Measurement Method of LED Brightness
Zoo li cov teeb pom kev zoo ib txwm muaj, qhov ntsuas qhov muag pom ntawm LED qhov chaw teeb pom kev zoo sib xws. Txhawm rau ua kom cov neeg nyeem nkag siab thiab siv tau yooj yim, cov kev paub cuam tshuam yuav raug qhia luv luv hauv qab no:
1. Luminous flux
Luminous flux yog hais txog tus nqi ntawm lub teeb tawm los ntawm lub teeb ci hauv ib lub sijhawm, uas yog, ib feem ntawm lub zog hluav taws xob uas lub zog hluav taws xob tuaj yeem hnov los ntawm tib neeg lub qhov muag. Nws yog sib npaug rau cov khoom ntawm lub zog ntawm lub zog ntawm ib qho band ib lub sij hawm thiab cov txheeb ze saib tus nqi ntawm cov qhab no. Txij li thaum tib neeg lub qhov muag muaj qhov sib txawv ntawm cov txheeb ze saib cov nqi ntawm lub teeb ntawm qhov sib txawv wavelengths, thaum lub zog hluav taws xob ntawm lub teeb ntawm qhov sib txawv wavelengths sib npaug, lub luminous flux tsis sib npaug. Lub cim ntawm luminous flux yog Φ, thiab chav tsev yog lumens (Lm).
Raws li spectral radiant flux Φ (λ), luminous flux formula tuaj yeem muab tau:
Φ=Km■Φ(λ)gV(λ)dλ
Hauv cov mis, V (λ) - txheeb ze spectral luminous efficiency; Km-tus nqi siab tshaj plaws ntawm radiated spectral luminous efficiency, nyob rau hauv Lm / W. Xyoo 1977, tus nqi Km tau txiav txim los ntawm Pawg Neeg Saib Xyuas Kev Nyuaj Siab thiab Kev Ntsuas rau 683Lm / W (λm = 555nm).
2. Lub teeb siv
Lub teeb siv lub teeb yog hais txog lub teeb lub zog dhau los ntawm ib cheeb tsam hauv ib chav tsev. Lub zog yog proportional rau qhov zaus thiab yog cov sum ntawm lawv intensities (xws li ib qho). Nws kuj tseem tuaj yeem nkag siab tias qhov luminous siv I ntawm lub teeb ci nyob rau hauv ib qho kev taw qhia yog lub teeb qhov chaw Lub quotient ntawm lub luminous flux d Φ kis nyob rau hauv lub kaum sab xis lub voos xwmfab nyob rau hauv cov kev taw qhia muab faib los ntawm lub kaum sab xis lub voos xwmfab d Ω.
Chav tsev ntawm luminous siv yog candela (cd), 1cd = 1Lm / 1sr. Cov sum ntawm lub teeb siv nyob rau hauv tag nrho cov lus qhia nyob rau hauv qhov chaw yog lub luminous flux.
3. Kev ci ntsa iab
Hauv peb cov txheej txheem ntawm kev ntsuas qhov ci ntawm LED chips thiab ntsuas kev nyab xeeb ntawm LED lub teeb hluav taws xob, kev siv cov duab feem ntau yog siv, thiab cov duab microscopic tuaj yeem siv los ntsuas cov nti kuaj. Luminous brightness yog brightness L ntawm ib qho chaw ntawm lub teeb-emitting nto ntawm lub teeb qhov chaw, uas yog lub quotient ntawm lub luminous siv ntawm lub ntsej muag ntsiab d S nyob rau hauv ib tug muab kev taw qhia muab faib los ntawm thaj tsam ntawm lub ntsej muag lub ntsiab orthographic projection ntawm ib lub dav hlau perpendicular mus rau qhov muab kev taw qhia
Chav tsev ntawm qhov ci yog candela ib square meter (cd / m2). Thaum lub teeb-emitting nto yog perpendicular rau kev ntsuas kev taw qhia, cosθ = 1.
4. Teeb pom kev zoo
Illumination yog hais txog lub degree uas ib yam khoom yog illuminated, qhia los ntawm lub luminous flux tau txais ib chav tsev. Lub illuminance muaj feem xyuam rau lub teeb pom kev zoo, lub teeb ci ntsa iab thiab qhov chaw ntawm lub teeb ci hauv qhov chaw. Qhov loj yog proportional rau qhov siv ntawm lub teeb qhov chaw thiab qhov teeb meem lub kaum sab xis ntawm lub teeb, thiab inversely proportional rau lub square ntawm qhov kev ncua deb ntawm lub teeb qhov chaw mus rau qhov chaw ntawm lub illuminated khoom. Lub illuminance E ntawm ib qho taw tes ntawm qhov chaw yog qhov quotient ntawm luminous flux d Φ teeb meem ntawm lub vaj huam sib luag uas muaj cov ntsiab lus faib los ntawm thaj tsam ntawm lub vaj huam sib luag d S.
Luas (LX), 1LX = 1Lm/m2.