Mokhoa oa ho fokotsa lerata la li-photodetectors

Mokhoa oa ho fokotsa lerata la li-photodetectors

Lerata la li-photodetectors haholo-holo le kenyelletsa: lerata la hona joale, lerata la mocheso, lerata la ho thunngoa, lerata la 1/f le lerata le pharaletseng, joalo-joalo. Lekhetlong lena, re tla hlahisa lintlha tse qaqileng haholoanyane tsa lerata le likarolo ho thusa motho e mong le e mong ho utloisisa hamolemo tšusumetso ea mefuta e fapaneng ea lerata ho mats'oao a tlhahiso ea li-photodetectors. Ke feela ka ho utloisisa mehloli ea lerata re ka fokotsang le ho ntlafatsa lerata la li-photodetectors, ka tsela eo, re ntlafatsa karo-karolelano ea lerata ho ea tsamaiso.

Lerata la Shot ke ho feto-fetoha ho sa reroang ho bakoang ke mofuta o ikhethileng oa bajari ba litefiso. Haholo-holo ka phello ea photoelectric, ha li-photon li otla likarolo tsa photosensitive ho hlahisa li-electrone, tlhahiso ea li-electrone tsena e etsahala ka tšohanyetso 'me e lumellana le kabo ea Poisson. Litšobotsi tsa spectral tsa lerata la ho thunngoa li bataletse ebile li ikemela ka boholo ba makhetlo a mangata, kahoo e boetse e bitsoa lerata le lesoeu. Tlhaloso ea lipalo: Motso oa lisekoere (RMS) boleng ba lerata la sethunya le ka hlalosoa ka tsela e latelang:

Har'a bona:

e: Tefiso ea elektronike (hoo e ka bang 1.6 × 10-19 coulombs)

Idark: Nako e lefifi

Δf: Bophahamo ba moeli

Lerata la ho thunngoa le lekana le boholo ba hona joale 'me le tsitsitse ka linako tsohle. Ka foromo, Idark e emela khanya e lefifi ea photodiode. Ke hore, ha ho se na leseli, photodiode e na le lerata le sa batleheng le lefifi la hona joale. E le lerata la tlhaho karolong e ka pele ea photodetector, lerata le leholo le lefifi, lerata le leholo la photodetector. Lefifi la hona joale le boetse le angoa ke matla a ho sebetsa a leeme a photodiode, ke hore, ha matla a ts'ebetso a leeme a le kholoanyane, ho na le matla a mangata a lefifi. Leha ho le joalo, matla a ho sebetsa a leeme a boetse a ama matla a mateano a photodetector, kahoo a susumetsa lebelo le bandwidth ea photodetector. Ho feta moo, ha matla a leeme a eketseha, lebelo le bandwidth le eketseha. Ka hona, mabapi le lerata la ho thunngoa, ts'ebetso e lefifi ea hona joale le li-bandwidth tsa photodiode, moralo o utloahalang o lokela ho etsoa ho latela litlhoko tsa sebele tsa morero.

2. 1/f Lerata la Flicker

Lerata la 1/f, leo hape le tsejwang e le lerata le hlabang, le etsahala haholo sebakeng sa maqhubu a tlase mme le amana le dintho tse kang bofokodi ba thepa kapa bohlweki ba bokahodimo. Ho latela sets'oants'o sa eona sa sebopeho sa spectral, ho ka bonoa hore matla a eona a spectral density e nyane haholo sebakeng sa maqhubu a phahameng ho feta a maqhubu a tlase, 'me bakeng sa keketseho e' ngoe le e 'ngoe ea makhetlo a 100, lerata la spectral density le fokotseha ka makhetlo a 10. Matla a spectral density ea 1/f lerata e fapana ka tsela e fapaneng le frequency, ke hore:

Har'a bona:

