22/07/13I-Time Delay Integration (TDI) iwuhlelo lokuthwebula izithombe olubikezela kusengaphambili ukuthwebula kwedijithali - kodwa lokho kusahlinzeka ngezinzuzo ezinhle kakhulu ekugcineni kwezithombe namuhla. Kunezimo ezimbili lapho amakhamera e-TDI angakhanya khona - womabili lapho isihloko sesithombe sinyakaza:
1 – Isihloko sesithombe sinyakaza ngokwemvelo ngesivinini esingaguquki, njengasekuhlolweni kwewebhu (njengokuskena amashidi anyakazayo ephepha, ipulasitiki noma indwangu ukuze kutholwe amaphutha nomonakalo), imigqa yokuhlanganisa, noma ama-micro fluidics nokugeleza koketshezi.
2 – Izihloko zokuthatha izithombe ezimile ezingathwetshulwa yikhamera zisuka endaweni ziye endaweni, ngokususa isihloko noma ikhamera. Izibonelo zifaka ukuskena kwesilayidi ngesibonakhulu, ukuhlolwa kwezinto, ukuhlolwa kwephaneli eyisicaba njll.
Uma noma esinye salezi zimo singasebenza ekucabangeni kwakho, leli khasi lewebhu lizokusiza ukuthi ucabangele ukuthi ukushintsha ukusuka kumakhamera 'weskeni lendawo' enezinhlangothi ezi-2 kuya kumakhamera we-Line Scan TDI kungase kunikeze isithombe sakho amandla.
Inkinga nge-Area-Scan & Moving Targets
● Ukufiphalisa Ukunyakaza
Ezinye izihloko zezithombe zihamba ngokwesidingo, isibonelo ekugelezeni kwamanzi noma ekuhlolweni kwewebhu. Kwezinye izinhlelo zokusebenza, njengokuskena kwamaslayidi nokuhlolwa kwezinto, ukugcina isihloko sinyakaza kungashesha kakhulu futhi kusebenze kahle kakhulu kunokumisa ukunyakaza kwesithombe ngasinye esitholiwe. Nokho, kumakhamera wokuskena endaweni, uma isihloko sesithombe sinyakaza ngokuhlobene nekhamera, lokhu kungase kuveze inselele.
Ukufiphala kokunyakaza okuhlanekezela isithombe semoto ehambayo
Ezimeni ezinokukhanya okulinganiselwe noma lapho izimfanelo zesithombe eziphakeme zidingeka khona, isikhathi eside sokuchayeka kwekhamera singadingeka. Nokho, ukunyakaza kwesihloko kuzosabalalisa ukukhanya kwakho phezu kwamaphikseli ekhamera amaningi ngesikhathi sokuchayeka, okuholela 'ekufiphaleni kokunyakaza'. Lokhu kungancishiswa ngokugcina ukuchayeka kufushane kakhulu -ngaphansi kwesikhathi obekungasithatha iphoyinti esihlokweni ukunqamula iphikseli yekhamera. Lena yi-unngokuvamile ngezindleko zezithombe ezimnyama, ezinomsindo, ngokuvamile ezingasebenziseki.
●Ukuthunga
Ukwengeza, ukuthwebula izithombe ngezihloko ezinkulu noma eziqhubekayo ngamakhamera okuskena endawo kudinga ukutholwa kwezithombe eziningi, ezibe sezihlanganiswa. Lokhu kuthunga kudinga amaphikseli agqagqene phakathi kwezithombe ezingomakhelwane, ukunciphisa ukusebenza kahle nokukhulisa ukugcinwa kwedatha nezimfuneko zokucubungula.
●Ukukhanya okungalingani
Ngaphezu kwalokho, ukukhanya ngeke kwanele ngokwanele ukugwema izinkinga nezinto zobuciko emingceleni ephakathi kwezithombe ezithungiwe. Futhi, ukuhlinzeka ngokukhanya endaweni enkulu eyanele yekhamera ethwebula indawo enamandla okwanele ngokuvamile kudinga ukusetshenziswa kwamandla aphezulu, imithombo yokukhanya ye-DC ebiza kakhulu.
Ukukhanya okungalingani ekuthungeni ukutholwa kwezithombe eziningi zobuchopho begundane. Isithombe esivela ku-Watson et al. 2017: http://dx.doi.org/10.1371/journal.pone.0180486
Iyini ikhamera ye-TDI, futhi isiza kanjani?
