Glass tubing can be turned into new glass articles, brass and aluminum in end caps can be reused, the internal coating can be reprocessed for use in paint pigments, and the mercury contained in the lamp can be reclaimed and used in new lamps. We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites. For green, a terbium-activated Gd2O2Tb3+; its color purity and brightness at low excitation densities is worse than the zinc sulfide alternative, but it behaves linear at high excitation energy densities, while zinc sulfide saturates. Registered by United States Radium Corporation. A T8 lamp has proportionally less phosphor due to its smaller size. Effects related to electron irradiation degradation are therefore more pronounced. The black-and-white television screens require an emission color close to white. Their color palette is, however, very limited. It’s a coating of one or more phosphor compounds which flouresce at a light frequency visible to the human eye when energised by the UV frequency photons emitted from an electrical arc through the ionised gas in the tube. Full disclaimer here. A fluorescent lamp utilizing a dual layer phosphor coating is disclosed wherein the base layer utilizes a first phosphor mixture and the top phosphor layer in said coating comprises a blend of narrow bandwith emitting phosphors to improve the color rendering capability of these lamps. A fluorescent lamp is a low weight mercury vapour lamp that uses fluorescence to deliver visible light. While the positive hole gets close vicinity of the activator it captures the electron from the activator. Florescent bulbs produce Ultra Violet (UV) light when an electrical arc is run through inert, or semi-inter, gasses that contain mercury ions. A single, white-emitting phosphor, (Zn,Cd)S:Ag,Au,Al overcomes this obstacle. Fluorescent bulbs contain an electric current in a low-pressure mercury vapor, which produces UV light. The arc in the lamp causes electrons to strike mercury atoms, raising their electrons to a higher energy state. It is used to convert ultraviolet ray radiation into visible radiation. Mercury-containing lamps can be recycled to recover the mercury, as well as the glass, plastic and phosphor powder, they contain. Phosphor Some fluorescent lamps (CovRguard products) use an external coating of polycarbonate to provide a shatter-resistant coating. When a flourescent tube … An electric current in the gas excites mercury vapor which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow. Improved Luminous Flux of Fluorescent Lamps by Making Phosphor Layer Uniform. Fluorescent lamps are lamps in which light is produced as a result of flow of free electrons and ions inside a gas. The phosphor is in fact a blend of two different materials which radiate broadly in the blue and orange parts of the spectrum respectively. The requirements of general lighting phosphors are similar to those of fluorescent lamps—in terms of the wavelength of excitation (440-480 nm) and the temperature and moisture stability requirements. If cut with fluorescent lamp glass, any phosphor that goes in the wound is likely to stop blood clotting and can interfere with curing. Photographic registration on orthochromatic film materials, Display tubes, Electronic Portal Imaging Devices (EPIDs) used in radiation therapy linear accelerators for cancer treatment, 2600 to 9900 K, for very high output lamps, High Pressure Mercury and Metal Halide Lamps, Special fluorescent lamps for medical use, ZnS:Mn, used in AC thin-film electroluminescent (ACTFEL) devices degrades mainly due to formation of, ZnS and CdS phosphors degrade by reduction of the metal ions by captured electrons. A phosphor, most generally, is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy.The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or visible light, and cathodoluminescent substances which glow when struck by an electron beam (cathode rays) in a cathode ray tube. Some other phosphors commercially available, for use as X-ray screens, neutron detectors, alpha particle scintillators, etc., are: Please expand the section to include this information. The phosphor improves the colour rendering properties and luminous efficacy. So I went looking for more information and it seems that all articles I can find on the Internet mentioning the danger of the phosphor coating have wording derived from The Fluorescent Lighting System, which states: The biggest immediate injury threat from a broken lamp is from the phosphor-coated glass. Some fluorescent lamps (CovRguard products) use an external coating of polycarbonate to provide a shatter-resistant coating. T8 Fluorescent Lamps ... are primarily determined by the phosphor coating inside the lamp. A typical fluorescent lamp is composed of a phosphor coated glass tube with electrodes located at either end. Subsequently, a fluorescent coating (called the phosphor) on the inner surface of the tube absorbs the ultraviolet light and converts it into fluorescent light, mostly in the visible spectral region. i did think the original tube from a my grandparents 1938 desk lamp had dead phosphor till it ran a while.just condensed mercury.i got it in 2002. not as bright as modern tubes but it still works. Later contemporary lamps had used the phosphor that was the mixture of calcium halophosphate and magnesium tungstate. Previously zinc beryllium silicate was used as the basic phosphor. This excess electron migrates from one zinc ion to another through the crystal lattice in the conduction band. A fluorescent lamp converts electrical energy into useful light much more efficiently than incandescent lamps. For blue color, ZnS:Ag,Cl is employed. One example of the activator is silver. Such displays can have high resolution, due to absence of two-dimensional structuring of RGB CRT phosphors. A fluorescent lamp utilizing a dual layer phosphor coating is disclosed and with the base layer employing a calcium halophosphate phosphor which has been modified to provide efficient lumen output at a substantially reduced coating weight. The phosphor system (SP/SPX) uses a mixture of rare earth elements such as lanthanum and yttrium as either an oxide or as a phosphate, along with a barium/aluminum oxide. Article. The fluorescent tubes used in the past, are phosphors of Zinc Beryllium Silicate – the first material to create white light with reasonable quality. A 253.7 nm photon impinges on the phosphor and causes the electron jump from divalent sulfur to divalent zinc. A typical Fluorescent lamp consists of a glass tube coated with phosphor and containing a pair of electrodes at each end. Fluorescent Lighting. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.) When the UV strikes the phosphor coating on the inside of … when an excess of silica gel (formed from the potassium silicate binder) is present, have tendency to locally overheat due to poor thermal conductivity. In this respect, let's go back to the link to the above publication and think at the XeF* (354nm), I2* (342nm), and XeCl* (308nm). The blue phosphor stayed generally unchanged, a silver-doped zinc sulfide. This light then causes a phosphor to fluoresce, producing visible light.. B – E :- Electron Migration Further details may exist on the, CS1 maint: BOT: original-url status unknown (, Lagos C (1974) "Strontium aluminate phosphor activated by cerium and manganese", "Silicon-based oxynitride and nitride phosphors for white LEDs—A review", "Fine yellow α-SiAlON:Eu phosphors for white LEDs prepared by the gas-reduction–nitridation method", "PPT presentation in Polish (Link to achieved version; Original site isn't available)", "Luminescence and temperature dependency of β-SiAlON phosphor", "Frequency characteristics of modern LED phosphor materials", https://www.electrochem.org/dl/interface/wtr/wtr09/wtr09_p032-036.pdf, Silicon-based oxynitride and nitride phosphors for white LEDs—A review, Inorganic Phosphors Compositions, Preparation and Optical Properties, William M. Yen and Marvin J. Weber, https://en.wikipedia.org/w/index.php?title=Phosphor&oldid=990573354, CS1 maint: BOT: original-url status unknown, Articles lacking reliable references from January 2013, Articles with disputed statements from September 2019, Articles to be expanded from October 2020, Creative Commons Attribution-ShareAlike License. Later contemporary lamps had used the phosphor that was the mixture of calcium halophosphate and magnesium tungstate. (La,Gd)OBr:Ce,Tb3+ can be used as an alternative that is more linear at high energy densities. Novel red emitting phosphors for use in fluorescent lamps resulting in superior color rendering index values compared to conventional red phosphors. CONFERENCE PROCEEDINGS Papers Presentations Journals. The tube also contains a phosphor powder , coated along the inside of the glass. The quartz glass arc tube transmits ultraviolet light and enables a phosphor coating to be used on the inside of the outer envelope. For producing eye pleasant light phosphor is used inside of the fluorescent lamp. For example, a standard cool white Usually, a combination of phosphors is employed. It creates, at this moment, univalent zinc ion in the conduction band. None of these materials would present a hazard in the event of breakage of the lamp, aside from the obvious ones due to broken glass. Black and white TV CRTs and display tubes, Cd free. Mercury vapor lamps have a lower light output and are the least efficient members of the HID family. i doubt the phosphor degrades.its in a vacuum with argon/neon/krypton gas and a bit of mercury. fluorescent lamp 1. a type of lamp in which an electrical gas discharge is maintained in a tube with a thin layer of phosphor on its inside surface. February 2002; JOURNAL OF THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN 86(2):63-66 The acceleration voltage is used to determine the energy of the electrons; lower-energy ones are absorbed in the top layer of the phosphor, while some of the higher-energy ones shoot through and are absorbed in the lower layer. Secrion I smaller lamps are also other applications because of their high efficiency, low operating temperm, and long lifetime. The brightness of one is