A light fixture (US English), light fitting (UK English), or luminaire is an electrical lighting device containing one or more light sources, such as lamps, and all the accessory components required for its operation to provide illumination to the environment. All light fixtures have a fixture body and one or more lamps. The lamps may be in sockets for easy replacement—or, in the case of some
LED
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresp ...
fixtures, hard-wired in place.
Fixtures may also have a switch to control the light, either attached to the lamp body or attached to the power cable. Permanent light fixtures, such as dining room
chandelier
A chandelier () is an ornamental lighting device, typically with spreading branched supports for multiple lights, designed to be hung from the ceiling. Chandeliers are often ornate, and they were originally designed to hold candles, but now inca ...
s, may have no switch on the fixture itself, but rely on a wall switch.
Fixtures require an electrical connection to a power source, typically
AC mains
Alternating current (AC) is an electric current that periodically reverses direction and changes its magnitude continuously with time, in contrast to direct current (DC), which flows only in one direction. Alternating current is the form in w ...
power, but some run on battery power for camping or emergency lights. Permanent lighting fixtures are directly wired. Movable lamps have a plug and cord that plugs into a wall socket.
Light fixtures may also have other features, such as reflectors for directing the light, an
aperture
In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...
(with or without a
lens
A lens is a transmissive optical device that focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements'') ...
), an outer shell or housing for lamp alignment and protection, an
electrical ballast
An electrical ballast is a device placed in series with a load to limit the amount of electric current, current in an electrical network, electrical circuit.
A familiar and widely used example is the inductive ballast used in fluorescent lamp ...
or
power supply
A power supply is an electrical device that supplies electric power to an electrical load. The main purpose of a power supply is to convert electric current from a source to the correct voltage, electric current, current, and frequency to power ...
, and a shade to diffuse the light or direct it towards a workspace (e.g., a desk lamp). A wide variety of special light fixtures are created for use in the
automotive lighting
Automotive lighting is functional exterior lighting in vehicles. A motor vehicle has lighting and signaling devices mounted to or integrated into its front, rear, sides, and, in some cases, top. Various devices have the dual function of illumin ...
industry,
aerospace
Aerospace is a term used to collectively refer to the atmosphere and outer space. Aerospace activity is very diverse, with a multitude of commercial, industrial, and military applications. Aerospace engineering consists of aeronautics and astron ...
, marine and
medicine
Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...
sectors.
Portable light fixtures are often called ''lamps'', as in ''table lamp'' or ''desk lamp''. In
technical terminology
Jargon, or technical language, is the specialized terminology associated with a particular field or area of activity. Jargon is normally employed in a particular Context (language use), communicative context and may not be well understood outside ...
, the ''lamp'' is the light source, which, in casual terminology, is called the light bulb. Both the
International Electrotechnical Commission
The International Electrotechnical Commission (IEC; ) is an international standards organization that prepares and publishes international standards for all electrical, electronics, electronic and related technologies. IEC standards cover a va ...
Fixture manufacturing began soon after production of the
incandescent light bulb
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a #Filament, filament until it incandescence, glows. The filament is enclosed in a ...
. When practical uses of fluorescent lighting were realized after 1924, the three leading companies to produce various fixtures were Lightolier, Artcraft Fluorescent Lighting Corporation, and Globe Lighting in the United States.
Lampetter, 4 st - Hallwylska museet - 106934.tif, Neoclassical light fixture; mid-19th century; bronze; height: 18 cm; Hallwyl Museum (
Stockholm
Stockholm (; ) is the Capital city, capital and List of urban areas in Sweden by population, most populous city of Sweden, as well as the List of urban areas in the Nordic countries, largest urban area in the Nordic countries. Approximately ...
Budapest
Budapest is the Capital city, capital and List of cities and towns of Hungary, most populous city of Hungary. It is the List of cities in the European Union by population within city limits, tenth-largest city in the European Union by popul ...
,
Hungary
Hungary is a landlocked country in Central Europe. Spanning much of the Pannonian Basin, Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and ...
