Scientists enhance high-resolution distributed temperature sensing using plastic optical fibers

Scientists have developed a new approach to significantly enhance the spatial resolution of distributed temperature sensing using plastic optical fibers (POFs). Their work demonstrates the successful detection of temperature changes over short distances, achieving a theoretical spatial resolution of approximately 4.8 centimeters.

Their research is published in Optical Fiber Technology.

“Our work addresses a critical challenge in distributed fiber-optic sensing by pushing the boundaries of spatial resolution,” said Professor Yosuke Mizuno of Yokohama National University.

“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.”

Distributed optical fiber sensors based on Brillouin scattering are widely used to measure strain and temperature changes along optical fibers. However, achieving high spatial resolution has traditionally been limited by noise interference and the physical properties of the sensing fibers. The team’s new approach uses perfluorinated graded-index POFs, which have unique properties, including high temperature sensitivity and low strain sensitivity, making them ideal for precise temperature measurements.

The researchers showed that by reducing the fiber length relative to the measurement range, they could suppress noise and increase the modulation amplitude, improving spatial resolution. This method allowed them to detect a 7.0-centimeter cooled section with high accuracy, demonstrating the potential for monitoring localized temperature changes in real-world applications.

The team’s findings open new possibilities for advancements in distributed sensing technologies. Future work will explore extending the sensing length while maintaining high spatial resolution, as well as applying this technique to measure other physical parameters such as pressure and humidity. The researchers also aim to refine the system for practical use in critical applications, including infrastructure monitoring and industrial diagnostics.

“This breakthrough represents a major advance in fiber-optic sensing technology,” said Professor Mizuno. “We are excited to continue refining this approach and exploring its potential to address real-world challenges.”

The research team includes Seiga Ochi and Yosuke Mizuno from the Faculty of Engineering, Yokohama National University, and Keita Kikuchi, Shuto Tsurugai, and Heeyoung Lee from the Graduate School of Engineering and Science, Shibaura Institute of Technology.