*#REDIRECT [[Electric light]] ▼
{{redirect|Light bulb}}
{{redirect|Electric lamp|the item of furniture|light fixture}}
{{refimprove|date=November 2014}}
[[File:Lelightbulbs.jpg|160px|thumb|Various compact fluorescent (CFL) lightbulbs]]
[[File:Gluehlampe 01 KMJ.jpg|160px|thumb|A clear glass 60 W Neolux light bulb]]
A '''lamp''' is a replaceable component such as an [[incandescent light bulb]], which is designed to produce [[light]] from [[electricity]].<ref>{{cite web |url=http://dictionary.reference.com/browse/lamp |title=Lamp |work=Dictionary.com |accessdate=Nov 9, 2014}}</ref> These components usually have a base of ceramic, metal, glass or plastic, which makes an electrical connection in the socket of a [[light fixture]]. This connection may be made with a screw-thread base, two metal pins, two metal caps or a bayonet cap.
==Types==
There are several types of lamp:
*[[Incandescent lamp]], a heated filament inside a glass envelope
**[[Halogen lamp]]s use a [[fused quartz]] envelope, filled with halogen gas
*[[LED lamp]], a solid-state lamp that uses [[light-emitting diode]]s (LEDs) as the source of light
*[[Laser diode lamp]]
*[[Arc lamp]]
**[[Xenon arc lamp]]
**Mercury-xenon arc lamp
**[[Ultra-high-performance lamp]], an ultra-high-pressure mercury-vapor arc lamp for use in [[Image projector|projector]]s
**[[Metal-halide lamp]]
*[[Gas-discharge lamp]], a light source that generates light by sending an [[electrical discharge]] through an [[ionized gas]]
**[[Fluorescent lamp]]
***[[Compact fluorescent lamp]], a fluorescent lamp designed to replace an incandescent lamp
**[[Neon lamp]]
**[[Mercury-vapor lamp]]
**[[Sodium-vapor lamp]]
**[[Sulfur lamp]]
**[[Electrodeless lamp]], a gas discharge lamp in which the power is transferred from outside the bulb to inside via electromagnetic fields
==Uses other than illumination==
Lamps can be used as heat sources, for example in [[Incubator (egg)|incubator]]s and toys such as the [[Easy-Bake Oven]].
Filament lamps have long been used as fast acting [[thermistor]]s in electronic circuits. The filaments are most likely made out of tungsten. Popular uses have included:
* Stabilisation of sine wave oscillators
* Protection of [[loudspeaker|tweeters]]
* [[Automatic volume control]] in telephones
==Lamp circuit symbols==
In [[circuit diagram]]s lamps usually are shown as symbols. There are two main types of symbols, these are:
{{Gallery
|lines=4
|File:Lamp symbol.svg|The cross in a circle, which usually represents a lamp as an indicator.
|File:Lamp symbol, old.svg|The semicircular dent in a circle, which usually represents a lamp as a source of light or illumination.
|File:LampSymbol.png|Another Electronic symbol for Lamp
}}
==See also==
* [[Light source]]
* [[Light tube]]
* [[List of light sources]]
==References==
{{Reflist}}
{{Artificial light sources}}
[[Category:Lighting]]
[[Category:Types of lamp]]
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