Kumakhamera avamile we-2-dimensional area-scan, kunezigaba ezintathu zokuthola isithombe: ukusetha kabusha kwe-pixel, ukuchayeka, nokufunda. Ngesikhathi sokuchayeka, ama-photon avela endaweni yesehlakalo ayatholakala, okuholela kuma-photoelectrons, agcinwa kumaphikseli ekhamera kuze kube sekupheleni kokuchayeka. Amanani asuka kuwo wonke amaphikseli abe esefundwa, bese kwakheka isithombe esingu-2D. Amaphikseli abe esehlelwa kabusha futhi zonke izindleko ziyasulwa ukuze kuqalwe ukuchayeka okulandelayo.
Kodwa-ke, njengoba kushiwo, uma isihloko sesithombe sihamba ngokuhlobene nekhamera, ukukhanya okuvela esihlokweni kungasakazeka kumaphikseli amaningi phakathi nalokhu kuvezwa, okuholela ekufiphaleni kokunyakaza. Amakhamera e-TDI anqoba lo mkhawulo esebenzisa indlela emisha. Lokhu kuboniswa ku-[Animation 1].
●Asebenza kanjani amakhamera we-TDI
Amakhamera we-TDI asebenza ngendlela ehluke kakhulu ekuthwebuleni amakhamera endaweni. Njengoba isihloko sesithombe sinyakaza kukhamera ngesikhathi sokuchayeka, amanani e-elekthronikhi akha isithombe esitholiwe nawo ayasuswa, ahlale ekuvumelanisa. Ngesikhathi sokuchayeka, amakhamera e-TDI ayakwazi ukushova wonke amanani atholiwe ukusuka kumugqa owodwa wamaphikseli ukuya kolandelayo, eduze kwekhamera, ehambisana nokunyakaza kwesihloko sokuthwebula isithombe. Njengoba isihloko sinqamula ikhamera, irowu ngayinye (eyaziwa ngokuthi 'Isiteji se-TDI'), inikeza ithuba elisha lokudalula ikhamera esihlokweni, nokuqongelela isignali.
Uma umugqa wezindleko ezitholiwe ufika ekugcineni kwekhamera, yilapho kuphela amanani afundwa aphinde agcinwe njengocezu olunohlangothi olu-1 lwesithombe. Isithombe se-2-D sakhiwe ngokunamathela ndawonye ucezu ngalunye lwesithombe njengoba ikhamera isifunda. Umugqa ngamunye wamaphikseli kumathrekhi esithombe angumphumela nemifanekiso 'ucezu' olufanayo lwesihloko sokuthwebula, okusho ukuthi ngaphandle kokunyakaza, akukho ukufiphala.
●256x Ukuchayeka Okude
Ngamakhamera e-TDI, isikhathi sokuchayeka esisebenzayo sesithombe sinikezwa sonke isikhathi esisithathayo ukuze uthole iphuzu esihlokweni ukunqamula yonke imigqa yamaphikseli, nezigaba ezifika kwezingu-256 ezitholakala kwamanye amakhamera e-TDI. Lokhu kusho ukuthi isikhathi esitholakalayo sokuchayeka sikhulu izikhathi ezingama-256 kunalokho okungatholwa yikhamera yendawo.
Lokhu kungaletha ukuthuthukiswa okubili, noma ibhalansi yakho kokubili. Okokuqala, ukukhushulwa okukhulu kwejubane lokuthwebula izithombe kungafinyelelwa. Uma kuqhathaniswa nekhamera yendawo yokuskena, isihloko sokuthwebula singahamba sifike ku-256x ngokushesha kuyilapho sithwebula inani elifanayo lesiginali, ukunikezela izinga lomugqa wekhamera lishesha ngokwanele ukuhambisana.
Ngakolunye uhlangothi, uma kudingeka ukuzwela okukhulu, isikhathi eside sokuchayeka singanika amandla izithombe zekhwalithi ephezulu kakhulu, amandla okukhanya aphansi, noma kokubili.
●Ukudluliswa kwedatha enkulu ngaphandle kokuthunga
Njengoba ikhamera ye-TDI ikhiqiza isithombe esingu-2-dimensional kusukela kuzingcezu ze-1-dimensional ezilandelanayo, isithombe esiwumphumela singaba sikhulu njengoba kudingekile. Ngenkathi inani lamaphikseli asendleleni 'evundlile' linikezwa ububanzi bekhamera, isibonelo amaphikseli angu-9072, usayizi 'omile' wesithombe awunamkhawulo, futhi unqunywa kalula ukuthi ikhamera isebenza isikhathi esingakanani. Ngamazinga olayini afika ku-510kHz, lokhu kungaletha idatha enkulu kakhulu.
