Which material is used to prepare optical fiber as a transmission media?

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RRB ALP CBT 2 Electronic Mechanic Previous Paper: Held on 23 Jan 2019 Shift 1

Answer 1

Optical fibers:

An optical fiber is a transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair.
Each fiber consists of a core and cladding.
Optical fibers are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data rates) than wire cables.
Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide.

Advantages and comparison of Plastic and Glass fiber Optics are as follows:

Plastic fibers allow less signal attenuation than glass fibers. Attenuation is caused by the inherent material properties of the fiber optic, such as absorption, scattering, and impurities.
Plastic fibers are more flexible, and also survive well under repeated flexing.
Most glass fiber optic assemblies are very rugged and perform reliably in extreme temperatures.
Glass fiber optic assemblies can transmit both visible and infrared light, where plastic fiber optics can only transmit visible light.
Glass fibers can often be used in corrosive and wet environments.