Light fixture
Encyclopedia
A light fixture, light fitting, or luminaire is an electrical device used to create artificial light and/or illumination, by use of an electric lamp
Lamp (electrical component)
A lamp is a replaceable component such as an incandescent light bulb, which is designed to produce light from electricity. 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...

. All light fixtures have a fixture body, a light socket to hold the lamp and allow for its replacement—which may also have a switch to operate the fixture, and also require an electrical connection
Electrical connection
An electrical connection between discrete points allows the flow of electrons . A pair of connections is needed for a circuit.Between points with a low voltage difference, direct current can be controlled by a switch...

 to a power source, often by using electrical connectors (e.g. plugs) with portable fixtures. Light fixtures may also have other features, such as reflector
Mirror
A mirror is an object that reflects light or sound in a way that preserves much of its original quality prior to its contact with the mirror. Some mirrors also filter out some wavelengths, while preserving other wavelengths in the reflection...

s for directing the light, an aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...

 (with or without a lens
Lens (optics)
A lens is an optical device with perfect or approximate axial symmetry which transmits and refracts light, converging or diverging the beam. A simple lens consists of a single optical element...

), an outer shell or housing for lamp alignment and protection, and an electrical ballast
Electrical ballast
An electrical ballast is a device intended to limit the amount of current in an electric circuit. A familiar and widely used example is the inductive ballast used in fluorescent lamps, to limit the current through the tube, which would otherwise rise to destructive levels due to the tube's...

 and/or power supply
Power supply
A power supply is a device that supplies electrical energy to one or more electric loads. The term is most commonly applied to devices that convert one form of electrical energy to another, though it may also refer to devices that convert another form of energy to electrical energy...

. A wide variety of special light fixtures are created for use in the automotive lighting
Automotive lighting
The lighting system of a motor vehicle consists of lighting and signalling devices mounted or integrated to the front, sides, rear, and in some cases the top of the motor vehicle...

 industry, aerospace
Aerospace
Aerospace comprises the atmosphere of Earth and surrounding space. Typically the term is used to refer to the industry that researches, designs, manufactures, operates, and maintains vehicles moving through air and space...

, marine and medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....

.

The use of the word "lamp" to describe light fixtures is common slang for an all-in-one luminary unit, usually portable
Portable
Portable may refer to:* Portable building, a manufactured structure that is built off site and moved in upon completion of site and utility work...

 "fixtures" such as a table lamp or desk lamp (in contrast to a true fixture, which is fixed in place with screws or some other semi-permanent attachment). In technical terminology
Technical terminology
Technical terminology is the specialized vocabulary of any field, not just technical fields. The same is true of the synonyms technical terms, terms of art, shop talk and words of art, which do not necessarily refer to technology or art...

, a lamp is the light source, what is typically called the light bulb. (See Lamp (electrical component)
Lamp (electrical component)
A lamp is a replaceable component such as an incandescent light bulb, which is designed to produce light from electricity. 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...

.)

Light fixtures are classified by how the fixture is installed, the light function or lamp type.

Light fixture is US usage; in British English it is called a light fitting. However, luminaire is the International Electrotechnical Commission
International Electrotechnical Commission
The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...

 (IEC) terminology for technical use.

History

  • Fixture manufacturing began soon after production of the incandescent light bulb. When practical uses of fluorescent lighting were realized after 1939, the three (3) leading companies to produce various fixtures were Lightolier
    Lightolier
    Lightolier is a company that manufactures and sells a wide array of lighting fixtures. It was founded in 1904 by Bernhard Blitzer under the name of New York Gas and Appliance Co. When electric lighting started to be more widely accepted, the name was changed to Lightolier, a contraction of the...

    , Artcraft Fluorescent Lighting Corporation
    Artcraft Fluorescent Lighting Corporation
    Artcraft Fluorescent Lighting Corporation was one of the three most influential business forces in fluorescent lighting fixture development and production in the United States from the commercial introduction of the fluorescent lamp at the 1939 World's Fair....

