EMCCD Sensors: Lub teeb qis dua rau CCD |

Lub Electron-Multiplying CCD sensor yog qhov hloov pauv ntawm CCD sensor kom tso cai rau lub teeb qis dua. Lawv feem ntau yog npaj rau cov teeb liab ntawm ob peb puas photoelectrons, nqes mus rau tus kheej photon-suav qib.

Kab lus no piav qhia seb EMCCD sensors yog dab tsi, lawv ua haujlwm li cas, lawv qhov zoo thiab qhov tsis zoo, thiab vim li cas lawv thiaj li suav tias yog qhov kev hloov pauv tom ntej ntawm CCD thev naus laus zis rau cov duab qis.

Dab tsi yog EMCCD Sensor?

Ib qho Electron-Multiplying Charge-Coupled Device (EMCCD) sensor yog hom tshwj xeeb ntawm CCD sensor uas nthuav tawm cov cim tsis muaj zog ua ntej lawv nyeem tawm, tso cai rau kev nkag siab siab heev hauv qhov chaw qis qis.

Thaum xub thawj tsim rau cov ntawv thov xws li astronomy thiab microscopy siab heev, EMCCDs tuaj yeem ntes ib qho photons, ib txoj haujlwm uas ib txwm muaj CCD sensors tawm tsam nrog. Qhov kev muaj peev xwm los txheeb xyuas tus kheej photons ua rau EMCCDs tseem ceeb heev rau thaj chaw uas xav tau cov duab meej nyob rau hauv lub teeb qis heev.

EMCCD Sensors ua haujlwm li cas?

Txog rau qhov kev nyeem ntawv, EMCCD sensors ua haujlwm ntawm tib lub hauv paus ntsiab lus xws li CCD sensors. Txawm li cas los xij, ua ntej kev ntsuas nrog ADC, kuaj pom cov nqi raug muab sib npaug los ntawm cov txheej txheem hu ua impactionization, hauv 'electron multiplication register'. Tshaj li ntawm ntau pua kauj ruam, cov nqi los ntawm ib lub pixel yog txav mus raws li cov pixels masked ntawm high voltage. Txhua lub tshuab hluav taws xob ntawm txhua kauj ruam muaj txoj hauv kev los nqa cov electrons ntxiv. Yog li ntawd, lub teeb liab yog multiplied exponentially.

Qhov kawg tshwm sim ntawm qhov zoo-calibrated EMCCD yog lub peev xwm los xaiv tus nqi ntawm qhov nruab nrab qhov sib npaug, feem ntau nyob ib ncig ntawm 300 txog 400 rau kev ua haujlwm qis. Qhov no ua rau cov teeb liab pom tau tias yuav tsum tau sib npaug ntau dua li lub koob yees duab nyeem suab nrov, ua rau txo cov suab nrov ntawm lub koob yees duab nyeem. Hmoov tsis zoo, qhov xwm txheej ntawm cov txheej txheem sib tshooj no txhais tau hais tias txhua pixel yog sib npaug los ntawm qhov sib txawv, uas qhia txog lub suab nrov ntxiv, txo EMCCD lub teeb liab-rau-nruab nrab (SNR).

Ntawm no yog qhov kev tawg ntawm EMCCD sensors ua haujlwm li cas. Txog rau Kauj Ruam 6, cov txheej txheem ua tau zoo ib yam li ntawd rau CCD sensors.

Daim duab: Readout txheej txheem rau EMCCD sensor

Thaum kawg ntawm lawv qhov raug, EMCCD sensors ua ntej txav cov nqi xa mus rau lub npog ntsej muag ntawm pixels tib qhov ntev raws li lub teeb rhiab array (thav duab hloov chaw). Tom qab ntawd, ib kab ntawm ib lub sij hawm, cov nqi raug hloov mus rau hauv cov ntawv sau npe nyeem. Ib kem ntawm ib lub sij hawm, tsub nqi nyob rau hauv lub readout register yog kis mus rau ib tug multiplication register. Nyob rau txhua theem ntawm qhov kev sau npe no (txog 1000 theem hauv EMCCD lub koob yees duab tiag), txhua lub tshuab hluav taws xob muaj lub caij nyoog me me los tso tawm ib qho hluav taws xob ntxiv, sib faib cov teeb liab exponentially. Thaum kawg, cov teeb liab multiplied tau nyeem tawm.