Ehlanganiswe nalokhu, amakhamera we-TDI anganikeza izinkundla zokubuka ezibanzi kakhulu. Isibonelo, ikhamera yephikseli engu-9072 enamaphikseli angu-5µm inikeza inkambu evundlile yokubuka engu-45mm ngokulungiswa okuphezulu. Ukuze uzuze ububanzi obufanayo bokuthwebula ngekhamera ye-pixel engu-5µm yokuskena indawo kuzodinga amakhamera afika kwamathathu e-4K ngapha nangapha.
●Ukuthuthukiswa kwamakhamera wokuskena komugqa
Amakhamera we-TDI awanikezi nje ukuthuthukiswa kwamakhamera endawo. Amakhamera wokuskena ngomugqa, athwebula umugqa owodwa nje wamaphikseli, nawo ahlushwa yizinkinga eziningi ezifanayo ngokugqama kokukhanya kanye nokuchayeka okufushane njengamakhamera esikena endawo.
Nakuba njengamakhamera we-TDI, amakhamera we-line scan anikeza ukukhanya okwengeziwe ngokusetha okulula, futhi agweme isidingo sokuthungwa kwesithombe, ngokuvamile angadinga ukukhanya okunamandla kakhulu kanye/noma ukunyakaza kwesihloko okunensayo ukuze athwebule isignali eyanele yesithombe sekhwalithi ephezulu. Ukuchayeka okude kanye nesivinini sesifundo esisheshayo esivunyelwa amakhamera we-TDI kusho ukuqina okuphansi, ukukhanyisa kwezindleko eziphansi kungasetshenziswa ngenkathi kuthuthukiswa ukusebenza kahle kwesithombe. Isibonelo, ulayini wokukhiqiza ungase ukwazi ukusuka emazingeni aphezulu e-halogen abiza kakhulu, asebenzisa amandla aphezulu adinga amandla e-DC, uye ekukhanyeni kwe-LED.
Asebenza kanjani amakhamera e-TDI?
Kunamazinga amathathu ajwayelekile okuthi ungafinyelela kanjani izithombe ze-TDI kunzwa yekhamera.
● I-CCD TDI- Amakhamera e-CCD ayisitayela esidala kakhulu samakhamera edijithali. Ngenxa yedizayini yazo ye-elekthronikhi, ukuzuza ukuziphatha kwe-TDI ku-CCD kulula kakhulu uma kuqhathaniswa, nezinzwa eziningi zamakhamera ezikwazi ukusebenza ngale ndlela ngokwemvelo. Ngakho-ke ama-TDI CCDs asetshenziswe amashumi eminyaka.
Nokho, ubuchwepheshe be-CCD bunemikhawulo yabo. Usayizi wephikseli omncane kakhulu ovame ukutholakala kumakhamera e-CCD TDI cishe u-12µm x 12µm – lokhu, kanye nezibalo zamaphikseli amancane, kukhawulela amakhono amakhamera okuxazulula imininingwane emihle. Ngaphezu kwalokho, isivinini sokutholwa siphansi kunobunye ubuchwepheshe, kuyilapho umsindo ofundwayo– isici esikhawulelayo ekucabangeni kokukhanya okuphansi – siphezulu. Ukusetshenziswa kwamandla nakho kuphezulu, okuyisici esikhulu kwezinye izinhlelo zokusebenza. Lokhu kuholele esifisweni sokudala amakhamera e-TDI asekelwe ekwakhiweni kwe-CMOS.
●I-CMOS TDI yasekuqaleni: Isizinda se-Voltage kanye nesifinyezo sedijithali
Amakhamera e-CMOS anqoba imingcele eminingi yomsindo nesivinini samakhamera e-CCD, kuyilapho esebenzisa amandla amancane, futhi enikeza osayizi bamaphikseli abancane. Nokho, ukuziphatha kwe-TDI bekunzima kakhulu ukuzuza kumakhamera e-CMOS, ngenxa yokwakheka kwawo kwamaphikseli. Ngenkathi ama-CCD anyakazisa ama-photoelectrons ukusuka kwephikseli ukuya kuphikseli ukuze aphathe inzwa, amakhamera e-CMOS aguqula amasiginali kuma-photoelectrons abe ama-voltage kuphikseli ngayinye ngaphambi kokufunda.
