What is Lumen (unit)?
The '''lumen''' (symbol: '''lm''') is the [[SI derived unit]] for brightness. It is defined as 1 [[candela]] times 1 [[steradian]]. One lumen is about a twelfth the brightness of a candle, so a candle has a brightness of around 12 lumens. [[File:V-LIGHT A314.JPG|thumb|It says on the package that this lightbulb makes 470 lumens.]] <br />{{SI units}} [[Category:SI derived units]]