Gas-discharge lamp
Gas-discharge lamps are a family of artificial light sources that generate light by sending an electric discharge through an ionized gas, a plasma.
Typically, such lamps use a noble gas (argon, neon, krypton, and xenon) or a mixture of these gases. Some include additional substances, such as mercury, sodium, and metal halides, which are vaporized during start-up to become part of the gas mixture.
Single-ended self-starting lamps are insulated with a mica disc and contained in a borosilicate glass gas discharge tube (arc tube) and a metal cap.[1][2] They include the sodium-vapor lamp that is the gas-discharge lamp in street lighting.[3][4][1][2]
In operation, some of the electrons are forced to leave the
The ions typically cover only a very short distance before colliding with neutral gas atoms, which give the ions their electrons. The atoms which lost an electron during the collisions ionize and speed toward the cathode while the ions which gained an electron during the collisions return to a lower energy state, releasing energy in the form of photons. Light of a characteristic frequency is thus emitted. In this way, electrons are relayed through the gas from the cathode to the anode.
The color of the light produced depends on the
Compared to
Some gas-discharge lamps also have a perceivable start-up time to achieve their full light output. Still, owing to their greater efficiency, gas-discharge lamps were preferred over
History
The history of gas-discharge lamps began in 1675 when the French astronomer Jean Picard observed that the empty space in his mercury barometer glowed as the mercury jiggled while he was carrying the barometer.[7] Investigators, including Francis Hauksbee, tried to determine the cause of the phenomenon. Hauksbee first demonstrated a gas-discharge lamp in 1705.[8] He showed that an evacuated or partially evacuated glass globe, in which he placed a small amount of mercury, while charged by static electricity could produce a light bright enough to read by. The phenomenon of electric arc was first described by Vasily V. Petrov in 1802.[9][10][11] In 1809, Sir Humphry Davy demonstrated the electric arc at the Royal Institution of Great Britain.[12][13] Since then, discharge light sources have been researched because they create light from electricity considerably more efficiently than incandescent light bulbs.
The father of the low-pressure gas discharge tube was German glassblower
The introduction of the metal vapor lamp, including various metals within the discharge tube, was a later advance. The heat of the gas discharge vaporizes some of the metal and the discharge is then produced almost exclusively by the metal vapor. The usual metals are sodium and mercury owing to their visible spectrum emission.
One hundred years of research later led to lamps without electrodes which are instead energized by microwave or radio-frequency sources. In addition, light sources of much lower output have been created, extending the applications of discharge lighting to home or indoor use.
The "Ruhmkorff" lamp
Ruhmkorff lamps were an early form of portable electric lamp, named after Heinrich Daniel Ruhmkorff and first used in the 1860s. The lamp consisted of a Geissler tube that was excited by a battery-powered Ruhmkorff induction coil; an early transformer capable of converting DC currents of low voltage into rapid high-voltage pulses. Initially the lamp generated white light by using a Geissler tube filled with carbon dioxide. However, the carbon dioxide tended to break down. Hence in later lamps, the Geissler tube was filled with nitrogen (which generated red light), and the clear glass was replaced with uranium glass (which fluoresced with a green light).[14]
Intended for use in the potentially explosive environment of mining, as well as oxygen-free environments like diving or for a heatless lamp for possible use in surgery, the lamp was actually developed both by Alphonse Dumas, an engineer at the iron mines of Saint-Priest and of Lac, near Privas, in the department of Ardèche, France, and by Dr Camille Benoît, a medical doctor in Privas.[15] In 1864, the French Academy of Sciences awarded Dumas and Benoît a prize of 1,000 francs for their invention.[16] The lamps, cutting-edge technology in their time, gained fame after being described in several of Jules Verne's science-fiction novels.[17]
Color
Each gas, depending on its atomic structure emits radiation of certain wavelengths, its emission spectrum, which determines the color of the light from the lamp. As a way of evaluating the ability of a light source to reproduce the colors of various objects being lit by the source, the International Commission on Illumination (CIE) introduced the color rendering index (CRI). Some gas-discharge lamps have a relatively low CRI, which means colors they illuminate appear substantially different from how they do under sunlight or other high-CRI illumination.
