Distributed Static and Dynamic Strain Measurements in Polymer Optical Fibers by Rayleigh Scattering

Area of Science:

• Optoelectronics
• Fiber optic sensing
• Materials science

Background:

• Distributed strain sensing traditionally relies on specialized, often expensive, optical fibers.
• Existing methods may have limitations in cost-effectiveness or multiparameter measurement capabilities.

Purpose of the Study:

• To demonstrate the efficacy of graded-index perfluorinated optical fiber (GI-POF) for distributed static and dynamic strain measurements.
• To explore the use of Rayleigh scattering with an amplitude-based phase-sensitive Optical Time-Domain Reflectometry (ϕ-OTDR) configuration at 850 nm.
• To assess the potential of polymer optical fibers for cost-effective multiparameter sensing.

Main Methods:

• Utilized a GI-POF for strain sensing.
• Employed an amplitude-based phase-sensitive ϕ-OTDR system operating at 850 nm.
• Exploited changes in Rayleigh backscatter coefficient and intensity for static and dynamic strain detection, respectively.

Main Results:

• Achieved distributed static strain measurements with 4 m spatial resolution up to 3.5% strain by monitoring Rayleigh backscatter coefficient increase.
• Demonstrated vibration/acoustic measurements with sampling frequencies up to 833 Hz by analyzing Rayleigh intensity fluctuations.
• Validated the use of polymer optical fibers for simultaneous static and dynamic strain sensing.

Conclusions:

• GI-POF is a viable and cost-effective material for distributed multiparameter sensing.
• The demonstrated ϕ-OTDR technique at 850 nm offers a versatile approach for strain monitoring.
• Polymer optical fibers present a promising alternative for advanced sensing applications.