The lux (symbol: lx) is the SI derived 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.
Accordingly, what is the measurement of light intensity?
One candela per steradian is termed a lumen, which is the measure of light intensity people are most familiar with. However, what matters most in terms of measuring light intensity is the number of lumens falling on a surface, which is expressed as lux.
What unit indicates light intensity?
In physics, intensity is the power transferred per unit area, where the area is measured on the plane perpendicular to the direction of propagation of the energy. In the SI system, it has units watts per square metre (W/m2).
What is a unit of measurement for light?
- Candela (cd) Unit of luminous intensity of a light source in a specific direction. Also called candle.
- Footcandle (fc or ftc) Unit of light intensity, measured in lumens per square foot.
- Lumen (lm) Unit of light flow or luminous flux.
- Lux (lx) Unit of illumination equal to one lumen per square metre.