Gas | Color | Spectrum | Notes | Image |
---|---|---|---|---|
Helium | green-blue .
|
Used by artists for special-purpose lighting. | ||
Neon | Red-orange
|
Intense light. Used frequently in neon signs and neon lamps. | ||
Argon | Violet to pale lavender blue | Often used together with mercury vapor .
|
||
Krypton | off-white to green. At high peak currents, bright blue-white .
|
Used by artists for special-purpose lighting. | ||
Xenon | Gray or blue-gray dim white. At high peak currents, very bright green-blue. | Used in xenon arc lamps .
|
||
Nitrogen | Similar to argon but duller, more pink; at high peak currents bright blue-white. | used in the Moore lamp (historically)
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Oxygen | Violet to lavender, dimmer than argon | |||
Hydrogen | Lavender at low currents, pink to magenta over 10 mA | |||
Water vapor | Similar to hydrogen, dimmer | |||
Carbon dioxide | Blue-white to pink, at lower currents brighter than xenon | Used in Moore lamp (historically).
|
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Mercury vapor | Light blue, intense ultraviolet | Ultraviolet not shown on this spectral image.
Used in combination with mercury-vapor lamps and fluorescent tubes .
|
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Sodium vapor (low pressure) | Bright orange-yellow | Widely used in sodium-vapor lamps. |
Types
Lamps are divided into families based on the pressure of gas, and whether or not the cathode is heated.
Low pressure discharge lamps
Low-pressure lamps have working pressure much less than atmospheric pressure. For example, common fluorescent lamps operate at a pressure of about 0.3% of atmospheric pressure.
Fluorescent lamps, a heated-cathode lamp, the most common lamp in office lighting and many other applications, produces up to 100 lumens per watt
Neon lighting, a widely used form of cold-cathode specialty lighting consisting of long tubes filled with various gases at low pressure excited by high voltages, used as advertising in neon signs.
Low pressure
A small discharge lamp containing a
Continuous glow lamps are produced for special applications where the electrodes may be cut in the shape of alphanumeric characters and figural shapes.[18]
A flicker light bulb, flicker flame light bulb or flicker glow lamp is a gas-discharge lamp which produces light by
High pressure discharge lamps
High-pressure lamps have a discharge that takes place in gas under slightly less to greater than atmospheric pressure. For example, a high pressure sodium lamp has an arc tube under 100 to 200 torr pressure, about 14% to 28% of atmospheric pressure; some automotive HID headlamps have up to 50 bar or fifty times atmospheric pressure.
High pressure mercury-vapor lamps are the oldest high pressure lamp type and have been replaced in most applications by metal halide and the high pressure sodium lamps. They require a shorter arc length.
High-intensity discharge lamps
A high-intensity discharge (HID) lamp is a type of
HID lamps are typically used when high levels of light and energy efficiency are desired.
Other examples
The
Alternatives
- Incandescent lamps: They have low manufacturing costs;[20]
- White LED lamp. The efficiency of white LED lamps is 61-200 lm/W.[21]
- Battery-powered lanterns (filling with krypton or xenon).
See also
- Electric arc
- Electric glow discharge
- Emission spectrum
- Fluorescent lamp
- Gas-filled tube
- Hydrargyrum medium-arc iodidelamp
- List of light sources
- Over-illumination
References
- ^ a b "The Low Pressure Sodium Lamp".
- ^ a b "The Low Pressure Sodium Lamp".
- ^ "Lighting Comparison: LED vs High Pressure Sodium/Low Pressure Sodium". www.stouchlighting.com.
- ^ "The Sodium Lamp - How it works and history". edisontechcenter.org.
- ^ "Types of Lighting". Energy.gov. US Department of Energy. Retrieved 10 June 2013.
- ^ "Lighting technologies: a guide to energy-efficient illumination" (PDF). Energy Star. US Environmental Protection Agency. Retrieved 10 June 2013.
