Epner

Two different instruments were used to measure the reflectance.  One to scan from 200nm to 2,500nm.  Both sides were measured and showed little difference.  The reflectance to approximately 700 nm is really low, below 1%.  Then as you see it rises to approximately 4% at 900 to 1,000 nm or so and decreases.  The other curves, there are three, are all the same but displayed with differing expansion on the reflectance axis.  These curves run from 2.5 microns to 20 microns.

Measurements were provided by the National Institute of Standards and Technology (NIST) and made using a spectrometer coupled to an integrating sphere to enable total and diffuse reflectance measurements.  In the "total" measurement the specular reflectance is included.  In the "diffuse" measurement the specular beam is excluded, since the geometry is made that the specular reflection from the sample passes out of the integrating sphere through a port. 

Measurements were provided by the National Institute of Standards and Technology (NIST) and made using a spectrometer coupled to an integrating sphere to enable total and diffuse reflectance measurements.  In the "total" measurement the specular reflectance is included.  In the "diffuse" measurement the specular beam is excluded, since the geometry is made that the specular reflection from the sample passes out of the integrating sphere through a port.