Fiber is a kind of message transmitted from one end to the otherend 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. Mostfi ber must be covered by several layers of protection structurebefore use, the coated cable is called " cable". To protect thestructure fiber layer can prevent the environment of fiberdamage, such as water, fire, electric cable and so on. Foroptical fiber, buffer layer and cladding. Similar to opticalfi ber and coaxial cable, but no mesh shielding layer. The centeris the core of light transmission glass. In multimode fiber,the core diameter is 15mm '50mm, and the thi ckness of human hairis roughly equal. The single-mode fiber core diameter of 8mm 10mm. The core is surrounded by a layer of glass envelopeof low refractive index than the core, in order to maintain inthe core optical fiber. Outside is a thin layer of plasticjacket to protect the envelope. The fiber is usually tied intobundles, outside shell protection. The core is usually doubleconcentric cylinders cross-sectional area made of quartz glassis very small, it is brittle, easily broken, therefore requireadditional protective layer.
