Light fixture

A light fixture (US English), light fitting (UK English), or luminaire is an electrical device that contains an electric lamp that provides illumination. 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 fixtures, hard-wired in place.

This article is about architectural light fixtures. For stage lighting, see Stage lighting instrument.
Various examples of light fixtures throughout history

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 chandeliers, 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 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 (with or without a lens), an outer shell or housing for lamp alignment and protection, an electrical ballast or power supply, 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 industry, aerospace, marine and medicine sectors.

Portable light fixtures are often called lamps, as in table lamp or desk lamp. In technical terminology, the lamp is the light source, which, in casual terminology, is called the light bulb. The International Electrotechnical Commission (IEC) recommends the term luminaire for technical use.

History

Fixture manufacturing began soon after production of the incandescent light bulb. 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.[1]

  • Neoclassical light fixture; mid-19th century; bronze; height: 18 cm; Hallwyl Museum (Stockholm, Sweden)
  • Lamp and lampshade made of Tiffany glass; circa 1890-1900; Budapest Museum of Applied Arts (Budapest, Hungary)
  • Lamp; 1902-1918; lead and glass; 67.9 x 52.1 cm; Metropolitan Museum of Art (New York City)
  • "Daffodil" lamp; 1904–1924; leaded opalescent glass and gilt bronze; height: 67.9 cm, diameter of shape: 51.4 cm; Metropolitan Museum of Art

Fixture types

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

Free-standing or portable

Fixed
  • Ceiling Dome – Also called 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 – 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 – 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.
Chandeliers in the Bibliothèque Mazarine (Paris)
  • Surface-mounted light – the finished housing is exposed, not flush with surface
    • Chandelier
    • 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 – May sometimes have a light, often referred to as a light kit mounted to it.
    • 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 stores
    • Strip lights or Industrial lighting – often long lines of fluorescent lamps used in a warehouse or factory
A decorative outdoor lamp at Leeds Town Hall.
A garden solar lamp is an example of landscape lighting
  • Outdoor lighting and landscape lighting – used to illuminate walkways, parking lots, roadways, building exteriors and architectural details, gardens, and parks. 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-mounted – for landscape, roadways, and parking lots
    • Bollard – 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
    • Yard light

Special-purpose lights

Lamp types
Old table lamps at Archaeological Museum, Sri Lanka
Main article: List of light sources
Xenon arc lamp, Yablochkov candle
Fluorescent lamp, compact fluorescent lamp (CFL), Induction lamp, blacklight.
  • Fuel lamps
Betty lamp, butter lamp, carbide lamp, gas lighting, kerosene lamp, oil lamp, rush light, torch, candle, Limelight, gas mantle
Safety lamps: Davy lamp and Geordie lamp
Mercury-vapor lamp, Metal-halide (HMI, HQI, CDM), Sodium vapor or "high-pressure sodium"
A-lamp, Parabolic aluminized reflector lamp (PAR), reflector lamp (R), bulged reflector lamp (BR) (refer to lamp shapes)

Light-fixture controls
Neoclassical light fixture; mid-19th century; bronze; height: 18 cm; Hallwyl Museum (Stockholm, Sweden)
gollark: Technically, superglobal, I guess.
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See also

References
  1. "Early industry leaders", of fluorescent fixture manufacturing, Paul Levy (1998)
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