EPFL researchers have developed an optical fiber capable of detecting what sort of material or liquid they have come into contact with.
Their research has been published in Nature Communications.
In recent years optical fibers have served as sensors to detect changes in temperature, like a thermometer, and pressure, like an artificial nerve. This technique is particularly useful in structures such as bridges and gas pipelines.
EPFL researchers have now come up with a new method that enables optical fibers to identify whether they are in contact with a liquid or a solid. This is achieved by simply generating a sound wave with the help from a light beam within the fiber.
This study was conducted by the Group for Fibre Optics (GFO) run by Luc Thévenaz within the School of Engineering and has been published in Nature Communications.
A sensor that doesn’t disturb the light
No wider than a strand of hair, an optical fiber made of glass transmits light that varies according to four parameters: intensity, phase, polarization and wavelength. These parameters are altered when the fiber is stretched or the temperature changes, enabling the fiber to act like a sensor by detecting cracks in structures or abnormal temperatures. But up to now it was not possible to determine what was happening around the fiber without having light escape the fibre, which disrupts its path.
The method developed at EPFL uses a sound wave generated inside the fiber. It is a hyper-frequency wave that regularly bounces off the fiber’s walls. This echo varies at different locations depending on the material the wave comes into contact with. The echoes leave an imprint on the light that can be read when the beam exits the fiber, making it possible to map out the fiber’s surroundings. This imprint is so faint that it hardly disturbs the light propagating within the fiber. The method could be used to sense what is going on around a fiber and send light-based information at the same time.
The researchers have already immersed their fibers in water and then in alcohol, before leaving them out in the open air. Each time, their system was capable of correctly identifying the change in the surroundings. “Our technique will make it possible to detect water leakages, as well as the density and salinity of fluids that come into contact with the fiber. There are many potential applications,” says Thévenaz.
Spatial and temporal detection
These changes in the surroundings are located thanks to a simple time-based method. “Each wave impulse is generated with a slight time lag. And this delay is reflected upon the beam’s arrival. If there were any disturbances along the way, we can both see what they were and determine their location,” explains Thévenaz. “For the moment, we can locate disturbances to within around ten meters, but we have the technical means to increase our accuracy to one meter.”
The idea of using a sound wave in optical fibers initially came from the team’s partner researchers at Bar-Ilan University in Israel. Joint research projects should follow.
Receive an email update when we add a new OPTICAL FIBER article.
The Latest on: Optical fiber
via Google News
The Latest on: Optical fiber
- Vodafone Italia, Open Fiber launch EUR 12 mln Alessandria FTTH service on December 17, 2018 at 12:35 am
The Open Fiber wholesale-only venture of Italian utility giant Enel and state lender CDP has teamed up with operator partners Vodafone Italia to launch fibre-optic services in the city of Alessandria ... […]
- Fiber Optics Market: Global Industry Analysis, Size, Share, Trends and Forecast 2025 by Suppliers, Key Players and Demand Overview on December 16, 2018 at 9:41 pm
Adroit Market Research studied Global Fiber Optics Market Size by Type (Single mode and Multi-mode), by Material Type (Glass and Plastic), by Vertical (Telecommunication & Broadcasting, Networking inf... […]
- Global Optical Fiber Cables market by types, applications, countries, companies and forecasts to 2023 covered in a latest research on December 14, 2018 at 2:05 pm
This report focuses on the Optical Fiber Cables in Global market, especially in North America, Europe and Asia-Pacific, South America, Middle East and Africa. This report also categorizes the market b... […]
- Global Optical Fiber Preform Manufacturing Equipments Market Insights, Size, Key Players, Regions, Type, Application, Forecast until 2025 on December 14, 2018 at 6:00 am
An up-to-date research report has been disclosed by Market Research Hub highlighting the title “Global Optical Fiber Preform Manufacturing Equipments Market Insights, Forecast to 2025” which provides ... […]
- Rapid Industrialization to Boost Aerospace Fiber Optics Market on December 14, 2018 at 5:30 am
An optical fiber is a transparent fiber made of glass threads with a diameter slightly greater than that of a human hair. These glass threads are capable of transmitting light between the ends of the ... […]
- Global Optical Fiber Preform Manufacturing Equipments examined in new market research report on December 13, 2018 at 4:57 pm
Global Optical Fiber Preform Manufacturing Equipments Market Research Report 2018 contains historic data that spans 2013 to 2017, and then continues to forecast to 2025. That makes this report so inva... […]
- Passive Optical Networking on December 13, 2018 at 8:43 am
I had heard of Passive Optical Networks (PONs) through general articles about how fiber-to-the-home works, but I had to be honest, I had none. I consider myself somewhat network savvy – I have a numbe... […]
- Corning Precision Glass Solutions and WaveOptics Sign Long-Term Supply Agreement for High-Performance Augmented Reality Optics on December 13, 2018 at 6:08 am
Corning`s industry-leading products include damage-resistant cover glass for mobile devices; precision glass for advanced displays; optical fiber, wireless technologies, and connectivity solutions ... […]
- ECI Unveils 1.2T Dual-Channel Optical Blade on December 13, 2018 at 5:34 am
The programmable-adaptive optical network approach enables optimal returns on fiber CapEx investments by maximizing bandwidth capacity from the underlying fiber optic network. It can be applied to upg... […]
via Bing News