Polarimetric distributed feedback fiber laser sensor for simultaneous strain and temperature measurements

Area of Science:

• Optics and Photonics
• Fiber Optic Sensing Technology
• Materials Science

Background:

• Distributed feedback (DFB) fiber lasers offer unique spectral properties.
• Simultaneous strain and temperature sensing is crucial for structural health monitoring and industrial processes.
• Accurate, real-time measurement capabilities are needed in various scientific and engineering fields.

Purpose of the Study:

• To demonstrate the application of a dual polarization DFB fiber laser as a simultaneous strain and temperature sensor.
• To evaluate the accuracy and performance of this novel sensing approach.
• To investigate the self-heating characteristics of the DFB fiber laser.

Main Methods:

• Utilizing a dual polarization DFB fiber laser.
• Measuring the absolute wavelength of one polarization.
• Measuring the polarization beat frequency.
• Correlating wavelength and beat frequency shifts to strain and temperature changes.

Main Results:

• Simultaneous and accurate determination of strain and temperature.
• Achieved sensor accuracy of +3 microepsilon for strain and +/-0.04 degrees C for temperature.
• Successfully measured the self-heating of the DFB fiber laser as a function of pump power.

Conclusions:

• The dual polarization DFB fiber laser is a viable and accurate sensor for simultaneous strain and temperature measurement.
• This technology offers high precision for demanding sensing applications.
• The sensor can also be used to characterize the thermal behavior of the laser itself.