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arXiv · 2510.19148

Fully automatic fabrication of fibre Bragg gratings using an AI-powered femtosecond laser inscription system

Wenbo Liu·Guiyuan Cao·Zian Liu·Hongyang Chen·Hao Zhang·Renjie Li·Keng-Te Lin·Han Lin·Baohua Jia
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Abstract

Fibre Bragg gratings (FBGs) are widely used in optical sensing and communication systems. Femtosecond laser inscription (FLI) enables hydrogen-free, thermally stable, high-resolution, and complex structures of FBG fabrication, but its practical application is limited by manual operation, low throughput, and sensitivity to laser alignment. In this study, we present an AI-powered FLI system that enables automated, stable, and efficient FBG fabrication. By integrating a Multi-Layer Perceptron (MLP) model for real-time fabrication position correction, the system maintains precise laser alignment (-0.6 to 0.2 microns of the fibre core plane) and ensures consistent processing. Strong and weak FBGs were fabricated in different types of fibres, and their spectral characteristics-including central wavelength, reflectivity, and FWHM-exhibited high stability and repeatability. The results demonstrate that the proposed AI-powered FLI system significantly reduces manual intervention while achieving reliable FBG performance. This approach holds great promise for scalable, high-throughput FBG production and can be extended to the fabrication of arbitrary FBG structures across various fibre types. With further training and model refinement, the AI-powered FLI provides a scalable and intelligent platform for next-generation automated FBG manufacturing.

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Wenbo Liu, Guiyuan Cao, Zian Liu, Hongyang Chen, Hao Zhang, Renjie Li, Keng-Te Lin, Han Lin, Baohua Jia. 2025-10-22. Fully automatic fabrication of fibre Bragg gratings using an AI-powered femtosecond laser inscription system. https://arxiv.org/abs/2510.19148

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