Optical fibers are very thin fibers of transparent material of very high clarity that are used for transmitting light light along it. These fibres are generally made of different type of glass but can also be made of plastics. These fibers are used these days transmission of data used in information and communication technology. Fiber optic cables are capable of transmitting data over much longer distances and at very high bandwidth rates. Optic fibers are also used for carrying light when the light need to travel in curved path around bends.
The basic requirements of the material of optic fiber cable is its clarity so that it allows light to pass through without blocking it by impurities contained in the material The second requirement is of the refractive index that ensures that a good amount of the light entering the fibre is contained within it by the process of total internal refraction.
Glass optical fibers are usually made of silica glass but in some cases other types of glass are also used or transmission of light of longer wavelengths. Plastic is generally used for fibers with diameter of 0.5 mm or more.
Optical fibers are long, flexible cylinders, with diameter 10-100μm, in which light rays propagate through multiple total internal reflections on surface of the fibers' side. There are gradient optical fibers, characterized by the fact that refractive index is maximum in the center of the fiber, gradually decreasing toward its periphery, so that total reflection of light is more complicated than in case of a single optical fiber.
Regardless of the fields that they are used, optic fibers are light guides used for sharing information with less energy lost, from one place to another place.
No matter of the composition chosen, the dielectric material used to obtain optical fibers must answer to the following requirements:
- to have better transparency at the wavelength of the light signal used;
- to possess chemical stability in time;
- to be easily processed in all stages of technological process.