Reflection of light

Figure Bl.26.9. Schematic diagram showing the reflection of light incident at an angle from a medium with refractive index n tln-ough a film of thickness d with refractive index n. ...

Fig. 2. Waveguide stmcture showiag the total internal reflection of light. The diameter, is 50 p.m for a standard multimode system, 62.5 p.m for a large...

Surface Finish. As well as influencing the rate of metal removal, electrolytes also affect the quality of surface finish obtained in ECM. Depending on the metal being machined, some electrolytes leave an etched finish. This finish results from the nonspecular reflection of light from crystal faces electrochemicaHy dissolved at different rates. Sodium chloride electrolyte tends to produce a kind of etched, matte finish when used for steels and nickel aHoys. A typical surface roughness average, Ra is about 1 ]lni. 

Delusterants reduce the transparency, iacrease the whiteness, and alter the fiber s reflectance of light. Ti02 is the delusterant of choice for aU melt-spun fiber types because of its high cover, whiteness, and chemical and thermal stabUity. Nylon is translucent and requires ia most textile and... 

Auxiliary data are the sizes of bubbles and droplets. These data and the holdups of the two phases are measured by a variety of standard techniques. Interfacial area measurements utihze techniques of transmission or reflection of light. Data on and methods for finding sohi-bihties of gases or the relation between partial pressure and concentration in hquid are also well estabhshecT... 

Black smoke (BS) is a particulate measure that typically contains at least 50% respirable particulates smaller than 4.5 mm in aerodynamic diameter, sampled by the British smokeshade (BS) method. The reflectance of light is measured by the darkness of the stain caused by particulates on a white filter paper. The result of BS sampling depends on the density of the stain and the optical properties of the particulates. Because the method is based on reflectance from elemental carbon, its use is recommended in areas where coal smoke from domestic fires is the dominant component of ambient particulates. 

The relationships in Figure 4-11 are strongly reminiscent of those that exist for ordinary light diffracted from a concave Rowland grating.24 To understand this process, it is best to look first at the reflection of light from a concave mirror. 

Table 2. Reflection of light at an interface Index of refraction and percentage of energy reflected at an air-medium interface for glass, silicon and HgCdTe.

The object under test may be examined by its absorbance or reflectance of light. 

Creams are semisolid emulsion systems having a creamy appearance as the result of reflection of light from their emulsified phases. This contrasts them with simple ointments, which are translucent. Little agreement exists among professionals as to what constitutes a cream, and thus the term has been applied both to absorption bases containing emulsified water (w/o emulsions) and to semisolid o/w systems, which are physicochemically totally different, strictly because of their similar creamy appearances. Logically, classification of these systems should be based on their physical natures, in which case absorption bases would be ointments and the term cream could be reserved exclusively for semisolid o/w systems, which in all instances derive their structures from their emulsifiers and internal phases. 

The appearance of signals takes place in form of a substance of a given state (gaseous, liquid, precipitate), change of colors by absorption or reflection of light, or emitted and absorbed radiation. Spectroscopic signals... 

Pearlescent pigments contain small flakes or platelets of the mineral mica that are additionally coated with a very thin layer of titanium dioxide. The simultaneous reflection of light from many layers of small platelets creates an impression of luster and sheen. By varying the thickness of the coating on the surface of the mica particles, pigment manufacturers can achieve a range of colors for the pearlescent effect. 

Figure 12,4.1 The multiple reflection of light from microscopic oxide layers of different dimensions leads to constructive and destructive interference of light waves, producing a particular color effect. Different thicknesses reflect different colors.

We consider the reflection of light at the surface of a metal with refractive index nm in the vacuum. For normal incidence the ratio of reflected to incident light (reflectivity) is ... 

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