

īeing able to join optical fibers with low loss is important in fiber optic communication. Single-mode fibers are used for most communication links longer than 1,050 meters (3,440 ft).

Multi-mode fibers generally have a wider core diameter and are used for short-distance communication links and for applications where high power must be transmitted. Fibers that support many propagation paths or transverse modes are called multi-mode fibers, while those that support a single mode are called single-mode fibers (SMF). Light is kept in the core by the phenomenon of total internal reflection which causes the fiber to act as a waveguide. Optical fibers typically include a core surrounded by a transparent cladding material with a lower index of refraction. Specially designed fibers are also used for a variety of other applications, some of them being fiber optic sensors and fiber lasers. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Fibers are used instead of metal wires because signals travel along them with less loss in addition, fibers are immune to electromagnetic interference, a problem from which metal wires suffer. 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 transfer rates) than electrical cables. A bundle of optical fibers A TOSLINK fiber optic audio cable with red light shone in one endĪn optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass ( silica) or plastic to a diameter slightly thicker than that of a human hair.
