Optical systems Essay Example | Topics and Well Written Essays - 1750 words - 1

Optical systems - Essay Example These layers make them resistant to electrical and mechanical interferences. The refractive index feature makes plastic optics fibre multimode. The predecessor glass fibre come in single mode of step index or graded index profile. An illustrated diagram on how the two types guide the light is shown in appendix A figure 2. Three different light waves travel through the fiber. While the first one passes straight through the center of the core, the second mode passes at a steep angle and bounces back through the concept of total internal reflection. The third mode surpasses the critical angle, refracting into the cladding (www.fiberoptics4sale.com). The second mode is able to cover more distance than the first mode. These rays travel through a different paths, they thereby have different modes taking different time to reach. The variation so visible is termed as the dispersion, ultimately giving muddied signal at the receiving node. The output pulse varied against the input pulse. Increased index of refraction in the centre of the core leads to slowing down of the speed of some light rays, resulting in the rays to reach the receiving end at nearly about the same time, ultimately minimizing the dispersion and increase in the bandwidth (www.fiberoptics4sale.com).. Fibres work on concept of propagation of light, the light in a fiber-optic cable passes through the core of the fibre. At that time, if there are bends, it will result in reflection across the cladding .This concept is termed as total internal reflection. The part of light that skips through changes the direction on entering the outer layer due to refraction. Refraction occurs due to varying speeds and varying different refractive index (Wiley J,Ungear S (1990). Total internal reflection occurs (see appendix A figure 4 )when light passing through one material gets intact with a different