Ukuziphatha kwe-TDI kunzwa ye-CMOS kuye kwahlolisiswa kusukela ngo-2001, nokho, inselele yokuthi isingathwa kanjani 'ukuqoqwa' kwesignali njengoba ukuchayeka kunyakaza ukusuka kumugqa owodwa kuya kolandelayo kwakubalulekile. Izindlela ezimbili zakuqala ze-CMOS TDI ezisasetshenziswa kumakhamera wezohwebo namuhla ukuqoqwa kwesizinda se-voltage kanye nokufingqa kwedijithali i-TDI CMOS. Kumakhamera okunqwabelana kwesizinda se-voltage, njengoba umugqa ngamunye wesiginali utholwa njengoba isihloko sesithombe sidlula, i-voltage etholiwe yengezwa nge-elekthronikhi ekutholweni okuphelele kwaleyo ngxenye yesithombe. Ukunqwabelana kwama-voltage ngale ndlela kwethula umsindo owengeziwe wesigaba ngasinye se-TDI esengeziwe esingeziwe, okukhawulela izinzuzo zezigaba ezengeziwe. Izinkinga ezinomugqa ziphinde zibe inselele ekusetshenzisweni kwalawa makhamera ezinhlelweni zokusebenza ezinembile.
Indlela yesibili i-digital summing TDI. Ngale ndlela, ikhamera ye-CMOS isebenza ngempumelelo kumodi yokuskena kwendawo enokuchayeka okufushane kakhulu okufaniswa nesikhathi esithathwe ukuze isihloko sokuthwebula sihambe kumugqa owodwa wamaphikseli. Kodwa, imigqa evela kuhlaka ngalunye olulandelanayo yengezwa ndawonye ngedijithali ngendlela yokuthi umphumela we-TDI ulethwe. Njengoba yonke ikhamera kufanele ifundwe kumugqa ngamunye wamaphikseli esithombeni esiwumphumela, lokhu kwengeza okudijithali futhi kwengeza umsindo ofundwayo womugqa ngamunye, futhi kukhawulele isivinini sokuthola.
●Izinga lesimanje: isizinda sokushaja i-TDI CMOS, noma i-CCD-on-CMOS TDI
Imikhawulo ye-CMOS TDI engenhla inqotshwe kamuva nje ngokwethula i-Charge-domain accumulation TDI CMOS, eyaziwa nangokuthi yi-CCD-on-CMOS TDI. Ukusebenza kwalezi zinzwa kuboniswa ku-[Animation 1]. Njengoba igama lisho, lezi zinzwa zinikeza ukunyakaza okufana ne-CCD kwamashaji kusuka kwephikseli eyodwa kuya kwelandelayo, isignali eqongelelayo esigabeni ngasinye se-TDI ngokungezwa kwama-photoelectrons ezingeni lezindleko zomuntu ngamunye. Lokhu akunamsindo ngempumelelo. Kodwa-ke, imikhawulo ye-CCD TDI iyanqotshwa ngokusebenzisa i-CMOS readout architecture, okuvumela isivinini esikhulu, umsindo ophansi kanye nokusetshenziswa kwamandla okuphansi okuvamile kumakhamera e-CMOS.
Imininingwane ye-TDI: yini ebalulekile?
●Ubuchwepheshe:Isici esibaluleke kakhulu yilokho ubuchwepheshe bezinzwa obusetshenziswa njengoba kuxoxwe ngenhla. I-CMOS TDI yesizinda sokushaja izoletha ukusebenza okuhle kakhulu.
●Izigaba ze-TDI:Leli inani lemigqa yenzwa lapho isignali ingaqoqwa khona. Uma ikhamera iba nezigaba eziningi ze-TDI, isikhathi sayo sokuchayeka siba side kakhulu. Noma, uma isihloko sesithombe singahamba ngokushesha, inqobo nje uma ikhamera inezinga elanele lomugqa.
●Isilinganiso Somugqa:Mingaki imigqa engafundwa ikhamera ngomzuzwana. Lokhu kunquma isivinini esikhulu sokunyakaza ikhamera engakwazi ukuhambisana naso.
●Ukusebenza Kwe-Quantum: Lokhu kubonisa ukuzwela kwekhamera ekukhanyeni ngamaza ahlukene ahlukene, okunikezwe ithuba lokuthi i-photon yesigameko itholwe futhi ikhiqize i-photoelectron. Ukusebenza kahle kwe-quantum okuphezulu kunganikeza amandla okukhanya aphansi, noma ukusebenza okusheshayo ngenkathi kugcinwa amaleveli esignali afanayo.
