Candela
= Candela
{title2=$\mathrm{cd}=\mathrm{lm\,sr^{-1}}$}
{wiki}
At exactly $540\,\mathrm{THz}$, <radiant intensity> $1/683\,\mathrm{W\,sr^{-1}}$ corresponds to <luminous intensity> $1\,\mathrm{cd}$. This convention specifies a direction, rather than the source's total <luminous flux>. <SI base unit: candela (cd)>{ref}