Standard optical fibers are made by first constructing a large-diameter preform with a carefully controlled refractive index profile, and then pulling the preform to form the long, thin optical fiber.OverviewAn optical fiber, or optical fibre, is a flexible or plastic that can transmit from one end to the other. Such fibers are widely used in, where they permit transmission over longer distances a. and first demonstrated the guiding of light by refraction, the principle that makes fiber optics possible, in in the early 1840s. included a demonstration of it in his publi. Optical fiber is used as a medium for and because it is flexible and can be bundled as cables. It is especially advantageous for long-distance communications, because propagates.