Optical fibers lanthanum

Relatively smaller amounts of very high purity A1F. are used ia ultra low loss optical fiber—duotide glass compositions, the most common of which is ZBLAN containing tirconium, barium, lanthanum, aluminum, and sodium (see Fiber optics). High purity A1F. is also used ia the manufacture of aluminum siUcate fiber and ia ceramics for electrical resistors (see Ceramics AS electrical materials Refractory fibers). 

Lanthanum metal has relatively few uses. Some of its compounds however, are used in lamps, color television sets, cigarette lighters, optical fibers, and hybrid cars. 

A newer application of lanthanum glass is in making optical fibers. An optical fiber is a wire-like material made of glass. It carries light in the same way a copper wire carries electricity. Optical fibers have become popular methods for carrying audio, video, and digital messages. In many cases, optical fibers have replaced copper wires for this purpose. 

In 1974, a team of French researchers invented a product called ZBLAN. It is made of zirconium, barium, lanthanum, aluminum, and sodium. ( ZBLAN comes from the first letters of each element s symbol.) Scientists have found that ZBLAN is 100 times better at carrying messages than traditional optical fibers. 

A variety of fiber optic thermometry systems using fluorescence sensors have been discussed or become available over the past years. Most of the earliest systems are based on the temperature-dependent fluorescence intensity of appropriate materials. One such example of an early commercial system is the Luxtron model 1000, shown in Figure 11.2, which utilized europium-activated lanthanum and gadolinium... 

Highly pure lanthanum oxide is used to make optical glass of high refractive index for camera lenses. It also is used to make glass fibers. The oxide also is used to improve thermal and electrical properties of barium and strontium titanates. Other applications are in glass polishes carbon arc electrodes fluorescent type phosphors and as a diluent for nuclear fuels. In such apph-cations, lanthinum oxide is usually combined with other rare earth oxides. 

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