SI(f) : Matla a lerata a spectral density

Ke: Hona joale

f: Hangata

Lerata la 1/f le bohlokoa sebakeng sa maqhubu a tlase 'me lea fokola ha maqhubu a ntse a eketseha. Tšobotsi ena e etsa hore e be mohloli o moholo oa tšitiso lits'ebetsong tse fokolang khafetsa. Lerata la 1/f le lerata la wideband haholo-holo li tsoa lerata la motlakase oa amplifier e sebetsang ka har'a photodetector. Ho na le mehloli e meng e mengata ea lerata e amang lerata la li-photodetectors, tse kang lerata la phepelo ea matla a li-amplifiers tse sebetsang, lerata la hona joale, le lerata la mocheso oa marang-rang a ho hanyetsa molemong oa lipotoloho tsa amplifier tse sebetsang.

3. Lerata la motlakase le la hona joale la amplifier ea ts'ebetso: Matla a motlakase le a hona joale a spectral densities a bontšoa setšoantšong se latelang:

Lipotolohong tsa amplifier tse sebetsang, lerata la hona joale le arotsoe ka lerata la hona joale la karolo le lerata le feto-fetohang. Lerata la hona joale la in-phase i + le phalla ka har'a mohloli oa ho hanyetsa ka hare ho Rs, ho hlahisa molumo o lekanang oa voltage u1 = i +*Rs. I- Inverting lerata la hona joale le phalla ka phaello e lekanang le resistor R ho hlahisa molumo o lekanang oa voltage u2 = I-* R. Kahoo ha RS ea phepelo ea matla e le khōlō, lerata la motlakase le fetoletsoeng ho tloha lerata la hona joale le lona le leholo haholo. Ka hona, ho ntlafatsa lerata le betere, lerata la phepelo ea motlakase (ho kenyeletsoa ho hanyetsa ka hare) le eona ke tataiso ea bohlokoa bakeng sa ntlafatso. Boima ba spectral ba lerata la hona joale ha bo fetohe le ho fapana ha maqhubu le hona. Ka hona, ka mor'a ho matlafatsoa ke potoloho, eona, joalo ka maqhubu a lefifi a photodiode, e etsa ka mokhoa o pharaletseng lerata la ho thunngoa la photodetector.

4. Lerata le chesang la marang-rang a ho hanyetsa bakeng sa phaello (amplification factor) ea potoloho ea amplifier e sebetsang e ka baloa ka mokhoa o latelang:

Har'a bona:

k: Boltzmann kamehla (1.38 × 10-23J/K)

T: Mocheso o Feletseng (K)

R: Resistance (ohms) lerata la mocheso le amana le mocheso le boleng ba ho hanyetsa, 'me ponahalo ea eona e bataletse. E ka bonoa ho tsoa ho mokhoa oa hore boleng bo phahameng ba ho hanyetsa, lerata le leholo la mocheso. Ha bandwidth e le kholoanyane, lerata le leholo la mocheso le lona le tla ba teng. Ka hona, ho etsa bonnete ba hore boleng ba ho hanyetsa le boleng ba bandwidth bo kopana le litlhoko tsa phaello le litlhoko tsa bandwidth, 'me qetellong hape bo batla lerata le tlase kapa tekanyo e phahameng ea lerata-ho-lerata, khetho ea bahanyetsi ba phaello e hloka ho nahanoa ka hloko le ho hlahlojoa ho ipapisitsoe le litlhoko tsa projeke ea nnete ho fihlela tekanyo e nepahetseng ea lerata le lerata la sistimi.

Kakaretso

Theknoloji ea ntlafatso ea lerata e bapala karolo e kholo ho ntlafatseng ts'ebetso ea li-photodetectors le lisebelisoa tsa elektroniki. Ho nepahala ho phahameng ho bolela lerata le tlase. Ha thekenoloji e batla ho nepahala ho holimo, litlhoko tsa lerata, karo-karolelano ea lerata, le matla a lekanang a lerata la li-photodetectors le tsona li ntse li phahama.