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公共英语五级阅读文章《电视》公共英语五级阅读文章《电视》电视指连续动态的图像和声音转换为电子信号，并通过各种渠道传输电子信号，后再将电子信号复原为图像和声音的技术，即电视。在今天，电视已经一种十分广泛的东西。下面，通过这篇公共文章，我们来深入了解一下电视。Television——themostpervasiveandpersuasiveofmoderntechnologies,markedbyrapidchangeandgrowth——ismovingintoanewera,aneraofextraordinarysophisticationandversatility,whichpromisestoreshapeourlivesandourworld.Itisanelectronicrevolutionofsorts,madepossiblebythemarriageoftelevisionandputertechnologies.Theword"television",derivedfromitsGreek(tele:distantandLatin(visio:sightroots,canliterallybeinterpretedassightfromadistance.Verysimplyput,itworksinthisway:throughasophisticatedsystemofelectronics,televisionprovidesthecapabilityofconvertinganimage(focusedonaspecialphotoconductiveplatewithinacameraintoelectronicimpulses,whichcanbesentthroughawireorcable.Theseimpulses,whenfedintoareceiver(televisionset,canthenbeelectronicallyreconstitutedintothatsameimage.Televisionismorethanjustanelectronicsystem,however.Itisameansofexpression,aswellasavehicleformunication,andassuchbeesapowerfultoolforreachingotherhumanbeings.
Thefieldoftelevisioncanbedividedintotwocategoriesdeterminedbyitsmeansoftransmission.First,thereisbroadcasttelevision,whichreachesthemassesthroughbroad-basedairwavetransmissionoftelevisionsignals.Second,thereisnonbroadcasttelevision,whichprovidesfortheneedsofindividualsorspecificinterestgroupsthroughcontrolledtransmissiontechniques.Traditionally,televisionhasbeenamediumofthemasses.Wearemostfamiliarwithbroadcasttelevisionbecauseithasbeenwithusforaboutthirty-sevenyearsinaformsimilartowhatexiststoday.Duringthoseyears,ithasbeencontrolled,forthemostpart,bythebroadcastworks,ABC,NBC,andCBS,whohavebeenthemajorpurveyorsofnews,information,andentertainment.Thesegiantsofbroadcastinghaveactuallyshapednotonlytelevisionbutourperceptionofitaswell.Wehaveetolookuponthepicturetubeasasourceofentertainment,placingourroleinthisdynamicmediumasthepassiveviewer.以快速变化与开展为标志的最普遍、最具有影响力的一项现代技术，正在步入一个极端复杂化与多样化的新时代。这个时代承诺重新塑造我们的生活和我们的世界。这可以称得上是又一次电子革命，其关键在于电视技术与计算机技术的结合。“电视”这个词希腊语词根(tele：远和拉丁语词根(vision：景象，可以从字面上理解为远处的景象。简单说来，电视是以这种方式工作的，通过一个复杂的电子系统，电视能够将一幅图像(这幅图像被聚焦在一部摄像机内的一块特殊的光导底片上转换成能经过导线或电缆发送出去的电子脉冲信号。当这些电子脉冲信号被输入一部接收机(电视机时，就可以用电子学的.方法把脉冲信号重新恢复成同一幅图像。
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