Fig. 6

Level of light reflected from a perfectly Lambertian surface Pr per unit solid angle Ω (as dPr/dΩ) as a function of collection angle θ, for an incident beam of power 1 mW.
Level of light reflected from a perfectly Lambertian surface Pr per unit solid angle Ω (as dPr/dΩ) as a function of collection angle θ, for an incident beam of power 1 mW.