Irradiance of the surface area for every unit frequency or wavelength. The phrases spectral flux density or more confusingly "spectral intensity" can also be applied. Non-SI units of spectral irradiance incorporate Jansky = 10 W⋅m⋅Hz and solar flux device (1SFU = ten W⋅m⋅Hz).of new info are apparent in this technique. of these shed a imm