Chav ntsuas ntsuas ntawm illuminance thiab tej yam kev mob ntawm kev siv
Chav nyob rau illuminance meters
Ntau tus neeg muas zaub yuav hais tias, Kuv xav yuav lub teeb 'meter', thiab lawv yuav nug seb lub teeb ntsuas lub teeb yog dab tsi! Tam sim no cia peb luv luv qhia illuminance. Illuminance yog ib chav tsev uas qhia txog kev siv lub teeb. Nws lub cev lub ntsiab lus yog lub luminous flux illuminated ntawm ib cheeb tsam. Chav tsev ntawm illuminance yog tus naj npawb ntawm lumens (Lm) ib square meter, kuj hu ua Lux: 1Lux=1Lm / m2. Raws li tuaj yeem pom los ntawm cov qauv saum toj no, Lm yog chav tsev ntawm luminous flux, uas txhais tau tias yog lub teeb hluav taws xob los ntawm thaj tsam ntawm 1/60 square metres ntawm platinum ntshiab hauv lub kaum sab xis ntawm 1 steradian ntawm qhov kub thiab txias. (kwv yees li 1770 degree).
Cov lus piav qhia saum toj no ntawm illumination units zoo li theoretical heev thiab feem ntau nyuaj rau kev nkag siab. Txhawm rau kom muaj kev nkag siab ntau ntxiv ntawm cov teeb pom kev zoo, piv txwv li, 100W incandescent teeb emits tag nrho cov luminous flux txog 1200Lm. Yog hais tias nws yog assumed tias lub luminous flux yog sib npaug zos rau ib hemisphere, ces qhov kev ncua deb ntawm lub teeb qhov chaw Lub illuminance qhov tseem ceeb ntawm 1m thiab 5m yuav tau raws li nram no cov kauj ruam: cheeb tsam ntawm ib hemisphere nrog ib tug vojvoog ntawm 1m yog 2π. ×12=6.28 m2, thiab tus nqi illuminance ntawm 1m ntawm lub teeb qhov chaw yog: 1200Lm / 6.28 m2=191Lux. Ib yam li ntawd, thaj tsam ntawm ib hemisphere nrog lub vojvoog ntawm 5m yog: 2π × 52=157 m2, thiab tus nqi illumination ntawm qhov deb ntawm 5m ntawm lub teeb qhov chaw yog: 1200Lm / 157 m2=7 .64 Lux.
Cov xwm txheej dav dav: Lub caij ntuj sov, lub teeb pom kev zoo yog li 100000LUX nyob rau hauv lub hnub; sab nraum zoov illuminance nyob rau ib hnub huab cua yog 10000LUX; lub teeb pom kev nyob sab hauv tsev yog 100LUX; qhov illuminance ntawm peb lub desktop 60cm deb ntawm 60W lub rooj teeb yog 300LUX; lub illuminance nyob rau hauv lub TV nyob broadcast chav tsev yog 1000LUX; hauv chav thaum tsaus ntuj Lub teeb pom kev zoo yog 10LUX; qhov illuminance ntawm txoj kev teeb thaum hmo ntuj yog 0.1LUX; qhov illuminance ntawm tswm ciab (ntawm qhov deb ntawm 20cm) yog 10 ~ 15LUX.