1. Kev Them Nyiaj: Txhawm rau pib qhov tau txais, tus nqi yog ib txhij tshem tawm ntawm tag nrho cov sensor (lub ntiaj teb kaw).
2. Kev them nyiaj yug: Charges accumulates thaum raug.
3. Charge Cia: Tom qab kis tau, cov nqi sau tau raug hloov mus rau thaj chaw npog ntawm lub sensor, qhov chaw uas lawv tuaj yeem tos nyeem ntawv yam tsis muaj photons tshiab pom photons raug suav. Qhov no yog tus txheej txheem 'Frame Transfer'.
4. Next Frame Exposure: Nrog rau kev kuaj pom cov nqi khaws cia hauv lub ntsej muag pixels, cov pixels nquag tuaj yeem pib nthuav tawm ntawm tus ncej tom ntej (kev sib tshooj).
5. Txheej txheem nyeem ntawv: Ib kab ntawm ib lub sij hawm, tus nqi rau txhua kab ntawm cov ncej tiav raug hloov mus rau hauv 'Readout register'.
6. Ib kem ntawm ib lub sij hawm, tsub nqi ntawm txhua pixel yog shuttled mus rau lub readout node.
7. Electron Multiplication: Tom ntej no, tag nrho cov nqi hluav taws xob los ntawm pixel nkag mus rau hauv daim ntawv teev cov hluav taws xob sib npaug, thiab txav mus raws ib kauj ruam dhau los, muab ntau tus lej exponentially ntawm txhua kauj ruam.
8. Nyeem ntawv: Cov teeb liab sib npaug tau nyeem los ntawm ADC, thiab cov txheej txheem rov ua dua kom txog thaum tag nrho cov ncej tau nyeem tawm.

Pros thiab Cons ntawm EMCCD Sensors

Qhov zoo ntawm EMCCD Sensors

Qhov zoo	Kev piav qhia
Photon suav	Txheeb xyuas tus kheej photoelectrons nrog ultra-tsawg nyeem suab nrov (<0.2e⁻), ua rau ib leeg-photon rhiab heev.
Ultra-Low-Light Sensitivity	Qhov tseem ceeb zoo dua li cov CCDs ib txwm muaj, qee zaum dhau mus txawm tias high-end sCMOS koob yees duab ntawm cov teeb pom kev tsawg heev.
Tsawg Tsaus Tam Sim No	Kev sib sib zog nqus txias txo cov suab nrov thermal, ua kom cov duab huv si thaum lub sijhawm ntev.
'Half-Global' Shutter	Ncej hloov pauv tso cai rau ze-ntiaj teb raug nrog kev hloov pauv ceev heev (~ 1 microsecond).

● Photon suav: Nrog siab txaus electron sib npaug, nyeem cov suab nrov tuaj yeem raug tshem tawm (<0.2e-). Qhov no, nrog rau tus nqi nce siab thiab ze-zoo meej quantum efficiency, txhais tau hais tias qhov txawv ntawm ib tus neeg photoelectrons yog ua tau.
● Ultra-low-light rhiab heev: Piv rau CCDs, qhov kev ua haujlwm qis ntawm EMCCDs yog qhov zoo dua qub. Tej zaum yuav muaj qee cov ntawv thov uas EMCCD muab kev tshawb pom zoo dua thiab qhov sib txawv txawm tias qhov siab tshaj sCMOS ntawm qhov qis tshaj qhov pom tau.
● Tsawg Tsaus Tam Sim No: Raws li nrog CCDs, EMCCDs feem ntau yog sib sib zog nqus txias thiab muaj peev xwm xa cov nqi qis heev tam sim no.
● 'Ib nrab Ntiaj Teb' Shutter: Cov txheej txheem hloov mus rau qhov pib thiab xaus tsis yog tib lub sijhawm, tab sis feem ntau yuav siv sij hawm ntawm 1 microsecond.

