摘要 |
A fluorite having all the more excellent laser durability compared to a conventional fluorite is provided. A fluorite is proposed, in which the standard deviation of the surface areas of the Voronoi regions in a diagram from a Voronoi decomposition of the distribution of etch-pits in the (111) plane is 6,000 µm 2 or less, or, in which the standard deviation of the distances of the Delaunay edges in a diagram from a Delaunay decomposition of the distribution of etch-pits of the (111) plane is 80 µm or less. |