Segment code LCD LCD tsav tsheb txoj kev Ua ntej ntawm tag nrho cov, tsis txhob xav hais tias nrog lub microcontroller tsav lub segment code screen yog DC-tsav, qhov tseeb, ntu code screen yog AC tsav, AC yog dab tsi? Rectangular yoj, sine wave thiab lwm yam. Txhua tus neeg feem ntau yuav siv cov nti tsav tsheb ua si, xws li HT1621, tab sis qee ntu ntawm lub vijtsam IO chaw nres nkoj tsawg dua, lossis yog tias qhov chaw nres nkoj IO txaus, koj tuaj yeem txuag tau tus neeg tsav tsheb sau ntawv. Lub interface nrog MCU yog yooj yim, thaum tom kawg muaj ib tug me me tsav tam sim no, tsis tshua muaj hwj chim noj, lub neej ntev, zoo nkauj zoo nkauj, ntshiab zaub, loj saib lub kaum sab xis, saj zawg zog tsav hom, thiab daim ntawv thov dav. Txawm li cas los xij, lub LCD ntawm kev tswj yog qhov nyuaj dua vim tias tus nqi DC txheeb ze ntawm LCD electrodes yuav tsum yog 0. Txwv tsis pub, lub LCD yuav oxidized yooj yim. Yog li ntawd, LCD tsis tuaj yeem tswj tau los ntawm theem teeb liab yooj yim. Hloov chaw, siv cov xwm txheej square yoj nrog qee qhov waveform. tswj.
Lub LCD zaub muaj ob hom ntawm static thiab sij hawm faib. Tus qub yog qhov yooj yim, tab sis yuav tsum tau muaj kab ntau dua; qhov tom kawg yog qhov nyuaj, tab sis xav tau cov kab tsawg dua. Ob hom no yog txiav txim los ntawm txoj kev xaiv electrode. Cov hauv qab no siv cov kua siv lead ua kua ntawm lub tshuab hluav taws xob saib ua piv txwv. Lub sij hawm siab ntawm lub sij hawm kuj tawm los yog nyob rau. Thaum tus lej siab ntawm feeb qhia tus lej digital 1 txog 5, sab saum toj thiab hauv qab kuj tawm lossis nyob rau tib lub sijhawm. Ob lub ntsiab lus tseem nyob rau lossis tawm tib lub sijhawm. Txoj kev tsav tsheb yog muab faib tsav tsheb nrog qhov sib txawv ntawm 1/2, thiab muaj 11 ntu electrodes thiab ob hom electrodes. Txawm li cas los xij, muaj qhov ua ntej rau IO analog-tsav kua siv lead ua kua zaub, uas yog, IO yuav tsum yog peb lub xeev. Vim li cas?
LCD ntuLCD npo
Nov yog qhov peb hais ua ke:
Thawj kauj ruam, qhov tseem ceeb ntawm ntu ntu code LCD: kev khiav hauj lwm voltage, lub voj voog lub luag haujlwm, kev tsis ncaj ncees piv. Peb qhov kev txwv no tseem ceeb heev thiab yuav tsum tau ua tiav.
Cov kauj ruam thib ob, txoj kev tsav tsheb: raws li txoj cai tsav tsheb ntawm LCD, tsuas yog AC voltage tuaj yeem ntxiv rau LCD pixel. Qhov sib piv ntawm LCD zaub yog txiav txim siab los ntawm kev rho tawm tus nqi hluav taws xob ntawm SEG tus pin los ntawm tus nqi hluav taws xob ntawm COM tus pin. Thaum qhov sib txawv ntawm qhov sib txawv Saturation voltage ntau dua li LCD tuaj yeem qhib lub pixel, thiab nws tuaj yeem tua lub pixel thaum lub ntsuas hluav taws xob LCD qis dua. Lub LCD hom MCU tau cia li tsim lub LCD tsav teeb liab los ntawm lub built-in LCD tsav Circuit Court. Yog li ntawd, ntev npaum li qhov chaw nres nkoj I/O tuaj yeem simulate thiab tso tawm cov teeb liab tsav. , koj tuaj yeem ua tiav cov tsav tsheb LCD.
Segment code LCD npo muaj ob lub ntsiab pins, COM, SEG, zoo ib yam li cov raj digital, tab sis lub siab sib txawv yuav tsum hloov, xws li thawj lub sijhawm yog qhov zoo 3V, ces lub sijhawm thib ob yuav tsum thim rov qab 3V Nws yog ib qho tseem ceeb uas yuav tsum tau nco ntsoov. hais tias yog ntu code LCD vaj huam sib luag yog powered los ntawm DC, lub vijtsam yuav raug nkim sij hawm ntev, yog li ceev faj. Cia peb xav txog yuav ua li cas simulate COM chaw nres nkoj waveform. Siv 1/4D, 1/2B ua piv txwv:
Nyob rau tib lub sijhawm, peb yuav tsum xyuam xim rau, thaum lub COM tso zis siab, yog tias lub vijtsam yog nyob rau, SEG yuav tso zis qis, ces thaum lub COM tso zis qis, SEG yuav tso zis siab, xyuas kom meej tias lub siab sib txawv ntawm COM thiab SEG yog ntau dua 1/2B kev khiav hauj lwm voltage Nws tuaj yeem tshwm sim
Thaum SEG qib rov qab nrog COM qib, tsav lub ntu LCD yog qhov ua tiav.
Tshooj cai lcd kev paub yooj yim
Cov kua siv lead ua kua yog cov zaub tsis pom kev, nws tsis tuaj yeem tawm lub teeb, tsuas yog siv lub teeb pom kev zoo xwb. Nws pom tsuas yog me me ntawm lub zog rau tus qauv lossis tus cwj pwm. Vim tias siv hluav taws xob tsawg thiab kev siv me me, LCD tau dhau los ua txoj hauv kev zoo dua.
Cov khoom siv ua kua siv lead ua kua siv hauv cov kua siv lead ua kua yog cov khoom siv organic uas muaj cov khoom ua kua thiab cov khoom. Nws cov qauv zoo li tus pas nrig feem ntau yog txheej txheem sib luag hauv cov kua siv lead ua kua cell, tab sis nws tuaj yeem hloov nws txoj kev sib dhos raws li qhov kev txiav txim ntawm qhov hluav taws xob.
Rau qhov zoo TN-LCD, thaum tsis muaj qhov hluav taws xob siv rau electrode, LCD yog nyob rau hauv lub xeev "OFF", thiab lub teeb lub zog kis tau los ntawm LCD hauv lub xeev dawb; Thaum qhov hluav taws xob tau siv rau lub electrode, lub LCD yog nyob rau hauv lub xeev "ON", qhov ntev axis kev taw qhia ntawm cov kua siv lead ua kua molecules. Teem caij nyob rau hauv cov kev taw qhia ntawm hluav taws xob teb, lub teeb tsis tuaj yeem dhau los ntawm LCD thiab zoo li dub. Xaiv qhov kev siv hluav taws xob hla cov electrodes, cov qauv sib txawv tuaj yeem tshwm sim.
Rau STN-LCD, lub kaum sab xis ntawm cov kua siv lead ua kua yog loj dua, yog li qhov sib piv zoo dua thiab pom lub kaum sab xis dav dua. STN-LCD yog raws li birefringence txoj kev xav, nws cov xim yooj yim feem ntau yog daj-ntsuab, font xiav, daj ntsuab qauv. Thaum siv cov polarizer ntshav, lub hauv paus xim tig grey los ua grey pwm. Thaum siv cov yeeb yaj kiab polarizing nrog cov zaj duab xis them nyiaj, lub hauv paus xim yuav dhau los ua xim dawb. Lub sijhawm no, STN dhau los ua hom dub thiab dawb, uas yog, FSTN. Hom saum toj no ntawm lub polarizer tig 90 degree, uas yog, nws dhau los ua hom xiav, thiab cov nyhuv yuav zoo dua.
Raws li tuaj yeem pom los ntawm daim duab, cov kua siv lead ua kua yog cov kua siv lead ua kua cell ua los ntawm sab saud thiab qis dua ob nplooj ntawv ntawm cov iav conductive. Lub xovtooj ntawm tes yog ntim nrog cov kua muaju, thiab qhov chaw nruab nrab yog ntim nrog cov khoom sib khi-ib lub hnab yas (feem ntau yog epoxy resin). Ob sab ntawm lub cell raug kaw. Polarizer txuas.
Lub sijhawm nruab nrab ntawm cov iav saum toj thiab qis hauv cov kua siv lead ua kua cell, uas feem ntau hu ua cell thickness, feem ntau yog ob peb micrometers (tus txiv neej txoj kab uas hla yog kaum ntawm micrometers). Sab hauv ntawm daim iav sab sauv thiab sab qis, sib haum rau cov qauv qauv, yog coated nrog pob tshab conductive oxide-tin oxide (ITO) conductive zaj duab xis, piv txwv li, ib qho screen electrode. Lub luag haujlwm ntawm electrode yog tsuas yog ua kom cov hluav taws xob sab nraud los ntawm nws mus rau cov kua siv lead ua kua.
