勒克斯（Lux，通常简写为lx）是一个标识照度的国际单位制单位，1流明每平方米面积，就是1勒克斯。

其单位换算是1勒克斯 = 1 流明/平方米 = 1 坎德拉·球面度/平方米（1 lx = 1 lm/m= 1 cd·sr·m）。

The lux (symbol: lx) is the SI unit of illuminance and luminous emittance, measuring luminous flux per unit area. It is equal to one lumen per square metre. In photometry, this is used as a measure of the intensity, as perceived by the human eye, of light that hits or passes through a surface. It is analogous to the radiometric unit watts per square metre, but with the power at each wavelength weighted according to the luminosity function, a standardized model of human visual brightness pe****tion. In English, "lux" is used in both singular and plural.