Luminous Intensity Conversion Hub

Understanding Luminous Intensity & Candela Standards

Luminous intensity ($I_v$) measures perceived optical power emitted by a light source in a particular direction per unit solid angle ($I_v = \frac{d\Phi_v}{d\Omega}$). Measured in Candelas ($\text{cd}$), one of the seven base SI units, weighted by the human eye's spectral sensitivity function $V(\lambda)$. Historically measured in standard candlepower ($1\text{ CP} \approx 0.981\text{ cd}$).