Tag nrho cov chaw tso saib nyob rau hauv lub iav pane nyob rau hauv cov kua siv lead ua cell yog them nrog ib tug alignment txheej. Lub luag haujlwm ntawm cov txheej txheem sib dhos yog ua kom cov kua siv lead ua kua molecules nyob rau hauv ib qho kev taw qhia tshwj xeeb. Cov txheej txheem kev sib raug zoo no feem ntau yog txheej nyias nyias ntawm cov organic polymer thiab kho los ntawm kev txhuam; Nws tseem tuaj yeem npaj tau los ntawm lub tshuab nqus tsev vacuum ntawm silicon oxide zaj duab xis ntawm lub kaum sab xis ntawm lub iav nto. .
Lub TN-hom kua siv lead ua kua zaub yog sau nrog ib tug zoo nematic kua siv lead ua. Kev taw qhia ntawm cov kua siv lead ua kua molecules yog xws li cov pas nrig ntev-hom kua siv lead ua kua molecules tau teem rau hauv ib qho kev taw qhia ruaj khov mus rau lub iav nto, thiab cov kev taw qhia ntawm qhov ntev axis ntawm cov molecules yog raws li cov kev taw qhia kev kho mob. Cov kev taw qhia ntawm cov iav sab sauv thiab sab qis yog perpendicular mus rau ib leeg, yog li ntawd qhov kev taw qhia ntawm cov kua siv lead ua kua molecules hauv lub thawv yog maj mam distorted nyob rau hauv cov kev taw qhia perpendicular mus rau saum npoo ntawm daim iav, thiab daim ntawv iav yog twisted los ntawm 90 degree ntawm daim iav sab sauv mus rau daim iav qis (saib daim duab hauv qab). Nws yog lub hauv paus chiv keeb ntawm lub npe twisted nematic LCD.
Qhov tseeb, cov kua siv lead ua kua molecules nyob ze rau ntawm lub iav saum npoo tsis yog tag nrho mus rau lub iav nto, tab sis yog nyob ntawm ib lub kaum ntse ntse rau nws. Lub kaum sab xis no yog hu ua lub kaum sab xis pretilt, uas feem ntau yog 1 degree ~ 2 degree.
Ob lub polarizers yog txuas mus rau sab nrauv ntawm daim iav hauv cov kua siv lead ua kua cell, thiab cov polarization axes ntawm ob lub polarizers yog sib npaug rau ib leeg (qhov feem ntau yog hom dub yog dawb ntawm cov keeb kwm dub) los yog orthogonal rau ib leeg. (ib hom dawb ib txwm yog ib lub cim dub rau ntawm keeb kwm dawb). Kev taw qhia kev taw qhia ntawm qhov chaw ntawm cov kua siv lead ua kua cell yog parallel lossis perpendicular rau ib leeg. Polarizers feem ntau ua tiav los ntawm cov yeeb yaj kiab yas polymer nyob rau hauv qee yam txheej txheem.
Feem ntau ntawm qhov peb feem ntau pom yog rov qab-hom kua siv lead ua zaub, uas muaj ib daim ntawv qhia qab qab polarizer. Nyob rau hauv no txoj kev, lub teeb yog xwm txheej thiab pom nyob rau tib sab ntawm lub cell.
Cov txheej txheem pom
LCD muaj ntau txoj kev tso saib: reflective, transmissive thiab transflective. Ib daim phaj reflective yog txuas tom qab polarizer hauv qab ntawm qhov pom ntawm LCD. Nws feem ntau yog siv sab nraum zoov thiab hauv chaw ua haujlwm zoo. Hauv qab polarizer ntawm transmissive LCD yog transmissive polarizer, uas yuav tsum tau siv tas li ntawm lub teeb rov qab, thiab feem ntau yog siv nyob rau hauv qhov chaw tsis zoo. Lub transflective LCD yog nruab nrab ntawm ob saum toj no. Cov polarizer hauv qab tuaj yeem cuam tshuam lub teeb thiab feem ntau muaj lub teeb rov qab. Thaum lub teeb pom kev zoo, lub teeb rov qab tuaj yeem muab tua. Thaum lub teeb tsis zoo, lub teeb rov qab tuaj yeem teeb siv lub LCD.
LCD zaub kuj tau muab faib ua qhov zoo thiab tsis zoo. Cov LCDs zoo muaj cov tsiaj ntawv dub ntawm cov keeb kwm dawb thiab pom zoo tshaj plaws hauv LCDs pom thiab transflective; LCDs tsis zoo yog pom nyob rau hauv dub rau dawb thiab feem ntau yog siv nyob rau hauv transmissive LCDs. Nrog lub teeb rov qab, cov fonts meej thiab yooj yim nyeem.
