Cov Ntsiab Cai
Siv cov cuab yeej photosensitive, lub teeb pom kev pom tau hloov mus rau hauv cov teeb liab hluav taws xob. Cov teeb liab hluav taws xob no yog tom qab ntawd hloov mus rau hauv cov teeb liab digital los ntawm analog - mus rau -digital (A/D) converter thiab xa mus rau lub computer.
Photoelectric Hloov Cheebtsam
Cov khoom siv uas ua rau kev hloov pauv photoelectric yog cov khoom siv photosensitive, uas yog lub hauv paus ntawm lub scanner. Nws cov yam ntxwv hloov pauv photoelectric, xws li cov lus teb spectral, lub teeb ruaj khov, rhiab heev, thiab suab nrov, yog qhov tseem ceeb rau kev xa cov duab duab.
① CCD (Chaw Coupled Device)
Lub npe Suav rau CCD yog Charge Coupled Device. Zoo ib yam li cov khoom siv hluav taws xob sib xyaw ua ke, nws ua ke ntau txhiab tus phototransistors ntawm ib leeg siv lead ua silicon. Cov phototransistors no tau teem rau hauv peb kab, txhua tus them los ntawm cov xim liab, ntsuab, thiab xiav xim lim, yog li ua tiav cov xim scanning. Thaum illuminated, cov phototransistors tsim ib tug tam sim no, uas yog amplified thiab tso zis. CCD scanner thev naus laus zis tau loj hlob muaj txiaj ntsig ntau xyoo thiab yog thawj cov duab zoo nkauj siv hauv cov tshuab luam ntawv loj hauv khw.
Qhov zoo ntawm CCDs yog: cov duab zoo, qhov tob txaus ntawm daim teb, thiab muaj peev xwm luam theej duab cov khoom tsis sib xws; thiab qhov kub tsis tshua muaj coefficient, txhais tau hais tias kev hloov pauv ntawm qhov kub thiab txias tsis zoo rau kev ua haujlwm dav dav. Qhov tsis zoo ntawm CCDs muaj xws li: cov xau tseem ceeb tam sim no muaj nyob nruab nrab ntawm ntau txhiab tus phototransistors uas tsim CCD vim lawv qhov ze ze (micrometer-theem), thiab cuam tshuam los ntawm cov teeb liab ntawm txhua chav tsev photosensitive txo qhov tseeb meej ntawm lub scanner; kev siv cov iav thiab lo ntsiab muag qhia txog xim sib txawv thiab aberrations, yuav tsum tau kho software; thiab qhov kev xav tau rau lub tshuab kho qhov muag ua rau nws nyuaj rau miniaturize lub scanner.
② CIS (hu rau duab Sensor)
CIS sawv cev rau Kev Sib cuag Duab Sensor. Nws siv kev sib cuag - hom photosensitive ntsiab (photosensitive sensors) rau lub teeb pom kev. Ntawm qhov tob ntawm 1mm-2mm hauv qab lub scanning platform, 300-600 liab, ntsuab, thiab xiav LEDs (lub teeb-emitting diodes) nruj nreem teem ua ke, tsim ib lub teeb dawb. Qhov no hloov cov txheej txheem nyuaj ntawm CCD scanners, xws li CCD array, lo ntsiab muag, fluorescent raj, thiab txias cathode ray raj, hloov kho qhov muag -mechanical- electronics kev koom ua ke ntawm CCD scanner rau hauv kev sib koom ua ke ntawm cov tshuab hluav taws xob ntawm CIS scanner. Scanners ua nrog CIS thev naus laus zis muaj qhov zoo xws li qhov me me, lub teeb yuag, thiab cov nqi tsim khoom tsawg. Txawm li cas los xij, CIS thev naus laus zis kuj tseem muaj qhov tsis txaus, feem ntau tsis muaj peev xwm los tsim cov kev daws teeb meem siab thiab qhov scanning qeeb qeeb.
Lub teeb Source
Lub teeb pom kev zoo yog qhov tseem ceeb rau cov tshuab luam ntawv vim tias txhua lub teeb pom los ntawm cov teeb pom kev zoo los ntawm lub scanner lub teeb. Cov xim tsis huv lossis xim- qhov chaw teeb pom kev ncaj ncees cuam tshuam ncaj qha rau cov txiaj ntsig scanning. Piv txwv li, tej zaum koj yuav pom ib daim khaub ncaws uas koj nyiam hauv khw, tab sis thaum koj mus txog tsev, cov xim zoo li txawv ntawm qhov koj pom hauv khw. Qhov no yog vim lub teeb ci tau hloov pauv, ua rau pom qhov txawv txav.
Analog -rau-digital (A/D) converter
Ib qho A/D converter hloov pauv hloov pauv tsis tu ncua analog teeb liab rau hauv cov teeb liab tsis sib xws. Nws lub luag haujlwm tseem ceeb yog hloov pauv qhov tau txais analog voltages rau hauv cov txiaj ntsig digital uas sawv cev cov xim lossis cov txiaj ntsig grey. Cov ntsuas kev ua haujlwm tseem ceeb suav nrog kev hloov pauv qhov tseeb, lub sijhawm hloov pauv, thiab cov tswv yim tsis kam.
