Improvement in polishing of fused-silica parts

High-power laser optics can require high-quality polished surfaces for damage resistance. Fabrication efficiency for producing quality surfaces becomes an important cost consideration. Our systematic study of fused-silica polishing conditions has led to the discovery that enhanced removal efficiency and higher quality optical surfaces can be achieved by decreasing the cerium oxide polishing slurry pH to 4. Both hydrochloric acid and citric acid have been used to lower the slurry pH with equal success.