    , and Globe Lighting in the United States.

Free-standing or portable

  • Table lamp fixtures, standard lamp fixtures, and office task light luminaires.
    • Balanced-arm lamp is a spot light with an adjustable arm such as anglepoise
      Anglepoise lamp
      The Anglepoise lamp is a balanced-arm lamp designed in 1932 by British designer George Carwardine.-History and development:Carwardine was a car designer and was, at the time he invented the Anglepoise lamp, a freelance design consultant specialising in vehicle suspension systems...

       or Luxo L1.
    • Gooseneck lamp
      Gooseneck lamp
      A Gooseneck lamp is a type of light fixture in which a lamp is attached to a flexible, adjustable shaft to allow the user to position the light source without moving the fixture or item to be illuminated. Gooseneck lamps are often used to position a light for reading, or in industry, to provide...

    • Nightlight
      Nightlight
      A nightlight is a small light fixture, often electrical, placed for comfort or convenience in dark areas or areas that become dark at certain times, such as in an emergency...


Fixed

  • Recessed light
    Recessed light
    A recessed light or downlight is a light fixture that is installed into a hollow opening in a ceiling...

     — 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.
    • Troffer light — recessed fluorescent lights (the word comes from the combination of trough and coffer).
    • Cove light — recessed into the ceiling in a long box against a wall.
    • Torch lamp, torchière
      Torchiere
      A torchiere , or torch lamp, is a lamp with a tall stand of wood or metal. Originally, torchieres were candelabra, usually with two or three lights...

      , or floor lamp.

  • Surface-mounted light — the finished housing is exposed, not flush with surface
    • Chandelier
      Chandelier
      A chandelier is a branched decorative ceiling-mounted light fixture with two or more arms bearing lights. Chandeliers are often ornate, containing dozens of lamps and complex arrays of glass or crystal prisms to illuminate a room with refracted light...

    • Pendant light
      Pendant light
      A pendant light, sometimes called a drop or suspender, is a lone light fixture that hangs from the ceiling usually suspended by a cord, chain, or metal rod. Pendant lights are often used in multiples, hung in a straight line over kitchen countertops and dinette sets or sometimes in bathrooms. ...

       — suspended from the ceiling with a chain or pipe
    • Sconce
      Sconce (light fixture)
      A sconce is a type of light fixture affixed to a wall in such a way that it uses only the wall for support, and the light is usually directed upwards. It does not have a base on the ground...

       — provide up or down lights; can be used to illuminate artwork, architectural details; commonly used in hallways and/or as an alternative to overhead lighting.
    • Track lighting
      Track lighting
      Track lighting is a method of lighting where light fixtures are attached anywhere on a continuous track device which contains electrical conductors. This is as opposed to the routing of electrical wiring to individual light positions. Tracks can be mounted to ceilings or walls, lengthwise down...

       fixture — individual fixtures ("track heads") can be positioned anywhere along the track, which provides electric power.
    • Under-cabinet light — mounted below kitchen wall cabinets
    • Emergency lighting or exit
      Exit
      Exit may refer to:* Door* Portal , an opening in the walls of a structure* Emergency exit* Overwing exit, a type of emergency exit on an airplane* Exit ramp, a feature of a road interchange-Computing:...

       light — connected to a battery backup or to an electric circuit that has emergency power
      Emergency power system
      Emergency power systems are a type of system, which may include lighting, generators, fuel cells and other apparatus, to provide backup power resources in a crisis or when regular systems fail. They find uses in a wide variety of settings from residential homes to hospitals, scientific...

       if the mains power fails
    • High- and low-bay lighting — typically used for general lighting for industrial buildings and often big-box store
      Big-box store
      A big-box store is a physically large retail establishment, usually part of a chain. The term sometimes also refers, by extension, to the company that operates the store...

      s
    • Strip lights or industrial lighting — often long lines of fluorescent lamps used in a warehouse
      Warehouse
      A warehouse is a commercial building for storage of goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial areas of cities and towns. They usually have loading docks to load and unload...

       or factory
      Factory
      A factory or manufacturing plant is an industrial building where laborers manufacture goods or supervise machines processing one product into another. Most modern factories have large warehouses or warehouse-like facilities that contain heavy equipment used for assembly line production...



