Refractive optics

PE). Then, the mixtures were placed in an ultrasonic cleaner for 15 minutes to obtain a uniform mixture oil. The viscosity and the optical refractive index of these base oils and mixture oils were given in Table 7. 

Another early fiber optic refractive "sensor" was the one for measurement of temperature and salinity variations of sea water31. The sensing region consisted of a partly uncovered light guide. It detects salinity variations in water of known temperature, and temperature variations in water of known salinity with an accuracy of +/- 2 g/L and 1 °C, respectively, at NaCl concentrations of 300 g/L. 

The fiber optic refractive index sensor finds use in biomedical applications. It uses a silicon chip with optical waveguides forming ring resonators. When the laser wavelength is scanned, the resonators cause dips in the power transmitted through the device. The wavelength at which these dips occur is a measure of the refractive index of the substance in contact with the chip surface. 

These values give an indication of the fractional variation of the optical refractive index and the Rayleigh velocity as a function of the dopant concentration. However, the relationship may not be linear over the range indicated (especially Ge02) and the original data should be consulted for accurate purposes (Jen etal. 1989). 

In passing, we note that reaction 17.39 is also used in the conversion of natural rutile ore, which is usually red-brown because of its iron(III) content, to pure Ti02, which is used as a filler for paper, as a white pigment in paints, and as a photocatalyst (Sections 10.4 and 14.4.2). The high optical refractive index gives Ti02 the best available covering power in... 

The salt is very soluble in water—100 grms. of cold water dissolve 16 7 parts of the salt, and 100 parts of hot water dissolve 100 parts of salt—the soln. loses ammonia when heated. J. M. Thomson and W. P. Bloxam found that the supersaturated soln. crystallizes when seeded with a crystal of the solid salt—this is taken as. showing the existence of the undissociated solid in the soln. J. M. van Bemmelen fpund that but very little ammonia can be separated by dialysis. J. Thomsen gives —10 8 Cals, for the heat of soln. of a mol. of the salt in 800 mols. of water at 18°. E. Doumer gives 0 303 for the optical refraction of the salt in dil. soln., and 45 for the mol, refraction. 

Fig. 17. Fiber-optic refractive index sensor. Fluid of interesl is drawn by capillary action into a duct through a glass substrate. The effective path length varies in proportion with the refractive index. (Yazbak, Foxboro, Massachusetts)...

Mass of a molecule Mass of proton Mass of ion Concentration Avogadro constant Complex refraction index Optical refraction index Polarization... 

The linear susceptibility yy1 1 is related to optical refraction and absorption. The most common effects due to second-order susceptibility x(2) are frequency doubling x (-2co co, co) and the EO (Pockels) effect x(2)(- 0, co). The third-order susceptibility y 3) is responsible for such phenomena as frequency tripling and the Kerr effect. 

VI 17. Molar optical refraction R V- (n - 1) Index of light refraction n... 

The first basic law of optical refraction was formulated by Snellius (1618) and (independently) by Des-cartes (1637). It reads... 

Spectrochemical data (optical refraction and dispersion) were quoted in support of the structure of indoxazene.34,37,66,57 The subject has been well reviewed by Speroni.58... 

In contrast to molar polarisation calculated from optical refractivities, that calculated from relative permittivities observed at lower frequencies is by no means always independent of temperature. Actually, materials tend to fall into one of two classes. Those in one class show a relatively constant molar polarisation in accord with the simple Clausius-Mosotti relation, whilst the members of the other class, which contains materials with high relative permittivities, show a molar polarisation that decreases with increase in temperature. Debye recognised that permanent molecular dipole moments were responsible for the anomalous behaviour. From theories of chemical bonding we know that certain molecules which combine atoms of different electronegativity are partially ionic and consequently have a permanent dipole moment. Thus chlorine is highly electronegative and the carbon-chlorine... 

---