Cons ntawm EMCCD Sensors

Qhov tsis zoo	Kev piav qhia
Txwv ceev	Qhov siab tshaj plaws tus nqi (~ 30 fps ntawm 1 MP) yog qeeb qeeb dua li niaj hnub CMOS lwm txoj hauv kev.
Amplification suab nrov	Qhov xwm txheej tsis sib xws ntawm cov khoom siv hluav taws xob nthuav qhia ntau lub suab nrov, txo SNR.
Clock-Induced Charge (CIC)	Kev txav ceev ceev tuaj yeem qhia cov cim tsis tseeb uas tau txais kev nthuav dav.
Txo Dynamic Range	Kev nce siab txo qhov siab tshaj plaws lub teeb liab lub sensor tuaj yeem ua haujlwm ua ntej saturating.
Loj Pixel Loj	Qhov ntau thiab tsawg pixels (13-16 μm) yuav tsis ua raws li ntau qhov kev xav tau ntawm qhov kho qhov muag.
Heavy Cooling Requirement	Kev sib sib zog nqus cua txias yuav tsum tau ua kom tau raws li qhov sib npaug thiab tsis muaj suab nrov.
Calibration Xav Tau	EM nce degrades raws sij hawm (multiplication decay), yuav tsum tau calibration tsis tu ncua.
Short Exposure Instability	Kev nthuav tawm luv luv tuaj yeem ua rau lub teeb liab tsis muaj zog thiab suab nrov.
Tus nqi siab	Complex manufacturing thiab sib sib zog nqus txias ua rau cov sensors kim dua sCMOS.
Txwv Lifespan	Cov ntawv sau npe electron sib npaug hnav tawm, feem ntau kav ntev li 5-10 xyoo.
Export Cov Kev Sib Tw	Ua raws li cov kev cai nruj vim muaj peev xwm siv tub rog.

● Txwv ceev: Fast EMCCDs muab ib ncig ntawm 30 fps ntawm 1 MP, zoo ib yam li CCDs, kev txiav txim siab qeeb dua li CMOS koob yees duab.

● Suab Taw Qhia: Qhov 'cov suab nrov tshaj' tshwm sim los ntawm qhov sib npaug ntawm cov hluav taws xob sib txuas, piv rau lub koob yees duab qis sCMOS nrog tib lub quantum efficiency, tuaj yeem muab EMCCDs suab nrov ntau dua nyob ntawm theem teeb liab. SNR rau high-end sCMOS feem ntau zoo dua rau cov teeb liab ntawm ib puag ncig 3e-, txawm tias ntau dua rau cov teeb liab siab dua.

● Clock-Induced Charge (CIC): Tshwj tsis yog tswj kom zoo, kev txav ntawm cov nqi thoob plaws lub sensor tuaj yeem qhia cov khoom siv hluav taws xob ntxiv rau hauv pixels. Cov suab nrov no ces muab sib npaug los ntawm cov npe ntawm electron multiplication register. Cov nqi zog siab dua (cov nqi moos) ua rau cov ncej siab dua, tab sis ntau CIC.

● Txo Dynamic Range: Cov nqi hluav taws xob ntau heev uas yuav tsum tau kov yeej EMCCD nyeem cov suab nrov ua rau txo qis ntau yam.

● Loj Pixel Loj: Qhov tsawg tshaj plaws pixel loj rau EMCCD cov koob yees duab yog 10 μm, tab sis 13 lossis 16 μm feem ntau. Qhov no yog qhov loj heev kom haum rau feem ntau cov tshuab kho qhov muag 'kev daws teeb meem.

● Calibration Requirements: Cov txheej txheem hluav taws xob sib npaug hnav tawm ntawm EM sau npe nrog kev siv, txo nws lub peev xwm los sib faib hauv cov txheej txheem hu ua 'electron multiplication decay'. Qhov no txhais tau hais tias qhov nce ntawm lub koob yees duab hloov tas li, thiab lub koob yees duab yuav tsum tau calibration tsis tu ncua los ua ib qho kev ntsuas ntau.

