|
fiber optics, transmission of digitized messages or information by light pulses along hair-thin glass fibers. Each fiber is surrounded by a cladding having a high index of refractance so that the light is internally reflected and travels the length of the fiber without escaping. Cables of optical fibers can be made smaller and lighter than conventional cables using copper wires or coaxial tubes, yet they can carry much more information, making them useful for transmitting large amounts of data between computers and for carrying data-intensive television pictures or many simultaneous phone conversations. Optical fibers are immune to electromagnetic interference (from lightning, nearby electric motors, and similar sources) and to crosstalk from adjoining wires, and tapping into them is more easily detected. To keep a signal from deteriorating, optical fibers require fewer repeaters over a given distance than does copper wire. In addition to communications, optical fibers are beginning to be used in medical procedures, automobiles, and aircraft and are expected to have many other applications.
The Columbia Electronic Encyclopedia Copyright © 2009, Columbia
University Press.
Licensed from Columbia University Press. All rights reserved.
|
