Scanners me tub koj lub neej hauv lub ntiaj teb digital ...
Yog, muaj ntau hom scanners, tiam sis feem ntau ntawm lawv (tshwj tsis yog, kab tias, lub nruas luam yeeb siv hauv kev lag luam) "ntes" cov ntaub ntawv-muab nws cov ntaub ntawv, cov duab lag luam, lossis duab, nrog rau cov duab, , thiab negatives-tib txoj kev, uas yog lub ntsiab lus ntawm qhov tsab xov xwm no. Li cas tus scanner siv ib daim ntawv phab, luam tawm nws cov ntsiab lus, thiab tom qab ntawd mam muab cov ntaub ntawv xa mus rau lub tshuab computer uas koj thiab kuv tuaj yeem ua nrog rau thaum peb thov?
Txheeb Cov Ntaus Nrig Qiv Ntaus (CCD)
Thaum lub tshuab luam yeeb ua ntau yam, xws li tsom iav, lo ntsiab muag, tsheb, thiab ntau dua. Nyob rau feem ntau ntawm cov niaj hnub no, li, tus tub ntxhais tivthaiv yog tus nqi them ua ke (CCD). Ib qho khoom siv ntawm lub teeb ntom teeb uas hloov cov duab fais fab (lub teeb) rau electrons, lossis hluav taws xob, cov duab no feem ntau yog cov duab .
Photosites muaj kev nkag siab rau lub teeb; qhov kaj ci zog qhov hluav taws xob ntau dua. Nyob ntawm tus qauv ntawm lub tshuab luam yeeb, cov duab scanned los yog cov ntawv pom nws txoj kev mus rau CCD array los ntawm kab ntsiab muag, cov ntxaij lim dej, thiab cov iav. Cov khoom no tsim cov luam taub hau . Thaum lub sijhawm sojntsuam, lub taub hau luam yeeb yog dhau ntawm lub hom phiaj (tus kwv tau muab luam tawm).
Nyob ntawm lub tshuab luam ntawv, qee qhov yog ib qho-dhau thiab qee yam muaj peb kis, uas txhais tau hais tias lawv tuaj nqa cov khoom ua luam ntawm ob qho los sis peb, feem. Nyob rau ntawm peb lub xeem scanner, txhua kis pib xaiv ib qho txawv xim (xim liab, ntsuab, lossis xiav), thiab tom qab ntawd software reassembles peb RGB xim raws, ua khoom qub.
Nta, feem ntau scanners yog ib leeg-dhau, nrog lub lens ua qhov kev sib cais ntawm peb cov xim raws, tsis yog tus neeg siv ua qhov laj lim tswv yim.
Hu rau Image Sensor
Ib qho, tsis tshua muaj nuj nqi pom kev lag luam mus nce av hauv av tsis ntev los no yog hu rau duab sensor (CIS). CIS hloov lub CCD array, nrog nws cov iav, cov ntxaij lim dej, teeb, thiab lo ntsiab muag, nrog cov kab liab, ntsuab, thiab xiav (RGB) lub teeb emitting diodes (LEDs). Ntawm no, duab sensor mechanism muaj 300 mus rau 600 sensors uas muaj siab dav ntawm lub platen los yog lub tshuab ntaus thwj rau. Thaum tus duab raug scanned, cov LEDs muab lub teeb dawb, pom cov duab, uas yog ces yuav los ntawm cov sensors.
CIS scanners tsis feem ntau muab cov theem zoo thiab kev daws teeb meem los ntawm CCD-based machines, tab sis, ces tus qub yog feem ntau thinner, sib zog, thiab pheej yig dua.
Kev daws teeb meem thiab xim qhov tob
Cov kev txiav txim siab twg koj yuav tsum luam theej yog nyob ntawm seb koj npaj yuav siv daim duab. Cov computer monitors, ntsiav tshuaj, thiab smartphones yeej tsis tuaj yeem tso saib tau tshaj li ntawm 72 dots ib nti (dpi), nrog HD monitors txhawb nqa 96dpi. Qhov tsuas yog qhov uas tshwm sim thaum koj luam cov duab ntawm ntau dua li qhov nws pom tau ntawm, cov ntaub ntawv extraneous no tsuas tossed tawm, uas, tau kawg, yuav siv sij hawm.
Cov duab nyob rau hauv koj cov ntawv nyeem high-end thiab lwm yam, ntawm qhov tod tes, yog ib zaj dab neeg sib txawv. Rau qhov zoo tshaj plaws ua tau, koj yuav tsum tau luam roj rau tsawg kawg 300dpi, thiab siab dua, ntau dua, yog tias ua tau-tsuas yog thaum koj xav tau tus duab hauv qhov kev teeb tsa.
Qhov tob xim qhia txog cov xim ntawm cov duab (lossis luam theej duab). Cov possibilities 8-ntsis, 16-ntsis, 24-ntsis, 36-ntsis, 48-ntsis, thiab 64-ntsis, nrog rau tus qub, 8-ntsis, txhawb 256 xim lossis ntxoov grey thiab 64-ntsis txhawb trillions ntawm xim-deb ntau tshaj li cov tib neeg lub qhov muag yuav pom.
Obviously, nyob rau hauv vim li cas, kev daws teeb meem loj thiab sib sib zog nqus xim depths txhim khu kev soj ntsuam zoo, vim li cas, tau kawg. Cov xim, qhov zoo, thiab qhov kev nthuav dav yuav tsum muaj ua ntej koj luam theej duab. Tsis muaj teeb meem zoo li cas koj lub tshuab luam ntawv, nws tuaj yeem ua txuj ci tseem ceeb.