A Micro Bubble Structure Based Fabry-Perot Optical Fiber Strain Sensor with High Sensitivity and Low-Cost...

Area of Science:

• Optoelectronics
• Fiber optics sensors
• Materials science

Background:

• Strain sensors are crucial for monitoring structural integrity and physical changes.
• Existing sensors often face limitations in sensitivity, cost, or fabrication complexity.
• Optical fiber sensors offer advantages like immunity to electromagnetic interference and remote sensing capabilities.

Purpose of the Study:

• To propose and demonstrate a novel high-sensitivity, low-cost strain sensor.
• To develop a strain sensor utilizing an ultrathin, hollow fiber micro bubble structure.
• To investigate the performance of a Fabry-Perot interferometer (FPI) based sensor with this micro bubble.

Main Methods:

• Fabrication of a micro bubble at the tip of a single-mode fiber (SMF) by splicing a glass tube and expanding it with gas.
• Integration of the micro bubble structure into a Fabry-Perot interferometer (FPI) system.
• Experimental measurement of strain sensitivity using the fabricated sensor.

Main Results:

• Successful fabrication of an ultrathin, hollow fiber micro bubble structure.
• The developed strain sensor achieved a high sensitivity of 8.14 pm/μϵ.
• The sensor demonstrated potential for precise strain measurement with a cavity length of ~155 μm and bubble wall thickness of ~6 μm.

Conclusions:

• The proposed hollow fiber micro bubble structure is a viable platform for developing high-sensitivity strain sensors.
• This low-cost, FPI-based sensor offers a promising alternative to conventional strain measurement techniques.
• Further research can explore optimizing the micro bubble design for enhanced performance and broader applications.