Frequently Asked Questions

These gratings are written into pure-silica-core fiber using femtosecond-laser inscription directly through the fiber's protective coating, without needing to strip or recoat it. Pure-silica-core fiber resists radiation-induced darkening far better than germanium-doped-core fiber.

They're intended for nuclear energy facilities, aerospace applications, and other high-radiation environments where standard Ge-doped-core FBGs would degrade.

Both use femtosecond through-coating inscription; this series is specifically built on radiation-resistant pure-silica-core fiber, making radiation hardness the primary design goal rather than mechanical strength alone. See also our Femtosecond FBG page for the general through-coating writing process.