Light-based technologies, from global internet infrastructure to advanced medical sensors, are fundamental to modern life. Many of these systems rely on micro/nanoscale optical fibers (MNFs)—filaments so thin they can be narrower than a wavelength of light. Beyond lab experiments, these fibers are pivotal for high-performance sensors and hold immense promise for future wearable health monitors, environmental detectors, and ultra-compact optical chips for faster data processing. They are also key building blocks for cutting-edge quantum communication and ultra-sensitive imaging technologies.
A major barrier to their widespread adoption has been the extreme difficulty of manufacturing them perfectly. Their performance is exquisitely sensitive to shape, where a deviation of just a few nanometers can render them useless. Traditionally, measuring and controlling their form during production has been a significant challenge.
Now, a team led by Professor Yaoguang Ma at Zhejiang University has developed an elegant solution. Their novel technique uses the light already traveling within the fiber as a probe. As the fiber is drawn, different light modes interact and create evolving interference patterns. The researchers realized these patterns act as a recorded history of the fiber’s formation, much like the annual rings in a tree trunk encode its growth.
By applying artificial intelligence to decode these “optical growth rings” in real time, the system can not only determine the fiber’s diameter but also reconstruct its full three-dimensional shape along its entire length. This process achieves an exceptional precision with an error below 0.35% and takes only seconds. Moreover, the system incorporates a real-time feedback loop, allowing it to actively guide and correct the fabrication process as it happens, ensuring each fiber is made exactly to specification.
This work, titled “Nanoprecision real-time diameter control of micro/nanofibers via higher-order mode interference”, published in Frontiers of Optoelectronics (published on Apr. 21, 2026, DOI:10.2738/foe.2026.0022), paves the way for smart, precise manufacturing of optical fibers. This capability is vital for realizing reliable and advanced photonic technologies that will power future innovations in computing, healthcare, and communications.
DOI：10.2738/foe.2026.0022