- ^ See:
- (Staff) (1676). "Experience faire à l'Observatoire sur la Barometre simple touchant un nouveau Phenomene qu'on y a découvert" [Experiment done at the [Paris] observatory on a simple barometer concerning a new phenomenon that was discovered there]. Journal des Sçavans (Paris edition) (in French): 112–113. From pp. 112–113: "On sçait que le Barometre simple n'est autre chose qu'un tuyau de verre … toutes les circonstances qu'on y découvrira." (One knows that the simple barometer is nothing more than a glass tube [that is] hermetically sealed at the top and open at the bottom, in which there is mercury which usually stands at a certain height, the remainder [of the tube] above being void. Mr Picard has one of them at the observatory [in Paris] which in the dark — when one shakes it enough to make the mercury jiggle — makes sparks and throws a certain flickering light which fills all of the part of the tube that's void: but it happens during each swing only in the void and only during the descent of the mercury. One has tried to perform the same experiment on various other barometers of the same composition; but so far one has succeeded with only [this] one. As one has resolved to examine the thing in every way, we will give at greater length all the circumstances of this as one discovers them.)
- Reprinted in: (Staff) (1676). "Experience faire à l'Observatoire sur la Barometre simple touchant un nouveau Phénomène qu'on y a découvert" [Experiment done at the [Paris] observatory on a simple barometer concerning a new phenomenon that was discovered there]. Journal des Sçavans (Amsterdam edition) (in French): 132.
- (Staff) (1694). "Sur la lumière du baromètre" [On the light of the barometer]. Histoire de l'Académie Royale des Sciences (in French). 2: 202–203. From p. 202: "Vers l'année 1676, M. Picard faisant transporter son Baromètre, … il ne s'en trouva aucun qui fit de la lumière." (Towards the year 1676, [while] Mr Picard [was] transporting his barometer from the observatory [in Paris] to the port of Saint Michel during the night, he perceived a light in the part of the tube where the mercury was moving; this phenomenon surprising him, he immediately announced it to the [Journal des] Sçavans, and those who had barometers having examined them, they found nothing which made light.) By the time of Picard's death (1682), his barometer had lost its ability to produce light. However, after Philippe de La Hire (1640–1718) restored Picard's barometer, it once again produced light. Cassini (1625–1712) also owned a barometer that produced light.
- See also: Barometric light
- S2CID 186212654.
- ^ Petrov, Vasily (1803). Извѣстіе о Гальвани-Вольтовскихъ Опытахъ [News of Galvanic-Voltaic Experiments] (in Russian). Saint Petersburg, Russia: Printing House of the State Medical College. From pp. 163–164: "Естьли на стеклянную плитку или на скамеечку со стеклянными ножками будуть положены два или три куска древесного угля, … и отъ которого темный покой довольно ясно освѣщенъ быть можетъ." (If on a glass plate or on a bench with glass legs there be placed two or three pieces of charcoal, capable of producing light-bearing phenomena by means of the Galvanic-Voltaic fluid, and if there are then insulated metal conductors (electrodes), in communication with both poles of a huge battery, bring these closer to each other to a distance [i.e., separation] of one to three lines [2.5-7.5 mm]; then there is between them a very bright white light or flame, from which these coals burn quickly or slowly, and by which the darkness may be quite clearly illuminated.)
- S2CID 11047670.
- ^ Petrov also observed electric discharges through low-pressure air. From (Petrov, 1803), p. 176: "Впрочемъ, свѣтъ, сопровождавшій теченіе Гальвани-Вольтовской жидкости въ безвоздушномъ мѣстѣ, былъ яркій, белаго цвѣта, и при томъ не рѣдко оть разкаленнаго конца иголки, либо и ото дна стакана отскакивали искры или какъ бы маленькія звѣздочки." (However, the light accompanying the flow of the Galvanic-Voltaic fluid in the airless space was bright, white in color; and at the same time, not rarely from the incandescent ends of the needles [i.e., electrodes] or from the bottom of the glass, came sparks like small stars.) From (Petrov, 1803), p. 190: "3) Електрическій свѣтъ въ весьма изтонченномъ воздухѣ предстовляетъ несравненно величественнѣйшія явленія, нежели какія могъ я примѣтить отъ свѣта Гальвани-Вольтовской жидкости." (Electric light in very rarefied air presents an incomparably more majestic phenomenon than any that I could perceive from the light of the Galvanic-Voltaic fluid.)
