Subsurface Damage in Optical Materials: Origin, Measurement and Removal

The detection, measurement and removal of subsurface damage is a major effort of the LLNL Optical Sciences and Engineering Group. We will describe and show examples of three methods we are currently using to detect and measure the depth of damage in glasses and crystalline materials: taper polishing and etching, constancy of chemical etch rate, and small specimen fracture. In addition, results will be given to show that the depth of damage can often be approximated from the surface roughness and Young's modulus.