22.04.29Photo-response Non-uniformity (PRNU) yog ib qho kev sawv cev ntawm qhov sib xws ntawm lub koob yees duab cov lus teb rau lub teeb, tseem ceeb hauv qee qhov kev siv teeb pom kev zoo.
Thaum lub teeb pom los ntawm lub koob yees duab, tus naj npawb ntawm cov duab hluav taws xob ntes tau los ntawm txhua lub pixel thaum lub sijhawm raug ntsuas, thiab qhia rau lub computer raws li tus nqi greyscale (ADU). Qhov kev hloov pauv no los ntawm electrons rau ADUs ua raws li qee qhov piv txwv ntawm ADU ib lub tshuab hluav taws xob hu ua kev hloov pauv tau nce, ntxiv rau tus nqi them nyiaj ruaj khov (feem ntau 100 ADU). Cov nqi no yog txiav txim los ntawm Analogue-rau-digital converter thiab Amplifier siv rau kev hloov dua siab tshiab. CMOS cov koob yees duab tau txais lawv qhov ceev tsis txaus ntseeg thiab cov suab nrov tsawg los ntawm kev ua haujlwm sib luag, nrog ib lossis ntau dua analogue-rau-digital converters ib kab ntawm lub koob yees duab, thiab ib lub amplifier ib pixel. Qhov no txawm li cas los xij qhia txog lub sijhawm rau kev hloov pauv me me hauv kev nce thiab offset los ntawm pixel rau pixel.
Kev hloov pauv hauv tus nqi offset no tuaj yeem ua rau cov qauv suab nrov ntawm lub teeb qis, sawv cev los ntawm tusDSNU. PRNU sawv cev rau txhua qhov kev hloov pauv hauv qhov nce, qhov sib piv ntawm cov khoom siv hluav taws xob pom pom ADU. Nws sawv cev rau tus qauv sib txawv ntawm qhov nce qhov txiaj ntsig ntawm pixels. Muab hais tias qhov tshwm sim qhov sib txawv ntawm qhov kev siv qhov tseem ceeb yuav nyob ntawm qhov loj ntawm cov teeb liab, nws tau sawv cev raws li feem pua.
Yam PRNU qhov tseem ceeb yog <1%. Rau tag nrho cov duab qis- thiab nruab nrab-lub teeb, nrog cov teeb liab ntawm 1000e- lossis tsawg dua, qhov kev hloov pauv no yuav tsis tseem ceeb piv rau kev nyeem suab nrov thiab lwm yam suab nrov.
Tsis tas li ntawd thaum pom cov teeb pom kev siab, qhov sib txawv tsis zoo li qhov tseem ceeb piv rau lwm cov suab nrov hauv daim duab, xws li photon txhaj tshuaj suab nrov. Tab sis nyob rau hauv high-light imaging daim ntaub ntawv uas yuav tsum tau high-zoo ntsuas precision, tshwj xeeb tshaj yog cov uas siv ncej-nruab nrab los yog ncej-summing, tsawg PRNU tej zaum yuav pab tau.
