光缆知识(国外英文资料).doc

光缆知识(国外英文资料) Fiber is a kind of message transmitted from one end to the other end of the media. It is a glass or plastic fiber as the transmission medium to make the messages through. Usually fiber and cable two words would be confused. Most fiber must be covered by several layers of protection structure before use, the coated cable is called cable. To protect the structure fiber layer can prevent the environment of fiber damage, such as water, fire, electric cable and so on. For optical fiber, buffer layer and cladding. Similar to optical fiber and coaxial cable, but no mesh shielding layer. The center is the core of light transmission glass. In multimode fiber, the core diameter is 15mm~50mm, and the thickness of human hair is roughly equal. The single-mode fiber core diameter of 8mm~10mm. The core is surrounded by a layer of glass envelope of low refractive index than the core, in order to maintain in the core optical fiber. Outside is a thin layer of plastic jacket to protect the envelope. The fiber is usually tied into bundles, outside shell protection. The core is usually double concentric cylinders cross-sectional area made of quartz glass is very small, it is brittle, easily broken, therefore require additional protective layer. The characteristics of optical fiber The optical fiber is a transmission medium, it can be like a general copper wire, transmission of telephone calls or computer data, the difference is that the optical fiber is transmitted light signal instead of signal. Therefore, optical fiber has many unique advantages. Such as: Broadband wide. Low loss electromagnetic radiation shielding. Light weight. Safety. Privacy. Optical fiber system You may know that any communication transmission includes: encoding, transmission, decoding, of course, the transmission process of optical fiber systems are roughly the same. The electronic signal input, the signal transmitter through digital encoding, a light signal light through the optical fiber as the m