FBG-Assisted Micro-Channel for Refractive Index Measurements

An optical fiber micro-channel sensor assisted by Bragg gratings is presented in this study. The micro-channel was fabricated by femtosecond laser micromachining. The sensor is based on intensity demodulation with compensation for fluctuations and is characterized by blends of different refractive indices infused into the micro-channel. The reflected signal of the sensor grating discloses a linear increase related to the refractive index of the sample. The average sensitivity obtained was (92 ± 2) dBm/RIU.