● Kev tsis sib haum xeeb ntawm Lub Sijhawm luv: Thaum siv lub sijhawm luv luv, EMCCD cov koob yees duab tuaj yeem tsim cov txiaj ntsig tsis sib xws vim tias lub teeb liab tsis muaj zog tau dhau los ntawm lub suab nrov, thiab cov txheej txheem nthuav dav qhia txog kev hloov pauv ntawm cov lej.

● Heavy Cooling Requirement: Cov txheej txheem electron multiplication muaj zog cuam tshuam los ntawm qhov kub thiab txias. Txias lub sensor nce qhov muaj hluav taws xob ntau ntxiv. Yog li kev sib sib zog nqus sensor txias thaum tswj qhov kub thiab txias yog qhov tseem ceeb rau kev ntsuas EMCCD.

● Tus nqi siab: Qhov nyuaj ntawm kev tsim khoom ntawm cov khoom siv ntau yam no, ua ke nrog kev sib sib zog nqus txias, ua rau cov nqi feem ntau siab tshaj qhov zoo tshaj plaws sCMOS sensor koob yees duab.

● Txwv Lifespan: Electron multiplication decay tso ib qho kev txwv rau lub neej ntawm cov sensors kim kim ntawm feem ntau 5-10 xyoo, nyob ntawm qib ntawm kev siv.

● Export Kev Sib Tw: Kev ntshuam thiab xa tawm ntawm EMCCD sensors nyhav rau logistically nyuaj vim lawv muaj peev xwm siv tau rau hauv kev siv tub rog.

Yog vim li cas EMCCD yog tus Successor rau CCD

Feature	CCD	EMCCD
rhiab heev	Siab	Ultra-siab (tshwj xeeb tshaj yog lub teeb qis)
Readout Noise	Nruab nrab	Tsawg heev (vim nce)
Dynamic Range	Siab	Nruab nrab (tsuas yog nce)
Nqi	qis	Siab dua
Txias	xaiv tau	Feem ntau xav tau rau kev ua haujlwm zoo
Siv Cases	General duab	Tsawg-teeb, ib leeg-photon nrhiav kom tau

EMCCD sensors tsim los ntawm CCD thev naus laus zis ib txwm siv los ntawm kev sib koom ua ke ntawm cov kauj ruam hluav taws xob. Qhov no txhim kho lub peev xwm los nthuav tawm cov cim tsis muaj zog thiab txo cov suab nrov, ua rau EMCCDs yog qhov kev xaiv zoo tshaj plaws rau daim ntawv thov kev siv lub teeb pom kev tsawg heev uas CCD sensors poob luv.

Kev siv tseem ceeb ntawm EMCCD Sensors

EMCCD sensors feem ntau yog siv rau hauv kev tshawb fawb thiab kev lag luam uas xav tau siab rhiab heev thiab muaj peev xwm txheeb xyuas cov teeb liab faint:

● Kev Tshawb Fawb Txog Kev Ua Neejg: Rau cov ntawv thov xws li ib leeg-molecule fluorescence microscopy thiab tag nrho cov sab hauv kev xav fluorescence (TIRF) microscopy.
● Astronomy: Siv rau kev ntes lub teeb pom kev los ntawm cov hnub qub nyob deb, galaxies, thiab kev tshawb fawb exoplanet.
● Quantum Optics: Rau photon entanglement thiab quantum ntaub ntawv thwmsim.

● Forensics thiab Security: Ua hauj lwm hauv kev soj ntsuam lub teeb qis thiab tshawb xyuas cov ntaub ntawv pov thawj.
● Spectroscopy: Nyob rau hauv Raman spectroscopy thiab low-intensity fluorescence detection.

Thaum twg Koj Yuav Tsum Xaiv EMCCD Sensor?

