Electronic multimeter los ntsuas qhov tam sim no ntawm LED tig teeb liab (zoo tib yam lub teeb emitting diode)
Yuav ua li cas ntsuas qhov tam sim no ntawm LED tig teeb liab nrog hluav taws xob multimeter
Vim yog cov yam ntxwv ntawm LED teeb, lub teeb pom kev zoo tam sim no yuav tsum tsis tshua muaj hluav taws xob ncaj qha tam sim no, yog li cov iav ntawm digital multimeter yuav tsum tau teeb tsa rau DC tam sim no txoj hauj lwm, thiab tom qab ntawd pom cov lus qhia DC rectified ntawm LED teeb lub rooj tsavxwm, disconnect nws. , thiab tom qab ntawd tig cov digital Cov kev ntsuam xyuas ntawm cov multimeter txuas nrog lub pob tawg hauv cov koob, thiab cov teeb ci LED tau teeb tom qab lub hwj chim qhib. Lub sijhawm no, tam sim no tso tawm los ntawm multimeter yog tag nrho cov ntws. Faib tag nrho cov ntws los ntawm tus naj npawb ntawm LED teeb kom tau txais tus nqi tam sim no ntawm txhua lub teeb LED. Piv txwv li: Tag nrho cov nqi ntws yog 1 mA (sib npaug rau 1000 microamps), thiab tus naj npawb ntawm LED teeb yog 100, ces 1000÷100=10 (microamperes), uas yog, tam sim no dhau los ntawm txhua lub teeb LED yog 10 microamperes. Sim nws. (Thov xyuam xim rau kev nyab xeeb, qhov hluav taws xob yog 220v ua ntej kho)
Lub teeb-emitting diode (LED) yog lub teeb-emitting ntaus ntawv uas ncaj qha txhaj tam sim no. Nws yog qhov tshwm sim ntawm emitting photons thaum lub zog electrons nyob rau hauv lub semiconductor siv lead ua rov qab los ntawm qib siab zog mus rau qib qis zog. Qhov no feem ntau hu ua kev hloov pauv hloov pauv hloov pauv. Thaum lub LED Lub PN hlws ris yog siv nrog rau pem hauv ntej kev tsis ncaj ncees, thiab cov neeg nqa khoom tsawg thiab cov neeg nqa khoom feem ntau (electrons thiab qhov) recombine thiab emit lub teeb. Nws yog ib nqi sau cia hais tias rau ib tug loj tus naj npawb ntawm hais nyob rau hauv siab zog, txhua spontaneously emits ib tug kab ntawm angular frequencies Nws yog lub teeb nthwv dej ntawm ν=Eg / h, tab sis tsis muaj ib tug taag theem kev sib raug zoo ntawm cov kab. ntawm lub teeb nthwv dej, thiab tuaj yeem muaj qhov sib txawv polarization cov lus qhia, thiab lub teeb tawm los ntawm txhua qhov particle propagates raws tag nrho cov lus qhia tau. Cov txheej txheem no hu ua spontaneous emission. Nws emission wavelength tuaj yeem qhia tau los ntawm cov qauv hauv qab no: λ(μm)=1.2396/Eg(eV)
Lub teeb-emitting diodes (LEDs) feem ntau yog ua los ntawm cov ntaub ntawv xws li gallium arsenide phosphide thiab gallium phosphide. Muaj PN hlws ris hauv nws, uas kuj muaj unidirectional conductivity, tab sis lub teeb-emitting diode yuav emit lub teeb thaum nws tab tom ua rau pem hauv ntej, thiab lub brightness ntawm lub teeb yuav nce nrog rau qhov nce ntawm cov conduction tam sim no, thiab cov xim ntawm lub teeb. lub teeb muaj feem xyuam nrog lub wavelength.
Multimeter nrhiav txoj hauv kev rau lub teeb-emitting diodes zoo tib yam:
1. Siv cov ntaub ntawv R × 10K ntawm multimeter los ntsuas
Siv lub pointer multimeter nrog × 10kΩ thaiv tuaj yeem txiav txim siab seb lub teeb pom kev zoo yog qhov zoo lossis tsis zoo. Feem ntau, qhov kev tiv thaiv pem hauv ntej ntawm lub diode yog kaum rau 200kΩ, thiab qhov rov qab ua haujlwm yog ∝. Yog tias tus nqi tiv thaiv pem hauv ntej yog 0 lossis ∞, thiab tus nqi rov qab yog me me lossis 0, nws yooj yim rau kev puas tsuaj. Nrog rau txoj kev tshawb pom no, lub luminescence ntawm lub luminescent raj tsis tuaj yeem pom ntawm qhov chaw, vim hais tias lub × 10kΩ thaiv tsis tuaj yeem muab qhov loj rau pem hauv ntej rau LED.
2. Siv ob lub multimeter los ntsuas
Yog tias koj muaj ob lub pointer multimeters (zoo dua tib tus qauv), koj tuaj yeem kuaj xyuas lub teeb-emitting diodes zoo dua.
Txuas ib lub xov hlau los ntawm "ntxiv" ncej ntawm ib qho ntawm cov multimeters mus rau "-" ncej ntawm lwm lub 'meter'.
Qhov seem "-" cwjmem txuas nrog rau qhov zoo electrode (P cheeb tsam) ntawm lub luminous raj nyob rau hauv kev sim, thiab qhov seem "ntxiv" cwjmem txuas nrog rau qhov tsis zoo electrode (N cheeb tsam) ntawm lub luminous raj nyob rau hauv kev sim. Ob lub multimeter yog teem rau × 10Ω thaiv.
Raws li ib txwm muaj, nws tuaj yeem tawm teeb pom kev ib txwm muaj tom qab txuas nrog. Yog tias qhov ci ntsa iab qis heev lossis txawm tsis tawm lub teeb, ob qho tib si multimeters tuaj yeem hu mus rau × 1Ω. Yog tias nws tseem tsaus heev lossis txawm tsis tawm lub teeb, nws txhais tau hais tias kev ua haujlwm ntawm lub teeb-emitting diode tsis zoo lossis puas.
Nco ntsoov tias ob lub multimeters tsis tuaj yeem muab tso rau hauv × 1Ω thaum pib ntawm qhov ntsuas, txhawm rau zam dhau qhov tam sim no thiab ua rau lub teeb emitting diodes puas.
3. Kev ntsuas hluav taws xob sab nraud
Cov yam ntxwv kho qhov muag thiab hluav taws xob ntawm lub teeb-emitting diodes tuaj yeem ntsuas tau ntau dua nrog 3V tswj qhov chaw lossis ob lub roj teeb qhuav hauv series thiab multimeter (xws li pointer lossis digital).
