Txawm hais tias CCFL backlighting tau siv dav rau lub sijhawm ntev, nws muaj ntau yam tsis zoo. Lub caij no, LED, raws li lub teeb pom kev zoo, feem ntau piques xav paub txog nws txoj haujlwm ua haujlwm. Yog li, dab tsi yog qhov kev txwv ntawm cov tsoos CCFL backlighting? Thiab LED ua haujlwm li cas? Kab lus no yuav teb cov lus nug no ib los ntawm ib qho.
Tam sim no, feem ntau lub ntsiab LCDs siv CCFL (Cold Cathode Fluorescent Lamps) rau lawv cov teeb pom kev zoo, uas muaj lub neej luv luv -qhov tsis zoo ntawm LCDs. Hmoov zoo, tam sim no tau pom ib tus neeg ua tiav tam sim no -LED.
Cov teeb meem ntawm Traditional CCFL Backlighting
Ua ntej delving rau hauv LED backlighting technology, nws yog tsim nyog los nkag siab txog cov teeb meem nrog tam sim no backlighting technology. Peb paub tias kua siv lead ua kua yog ib yam khoom nruab nrab ntawm cov kua thiab siv lead ua. Qhov zoo tshaj plaws ntawm cov kua siv lead ua kua yog tias nws cov qauv molecular hloov tau los ntawm hluav taws xob tam sim no; siv cov hluav taws xob sib txawv rau cov kua siv lead ua kua tuaj yeem tswj cov teeb pom kev zoo, yog li nthuav tawm ntau yam duab. Txawm li cas los xij, cov kua siv lead ua kua nws tus kheej tsis tawm lub teeb, yog li txhua lub LCD yuav tsum muaj teeb pom kev zoo. Tam sim no, yuav luag tag nrho LCD backlights yog CCFL (Cold Cathode Fluorescent Teeb).
Vim tias lub teeb txias cathode fluorescent teeb (CCFLs) tsis yog qhov chaw teeb pom kev zoo, LCD backlight modules xav tau ntau lub koom haum pab xws li diffusers, lub teeb qhia, thiab cov reflectors kom ua tau raws li cov teeb pom kev zoo. Txawm li cas los xij, kev ua tiav tib lub teeb pom kev zoo ib yam li CRT tseem nyuaj heev. Feem ntau cov LCDs pom qhov sib txawv ntawm qhov ci ntsa iab ntawm cov npoo ntawm lub vijtsam thiab qhov nruab nrab thaum pom cov duab dawb lossis tag nrho cov duab dub.
Dhau li ntawm cov qauv nyuaj thiab qhov tsis zoo ntawm lub teeb ci tsis zoo, siv CCFLs raws li LCD backlights nthuav tawm lwm qhov teeb meem loj - lub neej luv. Qhov ci ntawm feem ntau CCFL backlights txo qis tom qab 2-3 xyoos ntawm kev siv (lifespan yog 15,000-25,000 teev). Ntau lub LCDs (tshwj xeeb tshaj yog cov ntxaij vab tshaus laptop) qhia yellowing thiab dimming tom qab ob peb xyoos ntawm kev siv, precisely vim lub luv luv lifespan ntawm CCFLs.
Tsis tas li ntawd, vim CCFL backlights yuav tsum muaj cov khoom siv kho qhov muag xws li diffusers thiab reflectors, qhov loj ntawm LCDs tsis tuaj yeem txo ntxiv. Hais txog kev siv hluav taws xob, LCDs siv CCFLs li backlights kuj tsis txaus siab; 14-nti LCD's CCFL backlight feem ntau siv 20W lossis ntau dua ntawm lub zog. Qhov no yuav kuaj lub roj teeb lub neej ntawm cov laptops thiab cov khoom siv nqa tau hnyav.
Txhawm rau hais txog cov kev txwv ntawm CCFLs, yuav luag txhua lub tuam txhab LCD pib tshawb nrhiav cov kua siv lead ua kua zoo tshaj. LEDs, nrog rau lawv cov ultra-kev siv hluav taws xob tsawg, lub neej ntev heev, thiab cov qauv yooj yim, tau txais txiaj ntsig sai ntawm cov tuam txhab LCD. Yog li dab tsi yog LED? Dab tsi ua rau nws tshwj xeeb?
Qhov tseeb, LEDs (Lub Teeb Emitting Diodes) tsis yog txiav- thev naus laus zis; lawv muaj nyob rau hauv peb lub neej txhua hnub: cov yeeb yuj billboards, taw qhia teeb ntawm ntau yam xim ntawm cov khoom siv hauv tsev, backlighting rau cov xov tooj ntawm tes nyees khawm, tsheb headlights, thiab lwm yam, tag nrho cov siv LEDs raws li lub teeb qhov chaw.
Txij li thaum nws tsim nyob rau xyoo 1960, LEDs tau suav tias yog qhov kawg ntawm cov raj fluorescent thiab lub teeb, nrog qee tus txawm ntseeg tias LEDs yuav coj mus rau lub sijhawm tshiab ntawm teeb pom kev zoo, thaum kawg tshwm sim hauv txhua qhov xwm txheej xav tau kev teeb pom kev zoo. Lub hauv paus ntsiab lus ua haujlwm ntawm LEDs yog txawv kiag li ntawm cov teeb pom kev zoo thiab fluorescent; LEDs yog qhov tseem ceeb ntawm cov khoom siv semiconductor.
Lub hauv paus ntawm LED yog ib nti uas muaj P-hom thiab N- hom semiconductors. Ntawm qhov sib txuas ntawm cov khoom siv hluav taws xob no yog ib txheej nyias nyias nrog cov khoom siv tshwj xeeb, feem ntau hu ua PN junction (PN junction transistor). PN hlws ris tiv thaiv qhov sib txawv ntawm cov neeg nqa khoom feem ntau hauv ob qho tib si semiconductors. Thaum ib qho hluav taws xob xa mus rau PN kev sib tshuam, tam sim no ntws los ntawm anode mus rau cathode. Hauv kev sib tshuam PN, cov neeg tsawg thiab cov neeg nqa khoom feem ntau rov ua dua, thiab lub zog ntau dhau raug tso tawm raws li lub teeb. LEDs ua tiav electro- hloov kho qhov muag raws li txoj cai no. Nyob ntawm seb lub cev muaj zog ntawm cov khoom siv semiconductor, LEDs tuaj yeem tawm lub teeb ntawm qhov sib txawv wavelengths thiab xim, xws li ultraviolet mus rau infrared.
Nws yog qhov tseeb vim yog lub teeb ci semiconductor- tawm txoj hauv kev ntawm LEDs uas lawv muaj ntau yam zoo xws li kev ua haujlwm siab, kev ua neej ntev, thiab kev phooj ywg ib puag ncig, ua rau lawv zoo tagnrho hloov rau CCFLs.
