Directional–hemispherical reflectance for Spectralon by integration of its bidirectional reflectance

Abstract

The directional-hemispherical reflectance is obtained for Spectralon, the material chosen for onboard radiometric calibration of the multiangle imaging spectroradiometer, at laser wavelengths of 442, 632.8, and 859.9 nm. With p- and s-polarized incident light and for an angle of incidence of 45 degrees , the bidirectional reflectance distribution function was measured over a polar angle range of 1-85 degrees and a range of azimuthal angles of 0-180 degrees in 10 degrees increments. The resultant directional-hemispherical reflectance is found by integration to be 1.00 ? 0.01 at 442 nm, 0.953 ? 0.01 at 632.8 nm, and 0.956 ? 0.01 at 859.9 nm. The experimental methodology and the data analysis are presented together with a full discussion of the primary experimental errors.