)
Lamp MET DP239606.jpg, Lamp; 1902–1918; lead and glass; 67.9 x 52.1 cm;
Metropolitan Museum of Art
The Metropolitan Museum of Art, colloquially referred to as the Met, is an Encyclopedic museum, encyclopedic art museum in New York City. By floor area, it is the List of largest museums, third-largest museum in the world and the List of larg ...
(New York City)
"Daffodil" lamp MET DP-16377-003.jpg, "Daffodil" lamp; 1904–1924; leaded opalescent glass and gilt bronze; height: 67.9 cm, diameter of shape: 51.4 cm; Metropolitan Museum of Art
HK_CWB_Park_Lane_basement_shop_IKEA_lighting_white_ceiling_lamps_Dec-2015_DSC.JPG, Various contemporary lamps for sale at an
IKEA
IKEA ( , ) is a Multinational corporation, multinational conglomerate (company), conglomerate founded in Sweden that designs and sells , household goods, and various related services.
IKEA is owned and operated by a series of not-for-profit an ...
store
Fixture types
Light fixtures are classified by how the fixture is installed, the light function or lamp type.
Free-standing or portable
* Table lamp fixtures, standard lamp fixtures, and office task light luminaires.
**
Balanced-arm lamp
A balanced-arm lamp, sometimes called a floating arm lamp, is a lamp with an adjustable folding arm which is constructed such that the force due to gravity is always counteracted by springs, regardless of the position of the arms of the lamp. Many ...
Nightlight
A nightlight is a small light fixture, usually electrical, placed for comfort or convenience in dark areas or areas that may become dark at certain times, such as at night or during an emergency. Small long-burning candles serving a similar fun ...
* Floor Lamp
** Torch lamp or torchières are floor lamps with an upward-facing shade. They provide general lighting to the rest of the room.
** Gooseneck lamp
* Bouillotte lamp: see
Bouillotte
Bouillotte is an 18th-century French gambling card game of the Revolution based on Brelan, very popular during the 19th century in France and again for some years from 1830. It was also popular in America. The game is regarded as one of the games ...
Fixed
* Ceiling Dome – the light source(s) are hidden behind a translucent dome typically made of glass, with some combination of frosting and surface texturing to diffuse the light. These can be flush-mount fixtures mounted into the ceiling, or semi-flush fixtures separated by a small distance (usually about 3–12").
** Open ceiling dome – the translucent dome is suspended a short distance below the ceiling by a mechanism that is hidden with the exception of a screw-knob or other device appearing on the outer dome face, and pulling this knob releases the dome.
** Enclosed ceiling dome – the translucent dome mates with a ring that is mounted flush with the ceiling.
*
Recessed light
A recessed light or downlight (also pot light in Canadian English, sometimes can light (for canister light) in American English) is a light fixture that is installed into a hollow opening in a ceiling. When installed it appears to have light sh ...
– the protective housing is concealed behind a ceiling or wall, leaving only the fixture itself exposed. The ceiling-mounted version is often called a downlight.
** "Cans" with a variety of lamps – this term is jargon for inexpensive downlighting products that are recessed into the ceiling, or sometimes for uplights placed on the floor. The name comes from the shape of the housing. The term "pot lights" is often used in Canada and parts of the US.
**
Cove light
Cove lighting is a form of indirect lighting built into ledges, recesses, or valances in a ceiling or high on the walls of a room. It directs light up towards the ceiling and down adjacent walls.http://www.lrc.rpi.edu/resources/publications/lpbh ...
– indirect lighting recessed into the ceiling in a long box against a wall.
** Troffer – recessed fluorescent light fixtures, usually rectangular in shape to fit into a drop ceiling grid.
* Surface-mounted light – the finished housing is exposed, not flush with the surface.
**
** Pendant light – suspended from the ceiling with a chain or pipe.
** Sconce – provide up or down lights; can be used to illuminate artwork, architectural details; commonly used in hallways or as an alternative to overhead lighting.
** Track lighting fixture – individual fixtures ("track heads") can be positioned anywhere along the track, which provides electric power.
** Under-cabinet light – mounted below kitchen wall cabinets.
** Display Case or Showcase light – shows merchandise on display within an enclosed case such as jewelry, grocery stores, and chain stores.