  • Outdoor lighting and landscape lighting — used to illuminate walkways, parking lot
    Parking lot
    A parking lot , also known as car lot, is a cleared area that is intended for parking vehicles. Usually, the term refers to a dedicated area that has been provided with a durable or semi-durable surface....

    s, roadways, building exteriors and architectural details, garden
    Garden
    A garden is a planned space, usually outdoors, set aside for the display, cultivation, and enjoyment of plants and other forms of nature. The garden can incorporate both natural and man-made materials. The most common form today is known as a residential garden, but the term garden has...

    s, and park
    Park
    A park is a protected area, in its natural or semi-natural state, or planted, and set aside for human recreation and enjoyment, or for the protection of wildlife or natural habitats. It may consist of rocks, soil, water, flora and fauna and grass areas. Many parks are legally protected by...

    s, .
    • Pole
      Pole
      -General:*Poles, people originating from inbitating or inhabiting the country of Poland*Pole -Fictional:*Jill Pole, a fictional character from C. S...

      - or stanchion
      Stanchion
      A stanchion is an upright bar or post, often providing support for some other object.* An architectural term applied to the upright iron bars in windows that pass through the eyes of the saddle bars or horizontal irons to steady the leadlight. A stanchion is an upright bar or post, often...

      -mounted — for landscape, roadways, and parking lots
    • Pathway lighting — typically mounted in the ground at low levels for illuminating walkways
    • Bollard
      Bollard
      A bollard is a short vertical post. Originally it meant a post used on a ship or a quay, principally for mooring. The word now also describes a variety of structures to control or direct road traffic, such as posts arranged in a line to obstruct the passage of motor vehicles...

       — 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.
    • Sign light — used to light building signs or walls
    • Street light pole
    • Street light
      Street light
      A street light, lamppost, street lamp, light standard, or lamp standard is a raised source of light on the edge of a road or walkway, which is turned on or lit at a certain time every night. Modern lamps may also have light-sensitive photocells to turn them on at dusk, off at dawn, or activate...

    • Yard light
      Yard light
      A yard light or garden lantern is a free standing exterior light fixture in gardens and landscaped settings. They are usually illuminated by electricity, but occasionally natural gas., usually placed near an outdoor path or driveway to provide visibility in dark areas or areas that become dark at...

    • Garden lights - line and low voltage, and solar.
    • Solar lamp
      Solar lamp
      A solar lamp is a portable light fixture composed of a LED lamp, a photovoltaic solar panel, and a rechargeable battery.Outdoor lamps are used for lawn and garden decorations. Indoor solar lamps are also used for general illumination .Solar lights are used for decoration, and come in a wide variety...


Special-purpose lights

  • Accent light — Any directional light which highlights an object or attracts attention to a particular area
  • Background light
    Background light
    The 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. In the standard 4-point lighting setup, the background light is placed last and is usually placed directly behind the subject and...

     — for use in video production
    Video production
    Video production is videography, the process of capturing moving images on electronic media even streaming media. The term includes methods of production and post-production...

  • Blacklight
  • Flood light
  • Safelight
    Safelight
    A safelight is a light source suitable for use in a photographic darkroom. It provides illumination only from parts of the visible spectrum to which the photographic material in use is nearly or completely insensitive.- Design :...

     (for use in a darkroom
    Darkroom
    A darkroom is a room that can be made completely dark to allow the processing of light sensitive photographic materials, including photographic film and photographic paper. Darkrooms have been created and used since the inception of photography in the early 19th century...

