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Phosphor and how it related to LED

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Phosphorandhowitrelatedto LED

Phosphoris a substancethat displaysthephenomenonof luminescence.Broadly itincludesfluorescent andphosphorescentmaterialsthatdepictdecayin brightnessover a fewnumbersof seconds.Materialsthat havean elementof phosphor is referredto as phosphorescent(Allen, 2012). Thesematerialsareappliedtheproductionof displayscreens,cathode raytubeandwhite LEDs. In chemicalterms,phosphordenotesa groupof transitional metalandis designatedby letter.Phosphor compoundshavethree maindistinctivefeatures:

Energytheyneedto be energized

Amountof timetheygrowafter thecompoundis energized

Colorof thevisiblelighttheyemit

Phosphorisusedin theproductionof white lightemittingdiodes (LEDs) forthemanufactureof LCD (liquidcrystaldisplay)backlighting units.Theseare madethrough coatingbluelightemittingdiodes with yellowandothercompoundsof rareearths to createwhite emission(Allen, 2012). LEDphosphor isthenusedin thebacklighting of technological gadgetssuchas tablets,LEDtelevisionandsmartphones.Materialsare capableof emittinglightthrough luminescenceorincandescence.Emissionthrough incandescenceis whereallatomsin theelementare capableof radiatinglightwhileluminescenceis whereonlya smallfractionof theatomsemitlight.

Asaforementioned phosphors displaylightthrough luminescencebutsmallamountsof impuritiesare addedto increaseemissionof light.Theportionof theatomthatemits lightis referredto as emissioncenterandthewavelength of lightemittedispeggedon theatomandthenature(impurities)of materialsthatsurround it(Allen, 2012). Screensmadeof LCD that is coatedwith a thinlayerof LEDconsumelowerpowerthan thatmadeof LCD alone.WhenWhite lightemittingdiodes producinga combinationof bluelightfrom aLED,andyellowlightfrom thephosphor, the white lightsproducedby thiscombinationprovidesampleilluminationmorethan incandescentbulbs, consumeslower quantities of powerand lastslonger.

WorksCited

Allen,G.LEDLighting Driving Demand for New Phosphors.NanoMarkets, LC. 2012.