Minghong Yang

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Abstract Raman spectroscopy has demonstrated widespread applicability across diverse medical, environmental, and industrial sectors. This paper introduces a Raman spectroscopy fiber-optic sensor based on free-space optical coupling. Its simplified structure and high tolerance to alignment render it highly adaptable to various complex environments, thereby significantly expanding the on-site utility of Raman spectroscopy technology.

A novel, to the best of our knowledge, and compact fiber-optic hydrogen sensor based on light intensity demodulation and controllable optical heating technology is proposed and experimentally investigated. This system employs three photodetectors for optic signal transformation.