    )
  • Safety lamp
    Safety lamp
    A safety lamp is any of several types of lamp, which are designed to be safe to use in coal mines. These lamps are designed to operate in air that may contain coal dust, methane, or firedamp, all of which are potentially flammable or explosive...

     (for use in coal mines)
  • Searchlight
    Searchlight
    A searchlight is an apparatus that combines a bright light source with some form of curved reflector or other optics to project a powerful beam of light of approximately parallel rays in a particular direction, usually constructed so that it can be swiveled about.-Military use:The Royal Navy used...

     (for military and advertising use)
  • Security lighting
    Security lighting
    In the field of physical security, security lighting is often used as a preventative and corrective measure against intrusions or other criminal activity on a physical piece of property. Security lighting may be provided to aid in the detection of intruders, to deter intruders, or in some cases...

  • Step light
  • Strobe 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...

  • Theatrical
    • Stage lighting instrument
      Stage lighting instrument
      Stage lighting instruments 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 studios and sound stages.Many stagecraft terms vary between the United States and the United...

    • Intelligent lighting
      Intelligent lighting
      Intelligent lighting refers to stage lighting that has automated or mechanical abilities beyond those of traditional, stationary illumination. Although the most advanced intelligent lights can produce extraordinarily complex effects, the intelligence lies with the programmer of the show rather...

    • Followspot
      Followspot
      A followspot, sometimes known as a spot light, is a powerful stage lighting instrument which projects a bright beam of light onto a performance space. Followspots are controlled by a spotlight operator who follows actors around the stage...

  • Wallwasher
    Wallwasher
    Wallwashing is a popular name for a lighting design technique for illumination of large surfaces. It is mainly used with contemporary architecture; in public cultural buildings, museums and galleries; and in landscape lighting....



Lamp types

  • Fuel lamps
Betty lamp
Betty lamp
The Betty lamp is thought to be of German, Austrian, or Hungarian origin. The Betty Lamp first came into use in the 18th century. They were commonly made of iron or brass and were most often used in the home or workshop. These lamps burned fish oil or fat trimmings and had wicks of twisted...

, butter lamp
Butter lamp
Butter lamps are a conspicuous feature of Tibetan Buddhist temples and monasteries throughout the Himalayas. The lamps traditionally burn clarified yak butter, but now often use vegetable oil or vanaspati ghee....

, carbide lamp
Carbide lamp
Carbide lamps, properly known as acetylene gas lamps, are simple lamps that produce and burn acetylene which is created by the reaction of calcium carbide with water....

, gas lighting
Gas lighting
Gas lighting is production of artificial light from combustion of a gaseous fuel, including hydrogen, methane, carbon monoxide, propane, butane, acetylene, ethylene, or natural gas. Before electricity became sufficiently widespread and economical to allow for general public use, gas was the most...

, kerosene lamp
Kerosene lamp
The kerosene lamp is a type of lighting device that uses kerosene as a fuel. This article refers to kerosene lamps that have a wick and a tall glass chimney. Kerosene lanterns that have a wick and a glass globe are related to kerosene lamps and are included here as well...

, oil lamp
Oil lamp
An oil lamp is an object 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 is continued to this day....

, rush light, torch
Torch
A torch is a fire source, usually a rod-shaped piece of wood with a rag soaked in pitch and/or some other flammable material wrapped around one end. Torches were often supported in sconces by brackets high up on walls, to throw light over corridors in stone structures such as castles or crypts...

, candle
Candle
A candle is a solid block or cylinder of wax with an embedded wick, which is lit to provide light, and sometimes heat.Today, most candles are made from paraffin. Candles can also be made from beeswax, soy, other plant waxes, and tallow...

, Limelight
Limelight
Limelight is a type of stage lighting once used in theatres and music halls. An intense illumination is created when an oxyhydrogen flame is directed at a cylinder of quicklime , which can be heated to 2572 °C before melting. The light is produced by a combination of incandescence and...

