Scientists have developed a novel method to significantly improve the spatial resolution of distributed temperature sensing using plastic optical fibers (POFs). Their approach enables precise detection of temperature variations over short distances, achieving a theoretical spatial resolution of approximately 4.8 centimeters.
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The research, published in Optical Fiber Technology on January 27th, 2025, tackles a key limitation in fiber-optic sensing.
Our work addresses a critical challenge in distributed fiber-optic sensing by pushing the boundaries of spatial resolution. By optimizing the modulation amplitude and fiber length, we have unlocked new possibilities for high-resolution temperature sensing, which could have important applications in fields such as structural health monitoring and industrial process control.
Yosuke Mizuno, Professor, Yokohama National University
Distributed optical fiber sensors, particularly those based on Brillouin scattering, are widely used to measure strain and temperature changes along optical fibers. However, achieving high spatial resolution has traditionally been hindered by noise interference and the physical properties of sensing fibers. To overcome these limitations, the research team utilized perfluorinated graded-index POFs, which offer high-temperature sensitivity and low strain sensitivity—making them ideal for precise temperature measurements.
By reducing the fiber length relative to the measurement range, the researchers effectively suppressed noise and increased modulation amplitude, leading to improved spatial resolution. This approach allowed them to accurately detect a 7.0-centimeter cooled section, demonstrating its effectiveness in monitoring localized temperature changes in practical applications.
Their findings are helping to lay the foundation for further advancements in distributed sensing technologies. The next steps include extending the sensing length while maintaining high spatial resolution and adapting this technique to measure additional physical parameters such as pressure and humidity. The team also aims to refine the system for real-world applications, including infrastructure monitoring and industrial diagnostics.
This breakthrough represents a major advance in fiber-optic sensing technology. We are excited to continue refining this approach and exploring its potential to address real-world challenges.
Yosuke Mizuno, Professor, Yokohama National University
Journal Reference:
Ochi, S., et al. (2025) High-resolution distributed temperature sensing along polymer optical fiber using Brillouin optical correlation-domain reflectometry. Optical Fiber Technology. doi.org/10.1016/j.yofte.2025.104144