25/08/01Firikwensin CCD na Electron-Multiplying shine juyin halitta na firikwensin CCD don ba da damar aikin ƙananan haske. Yawanci an yi nufin su don sigina na ƴan ɗaruruwan photoelectrons, har zuwa matakin ƙidaya na photon.
Wannan labarin ya bayyana abin da na'urori masu auna firikwensin EMCCD, yadda suke aiki, fa'idodin su da rashin amfanin su, da kuma dalilin da yasa ake ɗaukar su juyin halitta na gaba na fasahar CCD don ƙananan haske.
Menene Sensor EMCCD?
Na'urar Haɗa Haɗaɗɗen Caji (EMCCD) firikwensin nau'in firikwensin CCD ne na musamman wanda ke haɓaka sigina mara ƙarfi kafin a karanta su, yana ba da damar haɓakar hankali sosai a cikin ƙaramin haske.
Da farko an ƙirƙira don aikace-aikace irin su ilmin taurari da ci-gaba microscopy, EMCCDs na iya gano photon guda ɗaya, aikin da na'urorin CCD na gargajiya ke fama da shi. Wannan ikon gano hoto na mutum ɗaya yana sa EMCCDs mahimmanci ga filayen da ke buƙatar ainihin hoto a ƙarƙashin ƙananan matakan haske.
Ta yaya EMCCD Sensors Aiki?
Har zuwa lokacin karantawa, na'urori masu auna firikwensin EMCCD suna aiki akan ka'idoji iri ɗaya da na'urori masu auna firikwensin CCD. Koyaya, kafin aunawa tare da ADC, ana haɓaka cajin da aka gano ta hanyar tsari da ake kira tasiri, a cikin 'rejista multiplication'. Fiye da jerin matakai ɗari da yawa, ana motsa cajin daga pixel tare da jerin pixels masu rufe fuska a babban ƙarfin lantarki. Kowane electron a kowane mataki yana da damar kawo ƙarin electrons. Don haka ana ninka siginar da yawa.
Sakamakon ƙarshe na EMCCD mai ƙima shine ikon zaɓar madaidaicin adadin matsakaita ninka, yawanci a kusa da 300 zuwa 400 don ƙaramin haske. Wannan yana ba da damar siginar da aka gano don ninka su sama da hayaniyar karatun kamara, a sakamakon haka yana rage ƙarar karatun kamara. Abin baƙin cikin shine, yanayin stochastic na wannan tsarin ninkawa yana nufin kowane pixel ana ninka shi da wani adadi daban-daban, wanda ke gabatar da ƙarin amo, yana rage ƙimar siginar-zuwa-amo na EMCCD (SNR).
Anan ga rugujewar yadda na'urori masu auna firikwensin EMCCD ke aiki. Har zuwa Mataki na 6, tsarin yana daidai da na na'urorin CCD.
Hoto: Tsarin karantawa don firikwensin EMCCD
A ƙarshen bayyanar su, na'urori masu auna firikwensin EMCCD da sauri suna matsar da cajin da aka tattara zuwa ɗimbin ƙira na pixels daidai da ma'aunin haske (canja wurin firam). Sannan, layi ɗaya a lokaci guda, ana matsar da caji cikin rajistar karantawa. Shafi ɗaya a lokaci ɗaya, ana wuce cajin da ke cikin rajistar karantawa zuwa rijistar ninkawa. A kowane mataki na wannan rajista (har zuwa matakai 1000 a cikin kyamarori na EMCCD na ainihi), kowane lantarki yana da ƙaramin damar sakin ƙarin lantarki, yana ninka siginar da yawa. A ƙarshe, ana karanta siginar da aka ninka.
1. Sharer Caji: Don fara sayan, ana cire cajin lokaci guda daga dukkan firikwensin (shutter na duniya).
2. Tarin CajiCaji yana taruwa yayin fallasa.
3. Ajiye Caji: Bayan fallasa, ana matsar da cajin da aka tattara zuwa wurin da abin rufe fuska na firikwensin, inda za su iya jiran karantawa ba tare da an kirga sabbin hotunan photon ba. Wannan shine tsarin 'Frame Transfer'.
4. Bayyanar Frame na gaba: Tare da cajin da aka gano da aka adana a cikin pixels masu rufe fuska, pixels masu aiki zasu iya fara bayyanar firam na gaba (yanayin zoba).
5. Tsarin Karatu: Jeri ɗaya a lokaci ɗaya, ana matsar da cajin kowane layi na firam ɗin da aka gama zuwa cikin 'rejistar karantawa'.
