1270nm to 1610nm or 1550nm Fiber Bragg Grating FBGs are a kind of diffraction grating formed by periodically modulating the refractive index of the core of the fiber through a certain method. It is a passive filter device. Grating fibers are widely used in the fields of optical fiber communication, optical fiber sensing and optical fiber signal processing because of their small size, low fusion loss, full compatibility with optical fibers and embedded intelligent materials, and their resonant wavelength is sensitive to the changes of temperature, strain, refractive index, concentration and other external environment.
