The lux (symbol: lx) is the SI derived unit of illuminance, 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 watt per square metre, but with the power at each wavelength weighted according to the luminosity function, a standardized model of human visual brightness perception
| Standard Units | |
|---|---|
| Footcandle | {{footcandle}} |
| Kilolux | {{kilolux}} |
| Lumen/square centimeter | {{lumenpersquarecentimeter}} |
| Lumen/square foot | {{lumenpersquarefoot}} |
| Lumen/square inch | {{lumenpersquareinch}} |
| Lumen/square meter | {{lumenpersquaremeter}} |
| Metercandle | {{metercandle}} |
| Milliphot | {{milliphot}} |
| Nox | {{nox}} |
| Phot | {{phot}} |