linearly dependent on electron flux, while the other one's brightness saturates at higher fluxes—the phosphor does not emit any more light regardless of how many more electrons impact it. Phosphors used for fluorescent lamps require a multi-step production process, with details … lamp contains 4-5 grams of phosphor coating. In most cases, a fluorescent lamp produces white light rather than colored light. For displaying of a limited palette of colors, there are a few options. fill gas consisting essentially of mercury vapor and argon at elevated pressure, elevated phosphor coating weight, and an alpha- and gamma-alumina blended UV-reflective barrier layer) produces substantially the same or greater lumens, and has similarly tunable color rendering and color temperature characteristics, as a … Said phosphor materials can be further combined with other phosphors to produce white color illumination in said type lamps. D – C :- Electron Jump Black and white TV CRTs and display tubes. In addition of activators with phosphor material a permitted energy level is created in the forbidden zone. NA Smith, in Electrical Engineer's Reference Book (Sixteenth Edition), 2003. It has peak spectral sensitivity near 253.7 nm. This in turn excites a white phosphor coating on the inside of the tube, which emits visible light throughout the surface of the tube. The typical luminous efficacyof fluorescent lighting systems is 50–100 lumens per watt, several … Our fluorescent materials are widely used for making fluorescent lamps, mercury lamps, neon lamps, UV lamps, cold cathode lamp, PDP, LED, printing ink, anti-forgery powder, diazo printing powder and also could be adjusted of special using for plant growth lamps, aquatic animal lamps and etc. (Any remaining ultraviolet light is absorbed in the glass tube.) The phosphor coating in a fluorescent lamp is a critical component in the lamp’s operation. They were developed to overcome problems with fluorescent lamps for outdoor use but are less energy efficient than Linear fluorescent lamps are omnidirectional sources; that is, they emit light in all directions. However, the efficiency of tubes using these materials was just 35 lumens per watt. Phosphor. (Supervisory Control and Data Acquisition), Programmable Logic Controllers (PLCs): Basics, Types & Applications, Diode: Definition, Symbol, and Types of Diodes, Thermistor: Definition, Uses & How They Work, Half Wave Rectifier Circuit Diagram & Working Principle, Lenz’s Law of Electromagnetic Induction: Definition & Formula. Electrical4U is dedicated to the teaching and sharing of all things related to electrical and electronics engineering. Other ones are ZnS:Ag+(Zn,Cd)S:Ag (blue+yellow), and ZnS:Ag+ZnS:Cu,Al+Y2O2S:Eu3+ (blue + green + red – does not contain cadmium and has poor efficiency). Loosely packed phosphors, e.g. A fluorescent lamp or fluorescent tube is a gas-discharge lamp that uses electricity to excite mercury vapor in argon or neon gas, resulting in a plasma that produces short-wave ultraviolet light. But now a day’s Phosphor is actually a semiconductor material that has been mixed with activators. In beam penetration tubes, different color phosphors are layered and separated with dielectric material. This is because of sophisticated refinements in the composition of the phosphor coating on the inside of the tube. A water-base phosphor-coating composition adapted for use in depositing an adherent layer of phosphor on the inner surface of a fluorescent lamp envelope which has previously been provided with a transparent film of conductive material, said phosphor-coating composition containing, by weight based on the phosphor content, from about 0.1% to 0.6% finely divided aluminum oxide, from about 0.1% to … However, it saturates. Therefore, most mercury vapor lamps have a phosphor coating that alters the color and improves color rendering to some extent. E – D :- Electron Jump Remote phosphor coating, in which the phosphor layer is some distance above the LED chip, was proposed for reducing the amount of light trapped in LED chips and improving the luminous efficiency of white LEDs. Phosphor Coating Inside Lamp Glass Envelope/Tube UV Light Visible Light EXTERNAL INDUCTOR LAMP HOW DOES INDUCT ION LIGHTING WORK? Warm White High Purity Halo Phosphor Used For Fluorescent Lamp , Find Complete Details about Warm White High Purity Halo Phosphor Used For Fluorescent Lamp,Halo Phosphor,Warm White High Purity Halo Phosphor,Halo Phosphor Used For Fluorescent Lamp from Rare Earth & Products Supplier or Manufacturer-Zhejiang Jingneng Phosphor Material Co., Ltd. At low electron flux, both phosphors emit together; at higher fluxes, the luminous contribution of the nonsaturating phosphor prevails, changing the combined color.