  Using a white light interferometric microscope (WLIM) we measure the
photodamage induced change in the complex index of refraction of disperse
orange 11 (DO11) dye-doped (poly)methyl-methacrylate. We find that the change
in the imaginary part of the refractive index is consistent with previous
measurements of photodamage-induced absorbance change. Additionally, we find
that the change in the real refractive index can be separated into a component
due to damage to the dye molecules and a component due to irreversible damage
to the polymer.
