Child Porn essays

Child Porn essays Fiber Optics Research Paper Fiber optics is a branch of optics concerning the transmission of light by means of optical fibers, which are thin strands of glass or other optically transparent materials. Optical fibers can be used to guide lightwhich is electromagnetic radiation in a certain frequency rangein much the same way that metal wave guides or coaxial cables can be used to guide lower-frequency electromagnetic radiation. An optical fiber is usually circular in cross section and consists of a core and cladding. An optical fiber for communication applications is typically between about 0.1 and 0.2mm (0.004 and 0.008 in) in diameter. In order that the light waves be guided by the fiber, the core must have a higher index of refraction than the cladding. One such fiber is called a step-index fiber because the index changes abruptly at the interface between the core and the cladding. An important variation of this structure is the graded-index fiber, so called because the index of refraction decreases smoothly outward from the In the step-index fiber, the light wave is guided by a process called total internal reflection. Only rays that have an angle of incidence at the core-cladding interface greater than the critical angle will be reflected back into the core and thus guided by the fiber. Some rays follow a longer path through the fiber than do others. Thus a pulse of energy entering the fiber undergoes dispersion. This effect limits the bandwidth of the fiber and reduces the amount of information it can transmit. This undesirable feature can be partly overcome by the use of graded-index fibers of proper design. Fiber optics is used in several areas of telecommunications. Advantages of optical fibers include their wide bandwidth, low attenuation, lightness, smal ...