We demonstrate the fabrication of the fiber Bragg grating (FBG) in a self-developed Yb-doped seven-core fiber using two femtosecond laser direct writing methods: a grating array inscription method and a plane-by-plane inscription method. The array fabrication method uses the femtosecond laser to. Fiber Bragg Gratings (FBGs) are essential components in fiber-optic sensing systems owing to their high sensitivity, compact structure, and immunity to electromagnetic interference, and have been widely applied in structural health monitoring, aerospace, energy, and biomedical fields. However, conventional UV-induced FBGs cannot survive at temperatures above 300 °C and are unable to achieve SHM in extreme environments. A femtosecond (fs) laser, featuring ultra-short. There are actually three established methods available to manufacture a Fiber Bragg Grating. The laser is focused into the core of the fiber and.