, gas mantle
Gas mantle
An incandescent gas mantle, gas mantle, or Welsbach mantle is a device for generating bright white light when heated by a flame. The name refers to its original heat source, existing gas lights, which filled the streets of Europe and North America in the late 19th century, mantle referring to the...

Safety lamp
Safety lamp
A safety lamp is any of several types of lamp, which are designed to be safe to use in coal mines. These lamps are designed to operate in air that may contain coal dust, methane, or firedamp, all of which are potentially flammable or explosive...

s: Davy lamp
Davy lamp
The Davy lamp is a safety lamp with a wick and oil vessel burning originally a heavy vegetable oil, devised in 1815 by Sir Humphry Davy. It was created for use in coal mines, allowing deep seams to be mined despite the presence of methane and other flammable gases, called firedamp or minedamp.Sir...

 & Geordie lamp
Geordie lamp
The Geordie lamp was invented by George Stephenson in 1815 as a solution to explosions due to firedamp in coal mines.Although controversy arose between Stephenson's design and the Davy lamp, , Stephenson's original design worked on significantly different principles...

  • Arc lamp
    Arc lamp
    "Arc lamp" or "arc light" is the general term for a class of lamps that produce light by an electric arc . The lamp consists of two electrodes, first made from carbon but typically made today of tungsten, which are separated by a gas...

    s
Xenon arc lamp
Xenon arc lamp
A xenon arc lamp is a specialized type of gas discharge lamp, an electric light that produces light by passing electricity through ionized xenon gas at high pressure to produce a bright white light that closely mimics natural sunlight...

, Yablochkov candle
Yablochkov candle
A Yablochkov candle is a type of electric carbon arc lamp, invented in 1876 by Pavel Yablochkov.-Design:A Yablochkov candle consists of a sandwich of two long carbon blocks, approximately 6 by 12 millimetres in cross-section, separated by a block of inert material such as plaster of paris or kaolin...

  • Incandescent lamp
    Incandescent light bulb
    The incandescent light bulb, incandescent lamp or incandescent light globe makes light by heating a metal filament wire to a high temperature until it glows. The hot filament is protected from air by a glass bulb that is filled with inert gas or evacuated. In a halogen lamp, a chemical process...

A-lamp, Parabolic aluminized reflector lamp (PAR
Parabolic aluminized reflector light
A parabolic aluminized reflector lamp is a type of electric lamp that is widely used in commercial, residential, and transportation illumination. Usage includes locomotive headlamps, aircraft landing lights, and residential and commercial recessed lights...

), reflector lamp (R), bulged reflector lamp (BR) (refer to lamp shapes)
  • Obsolete types: limelight
    Limelight
    Limelight is a type of stage lighting once used in theatres and music halls. An intense illumination is created when an oxyhydrogen flame is directed at a cylinder of quicklime , which can be heated to 2572 °C before melting. The light is produced by a combination of incandescence and...

    , carbon button lamp
    Carbon button lamp
    The carbon button lamp is a single-electrode incandescent lamp invented by Nikola Tesla as one of a few improved lighting sources with regards to Thomas Edison's Incandescent light bulb. A carbon button lamp contains a small carbon sphere positioned in the center of an evacuated glass bulb...

    , Mazda (light bulb)
    Mazda (light bulb)
    Mazda was a trademarked name created by the Shelby Electric Company for incandescent light bulbs. The name was used from 1909 through 1945 in the United States by Shelby and later General Electric; Mazda brand light bulbs were made for decades after 1945 outside the USA...

    , Nernst glower
    Nernst glower
    The Nernst glower is an obsolete device for providing a continuous source of infrared radiation for use in spectroscopy. Typically it was in the form of a cylindrical rod or tube composed of a mixture of certain oxides such as zirconium oxide , yttrium oxide and erbium oxide at a ratio of...

  • Novelty: Lava lamp
    Lava lamp
    A lava lamp is a decorative novelty item that contains blobs of colored wax inside a glass vessel filled with clear liquid; the wax rises and falls as its density changes due to heating from a incandescent light bulb underneath the vessel. The appearance of the wax is suggestive of pāhoehoe lava,...

