Fiber Bragg Grating

Fiber Bragg Grating (FBG) is a passive filter formed by axially and periodically modulating the refractive index of the fiber core to create a diffraction grating. Thanks to its compact size, low splice loss, full fiber compatibility, and ability to be embedded in smart materials, and because its resonant wavelength is highly sensitive to temperature, strain, refractive index, and concentration, FBGs are widely used in fiber lasers, fiber communications and sensing, optical filters, and FBG WDM modules.

We employ ultrafast femtosecond laser direct-write technology, using the laser’s high peak power and nonlinear effects to write FBGs without stripping the coating. The beam passes through the coating into the core, inscribing gratings at precise intervals. Compared to traditional methods, this process requires no hydrogen loading or photosensitization, preserves fiber strength, and produces gratings with a more stable, precise spectrum that withstands high temperatures and harsh environments.

This technology also supports multiple gratings on a single fiber—with no splices and no coating removal—offering excellent tensile strength. Each grating’s parameters can be customized and the spacing precisely controlled, enhancing system stability and reliability in fiber sensing and communications.

Technical Specifications: