Lub illuminometer (los yog lux meter) yog ib qho cuab yeej uas ntsuas luminosity thiab brightness. Nws muaj ib tug tswv tsev thiab lub teeb sensor. Qhov ntsuas ntsuas yog 0-50000. Qhov nruab nrab sab hauv tsev teeb pom kev zoo yog los ntawm 100-1000lux, thiab lub hnub ci sab nraum zoov yog li 50000lux. lux yog ib chav tsev ntawm illuminance uas qhia qhov ceev ntawm lub teeb ci rau ntawm qhov chaw. Nws cov ntawv thov feem ntau yog sab hauv tsev, chaw ua haujlwm, chaw soj nstuam, thiab kev tshawb fawb ib puag ncig.
