Angle-of-incidence

There are two mutually exclusive requirements in SIMS there is a need for high sensitivity, which is optimum at normal incidence, and as in AES and XPS, a need for good depth resolution which is optimum at glancing incidence. The best solution seems as before to involve rotation of the sample during sputtering, which produces a depth resolution relatively independent of the incidence angle so that high sensitivity can still be achieved. 

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Let us consider the scheme showed in Fig. I to calculate the field scattered by a rough cylindrical surface (i.e. a wire). The wire is illuminated by a monochromatic, linearly polarized plane wave at an angle of incidence a with its axis of symmetry. The surface is described, in a system fixed to the wire, by p = h (cylindrical coordinates. We shall denote the incident wave vector lying on the x-z plane as kj and the emergent wave vector simply as k. 

Due to the limitation posed by the initial electrical leakage signal and by the chosen angle of incidence of 52 deg. diffracted signals from 8 mm deep machined notch were hidden. Defects with depth exceeding 12 mm could be detected and sized. The same difficulty was observed when the thickness of the sample was less than 30 mm. 

The aim of the experiment was to study the transmission of a signal through the weld and to measure the frequency and phase dependencies of parameters of acoustic signals from the angle of incidence and beam path within the weld volume. One of the shift of the spectral characteristics the signal is shown in Figure 4(a,b). 

Fig. 2 shows the CFRP-sandwich specimen and the transducer mounted on the scanner. Fig. 23 presents a C-scan of the specimen as first interesting result. Only the defects visible from the outside are indicated. The distance between transducer and specimen was smaller than the focal length, so that the angle of incidence at the edge of the sound beam converts the longitudinal waves to Rayleigh-waves in the specimen. These waves provide a very sharp image of the surface. This method opens the possibility for a non-contact acoustic microscope. 

The phase velocity is directly linked to the angles of incidence by the Snell-Descartes law ... 

The diffraction pattern consists of a small number of spots whose symmetry of arrangement is that of the surface grid of atoms (see Fig. IV-10). The pattern is due primarily to the first layer of atoms because of the small penetrating power of the low-energy electrons (or, in HEED, because of the grazing angle of incidence used) there may, however, be weak indications of scattering from a second or third layer. 

Experimentally, it is common for LEED and Auger capabilities to be combined the basic equipment is the same. For Auger measurements, a grazing angle of incident electrons is needed to maximize the contribution of surface... 

Optical second-harmonic generation (SHG) has recently emerged as a powerful surface probe [95, 96]. Second harmonic generation has long been used to produce frequency doublers from noncentrosymmetric crystals. As a surface probe, SHG can be caused by the break in symmetry at the interface between two centrosymmetric media. A high-powered pulsed laser is focused at an angle of incidence from 30 to 70° onto the sample at a power density of 10 to 10 W/cm. The harmonic is observed in reflection or transmission at twice the incident frequency with a photomultiplier tube. 

Figure Bl.26.17. (a) Observed and calculated ellipsometric [A(1), T(>l)] spectra for the Y2O3 film on vitreous silica. Angle of incidence 75°. (b) Best-fit model of the Y2O3 film on vitreous silica (Chindaudom P and Vedam K 1994 Physics of Thin Films vol 19, ed K Vedam (New York Academic) p 191).

The blaze wavelength is that wavelength for which the angle of reflectance from the groove face and the angle of reflection (usually the angle of incidence) from the grating are identical. 

Gloss, or surface luster, is the property of a surface to reflect light specularly. It is associated with such phenomena as shininess, highlight, and reflected images. The gloss of paper is usually quantified with a spectrophotometer which measures light at a variety of angles of incidence and reflection. 

The first paper about NiFe layers evaporated under an angle was pubHshed in the early 1960s (40). The films prepared this way are often called obHque-incidence or angle-of-incidence films. It was found that these kinds of films show an anisotropy whose strength depends on the angle of incidence of the atoms (a/ during deposition (Fig. 15). If is between 0 and 65 the anisotropy Hes parallel to the film plane and perpendicular to the incidence plane. 

The relation between the columnar inclination angle (P) and the angle of incidence (a of the evaporation flux was found to be 2tan/5 = tana (45). The so-called tangent rule is not always vafld in a variety of experimental situations. 

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