6. Shafi ɗaya a lokaci guda, caji daga kowane pixel ana rufe shi zuwa kumburin karantawa.
7. Yawaita Electron: Bayan haka, duk cajin lantarki daga pixel ɗin suna shigar da rajistar multiplication na lantarki, kuma suyi tafiya tare da mataki-mataki, suna ninka lamba da yawa a kowane mataki.
8. Karantawa: Ana karanta siginar da aka ninka ta ADC, kuma ana maimaita tsarin har sai an karanta firam gabaɗaya.
Ribobi da Fursunoni na EMCCD Sensors
Ribobi na EMCCD Sensors
| Amfani | Bayani |
| Ƙididdigar Photon | Yana gano nau'ikan photoelectrons guda ɗaya tare da ƙaramar ƙaranci mai ƙaranci (<0.2e⁻), yana ba da damar jin daɗin hoto ɗaya. |
| Matsanancin-Ƙarancin-haske | Mahimmanci mafi kyau fiye da CCD na gargajiya, wani lokacin ma sun zarce ko da manyan kyamarori na sCMOS a ƙananan matakan haske. |
| Karancin Dark Yanzu | Zurfafa sanyaya yana rage amo mai zafi, yana ba da damar tsaftataccen hotuna yayin dogon fallasa. |
| 'Half-Global' Shutter | Canja wurin firam ɗin yana ba da damar kusan-duniya fidda kai tare da canjin caji mai sauri (~ 1 microsecond). |
● Ƙididdigar Photon: Tare da babban isassun wutar lantarki, ana iya kawar da amo a zahiri (<0.2e-). Wannan, tare da ƙimar riba mai girma da daidaitaccen ƙimar ƙididdigewa, yana nufin cewa bambance kowane photoelectrons yana yiwuwa.
● Ƙarƙashin Ƙarƙashin Ƙarfafa Haske: Idan aka kwatanta da CCDs, ƙarancin haske na EMCCDs ya fi kyau sosai. Wataƙila akwai wasu aikace-aikacen da EMCCD ke ba da mafi kyawun iya ganowa da bambanci har ma fiye da sCMOS masu tsayi a mafi ƙarancin matakan haske.
● Karancin Dark Yanzu: Kamar yadda yake tare da CCDs, EMCCDs yawanci suna da sanyi sosai kuma suna iya sadar da ƙananan ƙimar halin yanzu duhu.
● Rufe 'Rabin Duniya': Tsarin canja wurin firam don farawa da ƙarshen bayyanarwa ba gaskiya ba ne a lokaci ɗaya, amma yawanci yana ɗaukar tsari na 1 microsecond.
Fursunoni na EMCCD Sensors
| Hasara | Bayani |
| Gudun iyaka | Matsakaicin ƙimar firam (~ 30 fps a 1 MP) sun fi hankali fiye da na zamani na CMOS. |
| Ƙara Hayaniyar | Halin bazuwar haɓakar lantarki yana gabatar da hayaniyar wuce gona da iri, yana rage SNR. |
| Cajin Agogo (CIC) | Motsin caji mai sauri na iya gabatar da siginonin ƙarya waɗanda ke haɓakawa. |
| Rage Rage Rage Rage Tsayi | Babban riba yana rage iyakar sigina da firikwensin zai iya ɗauka kafin daidaitawa. |
| Girman Girman Pixel | Girman pixel gama-gari (13-16 μm) ƙila ba za su daidaita da yawancin buƙatun tsarin gani ba. |
| Bukatun sanyaya mai nauyi | Ana buƙatar kwanciyar hankali mai zurfi mai zurfi don cimma daidaiton haɓakawa da ƙaramar amo. |
| Bukatun daidaitawa | Samun EM yana raguwa akan lokaci (lalacewar ninka), yana buƙatar daidaitawa na yau da kullun. |
| Rashin Kwanciyar Hankali | Takaitaccen bayani na iya haifar da ƙarar sigina da hayaniya mara misaltuwa. |
| Babban farashi | Ƙirƙirar masana'anta da zurfin sanyaya suna sanya waɗannan na'urori masu auna firikwensin tsada fiye da sCMOS. |
| Tsawon rayuwa mai iyaka | Rijistar multiplication na lantarki ya ƙare, yawanci yana ɗaukar shekaru 5-10. |
| Kalubalen fitarwa | Dangane da tsauraran ƙa'idodi saboda yuwuwar aikace-aikacen soja. |
● Gudun iyaka: EMCCDs masu sauri suna ba da kusan fps 30 a 1 MP, kama da CCDs, umarni masu girma a hankali fiye da kyamarori CMOS.