  • Special purpose: heat lamp, Globar
    Globar
    A Globar is a silicon carbide rod of 5 to 10 mm width and 20 to 50 mm length which is electrically heated up to . When combined with a downstream variable interference filter, it emits radiation from 4 to 15 micrometres wavelength...

    , gas mantle
    Gas mantle
    An incandescent gas mantle, gas mantle, or Welsbach mantle is a device for generating bright white light when heated by a flame. The name refers to its original heat source, existing gas lights, which filled the streets of Europe and North America in the late 19th century, mantle referring to the...

  • Halogen – special class of incandescent lamps
  • Gas-discharge lamp
    Gas-discharge lamp
    Gas-discharge lamps are a family of artificial light sources that generate light by sending an electrical discharge through an ionized gas, i.e. a plasma. The character of the gas discharge critically depends on the frequency or modulation of the current: see the entry on a frequency classification...

    and high-intensity discharge lamp
    High-intensity discharge lamp
    High-intensity discharge lamps are a type of electrical 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 tube. This tube is filled with both gas and metal salts. The gas facilitates the...

     (HID)
Mercury-vapor lamp
Mercury-vapor lamp
A mercury-vapor lamp is a gas discharge lamp that uses an electric arc through vaporized mercury to produce light. The arc discharge is generally confined to a small fused quartz arc tube mounted within a larger borosilicate glass bulb...

, Metal-halide (HMI
Hydrargyrum medium-arc iodide
Hydrargyrum medium-arc iodide, or HMI, is a Osram brand metal-halide gas discharge medium arc-length lamp manufactured for the film and entertainment industry. Hydrargyrum is Latin for mercury...

, HQI, CDM
Ceramic discharge metal halide lamp
The ceramic discharge metal-halide lamp, mostly referred to as Ceramic Metal Halide lamp , is a relatively new source of light that is a variation of the old mercury-vapour lamp. The discharge is contained in a ceramic tube. During operation, the temperature of this ceramic tube can exceed 1200...

), Sodium vapor or "high-pressure sodium"
  • Neon sign
    Neon sign
    Neon signs are made using electrified, luminous tube lights 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 December, 1910 by Georges Claude at the Paris Motor Show. While they are used worldwide, neon signs...

    ,
  • Plasma lamp
    Plasma lamp
    Plasma globes, or plasma lamps , are novelty items that were most popular in the 1980s...

  • Fluorescent
Fluorescent lamp
Fluorescent lamp
A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor. The excited mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce, producing visible light. A fluorescent lamp converts electrical power into useful...

, compact fluorescent lamp
Compact fluorescent lamp
A compact fluorescent lamp , also called compact fluorescent light, energy-saving light, and compact fluorescent tube, is a fluorescent lamp designed to replace an incandescent lamp; some types fit into light fixtures formerly used for incandescent lamps...

 (CFL), Induction lamp, blacklight.
  • Cold cathode
    Cold cathode
    A cold cathode is a cathode used within nixie tubes, gas discharge lamps, discharge tubes, and some types of vacuum tube which is not electrically heated by the circuit to which it is connected...

  • Fiber optics
  • Light-emitting diode
    Light-emitting diode
    A light-emitting diode is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting...

     (LED) (solid-state lighting
    Solid-state lighting
    Solid-state lighting refers to a type of lighting that uses semiconductor light-emitting diodes , organic light-emitting diodes , or polymer light-emitting diodes as sources of illumination rather than electrical filaments, plasma , or gas.The term "solid state" refers commonly to light emitted...

    )
  • Nuclear: self-powered lighting
    Self-powered lighting
    Tritium illumination 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, fluorescent light is created, a process called radioluminescence...