Backlight
Transmissive thiab semi-transmissive LCDs feem ntau yuav tsum tau ntxiv qhov chaw teeb pom kev zoo. Qhov chaw ntawm lub teeb pom kev zoo raws li qhov xwm txheej hauv qab no qhia txog ntau qhov chaw teeb pom kev zoo:
Electroluminescence (EL): EL backlights yog nyias, lub teeb yuag, thiab emit lub teeb sib npaug. Nws tuaj yeem siv rau hauv cov xim sib txawv, tab sis nws yog feem ntau siv hauv LCD dawb backlights. EL backlight fais fab tuag yog tsawg, tsuas yog qhov voltage ntawm 80-100VAC, los ntawm transformer mus rau 5V, 12V lossis 24VDC hloov dua siab tshiab. EL backlight muaj ib nrab-lub neej ntawm li 2000-3000 teev.
Lub teeb Emitting Diodes (LEDs): LED backlights yog siv rau cov cim hom modules. Lub neej ntev dua EL (tsawg kawg 5000 teev), lub teeb muaj zog dua, tab sis siv zog ntau dua. Raws li cov khoom siv hauv lub xeev, nws siv 5VDC ncaj qha. Lub LCD feem ntau teem ncaj nraim tom qab lub LCD, thiab lub thickness yog nce los ntawm 5 hli. LEDs tuaj yeem tso cov xim sib txawv ntawm lub teeb, feem ntau yog lub teeb daj-ntsuab.
Txias Cathode Fluorescent Teeb (CCFL): Lub CCFL tuaj yeem muab lub zog qis thiab lub teeb ci dawb. Nws emits lub teeb los ntawm ib tug txias cathode fluorescent raj, thiab lub teeb yog sib npaug zos rau hauv lub qhov rais cheeb tsam los ntawm ib tug diffuser. Sab nraub qaum muaj qhov me me thiab siv hluav taws xob tsawg, tab sis CCFL xav tau lub tshuab hloov pauv los muab 270-300VAC. Nws yog tsuas yog siv rau cov duab LCDs thiab muaj lub neej ntawm 10, 000 txog 15, 000 teev.
TN thiab STN yog ob hom kua siv lead ua kua. Cov kua siv lead ua kua ntawm TN zaub yog twisted los ntawm 90 [deg.] hauv cov kua siv lead ua kua cell thiab feem ntau yog siv rau cov khoom qis-channel LCD.
Cov kua siv lead ua kua tso tawm los ntawm STN yog twisted los ntawm 180 degree mus rau 360 degree hauv cov kua siv lead ua kua cell. Qhov loj dua qhov twist lub kaum ntse ntse, qhov steeper lub electro-optical nkhaus thiab ze rau V thiab V tawm qhov tseem ceeb. Nws tuaj yeem siv rau kev tsim khoom ntawm 32 lossis ntau dua LCD khoom.
LCD saib
Lub ntsiab lus ntawm kev pom tsuas yog lub kaum sab xis uas cov qauv pom tau pom meej. Nws yog txiav txim siab los ntawm cov kev taw qhia ntawm cov txheej txheem sib dhos thiab tsis tuaj yeem hloov pauv los ntawm kev tig lub polarizer. Lub kaum sab xis ntawm kev pom yog muaj npe tom qab teev tes, xws li 6:00 saib lub kaum sab xis, 12:00 saib lub kaum ntse ntse, thiab lwm yam. Lub 6:00 saib lub kaum sab xis txhais tau hais tias lub LCD nyob rau hauv cheeb tsam los ntawm 6 teev mus rau qhov qub kev taw qhia ntawm tes tes yog zoo tagnrho; lub 12:00 saib lub kaum sab xis yog qhov zoo tagnrho tso saib ntawm 12 teev pob kws mus rau qhov qub kev taw qhia.
Lub LCD saib lub kaum sab xis yog txiav txim los ntawm txoj hauj lwm ntawm LCD zaub ntawm lub ntsuas. Piv txwv li, lub tshuab xam zauv feem ntau yog muab tso rau ntawm lub rooj lossis ntawm tes, thiab lub LCD yog ua los ntawm 6:00 saib lub kaum ntse ntse. Qee cov twj paj nruag muaj lub vijtsam LCD nyob hauv qab kab ntawm qhov pom ntawm tib neeg lub qhov muag thiab feem ntau ua rau ntawm qhov pom ntawm 12:00. Lub moos ntawm lub tsheb feem ntau yog ntsia rau sab xis ntawm tus neeg tsav tsheb, ua qhov pom qhov zoo tshaj plaws ntawm 9:00.
