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Updated: Jul 7, 2026
08:23
A Random-displacement Measurement by Combining a Magnetic Scale and Two Fiber Bragg Gratings
Published on: September 30, 2019
Fiber-optic strain-displacement sensor employing nonlinear buckling
Applied Optics
|May 1, 1997
Summary
This study introduces novel fiber-optic sensors that measure strain and displacement using controlled fiber buckling and bend loss. These simple, repeatable, and cost-effective sensors offer a wide sensing range and high-temperature operation.
Area of Science:
- Photonics and Materials Science
- Optical Sensing Technologies
Background:
- Traditional strain and displacement sensors often face limitations in range, cost, or high-temperature performance.
- Developing robust and cost-effective sensing solutions is crucial for structural health monitoring.
Purpose of the Study:
- To introduce a new class of intrinsic fiber-optic sensors for strain and displacement measurement.
- To demonstrate a practical implementation using multimode optical fibers and explore high-temperature capabilities.
Main Methods:
- Utilizing the precisely controlled nonlinear buckling of optical fibers.
- Measuring the resulting optical bend loss as a function of fiber displacement.
- Developing a multimode fiber sensor configuration.
Main Results:
- The sensor exhibits a wide sensing range, from sub-nanometer to millimeters.
- A linear response and excellent repeatability were observed over a broad displacement range.
- A high-temperature version demonstrated reliable operation up to 600 degrees C.
Conclusions:
- This new fiber-optic sensor technology offers a simple, cost-effective, and versatile solution for strain and displacement sensing.
- The sensor's performance characteristics make it suitable for diverse structural monitoring applications, including those at elevated temperatures.
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