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Ultra-high sensitivity strain sensor based on biconical fiber with a bulge air-bubble
Optics Letters
|April 15, 2021
Summary
A novel Fabry-Perot interferometer (FPI) strain sensor achieves ultra-high sensitivity using a biconical fiber with an air-bubble. This breakthrough offers the highest reported strain sensitivity for direct wavelength interrogation sensors.
Area of Science:
- Fiber optic sensing
- Optical instrumentation
- Materials science
Background:
- Strain sensors are crucial for structural health monitoring.
- Existing sensors often lack the required sensitivity or are complex.
- Fabry-Perot interferometers offer potential for high-performance sensing.
Purpose of the Study:
- To propose and demonstrate an ultra-high sensitivity Fabry-Perot interferometer (FPI) strain sensor.
- To investigate the sensor's performance in terms of strain and temperature sensitivity.
- To establish a new benchmark for direct wavelength interrogation-based strain sensors.
Main Methods:
- Fabrication of a biconical fiber with a bulge air-bubble at its waist.
- Experimental setup for strain and temperature loading.
- Wavelength interrogation for measuring sensor response.
Main Results:
- Achieved an ultra-high strain sensitivity of 101.7 pm/µɛ.
- Demonstrated the highest strain sensitivity among reported direct wavelength interrogation sensors.
- Exhibited a low temperature sensitivity of approximately 1 pm/°C, resulting in low temperature cross-sensitivity (< 10 nɛ/°C).
Conclusions:
- The proposed FPI strain sensor offers unprecedented sensitivity.
- The unique fiber structure enhances stress concentration for improved deformation.
- This sensor represents a significant advancement for precise strain measurement applications.
