Automated Fabrication of Active Optical Fiber Sensors
This invention is an automated system and method for fabricating active optical fiber sensors using a direct laser-writing approach. This new process drastically improves the manufacturability and multiplexability of these sensors, expanding their applicability and commercial potential
Description
The disclosed technology provides a new, automated approach to fabricating active optical fiber sensors that can be easily multiplexed on a single fiber. The method uses a direct-writing approach with an ultrafast laser system, such as a femtosecond ultrafast laser, to inscribe nanograting structures directly into the core of an optical fiber. These nanogratings serve as scattering points or "optical taps" that scatter light out of the fiber core. An energy transducing element is then formed on the fiber's outer surface to absorb the scattered light and convert it into another energy form, like heat or electricity, which can be used to tune in-fiber components. The process is performed using a reel-to-reel setup, which allows for continuous, automated manufacturing without the need to strip the fiber's polymer coating. This approach can produce various sensor types, including intrinsic Fabry-Perot interferometers (IFPIs) or fiber Bragg gratings (FBGs), in a single, automated process, eliminating manual steps.Applications
- Extreme Environment Sensing: Measuring physical and chemical parameters in harsh conditions.- Flow and Level Sensing
- Chemical Sensing
- Distributed Sensing Networks: Creating highly multiplexed sensor arrays for large-scale monitoring applications.
- Defense and Energy
Advantages
- Enhanced Manufacturability: The fully automated, direct laser-writing approach simplifies the fabrication process, eliminating complex, manual steps like stripping, cleaving, and splicing.- Improved Multiplexability: The continuous, reel-to-reel fabrication allows for the creation of multiple sensors on a single fiber, overcoming a key limitation of prior methods.
- Active Sensing Capabilities: The sensors are directly powered by in-fiber light, enabling them to actively adapt to changing environments and perform multi-parameter measurements.
- High Spatial Resolution: The ability to perform high-resolution measurements of physical and chemical parameters in extreme environments, which is often unattainable with passive sensors.
- Durability and Stability: The laser-induced nanogratings are based on type-II laser-material interaction, known for exceptional stability under high temperatures.