Nrog rau kev txhim kho rau CMOS sensors nyob rau xyoo tas los no, kev nyeem suab nrov ntawm EMCCD sensors tau ploj zuj zus vim tam sim no txawm tias sCMOS koob yees duab muaj peev xwm ntawm subelectron nyeem suab nrov, nrog rau ntau yam ntawm lwm cov txiaj ntsig. Yog tias ib daim ntawv thov tau siv EMCCDs yav dhau los, nws yog qhov tsim nyog los tshuaj xyuas seb qhov no yog qhov kev xaiv zoo tshaj plaws rau kev txhim kho hauv sCMOS.

Keeb kwm, EMCCDs tseem tuaj yeem ua tiav photon suav ntau dua, nrog rau ob peb lwm cov ntawv thov niche nrog cov teeb liab raug qis dua 3-5e- ib pixel ntawm lub ncov. Txawm li cas los xij, nrog qhov loj ntawm pixels thiab sub-electron nyeem suab nrov ua muaj nyob rau hauvkoob yees duab scientificraws li sCMOS thev naus laus zis, nws muaj peev xwm cov ntawv thov no kuj yuav sai sai no nrog high-end sCMOS.

FAQs

Dab tsi yog Lub Sijhawm Tshaj Tawm Tsawg kawg rau Ncej Hloov Lub Koob Yees Duab?

Rau txhua tus ncej hloov pauv hloov pauv, suav nrog EMCCDs, cov lus nug ntawm qhov tsawg kawg nkaus tuaj yeem raug lub sijhawm yog qhov nyuaj. Rau ib qho kev tau txais cov duab, qhov raug tuaj yeem xaus tau los ntawm kev sib tsoo cov nqi nkag mus rau hauv cheeb tsam npog kom nyeem tau sai heev, thiab luv luv (sub-microsecond) lub sij hawm raug tsawg kawg nkaus tau.

Txawm li cas los xij, sai li sai tau thaum lub koob yees duab streaming ntawm qhov nrawm nrawm, ieacquiring ntau thav duab / ib zaj yeeb yaj kiab ntawm tus ncej tag nrho, sai li sai tau thaum thawj daim duab tiav nthuav tawm, thaj chaw npog npog tau nyob ntawm tus ncej kom txog thaum nyeem ntawv tiav. Yog li ntawd, qhov tshwm sim tsis tuaj yeem xaus. Qhov no txhais tau hais tias, tsis hais txog lub sijhawm raug thov hauv software, lub sijhawm raug cuam tshuam tiag tiag ntawm cov thav ntawv tom ntej tom qab thawj zaug ntawm kev sib tw ntau-nruab nrawm yog muab los ntawm lub sijhawm thav duab, piv txwv li 1 / Ncej Rate, ntawm lub koob yees duab.

Puas yog sCMOS Technology Hloov EMCCD Sensors?

EMCCD cov koob yees duab muaj ob qhov tshwj xeeb uas pab khaws lawv cov txiaj ntsig hauv qhov xwm txheej tsis tshua muaj teeb pom kev zoo (nrog cov teeb liab siab tshaj ntawm 5 photoelectrons lossis tsawg dua). Ua ntej, lawv cov pixels loj, mus txog 16 μm, thiab thib ob lawv <1e- nyeem suab nrov.

Ib tiam tshiab ntawmsCMOS koob yees duabtau tshwm sim uas muaj cov yam ntxwv zoo ib yam, tsis muaj ntau qhov tsis zoo ntawm EMCCDs, tshwj xeeb tshaj yog cov suab nrov tshaj. Cov koob yees duab xws li Aries 16 los ntawm Tucsen muab 16 μm rov qab-illuminated pixels nrog lub suab nrov ntawm 0.8e-. Nrog lub suab qis thiab 'natively' loj pixels, cov koob yees duab no kuj ua tau zoo tshaj plaws binned sCMOS koob yees duab, vim muaj kev sib raug zoo ntawm binning thiab nyeem suab nrov.

Yog tias koj xav paub ntau ntxiv txog EMCCD, thov nyem:

EMCCD puas tuaj yeem hloov pauv thiab peb puas xav tau qhov ntawd?