Measurement of a bidirectional reflectance distribution and system achievement based on a hemi-parabolic mirror

A novel approach is proposed for measuring a surface's bidirectional reflectance distribution function rapidly and accurately. By using a hemi-parabolic mirror, the angular distribution of a surface's reflectance in threedimensional space can be transformed into a two-dimensional planar image, which is collected by a CCD camera and goes through a followed coordinate mapping. It is shown that, using this method and apparatus, measurement of in plane and out of plane reflectance distributions may be realized within two minutes.