最重要的發(fā)明電燈

Themostimportantinvention----LightIntroductionTheFirstElectricLightMadein1809byHunphryDavy,thisiscalledtheelectricarc.LateTheAmericanCharlesFranciesBrush

manufacturedsomecarbonarcs.TheInventor

ThomasEdisonexperimentedwiththousandsofdifferentmaterials,eventuallyproducedabulbthatcouldglowforover1500hours.漢弗萊·戴維爵士（法拉第旳老師）[ɑ?k]電弧manufactured[,m?nj?'f?kt??]制造，加工（manufacture旳過去式）carbonarcs[電]碳弧bulb[b?lb]電燈泡Therearethreekindsoflight.1.Incandescentlamp(白熾燈)：

a.Incandescentlamp（白熾燈）

b.Tungstenhalogenlamp（鹵鎢燈）

c.Halogenlamp（鹵素?zé)簦?.....2.Highintensitydischargelamp-HID（氣體放電燈）

a.Fluorescentlamp（熒光燈）

b.Sodiumlamp（鈉燈）

c.Metalhalidelamp（金屬鹵化物燈）......3.Others.

a.ElectrodelessLamp（高頻無極燈）

b.LightEmittingDiode（發(fā)光二極管）......

Intheearly19thcentury，aBritishchemistmadethefirstarclampintheworldbyusing2023cells(電池）and2carbonrods.Butthiskindoflightistoostrong，itcannotbeusedinthehousebutonlyinthestreet.In1879

ByThomasEdison--anAmericaninventorThetemperatureofthefilament:3000℃Averagelifespan:1000hIt'salampwhichranksfirstintheproductionoftheworld.Butmanycountriesaretryingtostopusingit,becauseofitsheavypollution.Incandescentlamp（白熾燈）filament

['f?l?m?nt]燈絲lifespan

壽命ComparetoIncandescent

lamp,thiskindoflamphaslongerlifespan(4000h)andhigher

lightefficiency.ItItisoftenusedinthemeetingroom,theexhibitionhallandthestage.TungstenHalogenLamp（鹵鎢燈）lightefficiency

光效率FluorescentLamp（熒光燈，俗稱日光燈）Longlifespan:2500h~3500hHighlightefficiencyGoodcolorrenderingThetemperatureofthefilament:≤1000℃colorrendering顯色性SodiumLamp(鈉燈)Thehighestlightefficiency.FogpermeabilityLifespan:20230hBeusedinroads,airports,terminals,highways,etc.Fogpermeability

透霧性ElectrodelessLamp（高頻無極燈）Verylonglifespan:40000h~80000hEnergysavingBrighter

So,itisoftenusedinsomeplaceswhichhavehigherrequirementsforsafety.Suchastunnels,subwaystationsandfactories.tunnels隧道LightEmittingDiode（發(fā)光二極管）Samefeaturesaselectrodelesslamp,butmoreenergysaving.Itissecurewhenitworkunderthelowthermalvoltage.Andit'ssurfacetemperaturelessthan60℃.low

thermalvoltage

低熱電壓