Editing Transmittance (section)

===Spectral hemispherical transmittance===
'''Spectral hemispherical transmittance in frequency''' and '''spectral hemispherical transmittance in wavelength''' of a surface, denoted ''T''<sub>ν</sub> and ''T''<sub>λ</sub> respectively, are defined as<ref name="ISO_9288-1989" />
:<math>T_\nu = \frac{\Phi_{\mathrm{e},\nu}^\mathrm{t}}{\Phi_{\mathrm{e},\nu}^\mathrm{i}},</math>
:<math>T_\lambda = \frac{\Phi_{\mathrm{e},\lambda}^\mathrm{t}}{\Phi_{\mathrm{e},\lambda}^\mathrm{i}},</math>
where
*Φ<sub>e,ν</sub><sup>t</sup> is the [[Radiant flux|spectral radiant flux in frequency]] ''transmitted'' by that surface into the hemisphere on the opposite side from the incident radiation;
*Φ<sub>e,ν</sub><sup>i</sup> is the spectral radiant flux in frequency received by that surface;
*Φ<sub>e,λ</sub><sup>t</sup> is the [[Radiant flux|spectral radiant flux in wavelength]] ''transmitted'' by that surface into the hemisphere on the opposite side from the incident radiation;
*Φ<sub>e,λ</sub><sup>i</sup> is the spectral radiant flux in wavelength received by that surface.