**
Ceiling fan
A ceiling fan is a mechanical fan, fan mounted on the ceiling of a room or space, usually electric power, electrically powered, that uses hub-mounted rotation, rotating blades to wikt:circulation, circulate air. They cool people effectively by ...
– may sometimes have a light, often referred to as a light kit mounted to it. Ceiling fans with built-in lights may eliminate the need for separate overhead light fixtures in a room, and light kits can also replace any ceiling-mounted light fixtures that were displaced by the installation of the ceiling fan.
** Emergency lighting or exit sign – connected to a battery backup or to an electric circuit that has emergency power if the mains power fails.
** High- and low-bay lighting – typically used for general lighting for industrial buildings and often
big-box store
A big-box store, a hyperstore, a supercenter, a superstore, or a megastore is a physically large retail establishment, usually part of a chain of stores. The term sometimes also refers, by extension, to the company that operates the store. The ...
s.
** Strip lights or Industrial lighting – often long lines of fluorescent lamps used in a
warehouse
A warehouse is a building for storing goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial parks on the rural–urban fringe, out ...
or
factory
A factory, manufacturing plant or production plant is an industrial facility, often a complex consisting of several buildings filled with machinery, where workers manufacture items or operate machines which process each item into another. Th ...
landscape lighting
Landscape lighting or garden lighting refers to the use of outdoor lighting, illumination of private gardens and public landscapes; for the enhancement and purposes of safety, nighttime aesthetics, accessibility, security, recreation and sports, ...
– used to illuminate walkways,
parking lot
A parking lot or car park (British English), also known as a car lot, is a cleared area intended for parking vehicles. The term usually refers to an area dedicated only for parking, with a durable or semi-durable surface. In most jurisdi ...
s,
roadway
A carriageway (British English) or roadway (North American English) is a width of road on which a vehicle is not restricted by any physical barriers or separation to move laterally. A carriageway generally consists of a number of traffic lane ...
s, building exteriors and architectural details,
garden
A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate bot ...
s, and
park
A park is an area of natural, semi-natural or planted space set aside for human enjoyment and recreation or for the protection of wildlife or natural habitats. Urban parks are urban green space, green spaces set aside for recreation inside t ...
s. Outdoor light fixtures can also include forms similar to indoor lighting, such as pendants, flush or close-to-ceiling light fixtures, wall-mounted lanterns and dome lights.
** High-mast, usually pole – or
stanchion
A stanchion () is a sturdy upright fixture that provides support for some other object. It can be a permanent fixture.
Types
In architecture, stanchions are the upright iron bars in windows that pass through the eyes of the saddle bars or horiz ...
-mounted – for landscape, roadways, and parking lots.
**
Bollard
A bollard is a sturdy, short, vertical post. The term originally referred to a post on a ship or quay used principally for mooring boats. In modern usage, it also refers to posts installed to control road traffic and posts designed to pre ...
– a type of architectural outdoor lighting that is a short, upright ground-mounted unit typically used to provide cutoff type illumination for egress lighting, to light walkways, steps, or other pathways.
** Solar lamp
**
Street light
A street light, light pole, lamp pole, lamppost, streetlamp, light standard, or lamp standard is a raised source of light on the edge of a road or path. Similar lights may be found on a railway platform. When urban electric power distribution b ...
* Accent light – any directional light that highlights an object or attracts attention to a particular area.
*
Background light
A background light is used to illuminate the background area of a set. The background light will also provide separation between the subject and the background. Many lighting setups follow a three-point lighting or four-point lighting setup. F ...
– for use in
video production
Video production is the process of producing video content. It is the equivalent of filmmaking, but with video recorded either as analog signals on videotape, digitally in video tape or as computer files stored on optical discs, hard drives, SSDs, ...
.
*
Blacklight
A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ( UV-A) ultraviolet light and very little visible light. One type of lamp has a violet filter material, either on the bulb or in a se ...
*
Christmas lights
Christmas lights (also known as fairy lights, festive lights or string lights) are lights often used for decoration in celebration of Christmas, often on display throughout the Christmas season including Advent and Christmastide. The custom ...