● Gabatarwar surutu: The 'excess amo factor' lalacewa ta hanyar bazuwar electron multiplication, idan aka kwatanta da ƙaramar amo sCMOS kamara tare da wannan adadi iya aiki, na iya ba EMCCDs matuƙar girma amo dangane da sigina matakan. SNR na sCMOS mai tsayi ya fi kyau don sigina na kusa da 3e-, har ma fiye da sigina mafi girma.
● Cajin Agogo (CIC): Sai dai idan an sarrafa shi a hankali, motsi na caji a cikin firikwensin zai iya shigar da ƙarin electrons zuwa pixels. Ana kuma ninka wannan ƙara ta hanyar rajistar multiplication na lantarki. Matsakaicin saurin motsi (yawan agogo) yana haifar da ƙimar firam mafi girma, amma ƙarin CIC.
● Rage Rage Rage Rage Rage: Maɗaukakin maɗaukakin lantarki da ake buƙata don shawo kan ƙarar EMCCD yana haifar da raguwa mai yawa.
● Girman Girman Pixel: Mafi ƙarancin girman pixel gama-gari don kyamarori EMCCD shine 10 μm, amma 13 ko 16 μm ya fi kowa. Wannan yayi girma da yawa don dacewa da mafi yawan buƙatun ƙudurin tsarin gani.
● Bukatun daidaitawa: Tsarin multiplication na lantarki yana lalata rajistar EM tare da amfani, yana rage ikonsa na ninkawa a cikin tsarin da ake kira 'electron multiplication decay'. Wannan yana nufin ribar kamara tana canzawa koyaushe, kuma kyamarar tana buƙatar daidaitawa akai-akai don yin kowane hoto mai ƙima.
● Bayyanar da ba daidai ba a Ƙananan Lokaci: Lokacin amfani da ɗan gajeren lokutan fallasa, kyamarorin EMCCD na iya haifar da sakamako marasa daidaituwa saboda siginar rauni yana mamaye shi da hayaniya, kuma tsarin haɓakawa yana gabatar da juzu'i na ƙididdiga.
● Bukatar sanyaya mai nauyi: Tsarin dumbin lantarki yana tasiri sosai da zafin jiki. Sanyaya firikwensin yana ƙara yawan haɓakar wutar lantarki. Don haka sanyaya firikwensin zurfin firikwensin yayin kiyaye kwanciyar hankali don haka yana da mahimmanci ga sake fasalin ma'aunin EMCCD.
● Babban farashi: Wahalar kera waɗannan na'urori masu auna firikwensin, haɗe tare da sanyaya mai zurfi, yana haifar da farashin yawanci sama da mafi ingancin kyamarori na firikwensin sCMOS.
● Iyakar Rayuwa: Lalacewar haɓakar wutar lantarki yana sanya iyaka akan rayuwar waɗannan na'urori masu tsada na yawanci shekaru 5-10, ya danganta da matakin amfani.
● Kalubalen fitarwa: Shigo da fitarwa na na'urori masu auna firikwensin EMCCD yana nuna ƙalubale na dabaru saboda yuwuwar amfani da su a aikace-aikacen soja.
Me yasa EMCCD shine Magajin CCD
| Siffar | CCD | Farashin EMCCD |
| Hankali | Babban | Ultra-high (musamman ƙananan haske) |
| Kara karantawa | Matsakaici | Matsakaicin ƙasa (saboda riba) |
| Rage Rage | Babban | Matsakaici (iyakance ta hanyar riba) |
| Farashin | Kasa | Mafi girma |
| Sanyi | Na zaɓi | Yawanci ana buƙata don ingantaccen aiki |
| Amfani da Cases | Gabaɗaya hoto | Ƙananan haske, gano hoto ɗaya |
Na'urori masu auna firikwensin EMCCD suna ginawa akan fasahar CCD ta gargajiya ta hanyar haɗa matakin haɓaka na lantarki. Wannan yana haɓaka ikon haɓaka sigina masu rauni da rage hayaniya, sa EMCCDs ya zama zaɓin da aka fi so don aikace-aikacen hoto mai ƙarancin haske inda firikwensin CCD suka gaza.
