fibre optics

fibre optics
Thin transparent fibres of glass or plastic that transmit light through their length by internal reflections, used for transmitting data, voice, and images.

Fibre-optic technology has virtually replaced copper wire in long-distance telephone lines and is used to link computers in local area networks, with digitized light pulses replacing the electric current formerly used for the signal. Telecommunication using fibre optics is usually conducted with infrared light. Fibre optics uses light in the visible wavelengths to transmit images directly, in various technical devices such as those developed for endoscopy.

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also spelled  fiber optics 
 the science of transmitting data, voice, and images by the passage of light through thin, transparent fibres. In telecommunications (telecommunications media), fibre optic technology has virtually replaced copper wire in long-distance telephone lines, and it is used to link computers (computer network) within local area networks. Fibre optics is also the basis of the fibrescopes used in examining internal parts of the body ( endoscopy) or inspecting the interiors of manufactured structural products.

      The basic medium of fibre optics is a hair-thin fibre that is sometimes made of plastic but most often of glass. A typical glass optical fibre has a diameter of 125 micrometres (μm), or 0.125 mm (0.005 inch). This is actually the diameter of the cladding, or outer reflecting layer; the core, or inner transmitting cylinder, may have a diameter as small as 10 μm. Through a process known as total internal reflection, light rays beamed into the fibre can propagate within the core for great distances with remarkably little attenuation, or reduction in intensity. The degree of attenuation over distance varies according to the wavelength of the light and to the composition of the fibre. When glass fibres of core/cladding design were introduced in the early 1950s, the presence of impurities restricted their employment to the short lengths sufficient for endoscopy. In 1966, electrical engineers K.C. Kao and G.A. Hockham, working in England, suggested using fibres for telecommunication, and within two decades silica glass fibres were being produced with sufficient purity that infrared light signals could travel through them for 100 km (60 miles) or more without having to be boosted by repeaters. Plastic fibres, usually made of polymethylmethacrylate, polystyrene, or polycarbonate, are cheaper to produce and more flexible than glass fibres, but their greater attenuation of light restricts their use to much shorter links within buildings or automobiles.

      Optical telecommunication is usually conducted with infrared (infrared radiation) light in the wavelength ranges of 0.8–0.9 μm or 1.3–1.6 μm—wavelengths that are efficiently generated by light-emitting diodes or semiconductor lasers and that suffer least attenuation in glass fibres. Fibrescope inspection in endoscopy or industry is conducted in the visible wavelengths, one bundle of fibres being used to illuminate the examined area with light and another bundle serving as an elongated lens for transmitting the image to the human eye or a video camera.

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Universalium. 2010.

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Look at other dictionaries:

  • fibre optics — fi‧bre op‧tics [ˌfaɪbər ˈɒptɪks ǁ ˈɑːp ] , fiber optics noun [uncountable] TELECOMMUNICATIONS the process of using very thin threads of glass or plastic to carry information in the form of light, especially on telephone lines fibre optic… …   Financial and business terms

  • fibre optics — n [U] the process of using very thin threads of glass or plastic to carry information in the form of light, especially on telephone lines ▪ fibre optic cables …   Dictionary of contemporary English

  • fibre optics — ► PLURAL NOUN (treated as sing. ) ▪ the use of thin flexible transparent fibres to transmit light signals, chiefly for telecommunications or for internal inspection of the body. DERIVATIVES fibre optic adjective …   English terms dictionary

  • fibre optics — noun the transmission of light signals via glass fibers • Syn: ↑fiber optics, ↑fiberoptics, ↑fibreoptics • Derivationally related forms: ↑fibreoptic (for: ↑fibreoptics), ↑fiberoptic …   Useful english dictionary

  • fibre optics — (The spelling fiber optics is also used in American English. The form fibre optic is used as a modifier.) 1) N UNCOUNT Fibre optics is the use of long thin threads of glass to carry information in the form of light. 2) ADJ: ADJ n Fibre optic… …   English dictionary

  • fibre optics — skaidulinė optika statusas T sritis fizika atitikmenys: angl. fiber optics; fibre optics vok. Faseroptik, f; Glasfaseroptik, f rus. волоконная оптика, f pranc. optique à fibres, f; optique des fibres, f …   Fizikos terminų žodynas

  • fibre optics — /faɪbər ˈɒptɪks/ (say fuybuhr optiks) noun 1. the process of passing light along bundles of very fine fibres by internal reflection, used in medicine to transmit images, and in communication (in the form of light pulses) to transmit information.… …  

  • fibre optics — plural noun [treated as sing.] the use of thin flexible transparent fibres to transmit light signals, chiefly for telecommunications or for internal inspection of the human body. Derivatives fibre optic adjective …   English new terms dictionary

  • fibre optics — noun (U) the process of using very thin threads of glass or plastic to carry information in the form of light, especially on telephone lines fibre optic adjective …   Longman dictionary of contemporary English

  • fibre optics — noun the transmission of light through fine flexible glass or plastic fibres, especially as a medium for communications networks …   Wiktionary

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