The initial studies in optical networking were undertaken in the 1970's. It was discovered that a glass fiber encased in an opaque sheath was capable of transmitting data at a speed higher than that of light.
The optical fiber is thus one of the greatest technological advances in the area of cabling since it does away with all the disadvantages of electric cables such as power, impedance etc. Its purpose is to transmit light whose source is either a laser or an LED (light emitting diode).
[...] For higher temperatures, there are special coatings that shed some additional mitigation. Finally, the fiber is subjected to a test of strength (screen test), which eliminates weak segments, and is finally wound on a spool for easy transportation. Analysis of the process of manufacturing the optical fiber As mentioned earlier, the pre-form is manufactured using different processes, which differ mainly in the process of heating the silica. MVCD Method (Modified Chemical Vapor Deposition) The deposit is internal and is done in concentric layers, obtained by oxidation inside a quartz tube. [...]
[...] The advantage of the method lies in the absence of the tube, but it is necessary to drain the pipe before the test. This method is mainly used for step-index fibers. After passing one of these stages of pre-form manufacturing, the optical fiber is made by stretching the pre-form without contact, by merging its end in an induction furnace filled with inert gas. The diameter of the fiber is measured and kept constant by controlling the velocity of circulation by the capstan which is located [...]
[...] The layer of pure silica obtained by this process has a refractive index of The heart When the sheath has reached the desired thickness, the heart of the fiber is made in the remaining space. The heart is composed of silica. However, it has a higher refractive index than that of the sheath. To obtain this quality, we must add a substance, called a dopant which is usually a low concentration of germanium chloride (GeCl and gas precursors. Oxidation of this gas produces germanium oxide by the following reaction: GeCl 4 + O 2 GeO 2 + 2Cl 2 Pure germanium oxide has a refractive index of When a C concentration of GeO 2 is added to silica, the glass obtained has a refractive index: n = 2 SiO 2 + C 2 GeO 2 - SiO 2 n 1 / 2 Thus, to obtain glass with a refractive index of a concentration of GeO 2 is required. [...]
[...] The process of manufacturing optical fibers: The performance of optical fibers depends largely on the manufacturing processes and materials used. The methods which were used for manufacturing optical fibers for traditional applications did not provide the level of purity required for telecommunications. It is manufactured synthetically in two steps: The manufacture of a pre-form, cylindrical rod about 1 m long and several centimeters in diameter, homothetic to the future fiber. Drawing the pre-form into the several kilometer long fibers. Glasses with high silica content are used for the production of optical fibers. [...]
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