Illuminance

Illuminance is the measure of light intensity on a surface or area. It is typically measured in lux, which is equal to one lumen per square meter. Illuminance can be described as the amount of light that falls on a surface and is usually referred to as brightness, though it should not be confused with luminance, which is how bright a source appears when compared to its surroundings. Illumination levels affect mood and productivity and should be carefully considered when designing lighting schemes in any space.