The research focuses on the development of new high-sensitivity, multifunctional, miniaturized special optical fiber devices, along with their sensing theory and key technologies, addressing the challenges of detecting difficult-to-measure parameters in special and complex environmental conditions. The research results have wide applications in fields such as petrochemicals, marine exploration, electricity, mining, railways, intelligent transportation, and military defense, with an emphasis on improving the sensitivity, stability, anti-interference ability, and miniaturization of optical fiber sensors to meet the high-precision real-time monitoring and reliability needs of various industries.