LED grey nplai kuj tuaj yeem raug xa mus rau qhov ci ci LED. Grey theem kuj hu ua ib nrab-tone. Nws yog tsuas yog siv los xa cov duab. Muaj peb txoj hauv kev ntawm 16, 32, thiab 64 qib. Nws siv cov txheej txheem matrix los ua cov pixels ntawm cov ntaub ntawv mus rau 16, 32, thiab 64 qib. Hierarchy ua kom cov duab kis tau yooj yim dua. Txawm hais tias nws yog ib qho xim, ob-xim, lossis peb-xim npo, los tso saib cov duab lossis cov yeeb yaj kiab, nws yog qhov yuav tsum tau kho qhov luminous grey theem ntawm txhua LED uas ua rau lub pixel. Qhov zoo ntawm kev hloov kho yog qhov peb feem ntau hu ua qib grey.
Muaj ob txoj hauv kev los tswj cov nplai grey ntawm LEDs: ib qho yog hloov cov tam sim no ntws los ntawm, thiab lwm qhov yog pulse width modulation. 1. Hloov tam sim no ntws los ntawm LED. Feem ntau, cov raj LED tso cai rau kev ua haujlwm tsis tu ncua ntawm li 20 mA. Tsuas yog rau qhov saturation ntawm liab LEDs, lub grey scale ntawm lwm LEDs yog feem ntau proportional rau tam sim no ntws; Lwm txoj hauv kev yog siv qhov pom kev inertia ntawm tib neeg lub qhov muag thiab siv mem tes dav. Txoj kev hloov kho yog siv los ua kom tau txais kev tswj hwm grey, uas yog, lub teeb mem tes dav (uas yog, lub luag haujlwm lub voj voog) hloov pauv ib ntus. Ntev npaum li lub sij hawm rov qab teeb pom kev zoo yog luv txaus (uas yog, qhov hloov tshiab zaus yog siab txaus), tib neeg lub qhov muag yuav tsis hnov lub teeb-emitting pixels. Jitter. Vim tias pulse width modulation yog tsim nyog rau kev tswj digital, niaj hnub no thaum microcomputers feem ntau siv los muab cov ntsiab lus ntawm LED, yuav luag tag nrho cov ntxaij vab tshaus LED siv pulse width modulation los tswj cov qib grey. LED tswj qhov system feem ntau muaj peb ntu: lub thawv tswj lub ntsiab, lub tshuab luam ntawv scanning thiab cov zaub thiab cov cuab yeej tswj.
Lub thawv tswj lub ntsiab tau txais cov ntaub ntawv ci ntsa iab ntawm txhua lub vijtsam pixel los ntawm lub khoos phis tawj tso saib daim npav, thiab tom qab ntawd xa rov qab mus rau ntau lub scanning boards, txhua lub scanning board yog lub luag haujlwm rau kev tswj ntau kab (kem) ntawm lub vijtsam LED, thiab txhua kab (kem) Cov zaub thiab tswj cov teeb liab ntawm lub sab sauv LED yog kis nyob rau hauv ib tug serial yam.
Tam sim no muaj ob txoj hauv kev los serially xa cov zaub tswj cov cim:
(1) Ib qho yog los tswj hwm qhov ntsuas grey ntawm txhua pixel ntawm lub rooj tsavxwm scanning. Lub scanning board decomposes tus nqi grey ntawm txhua kab ntawm pixels los ntawm lub thawv tswj (xws li mem tes dav modulation), thiab tom qab ntawd lub teeb liab tig ntawm txhua kab ntawm LEDs yog pulsed Daim ntawv (teeb li 1, tsis-lighted li {{ 4}}) yog serially kis mus rau cov coj LED raws li kab los tswj seb nws yog lit. Txoj kev no siv cov khoom siv tsawg dua, tab sis tus lej ntawm cov ntaub ntawv sib kis tau loj dua, vim tias nyob rau hauv lub voj voog rov qab teeb pom kev zoo, txhua pixel xav tau 16 pulses hauv 16- theem greyscale, thiab yuav tsum tau 256- theem greyscale. 256 pulses, vim qhov kev txwv ntawm cov cuab yeej ua haujlwm zaus, feem ntau lub vijtsam LED tsuas tuaj yeem ua tiav 16 qib grey.
(2) Ib qho yog pulse width modulation. Cov ntsiab lus ntawm serial kis tau tus mob ntawm lub scanning board tsis yog lub teeb liab hloov ntawm txhua LED tab sis ib tug 8- ntsis binary grey nqi. Txhua LED muaj nws tus kheej pulse dav modulator los tswj lub sijhawm teeb pom kev zoo. Nyob rau hauv txoj kev no, nyob rau hauv ib lub sij hawm ntawm rov qab teeb pom kev zoo, txhua pixel xav tau tsuas yog 4 pulses nyob rau hauv 16- theem greyscale thiab tsuas yog 8 pulses nyob rau hauv 256- theem greyscale, uas zoo heev txo cov serial kis zaus. Nrog rau txoj kev no ntawm dispersed tswj ntawm LED grey nplai, 256- theem grey scale tswj tau yooj yim paub.
