temp

| Photometric term | Notation | Unit | | ------------------- | -------- | ----------------------------- | | Luminous power | $\Phi$ | Lumen ($lm$) | | Luminous intensity | $I$ | Candela ($cd$) or $\frac{lm}{sr}$ | | Illuminance | $E$ | Lux ($lx$) or $\frac{lm}{m^2}$ | | Luminance | $L$ | Nit ($nt$) or $\frac{cd}{m^2}$ | | Radiant power | $\Phi_e$ | Watt ($W$) | | Luminous efficacy | $\eta$ | Lumens per watt ($\frac{lm}{W}$) | | Luminous efficiency| $V$ | Percentage ($%$) |