relation between the amount of beneficial light emitted and the amount of wasted light
LUMINOUS EFFICIENCY
Meaning of LUMINOUS EFFICIENCY in English
Explanatory English dictionary bed edition. Толковый словарь английского языка Редакция bed. 2012
relation between the amount of beneficial light emitted and the amount of wasted light
Explanatory English dictionary bed edition. Толковый словарь английского языка Редакция bed. 2012