– also called fairy lights or twinkle lights and are often used at
Christmas
Christmas is an annual festival commemorating Nativity of Jesus, the birth of Jesus Christ, observed primarily on December 25 as a Religion, religious and Culture, cultural celebration among billions of people Observance of Christmas by coun ...
and other holidays for decoration.
* Dock light - provides light for boating safety. Typically affixed atop pilings or directly upon the dock floor itself.
* Emergency light – provides minimal light to a building during a power outage.
* Exit sign
* Flood light
* Safelight (for use in a
darkroom
A darkroom is used to process photographic film, make Photographic printing, prints and carry out other associated tasks. It is a room that can be made completely dark to allow the processing of light-sensitive photographic materials, including ...
coal mine
Coal mining is the process of resource extraction, extracting coal from the ground or from a mine. Coal is valued for its Energy value of coal, energy content and since the 1880s has been widely used to Electricity generation, generate electr ...
s)
*
Searchlight
A searchlight (or spotlight) is an apparatus that combines an extremely luminosity, bright source (traditionally a carbon arc lamp) with a mirrored parabolic reflector to project a powerful beam of light of approximately parallel rays in a part ...
(for military and advertising use)
*
Security lighting In the field of physical security, security lighting is lighting that intended to deter or detect intrusions or other criminal activity occurring on a property or site. It can also be used to increase a feeling of safety. Lighting is integral to cri ...
* Step light
*
Strobe light
A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope. The word originated from the Ancient Greek ('), meaning ...
Traffic light
Traffic lights, traffic signals, or stoplights – also known as robots in South Africa, Zambia, and Namibia – are signaling devices positioned at intersection (road), road intersections, pedestrian crossings, and other locations in order t ...
* Theatrical
**
Stage lighting instrument
Stage lighting instruments (lanterns, or luminaires in Europe) are used in stage lighting to illuminate theatrical productions, concerts, and other performances taking place in live performance venues. They are also used to light television st ...
Arc lamp
An arc lamp or arc light is a lamp that produces light by an electric arc (also called a voltaic arc).
The carbon arc light, which consists of an arc between carbon electrodes in air, invented by Humphry Davy in the first decade of the 1800s, ...
s
:
Xenon arc lamp
A xenon arc lamp is a highly specialized type of gas discharge lamp, an electric light that produces light by passing electricity through ionized xenon gas at high pressure. It produces a bright white light to simulate sunlight, with applications ...
,
Yablochkov candle
A Yablochkov candle (sometimes electric candle or Jablochkoff candle) is a type of electric carbon arc lamp, invented in 1876 by the Russian electrical engineer Pavel Yablochkov.
Design
A Yablochkov candle consists of a sandwich of two electrode ...
*
Fluorescent
Fluorescence is one of two kinds of photoluminescence, the emission of light by a substance that has absorbed light or other electromagnetic radiation. When exposed to ultraviolet radiation, many substances will glow (fluoresce) with color ...
:
Fluorescent lamp
A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, to produce ultraviolet and make a phosphor ...
,
compact fluorescent lamp
A compact fluorescent lamp (CFL), also called compact fluorescent light, energy-saving light and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent light bulb; some types fit into light fixtures designed for incan ...
blacklight
A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ( UV-A) ultraviolet light and very little visible light. One type of lamp has a violet filter material, either on the bulb or in a se ...
carbide lamp
A carbide lamp or acetylene gas lamp is a simple lamp that produces and burns acetylene (C2H2), which is created by the reaction of calcium carbide (CaC2) with water (H2O).
Acetylene gas lamps were used to illuminate buildings, as lighthouse beac ...
,
gas lighting
Gas lighting is the production of artificial light from combustion of a fuel gas such as methane, propane, butane, acetylene, ethylene, hydrogen, carbon monoxide, coal gas (town gas) or natural gas. The light is produced either directly by ...
oil lamp
An oil lamp is a lamp used to produce light continuously for a period of time using an oil-based fuel source. The use of oil lamps began thousands of years ago and continues to this day, although their use is less common in modern times. The ...
torch
A torch is a stick with combustible material at one end which can be used as a light source or to set something on fire. Torches have been used throughout history and are still used in processions, symbolic and religious events, and in juggl ...
