•Radiant power P
–Rate
at which light energy is transmitted
–Dimension:
power = energy / time
•Flux density F
–Radiant
power per unit area of the surface
–Dimension:
power / area
•Irradiance E: incident flux density of surface
•Radiosity B: exitant flux density of surface
–Dimension:
power / area
•Flux density at a point F(x) = dP/dx