Fig. 2

Leaf model to measure reflectance over a white background: the reflectance and transmittance values of each layer are indicated.\(R_{surf}\) is the surface reflectivity for both upper and lower leaf surfaces (independent of wavelength), \(R_{leaf} \left( \lambda \right)\) and \(T_{leaf} \left( \lambda \right)\) are the leaf reflectance and transmittance simulated by PROSPECT, assuming no reflectivity at the top and the bottom of the leaf volume. \(R_{wb}\) is the reflectance of the Teflon white background. All the reflectance and transmittance terms are bi-hemispherical except the upper and lower leaf surface reflectivity is directional-hemispherical