Here’s a short informational piece prepared on — suitable for a glossary, safety bulletin, or technical brief. Opticut Crack Definition An Opticut crack refers to a specific type of brittle fracture or surface split that occurs in materials (commonly ceramics, glass, coated optics, or hardened steels) after an optical-quality cutting process — such as laser cutting, diamond scribing, or waterjet guided laser cutting. The term combines “optic” (relating to precision or visual inspection) and “cut” (the separation method), with “crack” denoting an unintended failure along or near the cut edge.