Indlela yokunciphisa ingxolo yezixhobo zokubona iifoto

Indlela yokunciphisa ingxolo yezixhobo zokubona iifoto

Ingxolo yezixhobo zokubona iifoto ibandakanya ikakhulu: ingxolo yangoku, ingxolo yobushushu, ingxolo yokudubula, ingxolo ye-1/f kunye nengxolo ye-wideband, njl. Olu hlulo luyinto enzima kakhulu. Ngeli xesha, siza kwazisa iimpawu zengxolo ezineenkcukacha kunye nohlulo ukunceda wonke umntu aqonde ngcono impembelelo yeentlobo ezahlukeneyo zengxolo kwimiqondiso yemveliso yezixhobo zokubona iifoto. Kuphela ngokuqonda imithombo yengxolo apho sinokuthi sinciphise kwaye siphucule ingxolo yezixhobo zokubona iifoto, ngaloo ndlela siphucule umlinganiselo wesignali-kwingxolo yenkqubo.

Ingxolo yokudubula kukuguquguquka okungacwangciswanga okubangelwa bubuntu obuhlukeneyo babathwali betshaja. Ingakumbi kwisiphumo se-photoelectric, xa ii-photon zibetha izinto ezibonisa ukukhanya ukuze zenze ii-electron, ukuveliswa kwezi electron kwenzeka ngokungacwangciswanga kwaye kuhambelana nokusasazwa kwePoisson. Iimpawu ze-spectral zengxolo yokudubula zithe tyaba kwaye azixhomekekanga kubukhulu be-frequency, kwaye ke ngoko ikwabizwa ngokuba yingxolo emhlophe. Inkcazo yezibalo: Ixabiso le-root mean square (RMS) yengxolo yokudubula linokubonakaliswa ngolu hlobo:

Phakathi kwabo:

e: Itshaja ye-elektroniki (malunga ne-1.6 × 10-19 coulombs)

Idark: Umsinga omnyama

Δf: I-bandwidth

Ingxolo yeshothi ihambelana nobukhulu bombane kwaye izinzile kuzo zonke iifrequencies. Kwifomyula, i-Idark imele umbane omnyama we-photodiode. Oko kukuthi, xa kungekho kukhanya, i-photodiode inomsindo omnyama ongafunekiyo. Njengoko ingxolo engaphakathi kwisiphelo esingaphambili se-photodetector, okukhona umbane omnyama umkhulu, kokukhona ingxolo ye-photodetector inkulu. Umbane omnyama uchaphazeleka yi-voltage yokusebenza ye-bias ye-photodiode, oko kukuthi, xa umbane usebenza we-bias umkhulu, umbane omnyama umkhulu. Nangona kunjalo, i-voltage yokusebenza ye-bias ikwachaphazela amandla okuhlangana kwe-photodetector, ngaloo ndlela ichaphazela isantya kunye ne-bandwidth ye-photodetector. Ngaphezu koko, xa umbane usebenza we-bias umkhulu, isantya kunye ne-bandwidth inkulu. Ke ngoko, ngokwengxolo yeshothi, umbane omnyama kunye nokusebenza kwe-bandwidth ye-photodiode, uyilo olufanelekileyo kufuneka lwenziwe ngokweemfuno zeprojekthi zokwenyani.

2. Ingxolo ekhawulezayo ye-1/f

Ingxolo ye-1/f, eyaziwa ngokuba yingxolo yokutshaza, yenzeka ikakhulu kuluhlu olusezantsi kwaye inxulumene nezinto ezifana neziphene zezinto okanye ukucoceka komphezulu. Ukusuka kumzobo wayo weempawu ze-spectral, kunokubonwa ukuba uxinano lwayo lwamandla e-spectral luncinci kakhulu kuluhlu oluphezulu kunakuluhlu oluphantsi, kwaye xa iphindaphindwa ka-100, ingxolo yoxinano lwe-spectral iyancipha ngokuthe ngqo ngamaxesha ali-10. Uxinano lwamandla e-spectral yengxolo ye-1/f luhambelana ngokuphambeneyo ne-frequency, oko kukuthi:

