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08:32
Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors
Published on: January 29, 2013
Spatially weighted, grating-based, two-mode, elliptical-core optical fiber vibration sensors
Optics Letters
|September 29, 2009
Summary
This study introduces chirped fiber gratings in elliptical-core optical fibers as spatially weighted sensors for vibration analysis. The method enhances detection of cantilever beam vibration modes, achieving significant mode suppression.
Area of Science:
- Photonics
- Fiber Optics
- Sensor Technology
Background:
- Photoinduced refractive-index changes in optical fibers impact beat length and sensor sensitivity.
- Chirped gratings are fabricated by attaching fibers to strained cantilever beams.
Purpose of the Study:
- To utilize in-line chirped gratings shaped to vibration modes as spatially weighted fiber sensors.
- To demonstrate enhanced vibration analysis of cantilever beams.
Main Methods:
- Writing chirped gratings onto elliptical-core optical fibers.
- Attaching these fibers to cantilever beams in a strained state.
- Shaping the grating chirp to match vibration mode shapes.
Main Results:
- Demonstrated enhanced detection of the first and second vibration modes of a cantilever beam.
- Achieved vibration mode suppression of approximately 10 dB.
Conclusions:
- Spatially weighted fiber sensors with in-line chirped gratings are effective for vibration analysis.
- This technique improves the detection sensitivity for specific vibration modes.
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