At the Third National Photonics Technology Forum held in Guangzhou from March 31st to April 3rd, 2023, Professor Wang Yiping's team from Shenzhen University and Shenzhen Photon Sensing Technology Co., Ltd. unveiled for the first time in China a large-scale fiber Bragg grating array femtosecond laser fully automatic fabrication technology, equipment, and array products.

The technology achieves efficient fully automatic fabrication of kilometer-scale, reel-to-reel, large-scale serial/parallel integrated fiber Bragg grating arrays (including weak reflection points) in single-core and multi-core fibers. It boasts advantages such as direct writing with coating, no need for masking templates, no need for hydrogen loading, no need for secondary coating, and realizes fully automated program control of fiber movement, clamping, feeding, winding, fiber core alignment, laser focusing, exposure, and other grating preparation processes. The fabricated fiber Bragg grating arrays retain the original tensile strength, high-temperature resistance, and long-term stability of the fibers.

The on-site unveiled large-scale identically weakly reflective fiber Bragg grating array has a grating wavelength of 1550 nm, with a minimum grating length of less than 0.5 mm, a minimum grating spacing of less than 0.5 mm, a minimum reflectivity of less than one hundred thousandth, over 10,000 grating units, and an extinction ratio of 15 dB.

The parameters such as grating wavelength, grating reflectivity, grating spacing, and grating quantity can be customized based on user requirements. This large-scale fiber Bragg grating array holds broad prospects for applications in distributed fiber sensing fields such as oil well exploration, perimeter security, bridges, dams, aerospace, and aviation. It has the potential to significantly enhance key metrics such as measurement precision, measurement distance, and spatial resolution for distributed fiber sensing technologies like DAS, DTS, OFDR, thus acting as a booster for distributed fiber sensing technology.