Phakathi kwabo:

SI(f) : Uxinano lwamandla esandi

I: Okwangoku

f: Ukuphindaphinda

Ingxolo ye-1/f ibalulekile kuluhlu lwe-low-frequency kwaye iyancipha njengoko i-frequency isanda. Olu phawu lwenza ukuba ibe ngumthombo omkhulu wokuphazamiseka kwizicelo ze-low-frequency. Ingxolo ye-1/f kunye nengxolo ye-wideband ikakhulu zivela kwingxolo ye-voltage ye-operating amplifier ngaphakathi kwi-photodetector. Kukho eminye imithombo emininzi yengxolo echaphazela ingxolo ye-photodetectors, njengengxolo yombane ye-operating amplifiers, ingxolo yangoku, kunye nengxolo yobushushu yenethiwekhi yokumelana ekuzuzeni iisekethe ze-operating amplifier.

3. Ingxolo yeVolthi kunye neyangoku ye-amplifier yokusebenza: Ubuninzi be-voltage kunye neyangoku ye-spectral buboniswe kumfanekiso olandelayo:

Kwisekethe ze-amplifier ezisebenzayo, ingxolo yangoku yahlulwe yaba yingxolo yangoku yesigaba kunye nengxolo yangoku eguqukayo. Ingxolo yangoku yesigaba i+ idlula kwi-source internal resistance Rs, ivelisa ingxolo yangaphakathi ye-voltage efanayo u1= i+*Rs. I- Ingxolo yangoku eguqukayo idlula kwi-gain equal resistor R ukuvelisa ingxolo yamandla efanayo u2= I-* R. Ngoko ke xa i-RS yombane inkulu, ingxolo yamandla eguqulwe kwingxolo yangoku nayo inkulu kakhulu. Ke ngoko, ukuze ilungelelanise ingxolo engcono, ingxolo yamandla (kuquka ukumelana kwangaphakathi) nayo yindlela ephambili yokwenza ngcono. Uxinano lwe-spectral yengxolo yangoku ayitshintshi ngokutshintsha kwamaza. Ke ngoko, emva kokuba ikhuliswe yisekethe, yona, njengomsinga omnyama we-photodiode, yenza ngokupheleleyo ingxolo yokudubula ye-photodetector.

4. Ingxolo yobushushu yenethiwekhi yokumelana ne-gain (i-amplification factor) yesekethe ye-amplifier yokusebenza ingabalwa kusetyenziswa le fomyula ilandelayo:

Phakathi kwabo:

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

T: Ubushushu obupheleleyo (K)

R: Ingxolo yobushushu yeResistance (ohms) inxulumene nexabiso lobushushu kunye nelokumelana, kwaye i-spectrum yayo ithambile. Kunokubonwa kwifomyula ukuba ixabiso lokumelana ne-gain lilikhulu, ingxolo yobushushu iyanda. Okukhona i-bandwidth inkulu, ingxolo yobushushu iya kuba nkulu. Ke ngoko, ukuqinisekisa ukuba ixabiso lokumelana kunye nexabiso le-bandwidth ziyahlangabezana neemfuno ze-gain kunye neemfuno ze-bandwidth, kwaye ekugqibeleni zifuna ingxolo ephantsi okanye i-signal-to-noise ratio ephezulu, ukukhethwa kwee-gain resistor kufuneka kuqwalaselwe ngononophelo kwaye kuvavanywe ngokusekelwe kwiimfuno zeprojekthi zokwenyani ukuze kufezekiswe i-signal-to-noise ratio efanelekileyo yenkqubo.

Isishwankathelo

Itekhnoloji yokuphucula ingxolo idlala indima ebalulekileyo ekuphuculeni ukusebenza kwezixhobo zokubona iifoto kunye nezixhobo ze-elektroniki. Ukuchaneka okuphezulu kuthetha ingxolo ephantsi. Njengoko itekhnoloji ifuna ukuchaneka okuphezulu, iimfuno zengxolo, umlinganiselo wesignali-kwingxolo, kunye namandla engxolo alinganayo ezixhobo zokubona iifoto nazo ziya ziphakama.