During polishing of optical surfaces, light scattering from within the sample under test enables on machine monitoring of surface roughness levels during polishing. Surface roughness levels of 0.6 nm rms have been detected and the influence of different pH values of polishing slurries on the surface quality being generated have been monitored. In addition, iIRM’s capability to function as in process contamination control of industrial polishing processes has been demonstrated.
O. Faehnle, O. Faehnle,
"In process monitoring of optics fabrication", Proc. SPIE 10326, Fourth European Seminar on Precision Optics Manufacturing, 103260Y (15 June 2017); doi: 10.1117/12.2277192; https://doi.org/10.1117/12.2277192