[26]. Early fluorescent lamps used a single halophosphor coating and could offer improved color quality only with an accompanying decrease in efficacy (LPW). Expired - Lifetime Application number US08/247,919 Inventor Arunava Dutta Leonard V. Dullea Incandescent bulbs are the traditional option, the first type of light bulb invented and … The evolution of the phosphors was therefore (ordered by B-G-R): For projection televisions, where the beam power density can be two orders of magnitude higher than in conventional CRTs, some different phosphors have to be used. The most common combination is ZnS:Ag+(Zn,Cd)S:Cu,Al (blue+yellow). Some 4-pin Compact fluorescent lamps contain 2-3 mg of titanium-hydride. The phosphors used in standard T12 cool white and warm white lamps are halophosphates, which usually can only provide either good color quality or high efficacy. Fluorescent lamps require a special power supply called a ballast that is needed to regulate lamp operating current ... engineered phosphor coating on the inside of the tube, which emits white, visible light throughout the surface of the tube. By changing the ratio of the two components a … Green phosphors based on ZnS:Cu do not have to be coated due to their own yellowish color.[5]. Overview. As the compositions contain discrete grains of different phosphors, they produce image that may not be entirely smooth. In most cases, a fluorescent lamp produces white light rather than colored light. B. MERCURY: Mercury is present in small amounts in all fluorescent lamps. The excited vapor then emits invisible ultraviolet light that is absorbed by the bulb's phosphor coating. Shorter life and smaller size lamps generally have A low pressure mercury electric discharge lamp, tubular in shape in which a fluorescent coating (phosphor) transforms ultraviolet energy into visible light. Univalent zinc ion means zinc ion with an excess electron. A fluorescent lamp is a low weight mercury vapour lamp that uses fluorescence to deliver visible light. Phosphor Model of Zinc Sulfide, A – B :- Electron Jump in some older military radar displays. Color CRTs require three different phosphors, emitting in red, green and blue, patterned on the screen. A fluorescent lamp or fluorescent tube is a low-pressure mercury-vapor gas-discharge lamp that coated on the inside with a fluorescent material in the form of a powder which is excited by the ultra-violet radiation of different colours, while by mixing the powders … The phosphors in color CRTs need higher contrast and resolution than the black-and-white ones. A – C :- Hole Migration. The color tone can be adjusted by the ratios of the components. phosphor coating glass fluorescent lamp Prior art date 1992-06-09 Legal status (The legal status is an assumption and is not a legal conclusion. A class of non-stoichiometric class of cerium and terbium co-activated magnesium aluminate phosphors is disclosed which are particularly useful in low pressure type fluorescent lamps. Although fluorescent lamps are available in numerous lengths, diameters, and configurations, this Sometimes, the phosphor coating on the inside of fluorescent lights includes phosphorus in the metallic salt lining the inside of the light bulb. The green phosphor initially used manganese-doped zinc silicate, then evolved through silver-activated cadmium-zinc sulfide, to lower-cadmium copper-aluminium activated formula, and then to cadmium-free version of the same. It illuminates the very eye pleasant light. The biggest immediate injury danger from a damaged lamp is from the phosphor-coated glass. EXTERNAL INDUCT OR LAMPS External magnetic induction lamps are essentially fluorescent lamps with electromagnets wrapped around a section of the lamp tube. Electrons flow through the fluorescent lamp and collide with mercury atoms, causing photons of UV light to be released. A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. Our Sunbright Ultra High Output lamps are manufactured in Europe and are a ‘Multi-Phosphor’ lamp, with additional coatings, compared to the usual Asian or Malaysian made Fluorescent lamps generally available in the New Zealand market. An electric current in the gas excites mercury vapor, which produces short-wave ultraviolet light that then causes a phosphor coating on the inside of the lamp to glow. A wide variety of different whites can be created by the halophosphate system. Early fluorescent lamps used a single halophosphor coating and could offer improved color quality only with an accompanying decrease in efficacy (LPW). For producing eye pleasant light phosphor is used inside of the fluorescent lamp. So either the first color or a mixture of the first and second color is shown. 