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Laser-Induced Damage in Optical Materials
Generally speaking, the principle of a destructive measurement consists of perform-
ing local or total wear on the part to open up or reveal the microcracks, the depth of
which can then be measured. Dierent types of wear methods have been studied. For
example, Carr soaks the parts in successive HF baths and used a microscope observa-
tion to measure SSD (Carr etal. 1999). Other methods are polishing a taper (Hed etal.
1989) or a ball dimple (Zhou etal. 1994) in the part to be qualied using a suitable tool.
If the shape of the local wear produced is known, it is possible to determine the SSD
depth ...