Lux is the illumination unit1lux =1lumen/m21CD (candle light), which refers to the luminous intensity of a completely radiated object every sixtieth square centimeter at the freezing point temperature of platinum. (It used to refer to a whale oil candle with a diameter of 2.2 cm and a mass of 75.5 g, which burns 7.78 g per hour, the flame height is 4.5 cm, and the luminous intensity in the horizontal direction) 1L (lumen) refers to the luminous flux of 1 CD candle on the plane with a distance 1cm and an area 1cm. 1Lux means that the luminous flux of 1L is evenly distributed on the area of 1M2. This is too professional. Anyway, I don't think that street lamp is very bright.