incandescent lamp

incandescent lamp
a lamp that emits light due to the glowing of a heated material, esp. the common device in which a tungsten filament enclosed within an evacuated glass bulb is rendered luminous by the passage of an electric current through it. Cf. fluorescent lamp.

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Any of various devices that produce light by heating a suitable material to a high temperature.

In an electric incandescent lamp, or lightbulb, a filament is enclosed in a glass shell that is either evacuated or filled with an inert gas. The filament gives off light when heated by an electric current. The first practical electric incandescent lamps were independently produced in the late 1870s by Joseph Swan and Thomas Alva Edison. Edison has received the major credit because of his development of the power lines and other equipment needed for a lighting system. Inefficient in comparison with fluorescent lamps and electric discharge lamps, incandescent lighting is today reserved mainly for domestic use. See also halogen lamp.

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      any of various devices that produce light by heating a suitable material to a high temperature. When any solid or gas is heated, commonly by combustion or resistance to an electric current, it gives off light (lightbulb) of a colour (spectral balance) characteristic of the material.

      In 1801 Sir Humphrey Davy (Davy, Sir Humphry, Baronet) demonstrated the incandescence of platinum strips heated in the open air by electricity; but the strips did not last long. Frederick de Moleyns of England was granted the first patent for an incandescent lamp in 1841; he used powdered charcoal heated between two platinum wires.

      The first practical incandescent lamps became possible after the invention of good vacuum pumps. The Englishman Sir Joseph Wilson Swan (Swan, Sir Joseph Wilson) in 1878 and the American inventor Thomas Alva Edison (Edison, Thomas Alva) in the following year independently produced lamps with carbon filaments in evacuated glass bulbs. Edison has received the major credit because of his development of the power lines and other equipment needed to establish the incandescent lamp in a practical lighting system.

      In 1911 the drawn tungsten filament was introduced; in 1913 filaments were coiled, and bulbs were filled with inert gas. Nitrogen alone was used first, and, later, nitrogen and argon in proportions varied to suit the wattage. These steps increased efficiency. Beginning in 1925, bulbs were “frosted” on the inside with hydrofluoric acid to provide a diffused light instead of the glaring brightness of the unconcealed filament.

      The carbon-arc lamp, a very bright electric lamp used for spotlights and in motion-picture projection, consists of two carbon electrodes with a high-current arc passing between them. The light comes from heating of the electrodes and from the ionized gases in the arc.

      Nonelectric incandescent lamps include the gas-mantle lamp. The mantle is a mesh bag of fabric impregnated with a solution of nitrates of cerium and one or more of the following metals: thorium, beryllium, aluminum, or magnesium. The mantle is fixed over an orifice carrying a flammable gas such as natural gas, coal gas, propane, or vaporized benzene or other fuel. When the gas is ignited, the mantle fabric burns away, leaving a brittle residual lattice of metal oxides. Light is produced when this lattice is heated to glowing by the gas combustion, although the mantle itself does not burn. Gas lamps may operate without mantles.

      The limelight is a very bright gas lamp, invented in 1825 and widely used for theatrical lighting until about 1900. It consists of a block of lime (calcium oxide) heated in an oxyhydrogen flame.

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Universalium. 2010.

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Look at other dictionaries:

  • Incandescent lamp — Incandescent In can*des cent, a. [L. incandecens, entis, p. pr. of incandescere to become warm or hot; pref. in in + candescere to become of a glittering whiteness, to become red hot, incho. fr. candere to be of a glittering whiteness: cf. F.… …   The Collaborative International Dictionary of English

  • incandescent lamp — n. a lamp in which the light is produced by a filament of conducting material contained in a vacuum and heated to incandescence by an electric current …   English World dictionary

  • incandescent lamp — noun electric lamp consisting of a transparent or translucent glass housing containing a wire filament (usually tungsten) that emits light when heated by electricity • Syn: ↑light bulb, ↑lightbulb, ↑bulb, ↑electric light, ↑electric light bulb •… …   Useful english dictionary

  • incandescent lamp — Tungsten lamp Tung sten lamp An electric glow lamp having filaments of metallic tungsten, and contained in a glass bulb which is evacuated or has an inert gas, to avoid oxidation of the tungsten; a common form of light bulb. Such lamps, owing to… …   The Collaborative International Dictionary of English

  • incandescent lamp — kaitinamoji lempa statusas T sritis fizika atitikmenys: angl. electric filament lamp; incandescent lamp vok. Glühfadenlampe, f; Glühlampe, f; Hitzdrahtlampe, f rus. лампа накаливания, f pranc. lampe à filament, f; lampe à incandescence, f …   Fizikos terminų žodynas

  • Incandescent lamp —   A glass enclosure in which light is produced when a tungsten filament is electrically heated so that it glows. Much of the energy is converted into heat; therefore, this class of lamp is a relatively inefficient source of light. Included in… …   Energy terms

  • incandescent lamp — in′candes′cent lamp′ n. elo elm a lamp in which a tungsten filament enclosed within an evacuated glass bulb glows as an electric current passes through it • Etymology: 1880–85 …   From formal English to slang

  • incandescent lamp — /ɪnkænˌdɛsənt ˈlæmp/ (say inkan.desuhnt lamp) noun a lamp whose light is due to the glowing of some material, as the common electric light globe which contains a filament rendered luminous by the passage of current through it …  

  • incandescent lamp — noun a lamp that creates radiant energy when its metallic filament is heated by an electric current …   Wiktionary

  • incandescent lamp — noun Date: 1881 lightbulb a …   New Collegiate Dictionary

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