Illumination Conversion Hub

Understanding Illumination & Lux Metrics

Illumination, or illuminance ($E_v$), is the total luminous flux incident on a surface per unit area ($E_v = \frac{d\Phi_v}{dA}$). Measured in Lux ($\text{lx} = 1\text{ lm}/\text{m}^2$) in SI and Foot-candles ($\text{fc} = 1\text{ lm}/\text{ft}^2$) in Imperial ($1\text{ fc} \approx 10.76391\text{ lx}$). Governs architectural lighting codes, office ergonomics, and greenhouse photoperiod sizing.