,
candle
A candle is an ignitable candle wick, wick embedded in wax, or another flammable solid substance such as tallow, that provides light, and in some cases, a Aroma compound, fragrance. A candle can also provide heat or a method of keeping time. ...
,
Limelight
Limelight (also known as Drummond light or calcium light)James R. Smith (2004). ''San Francisco's Lost Landmarks'', Quill Driver Books. is a non-electric type of stage lighting that was once used in theatres and music halls. An intense illum ...
Davy lamp
The Davy lamp is a safety lamp used in flammable atmospheres, invented in 1815 by Sir Humphry Davy.Geordie lamp
*
Gas-discharge lamp
Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionization, ionized gas, a plasma (physics), plasma.
Typically, such lamps use a
noble gas (argon, neon, krypton, and x ...
and
high-intensity discharge lamp
High-intensity discharge lamps (HID lamps) are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc ...
Neon sign
In the signage industry, neon signs are electric signs lighted by long luminous gas-discharge tubes that contain rarefied neon or other gases. They are the most common use for neon lighting, which was first demonstrated in a modern form in Decem ...
*
Incandescent lamp
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a filament until it glows. The filament is enclosed in a glass bulb that is eith ...
limelight
Limelight (also known as Drummond light or calcium light)James R. Smith (2004). ''San Francisco's Lost Landmarks'', Quill Driver Books. is a non-electric type of stage lighting that was once used in theatres and music halls. An intense illum ...
Mazda (light bulb)
Mazda was a trademarked name registered by General Electric (GE) in 1909 for incandescent light bulbs. The name was used from 1909 to 1945 in the United States by GE and Westinghouse Electric (1886), Westinghouse. Mazda brand light bulbs were mad ...
Halogen
The halogens () are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors would ...
– special class of incandescent lamps
*Nuclear:
self-powered lighting
Tritium radioluminescence is the use of gaseous tritium, a radioactive isotope of hydrogen, to create visible light. Tritium emits electrons through beta decay and, when they interact with a phosphor material, light is emitted through the proc ...
LED
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresp ...
There are various types of devices used to manage the amount of light used:
* 3-way 2-circuit switch
* Dimmer (this allows the user to make a light brighter or dimmer, typically using a rotary dial)
* Light switch (often part of the light socket or
power cord
A power cord, line cord, or mains cable is an electrical cable that temporarily connects an electrical appliance, appliance to the mains electricity supply via a wall socket or extension cord. The terms are generally used for cables using a AC p ...
Motion detector
A motion detector is an electrical device that utilizes a sensor to detect nearby motion (motion detection). Such a device is often integrated as a Electronic component, component of a system that automatically performs a task or Security alarm, ...
*
Timer
A timer or countdown timer is a type of clock that starts from a specified time duration and stops upon reaching 00:00. It can also usually be stopped manually before the whole duration has elapsed. An example of a simple timer is an hourglass ...
*
Touch
The somatosensory system, or somatic sensory system is a subset of the sensory nervous system. The main functions of the somatosensory system are the perception of external stimuli, the perception of internal stimuli, and the regulation of bo ...
Flashlight
A flashlight (US English) or electric torch (Commonwealth English), usually shortened to torch, is a portable hand-held electric lamp. Formerly, the light source typically was a miniature incandescent light bulb, but these have been displaced ...
Lantern
A lantern is a source of lighting, often portable. It typically features a protective enclosure for the light sourcehistorically usually a candle, a oil lamp, wick in oil, or a thermoluminescence, thermoluminescent Gas mantle, mesh, and often a ...
Lightbulb socket
A lightbulb socket, lightbulb holder, light socket, lamp socket or lamp holder is a device which mechanically supports and provides electrical connections for a compatible electric Lamp (electrical component), lamp base. Sockets allow lamps to ...
Light pollution
Light pollution is the presence of any unwanted, inappropriate, or excessive artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting sources, during the ...
References
External links
* ''Look at the Chart and Pick Out the Reflector You Need'', ''
Popular Science
Popular science (also called pop-science or popsci) is an interpretation of science intended for a general audience. While science journalism focuses on recent scientific developments, popular science is more broad ranging. It may be written ...