Static FBG strain sensor with high resolution and large dynamic range by dual-comb spectroscopy.

Area of Science:

• Photonics
• Optical Sensing
• Materials Science

Background:

• Fiber Bragg gratings (FBGs) are widely used for strain sensing.
• Conventional FBG sensors often rely on continuous-wave lasers, limiting their scanning speed and range.
• Improving the sensitivity, dynamic range, and multiplexing capability of FBG strain sensors is an ongoing challenge.

Purpose of the Study:

• To demonstrate a novel fiber Bragg grating (FBG) strain sensor utilizing optical frequency combs.
• To employ dual-comb spectroscopy for precise characterization of FBG optical response under strain.
• To enhance the performance metrics of FBG strain sensing.

Main Methods:

• Implementation of a fiber Bragg grating (FBG) sensor system.
• Application of dual-comb spectroscopy for high-resolution optical response characterization.
• Utilizing broadband optical frequency combs for measurements exceeding 1 THz bandwidth.

Main Results:

• Achieved highly sensitive strain measurements with a resolution of 34 nε.
• Demonstrated a significant improvement in dynamic range compared to conventional methods.
• Showcased enhanced multiplexing capabilities due to broadband dual-comb spectroscopy.

Conclusions:

• Dual-comb spectroscopy with optical frequency combs offers a superior approach for FBG strain sensing.
• The developed sensor system provides high resolution, broad bandwidth, and improved dynamic range.
• This technique significantly advances the capabilities of optical fiber strain sensors.