I present angle-dependent directional hemispherical reflectance (DHR) and bidirectional reflectance distribution function (BRDF) measurements of three highly absorbing black appliqués in the 250–2000-nm broadband spectral region. DHR measurements of Energy Science Laboratories, Inc. (ESLI), Rippey, and Rodel appliqués were obtained at incidence angles of 8°, 50°, and 70°. For an incidence angle of 8°, the ESLI appliqué exhibited the lowest DHR value of 0.3% across this entire spectral region, whereas the Rippey and Rodel had DHR values of 1.5% and 2.0–2.5%, respectively. In-plane BRDF measurements of the appliqués, obtained at a wavelength of 633 nm and incidence angle of 10°, yielded Lambertian profiles from −80° to +80° with values ranging from ~10<sup>−3</sup> sr<sup>−1</sup> for the ESLI, 6 × 10<sup>−3</sup> sr<sup>−1</sup> for the Rippey, and 9 × 10<sup>−3</sup> sr<sup>−1</sup> for the Rodel appliqué. In addition, rms surface roughness and correlation lengths for the Rippey and the Rodel appliqués were determined. The in-plane BRDF data were used to estimate the reflected specular component from Beckmann’s scattering theory, and excellent agreement was found.
© 2001 Optical Society of America
(120.5700) Instrumentation, measurement, and metrology : Reflection
(120.5820) Instrumentation, measurement, and metrology : Scattering measurements
(160.4670) Materials : Optical materials
(160.4760) Materials : Optical properties
(290.5880) Scattering : Scattering, rough surfaces
Steven R. Meier, "Reflectance and Scattering Properties of Highly Absorbing Black Appliqués Over a Broadband Spectral Region," Appl. Opt. 40, 6260-6264 (2001)