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1、摘要21LED概述・31.1LED发展历史介绍41.2LED的发展前景・52LED显示屏概述62.1LED显示屏发展经历了三个阶72.2我国LED显示屏发展现状93结束语11致谢12参考文献12LED、LED显示屏的发展历史、发展意义及前景摘要发光二极管(英语：Light-EmittingDiode,简称LED)是一种能发光的半导体电子元件。这种电子元件早在1962年出现，早期只能发出低光度的红光，Z后发展出其他单色光的版本，时至今口能发出的光已遍及可见光、红外线及紫外线，光度也提高到相当的光度。而用途也由初时作为指示灯、显示板等；随看技术的不断进步，发光二极管已被广
2、泛的应用于显示器、电视机采光装饰和照明。LED只能往一个方向导通(通电)，叫作正向偏置(正向偏压)，当电流流过时，电子与空穴在其内复合而发出单色光，这叫电致发光效应，而光线的波长、颜色跟其所采用的半导体材料种类与掺入的元素杂质有关。具有效率高、寿命长、不易破损、开关速度高、高可靠性等传统光源不及的优点。白光LED的发光效率，在近儿捻來己经有明显的提升，同时，衣每千流明的购入价格上，也因为投入帀场的厂商相互竟争的影响，而明显下降。虽然越来越多人使)IJLED照明作办公室、家具、装饰、招牌甚至路灯用途，但在技术上，LED在光电转换效率(有效照度对用电量的比值)上仍然低于新
3、型的荧光灯，是国家以后发展民用的去向！Lightemittingdiode(English:Light-EmittingDiode,referredtoasLED)isakindofsemiconductorelectroniccomponentscapableofemittinglight.Thiselectroniccomponentfirstappearedin1962,earlyonlyalow-luminosityred,afterdevelopingothermonochromaticversion,tomaketoday'slightthroughout
4、thevisiblelight,infraredandultravioletspectrophotometry,alsobeenhancedtoaconsiderablespectrophotometry.Butalsoatthebeginningoftimeasindicatorlights,displayboard;withtheprogressoftechnology,thelight-emittingdiodeshavebeenwidelyusedinmonitors,television1ightingdecorationand1ighting.LEDcan
5、onlygoinonedirectionconduction(electricity),apositivebiasiscalled(forwardbias),whenthecurrentflows,electronandholeinthecompositeandemitmonochromaticlight,thisiscalledelectroluminesceneeeffect,andthewavelengthoflight,colorandsemiconductormaterialswiththeincorporationofimpuritiesintheusin
6、gthe.Hastheadvantagesofhighefficiency,longservicelife,noteasytobedamaged,switchhastheadvantsgesofhighreliability,highspeed,lessthanthetraditionallightsource・TheluminousefficiencyofwhiteLEI),inrecentyearstherehavebeensignificantlyimproved,stthesametime,ineverythousandlumensofthepurchasep
7、rice,butalsobecauseofinvestmentfirmscompeting,droppedobviously.A1thoughmoreandmorepeopleareusingLEDlightingforofficefurniture,decoration,signs,evenstreet1ampuses,buttechnical1y,LEDinthephotoelectricconversionefficiency(theratioofeffectiveilluminationelectricity)remainsbelowthef
