I-MTF (i-Modulation Transfer Function) ijika yegrafu isebenza njengesixhobo sohlalutyo esibalulekileyo sokuvavanya ukusebenza kwe-optical ye-lens. Ngokulinganisa amandla e-lens okugcina umahluko kuwo wonke amaza ohlukeneyo esithuba, ibonisa ngokubonakalayo iimpawu eziphambili zokucinga ezifana nesisombululo, ukunyaniseka kokuthelekisa, kunye nokungaguquguquki komphetho. Apha ngezantsi kukho inkcazo eneenkcukacha:
I. Ukutolikwa kwee-Axes zoNxibelelwano kunye neeCurves
Umgca oxwesileyo (umgama ukusuka kumbindi)
Le axis imele umgama ukusuka kumbindi womfanekiso (ukuqala kwi-0 mm ngakwesobunxele) ukuya emphethweni (indawo yokuphela ngasekunene), ilinganiswe ngeemilimitha (mm). Kwiilensi ezipheleleyo, ingqalelo ekhethekileyo kufuneka ihlawulwe kuluhlu ukusuka kwi-0 ukuya kwi-21 mm, ehambelana nesiqingatha se-diagonal ye-sensor (43 mm). Kwiilensi zefomati ye-APS-C, uluhlu olufanelekileyo lukhawulelwe kwi-0 ukuya kwi-13 mm, emele inxalenye ephakathi yesangqa somfanekiso.
Umgca othe nkqo (Ixabiso leMTF)
I-axis ethe nkqo ibonisa iqondo apho ilensi igcina umahluko, ukusuka ku-0 (akukho mahluko ugciniweyo) ukuya ku-1 (ugcino olugqibeleleyo lomahluko). Ixabiso le-1 limele imeko efanelekileyo yethiyori engenakufezekiswa ekusebenzeni, ngelixa ixabiso elisondeleyo kwi-1 libonisa ukusebenza okuphezulu.
Iintlobo zeCwave eziPhambili
Ukuphindaphindwa koMhlaba (Iyunithi: izibini zomgca ngemilimitha nganye, lp/mm):
- Ijiko le-10 lp/mm (elimelwe ngumgca oshinyeneyo) libonisa isakhono sokuzala ngokuchasayo kwelensi. Ixabiso le-MTF elingaphezulu kwe-0.8 lithathwa ngokuba ligqwesile.
- I-30 lp / mm ijika (emelwe ngumgca omncinci) ibonisa amandla okusombulula lens kunye nobukhali. Ixabiso le-MTF elingaphezu kwe-0.6 lithathwa njengelilungile.
Umkhomba-ndlela womgca:
- Umgca oSolid (I-S / Sagittal okanye iRadial): Imele imigca yovavanyo enwebeka ngaphandle ukusuka embindini (umz., ufana nezipoki kwivili).
– Umgca onamachaphaza (M / Meridional okanye Tangential): Imele imigca yovavanyo ecwangciswe ngokwezangqa ezigxininisiweyo (umz., iipateni ezinjengeringi).
II. Iinqobo zoVavanyo lweNtsebenzo
Ukuphakama kweCwave
Ummandla oseMbindini (Icala lasekhohlo le-Horizontal Axis): Amaxabiso e-MTF aphezulu kuzo zombini i-10 lp/mm kunye ne-30 lp/mm iigophe zibonisa umfanekiso obukhali osembindini. Iilensi eziphezulu zihlala zifikelela amaxabiso aphakathi kwe-MTF ngaphezulu kwe-0.9.
Ummandla we-Edge (Icala lasekunene le-Horizontal Axis): Ukuthotywa okusezantsi kwamaxabiso e-MTF ngakwimida kubonisa ukusebenza kakuhle komphetho. Ngokomzekelo, i-edge ye-MTF yexabiso le-30 lp / mm enkulu kune-0.4 iyamkeleka, ngelixa ukugqithisa kwe-0.6 kuthathwa njengegqwesileyo.
Igophe eligudileyo
Inguqu egudileyo phakathi kombindi kunye nomphetho icebisa ukusebenza komfanekiso ongaguqukiyo kwisakhelo. Ukuhla okunyukayo kubonisa ukuhla okubalulekileyo komgangatho womfanekiso ukuya emaphethelweni.
Ukusondela kwe-S kunye ne-M Curves
Ukusondela kwe-sagittal (umgca oqinileyo) kunye ne-meridional (i-dashed line) iigophe zibonisa ulawulo lwe-astigmatism ye-lens. Ulungelelwaniso olusondeleyo lukhokelela kwi-bokeh yendalo engaphezulu kunye nokunciphisa ukuphambuka. Ukwahlula okubalulekileyo kunokukhokelela kwimiba enjengokujolisa ukuphefumla okanye ubugcisa bemigca emibini.
III. Izinto ezongezelelweyo ezinempembelelo
Ubungakanani boMvula
Ubuninzi beAperture (umzekelo, f/1.4): Inganika i-MTF ephezulu esembindini kodwa inokubangela ukuthotywa komphetho ngenxa yokuphambuka kwamehlo.
Esona sithuba sivulelekileyo (umzekelo, f/8): Ngokuqhelekileyo sinika ukusebenza kwe-MTF elungeleleneyo kwisakhelo kwaye isoloko iphawulwa ngeblue kwiigrafu ze-MTF.
Ukwahluka kweLens yoSondeza
Kwiilensi zokusondeza, iigophe ze-MTF kufuneka zivavanywe ngokwahlukeneyo kwi-engile-ebanzi kunye nesiphelo se-telephoto, njengoko ukusebenza kunokwahluka ngobude bojoliso.
IV. Iingqwalasela ezibalulekileyo
Imida yoHlahlelo lwe-MTF
Ngelixa i-MTF ibonelela ngezimvo ezixabisekileyo kwisisombululo nakuchasaniso, ayibandakanyi ezinye iziphene zamehlo ezinje ngokugqwetheka, ukuphambuka kwechromatic, okanye ukudangala. Le miba ifuna uvandlakanyo olongezelelweyo kusetyenziswa iimetrikhi ezongezelelweyo.
Uthelekiso lweCross-Brand
Ngenxa yeeyantlukwano kwiindlela zokuvavanya kunye nemigangatho phakathi kwabavelisi, uthelekiso oluthe ngqo lweegophe ze-MTF kwiimpawu ezahlukeneyo kufuneka luthintelwe.
I-Curve Stability kunye ne-Symmetry
Ukuguquguquka okungaqhelekanga okanye i-asymmetry kwii-curves ze-MTF zingabonisa ukungahambi kakuhle kokuvelisa okanye imiba yokulawula umgangatho.
Isishwankathelo esiKhawulezayo:
Iimpawu zeeLensi eziSebenza ngokuPhezulu:
– Igophe elipheleleyo le-10 lp/mm lihlala lingaphezulu kwe-0.8
– Central 30 lp/mm idlula 0.6
-Edge 30 lp/mm idlula i-0.4
-I-Sagittal kunye ne-meridional curves zihambelana ngokusondeleyo
-I-MTF egudileyo kunye nokubola ngokuthe ngcembe ukusuka embindini ukuya emphethweni
Ugqaliselo loVavanyo oluPhambili:
– Central 30 lp/mm ixabiso
-Inqanaba lokuthotywa kwe-MTF
-Umda weegophe ze-S kunye ne-M
Ukugcina ukugqwesa kuzo zontathu iinkalo kubonisa ngokucacileyo uyilo oluphezulu lwe-optical kunye nomgangatho wokwakha.
Ixesha lokuposa: Jul-09-2025