Unit 7 Assignment 1. Refraction, Reflection and Optics
The prism is an example of refraction. It also shows that the extent of refraction of light depends on the color. In a prism, light is refracted as it enters and as it leaves the prism and the light waves of different colors change directions by different amounts so that when they exit the colors are seen at different angles.
Reflection is the turning back of the light from the surface it hits. Incoming and reflected lights have same angle with the surface. If the surface reflects most of the light then we call such surfaces as mirrors. Examine the given pictures below. They show regular and diffuse reflection of light from given surfaces.
Polarization Mode Dispersion is caused due to different velocity for each polarization mode because of lack of perfect symmetric fibers. Extrinsic absorption It is caused due to the impurities in the material. Metal impurities such as iron nickel and chromium are introduced in the fiber during fabrication. It also occurs due to the presence of hydroxyl ions due to presence of water vapour.Extrinsic absorption can be reduced by glass refining techniques such as vapor oxidation and by using a glass fiber called dry fiber which reduces the OH ion concentration. Intrinsic absorption It is caused by basic fiber material properties. If an optical fiber is absolutely pure with no impurities or imperfections then absorption is intrinsic. The causes of intrinsic absorption are material and electron absorption. Scattering loss:-Scattering loss is a general physical process where some form of radiation is forced to deviate from a straight line by one or more localised medium through which they pass. Diffuse reflections are reflections that undergo scattering. Scattering losses are caused by interaction of light with density fluctuations in the fibres.The propagation of light through the fiber core is in...