Real-time transverse force sensing using fiber Bragg grating through direct Stokes parameters measurement

Area of Science:

• Optics and Photonics
• Sensor Technology
• Materials Science

Background:

• Fiber Bragg Gratings (FBGs) are widely used in sensing applications.
• Real-time force measurement requires efficient and accurate sensing methods.
• Polarization properties of light can be utilized for enhanced sensor performance.

Purpose of the Study:

• To characterize a novel fiber Bragg grating (FBG) transverse force sensor.
• To investigate the use of Stokes parameters for real-time force measurement.
• To analyze the influence of incident light's state of polarization (SOP) on sensor sensitivity and dynamic range.

Main Methods:

• Direct measurement of Stokes parameters at a single wavelength.
• Theoretical and experimental investigation of SOP dependence.
• Linear fitting to establish the relationship between Stokes parameters and applied force.

Main Results:

• A proportional and linear relationship was observed between Stokes parameters and applied force.
• Maximum experimental sensitivity of 0.037/N was achieved.
• Sensitivity and dynamic range were found to be dependent on the incident light's SOP.

Conclusions:

• The developed FBG transverse force sensor based on Stokes parameters enables real-time force measurement.
• Adjusting the incident SOP can further enhance sensor sensitivity.
• The simplified system design and improved data processing speed offer significant practical value for FBG sensing.