Maɓallin Aikace-aikace na EMCCD Sensors
Ana amfani da na'urori masu auna firikwensin EMCCD a fannonin kimiyya da masana'antu waɗanda ke buƙatar babban hankali da ikon gano sigina masu rauni:
● Hasashen Kimiyyar Rayuwag: Don aikace-aikace kamar microscopy mai kyalli guda ɗaya da jimillar haske mai haske na ciki (TIRF).
● Ilimin taurariAn yi amfani da shi don ɗaukar haske mara ƙarfi daga taurari masu nisa, taurari, da binciken exoplanet.
● Ƙwayoyin gani na Quantum: Don haɗin gwiwar photon da gwaje-gwajen bayanan ƙididdiga.
● Likitoci da Tsaro: An yi aiki a cikin ƙananan haske da bincike na shaida.
● Spectroscopy: A cikin Raman spectroscopy da gano ƙananan haske mai ƙarfi.
Yaushe Ya Kamata Ka Zaba Sensor EMCCD?
Tare da haɓakawa ga na'urori masu auna firikwensin CMOS a cikin 'yan shekarun nan, ƙimar ƙarar amo na na'urori masu auna firikwensin EMCCD ya ragu kamar yadda yanzu har ma da kyamarori na sCMOS suna da ikon karanta amo na subelectron, tare da fa'idodi masu yawa. Idan aikace-aikacen ya yi amfani da EMCCD a baya, yana da kyau a duba ko wannan shine mafi kyawun zaɓi da aka bayar a cikin sCMOS.
A tarihi, EMCCDs na iya yin ƙidayar photon cikin nasara, tare da wasu ƴan aikace-aikacen niche waɗanda ke da matakan sigina na yau da kullun ƙasa da 3-5e- kowane pixel a kololuwa. Ko da yake, tare da girman pixels masu girma da ƙarar ƙararrakin lantarki suna samun samuwa a cikikyamarori na kimiyyadangane da fasahar sCMOS, yana yiwuwa waɗannan aikace-aikacen suma nan ba da jimawa ba za a iya yin su tare da babban sCMOS.
FAQs
Menene Mafi ƙarancin Lokacin Bayyanawa don Canja wurin kyamarori?
Ga duk na'urorin canja wurin firam, gami da EMCCDs, tambayar mafi ƙarancin lokacin bayyanawa mai rikitarwa ce. Don siyan hoto ɗaya, za'a iya ƙare fiddawar ta hanyar jujjuya cajin da aka samu zuwa yankin da aka rufe da rufe fuska don karantawa cikin sauri, kuma gajeriyar (ƙarancin na biyu) mafi ƙarancin lokuta yana yiwuwa.
Koyaya, da zaran kyamarar tana yawo cikin cikakken sauri, watau samun firam da yawa / fim a cikakken ƙimar firam, da zaran hoton farko ya gama fallasa, yankin da aka rufe yana mamaye wannan firam ɗin har sai an gama karantawa. Sakamakon ba zai iya ƙarewa ba. Wannan yana nufin cewa, ba tare da la'akari da lokacin fallasa da ake buƙata a cikin software ba, ainihin lokacin bayyanar firam na gaba bayan farkon farkon sayan firam ɗin da yawa yana ba da lokacin firam, watau 1 / Frame Rate, na kamara.
Shin Fasahar sCMOS tana Maye gurbin EMCCD Sensors?
Kyamarorin EMCCD suna da ƙayyadaddun bayanai guda biyu waɗanda suka taimaka riƙe fa'idarsu a cikin yanayin hoto mai ƙarancin haske (tare da matakan sigina na 5 photoelectrons ko ƙasa da haka). Na farko, manyan pixels ɗin su, har zuwa 16 μm, na biyu kuma <1e- ƙarar su.
Wani sabon ƙarni nasCMOS kamaraya fito wanda ke ba da waɗannan halaye iri ɗaya, ba tare da ɗimbin kurakuran EMCCDs ba, musamman ma ƙarar amo. Kyamara irin su Aries 16 daga Tucsen suna ba da pixels masu haske na baya μm 16 tare da ƙarar ƙarar 0.8e-. Tare da ƙananan amo da manyan pixels 'na asali', waɗannan kyamarori kuma sun zarce mafi yawan kyamarori na sCMOS, saboda alakar da ke tsakanin binning da karanta amo.
Idan kana son ƙarin koyo game da EMCCD, da fatan za a danna:
Za a iya Maye gurbin EMCCD kuma Za Mu Taba Son Hakan?
Tucsen Photonics Co., Ltd. Duk haƙƙin mallaka. Lokacin ambato, da fatan za a yarda da tushen:www.tucsen.com