Ukwengeza, amakhamera ayahluka ngebanga le-wavelength lapho ukuzwela okuhle kungafinyelelwa khona, amanye amakhamera anikeza ukuzwela kuze kube sekupheleni kwe-ultra-violet (UV) ye-spectrum, cishe ku-200nm wavelength.
●Funda Umsindo:Umsindo wokufunda ungenye into ebalulekile ekuzweleni kwekhamera, enquma ubuncane besignali engatholwa ngaphezu komsindo wephansi lekhamera. Ngomsindo ofundeka kakhulu, izici ezimnyama azikwazi ukutholwa futhi ububanzi obuguqukayo buncishiswa kakhulu, okusho ukukhanya okukhanyayo noma izikhathi zokuchayeka ezinde & nesivinini sokunyakaza okuhamba kancane kufanele kusetshenziswe.
Imininingwane ye-TDI: yini ebalulekile?
Njengamanje, amakhamera e-TDI asetshenziselwa ukuhlola iwebhu, ukuhlola izinto zikagesi kanye nokukhiqiza, nezinye izinhlelo zokusebenza zokubona ngomshini. Eceleni kwalokhu kunezinhlelo zokusebenza ezinokukhanya okuphansi eziyinselele ezifana ne-fluorescence imaging kanye nokuskena kwama-slide.
Kodwa-ke, ngokwethulwa kwamakhamera e-TDI CMOS anesivinini esikhulu, umsindo ophansi, azwela kakhulu, kunethuba elikhulu lokunyuka kwesivinini nokusebenza kahle ezinhlelweni ezintsha ebezisebenzisa amakhamera wendawo kuphela. Njengoba sethule ekuqaleni kwe-athikili, amakhamera e-TDI angaba yinketho engcono kakhulu yokuzuza isivinini esiphezulu kanye nezimfanelo zesithombe esiphezulu kunoma iyiphi izihloko ezithatha izithombe ezihamba njalo, noma lapho ikhamera ingase iskenwe kuzo zonke izihloko zesithombe ezimile.
Isibonelo, kuhlelo lokusebenza lwe-microscopy, singaqhathanisa isivinini sokutholwa kwe-theoretical ye-9K pixel, ikhamera ye-TDI yesiteji esingu-256 enamaphikseli angu-5 µm kukhamera yekhamera engu-12MP yendawo enamaphikseli angu-5 µm. Ake sihlole ukuthola indawo engu-10 x 10 mm enokukhulisa okungu-20x ngokuhambisa isiteji.
1. Ukusebenzisa injongo engu-20x ngekhamera yeskeni yendawo kuzoletha inkambu yokubuka yesithombe engu-1.02 x 0.77 mm.
2. Ngekhamera ye-TDI, umgomo we-10x onokukhulisa okwengeziwe okungu-2x ungasetshenziswa ukuze unqobe noma imuphi umkhawulo endaweni yokubuka yesibonakhulu, ukuletha inkambu yokubuka evundlile yesithombe engu-2.3mm.
3. Uma sithatha ukugqagqana kwamaphikseli angu-2% phakathi kwezithombe ngezinjongo zokuthunga, amasekhondi angu-0.5 ukuhambisa isiteji endaweni emisiwe, kanye nesikhathi sokuchayeka esingu-10ms, singabala isikhathi esingasithatha ikhamera yendawo. Ngokufanayo, singakwazi ukubala isikhathi ikhamera ye-TDI ebingasithatha uma isiteji besigcinwa sinyakaza ukuze siskene esiqondisweni esingu-Y, ngesikhathi esifanayo sokuchayeka emugqeni ngamunye.
4. Kulesi simo, ikhamera yendawo yokuskena izodinga izithombe ezingu-140 ukuze zitholwe, namasekhondi angu-63 achithwa unyakazisa isiteji. Ikhamera ye-TDI izothola izithombe ezinde ezi-5 kuphela, kuzochitha imizuzwana emi-2 kuphela ihambisa isiteji kukholamu elandelayo.
5. Isikhathi esiphelele esichithwa kutholwa indawo engu-10 x 10 mm sizobaImizuzwana engu-64.4 yekhamera yendawo yokuskena,futhi njeImizuzwana engu-9.9 yekhamera ye-TDI.
Uma ungathanda ukubona ukuthi ikhamera ye-TDI ingafanisa yini nesicelo sakho futhi ihlangabezane nezidingo zakho, xhumana nathi namuhla.