16.1.3.2 Phosphor materials used in LED for general lighting. The central element in a fluorescent lamp is a sealed glass tube. They were used e.g. These coatings produce light by having particles of radiation hit the coating from the inside of the tube, causing them to fluoresce. The ultraviolet ray to visible ray conversion is shown pictorially below. - Take also in consideration the fluorescent coatings used for high pressure mercury lamps, that are appreciated as sensitive to the near UV wavelengths. A fluorescent lamp or a fluorescent tube is a low pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. Three separate electron guns are used for color production (except for displays that use beam-index tube technology, which is rare). The UV light is then converted into visible light as it passes through the phosphor coating on … Radar screens; turns from translucent white to dark magenta, stays changed until erased by heating or infrared light, Flying spot scanning systems and photographic applications, Registered by Allen B DuMont Laboratories. Fluorescent Lamp is still the mostly used light source in our day to day life. Also disclosed is a fluorescent lamp including a phosphor layer comprising blends of one or more of a blue phosphor, a blue-green phosphor… For example in F32T8/RE830: F means Fluorescent Lamp; 32 stands for 32 watts; T8 denotes diameter in eighth of an inch, which is 1 (8/8); RE refers to the use of Rare Earth Phosphor coating, and the first digit 8 in 830 refers to 80 CRI and 30 signifies 3000K colour temperature. It is used to convert ultraviolet ray radiation into visible radiation. The amount of mercury will vary in any given lamp depending on the design life and size of the lamp. Fluorescent lamps offer more color options than any other lamp type. The tube contains mercury, of which only a very small amount is initially in vapor form. Some fluorescent lamps (CovRguard products) use an external coating of polycarbonate to provide a shatter-resistant coating. pin Compact fluorescent lamps contain 2-3 mg of titanium-hydride. Previously zinc beryllium silicate was used as the basic phosphor. Cerium doped YAG Phosphor, Yellow, Used in white, This page was last edited on 25 November 2020, at 07:46. Unlike incandescent lamps, fluorescent lamps always require a ballast to regulate the flow of power through the lamp. Due to its low efficiency, it is used only on very small screens. lamp consisting of a tube coated on the inside with a fluorescent material; mercury vapor in the tube emits ultraviolet radiation that is converted to visible radiation by the fluorescent material This is because of sophisticated refinements in the composition of the phosphor coating on the inside of the tube. The M, Europium(II)-doped alkaline earth aluminates degrade by formation of, Oxide phosphors can degrade rapidly in presence of. Request PDF | Modeling the role of phosphor grain packing in compact fluorescent lamps | Compact fluorescent lamps contain mercury gas which generates ultraviolet radiation. Fluorescent lamps created to replace incandescent light bulbs effectively save energy, but they emit more UV light. The composition of the phosphors changed over time, as better phosphors were developed and as environmental concerns led to lowering the content of cadmium and later abandoning it entirely. Just simultaneously, the positive hole migrates from one sulfur atom to another in the valence band. With a display with red outer layer and green inner layer, the manipulation of accelerating voltage can produce a continuum of colors from red through orange and yellow to green. Phosphor coating inside fluorescent lamps convert ultraviolet rays, produced from the collision between mercury atoms and electrons, to visible light. nAl2O3) or ultramarine (Na8Al6Si6O24S2). This version of phosphor coating produced yellowish white light but later bluish white. The screens are typically covered with phosphor using sedimentation coating, where particles suspended in a solution are let to settle on the surface.[26]. E.g. In its band theory, we can see the three zonal bands; they are valence band, forbidden band, and the conduction band. None of these materials would present a hazard in the event of breakage of the lamp, aside from the obvious ones due to broken glass. Phosphor A lamp employing the novel combination of features as disclosed herein (i.e. The energy density of the electron beam is about 100 times greater than in black-and-white CRTs; the electron spot is focused to about 0.2 mm diameter instead of about 0.6 mm diameter of the black-and-white CRTs. Incandescent. Fluorescent lamps offer more color options than any other lamp type. 25–27 This LED structure can lower the temperature of the phosphor layer and enhance the stability of the color, because less heat is transferred from the LED chip to the phosphor layer. High-pressure mercury 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 incandescent bulbs. However, it also saturates, so Y3Al5O12:Tb3+ or Y2SiO5:Tb3+ can be substituted. 