Light-fixture controls

  • Light switch
    Light switch
    A light switch is a switch, most commonly used to operate electric lights, permanently connected equipment, or electrical outlets. In torches the switch is often near the bulb, but may be in the tail, or even the entire head itself may constitute the switch .-Wall-mounted switches:Switches for...

     (often part of the light socket or power cord
    Power cord
    A power cord, line cord, or mains cable is a cable that temporarily connects an appliance to the mains electricity supply via a wall socket or extension cord. The terms are generally used for cables using a power plug to connect to a single-phase alternating current power source at the local line...

     on portable fixtures)
  • Dimmer
    Dimmer
    Dimmers are devices used to vary the brightness of a light. By decreasing or increasing the RMS voltage and, hence, the mean power to the lamp, it is possible to vary the intensity of the light output...

  • 3-way 2-circuit switch
  • Motion detector
    Motion detector
    A motion detector is a device for motion detection. That is, it is a device that contains a physical mechanism or electronic sensor that quantifies motion that can be either integrated with or connected to other devices that alert the user of the presence of a moving object within the field of view...

  • Timer
    Timer
    A timer is a specialized type of clock. A timer can be used to control the sequence of an event or process. Whereas a stopwatch counts upwards from zero for measuring elapsed time, a timer counts down from a specified time interval, like an hourglass.Timers can be mechanical, electromechanical,...

  • Touch
    Touch-sensitive lamp
    A touch-sensitive lamp is one that is activated by human touch rather than a flip, pushbutton, or other mechanical switch. These lamps are popular as desk and nightstand lamps. They act on the principle of body capacitance.-External links:*...

  • X10 (industry standard)
    X10 (industry standard)
    X10 is an international and open industry standard for communication among electronic devices used for home automation, also known as domotics. It primarily uses power line wiring for signaling and control, where the signals involve brief radio frequency bursts representing digital information...

     systems

See also

  • Architectural lighting design
    Architectural lighting design
    Architectural lighting design is a field within architecture and architectural engineering that concerns itself primarily with the illumination of buildings. The objective of architectural lighting design is to obtain sufficient light for the purposes of the building, balancing factors of initial...

  • Coefficient of utilization
    Coefficient of utilization
    A coefficient of utilization is a measure of the efficiency of a luminaire in transferring luminous energy to the working plane in a particular area. The CU is the ratio of luminous flux from a luminaire incident upon a work plane to that emitted by the lamps within the luminaire...

  • History of street lighting in the United States
    History of street lighting in the United States
    The use of street lighting was first recorded in the city of Antioch from the 4th century, later in the Arab Empire from the 9th–10th centuries, especially in Cordova, and then in London from 1417 when Henry Barton, the mayor, ordered "lanterns with lights to be hanged out on the winter evenings...

  • Lighting designer
    Lighting designer
    The role of the lighting designer within theatre is to work with the director, choreographer, set designer, costume designer, and sound designer to create an overall 'look' for the show in response to the text, while keeping in mind issues of visibility, safety and cost...

     for the theater
  • List of light sources
  • Luminous efficacy
    Luminous efficacy
    Luminous efficacy is a measure of how well a light source produces visible light. It is the ratio of luminous flux to power. Depending on context, the power can be either the radiant flux of the source's output, or it can be the total electric power consumed by the source.Which sense of the term is...

  • Timeline of lighting technology
    Timeline of lighting technology
    Timeline of lighting technology- Antiquity :* 70,000 BCE A hollow rock, shell, or other natural found object was filled with moss or a similar material that was soaked in animal fat and then ignited.* c. 4500 BCE oil lamps...


External links

  • Look at the Chart and Pick Out the Reflector You Need, Popular Science
    Popular Science
    Popular Science is an American monthly magazine founded in 1872 carrying articles for the general reader on science and technology subjects. Popular Science has won over 58 awards, including the ASME awards for its journalistic excellence in both 2003 and 2004...

    monthly, February 1919, page 75, Scanned by Google Books: http://books.google.com/books?id=7igDAAAAMBAJ&pg=PA75
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK