title: Reflectance of pigmented polymer coatings: comparisons between measurements and radiative transfer calculations.
abstract: Solar reflectance spectra of pigmented coatings have been obtained from spectroscopic measurements involving integrating sphere attachments. We demonstrate that measured and computed reflectances of an extended four-flux model [Appl. Opt. 37, 2615 (1998)] whose average path-length parameters (APP's) and forward-scattering ratios (FSR's) are explicitly evaluated from a multiple-scattering approach at the front or back interface of the particulate coatings display fairly good agreement. The agreement of these properties in a standard four-flux model [Appl. Opt. 23, 3353 (1984)], which neglects the spectral dependence of the APP and FSR, is found in the near infrared. Good agreement between these two four-flux approaches over the solar spectral range is obtained when the mean values of the APP's and FSR's are used in the standard model.
authors: W E
authors: WE
authors: Vargas
authors: G A
authors: GA
authors: Niklasson