An apparatus for measuring the reflectance properties of an object having
a front reflecting surface and at least one back reflecting surface. The
apparatus includes a sample stage for placement of the object, a light
source, a detector configured to detect reflected light from the object,
and a positioning device configured to provide a plurality of angular
positions for the light source and the detector relative to the object on
the sample stage such that incident light on the object is specularly
reflected towards the detector and the reflected light received at the
detector includes a front surface reflection from the object and at least
one back surface reflection from the object. The method includes
illuminating the object at varying angles of incidence, collecting
reflected light from the front and back reflecting surfaces of the object
at respective specularly reflected angles, wavelength resolving the
reflected light into a color spectrum, and analyzing an intensity of the
color spectrum as a function of wavelength.