Abstract

The proper function of protective coating layers is essential for the handling and application of brittle optical fibers. The elastic parameters of polymer coatings can be studied through off-line analysis of test samples. However, the monitoring of these properties on a working fiber during service is challenging. In this work, we use forward stimulated Brillouin scattering processes in standard single mode fibers to measure the acoustic velocity in several types of coating layers. Pump light launches short acoustic pulses outward from the core of the fiber. Multiple reflections at the boundaries between cladding and coating, and between coating and air, form a series of delayed acoustic echoes across the core. These echoes are monitored, in turn, by photo-elastic phase modulation of probe light. Data are collected at temperatures between 25–120 °C. The thermal dependence of the acoustic velocities in several coatings and of the F-SBS resonance frequencies is investigated. Observations are corroborated by calculations. The proposed technique is well suited for research and development of coating materials, production line quality control, reliability studies and preventive maintenance of working fibers.

Forward stimulated Brillouin scattering in optical nanofibers

Min Cao, Haisu Li, Min Tang, Yuean Mi, Lin Huang, and Guobin Ren
J. Opt. Soc. Am. B 36(8) 2079-2086 (2019)

Stimulated Brillouin scattering in optical fibers

Andrey Kobyakov, Michael Sauer, and Dipak Chowdhury
Adv. Opt. Photon. 2(1) 1-59 (2010)

Measuring glass transition of a polymer coating layer over working fiber using forward Brillouin scattering

Alon Bernstein, Elad Zehavi, Yosef London, Mirit Hen, Andrei A. Stolov, and Avi Zadok
Opt. Lett. 48(19) 5037-5040 (2023)

Optomechanical sensing of liquids outside standard fibers using forward stimulated Brillouin scattering

Yair Antman, Alex Clain, Yosef London, and Avi Zadok
Optica 3(5) 510-516 (2016)

Analysis of acousto-optic interaction based on forward stimulated Brillouin scattering in hybrid phononic-photonic waveguides

Ruiwen Zhang, Guodong Chen, and Junqiang Sun
Opt. Express 24(12) 13051-13059 (2016)