Self written waveguide interfaced with hollow core fiber for simultaneous temperature and humidity detection

Abstract

The interfacing of optical fibers with materials can lead to greater versatility for measurand detection. In this work, we spliced a single mode fiber to a section of a hollow core fiber. In this structure, a self-written waveguide was fabricated at the hollow core fiber tip using a UV curable polymer, resulting in multiple Fabry-Perot interferometers in a reflection scheme. With the Fourier band-pass method, each interferometer was independently analyzed, and different sensitivities were attained for each interferometer to temperature and humidity, potentiating its simultaneous detection with high sensitivity, resolution and quick response time.