A Recommendation Inspection to Control Sub-Surface Damage in Sapphire

摘要

We will recommend an inspection practice for single-crystal optics, we do this with a hope: that it is a good start on developing a generally useful sub surface damage inspection standard serviceable for all single crystal based optics. The approach, which is now well demonstrated as effective for sapphire, requires test pieces successfully progress through four separate inspection steps. Passage from one step to the next is conditional on passing the current one. Failure at any step requires rejection and return for reworking. These steps range from using shop floor practices - a careful visual inspection - onto use of X-ray topography, an advanced diagnostic. The possibility to rework inspected parts is the key argument for just inspecting, over using proof testing. Preferably, both are and would be used as complementary methods.