- ^ In 1801 and 1802, Davy observed bright electrical sparks, but not a continuous arc. His battery lacked sufficient voltage and current to sustain an electric arc.
- Davy, H. (1802). "Account of some experiments in Galvanic electricity, made in the theatre of the Royal Institution". Journals of the Royal Institution of Great Britain. 1: 165–167.
- Davy, H. (1802). "Account of some experiments made in the laboratory of the Royal Institution, relating to the agencies of Galvanic electricity, in producing heat, and in effecting changes in different fluid substances". Journals of the Royal Institution of Great Britain. 1: 209–214.
- (Ayrton, 1902), pp. 20-21.
- Davy, Humphry (1810). "The Bakerian Lecture. An account of some new analytical researches on the nature of certain bodies, particularly the alkalies, phosphorus, sulphur, carbonaceous matter, and the acids hitherto undecompounded; with some general observations on chemical theory". Philosophical Transactions of the Royal Society of London. 100: 39–104. From p. 47: " … the electricity passed through the vapour of the potassium, producing a most brilliant flame, of from half an inch to an inch and a quarter in length; … "
- (Ayrton, 1902), pp. 24–27.
- ^ For the early history of electric arcs, see: Ayrton, Hertha (1902). The Electric Arc. New York City, New York, USA: D. Van Nostrand Co. pp. 19 ff.
- ^ Paolo Brenni (2007) "Uranium glass and its scientific uses," Archived 2014-06-30 at the Wayback Machine Bulletin of the Scientific Instrument Society, no. 92, pages 34–39; see page 37.
- ^ See:
- A. Dumas and Benoit (1862) "Physique Appliquée — Note sur un appareil propre à éclairer les ouvriers mineurs dans leurs travaux souterrains au moyen de la lumière d'induction" (Applied physics — Note on an apparatus suitable for providing light for miners in their underground work by means of the induction lamp), Comptes Rendus, vol. 55, pages 439–440.
- Dumas, "Note descriptive de la lampe photo-électrique", Bulletin de la Société de l'Industrie Minérale, vol. 9, pages 5–14 (1863–1864).
- "Lampe Dumas," Bulletin de la Société de l'Industrie Minérale, vol. 9, pages 113–117 (1863–1864).
- "Note sur la lampe électrique de Dumas et Benoît", Bulletin de la Société de l'Industrie Minérale, vol. 9, pages 118–120 (1863–1864).
- Bulletin des Lois de l'Empire Français, series 9, vol. 23, page 639 (1864); see patent application no. 1160°.
- "New safety light for coal mines", Journal of the Franklin Institute, 3rd series, vol. 49, pages 262–263 (1865). Reprinted from the Athenæum (literary magazine of London, England), February 25, 1865.
- Théodose du Moncel, "Application à l'éclairage des galeries de mines," Notice sur l'appareil d'induction électrique de Ruhmkorff (Paris, France: Gauthier-Villars, 1867), pages 394–398.
- See also: Andreas Fehrmann's Jules Verne collection: "Jules Verne und die Elektrizität: Kapitel 2: Die Ruhmkorfflampe" [in German]. Available on-line at: Jules Verne.
- ^ "Prix dit des arts insalubres", Comptes rendus, 60 : 273 (1865).
- ^ Journey to the Center of the Earth (1864), From the Earth to the Moon (1865), and 20,000 Leagues Under the Sea (1869).
- ^ "kilokat's ANTIQUE LIGHT BULB site : neon lamps". bulbcollector.com.
- ^ US patent 3238408, Kayatt Philip J., "Flicker glow lamps", issued 1966-03-1
- ^ "FAQ: phasing out conventional incandescent bulbs". europa.eu. Retrieved July 22, 2022.
- ^ "LED Light Bulb". yourelectricianbrisbane.com.au. 15 March 2022. Retrieved July 22, 2022.
Further reading
- Waymouth, John (1971). Electric Discharge Lamps. Cambridge, MA: The M.I.T. Press. ISBN 978-0-262-23048-3.
- National Highway Traffic Safety Administration. "Glare from headlamps and other front mounted lamps". Federal Motor Vehicle Safety Standard No. 108. US Department of Transportation. Retrieved 2006-01-23.
External links
- Lamps and Indicators at Curlie