished with the unaided eye. There are several techniques by which a variation in optical path (OP) is converted to a corresponding variation in light intensity (Fig. 11.2). The variation in optical 

The resolution is defined as the least distance between two points that can be recognized as two separate items. Rayleigh showed that two points can be resolved if the light intensity between the points is 85% or less of the maximum value at the centres of the points. The resolution (d) that is controlled by diffraction is given by  

All optical components are imperfect. Lenses suffer from different so-called aberrations chromatic (light of different wavelengths is refracted differently), spherical, coma, astigmatism, field curvature (the sharp image falls on a curved surface) and distortion. Modem lenses correct for some of the existing aberrations achromats and apochromats correct for chromatic aberration. Lenses corrected for field 

The components in a transmission optical microscope are shown schematically in Fig. 11.4. The 

Series II includes the specimen plane. The field iris controls the diameter of the area that is viewed. Pointers or scales must be inserted in the primary image plane. Series I is related to the filament. An image of the filament is found at the back focal plane of the objective. The principle behind the uniform illumination of the specimen is the so-called Kohler illumination. Every part of the filament illuminates every part of the specimen. The correct illumination is obtained by adjusting the collector lens and the condenser. Detailed instructions are provided in microscopy manuals. 

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By optical microscopy (OM), birefringent structures are observed in semicrystalline polymers, characterized by "Maltese-crosses" under crossed polars as seen in Figure 6. As these structures grow symmetrically in three dimensions... 

Figure 6 Spherulites of isotactic poly-l-butene (a, during growth) and of polyethylene (b, after completion) by optical microscopy (OM) under crossed polars. Reproduced from Ref. [3] with permission of John Wiley Sons, Inc.

Techniques of optical microscopy (OM) are well known and often used for the examination of fibers and yams from archaeological textiles. Many texts provide the fundamentals of the technique (e.g. 40-43). Some manuscripts describe the methods that may be employed in the study of archaeological materials in particular (44, 45), while others report the results of optical microscopic examination in identification and characterization of archaeological fibers (e.g., 12, 46). 

Optical microscopy (OM) Reflection Transmission Phase contrast Polarized light... 

Optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) data obtained from the surface of metallographic section of initial alloy were compared with those from the surface subjected to hydrogen... 

Fig. 8 Endothelialization on PEU surfaces modified by MPEO-derived SMAs. A Un-treated PEU surface (control) imaged by optical microscopy [OM] B MPEO-OH (without functional endgroups at the end of PEG spacers) as SMA imaged by scanning electronic microscopy [SEM] basic amino acid (typically lysine)-functionalized MPEO derivatives as SMA by C OM and D SEM arginine-glycin-aspartic acid tri-peptide sequence [RGD]-functionalized MPEO derivatives as SMA by E OM and F SEM [82,83]. Reproduced from [180,181]...

Much effort has been devoted to investigating the detailed architectures and the construction of spherulites. Early investigations of the crystallization of polymers through optical microscopy (OM) [7,8] posited that polymer spherulites consisted of radiating fibrous crystals with dense branches to fill space. Later, when electron microscopy (EM) became available, spherulites were shown to be comprised of layer-like crystallites [9,10], which were named lamellae. The lamellae are separated by disordered materials. In the center of the spherulites, the lamellae are stacked almost in parallel [5,6,11-15]. Away from the center, the stacked lamellae splay apart and branch, forming a sheaf-like structure [11,13-15]. It was also found that the thicknesses of lamellae are different [5,6,11,12]. The thicker ones are believed to be dominant lamellae while the thinner ones are subsidiary lamellae. 

Determination of Failure Location Optical Microscopy (OM), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM). 

There are several techniques described to characterize the microparticles. To analyze the shape and size of samples, particle size distribution (PSD), optical microscopy (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are the most employed. When the... 

Zia et al. [115] presented that nanostructure and morphological pattern of chitin/bentonite clay based polyurethane bionanocomposites. The clay dispersion within chitin was characterized by both XRD and optical microscopy (OM), which is the most frequently, used and approachable methods to study the structure of nanocomposites. There are one acetamide (-NHCOCH3) group at C-2 position and two (two hydroxy (-OH)) groups at C-3 (C3-OH) and C-6 (C6-OH) positions on chitin chains which can serve as the coordination and reaction sites [95], The crystalline structure of chitin has been reported by many researchers [96],... 

Optical microscopy (OM), e.g. [87,96,97] is useful if the samples can be prepared appropriately and the domain size is larger than the wavelength of light. 

Optical microscopy (OM), polarized light microscopy (PLM), phase contrast microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and scanning transmission electron microscopy (STEM) are the methods normally used for identification and quantification of the trace amounts of asbestos fibers that are encountered in the environment and lung tissue. Energy-dispersive X-ray spectrometry (EDXS) is used in both SEM and TEM for chemical analysis of individual particles, while selected-area electron diffraction (SAED) pattern analysis in TEM can provide details of the cell unit of individual particles of mass down to 10 g. It helps to differentiate between antigorite and chrysotile. Secondary ion mass spectrometry, laser microprobe mass spectrometry (EMMS), electron probe X-ray microanalysis (EPXMA), and X-ray photoelectron spectroscopy (XPS) are also analytical techniques used for asbestos chemical characterization. 

Optical Microscopy (OM) has been and continues to be a useful tool for rapid analysis of filler macrodispersions in polymer matrices because of its relative simplicity and minimal sample preparation. Traditionally, however,... 

Microscopy methods, in the broader sense of methods that provide direct morphology imaging, can be divided into several categories optical microscopy (OM),... 

The hardness of GST is only 2.3—2.4 GPa [5], while the hardness values of A1 and Cu are 0.5—1.2 and 3.0 GPa, respectively. So GST is a relatively soft material. Hence, it can be easily scratched during CMP by hard materials like the pad, agglomerated large silica particles, diamond particles from conditioner, and so on. Figure 19.2 shows a typical optical microscopy (OM) image of a post-CMP GST surface polished using... 

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