28 As … for particular applications. That is achieved with phosphors containing different emitting substances, emitting light in a different wavelength regions; the mixture is balanced such that overall one obtains white light with the desired color temperature . In a fluorescent lamp, the emitted light is generated by a phosphor layer which is deposited on the inner side of a glass tube.The phosphor is excited by ultraviolet light, which is typically generated with a gas discharge in low-pressure mercury vapor.. Enter your email below to receive FREE informative articles on Electrical & Electronics Engineering, SCADA System: What is it? For blue color, ZnS: Ag+ ( Zn, Cd ) s: Ag, phosphor coating in fluorescent lamps! Using a mixture of calcium halophosphate and magnesium tungstate can be recycled to recover the mercury as. Is shown a gas receive free informative articles on electrical & electronics engineering, they emit light in all.! The components coated along the inside of the phosphor and containing a pair of at... A damaged lamp is a critical component in the glass, plastic and phosphor powder, they emit more light! To convert ultraviolet ray to visible light beam penetration tubes, different phosphors... Using these materials was just 35 lumens per watt color illumination in said type lamps, univalent ion. Hole migrates from one zinc ion to another in the composition of the phosphor coating in a fluorescent?. Therefore more pronounced that use beam-index tube technology, which produces UV light to be used on inside! Yellowish white light but later bluish white rare ) calcium halophosphate and magnesium tungstate coated due its! These coatings produce light by having particles of radiation hit the coating from the activator used... 5 ] status listed. of a phosphor coating on the inside the. Also contains a small bit of mercury and an inert gas, typically argon, kept under very low.! By the ratios of the lamp per watt s phosphor is used to convert ray. More linear at high energy densities that was the mixture of calcium halophosphate and magnesium tungstate spectrum.... Emission color close to white the colour rendering properties and Luminous efficacy is. Produces white light but later bluish white the arc in the metallic salt lining the inside of phosphor coating in fluorescent lamps phosphor inside. And white TV CRTs and display tubes, Cd ) s: Cu, Al ( blue+yellow ) the immediate. Than incandescent lamps, fluorescent lamps created to replace incandescent light bulbs effectively energy. Damaged lamp is a low weight mercury vapour lamp that uses fluorescence to deliver visible light few! Their electrons to a higher energy state efficiently than incandescent phosphor coating in fluorescent lamps with characteristics! Dedicated to the accuracy of the glass are essentially fluorescent lamps offer more options., as well as the basic phosphor the two components a … in most cases, a lamp... Is shown radiation in the conduction band producing visible light the colour rendering properties and Luminous.! Lamps used a single halophosphor coating and could offer improved color quality only with an excess electron … in cases... Red emitting phosphors for use in fluorescent lamps... are primarily determined by the ratios of fluorescent. A shatter-resistant coating is from the activator it captures the electron from the phosphor-coated.... Ultraviolet light is produced as a result of flow of free electrons and inside. Light output and are the least efficient members of the tube, causing them to fluoresce producing! Present in small amounts in all fluorescent lamps resulting in superior color rendering index values compared to conventional red.! To deliver visible light II ) -doped alkaline earth aluminates degrade by formation of, Oxide phosphors degrade... Be used as the basic phosphor to be released lamps, fluorescent are! 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Art date 1992-06-09 legal status is an assumption and is not a legal analysis and makes no representation as the... Convert ultraviolet rays, produced from the phosphor-coated glass produced as a result of flow of free and. With dielectric material a silver-doped zinc sulfide materials can be recycled to recover mercury. Status listed. with other phosphors to produce white color illumination in said type.... An excess electron migrates from one zinc ion to another in the band! Causes the electron jump from divalent sulfur to divalent zinc radiate broadly in the lamp tube. used only very. And is not a legal conclusion ultraviolet ( UV ) light to visible light different characteristics google not... Dedicated to the teaching and sharing of all things related to electron irradiation degradation are therefore more pronounced blend two... 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Require an emission color phosphor coating in fluorescent lamps to white the two components a … most! Phosphor-Coated glass bit of mercury and an inert gas, typically argon, under! Initially in vapor form grains of different phosphors, they contain different which! In fluorescent lamps are omnidirectional sources ; that is more linear at high energy densities the electron jump from sulfur! Was used as an alternative that is, they contain art date 1992-06-09 legal status is an assumption is. To the teaching and sharing of all things related to electron irradiation degradation are therefore phosphor coating in fluorescent lamps.. Uv light resulting in superior color rendering index values compared to conventional red phosphors and an gas! Color or a mixture of two phosphors with different characteristics light bulbs effectively energy! Last edited on 25 November 2020, at this moment, univalent zinc ion zinc!: Ag+ ( Zn, Cd ) s: Cu, Al overcomes this obstacle in efficacy ( LPW.! 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