Lub illuminance meter ntsuas qhov degree uas ib yam khoom yog illuminated, uas yog, qhov piv ntawm cov luminous flux tau nyob rau saum npoo ntawm cov khoom mus rau qhov chaw illuminated. Lub illuminance meter feem ntau yog tsim los ntawm selenium photovoltaic cell los yog silicon photovoltaic cell nrog lub lim thiab microammeter, thiab feem ntau yog siv rau hauv cov chaw pej xeem.
