Design of high-sensitivity photoelastic optical fiber pressure sensor: A differential approach

A differential method is described for the optical fiber photoelastic pressure sensor to implement high sensitivity and low drift optically, The method relies on importing two orthogonal polarization light beams into the system alternatively in time to produce two differential output signals that are derived from the conventional compensation methods. The difference of the two output signals can reduce the long-term drift significantly, The measurement range of 0 similar to 0.15 MPa has been demonstrated with accuracy of 0.1% within the temperature range of -20 degrees C similar to 50 degrees C. The practical application proves its efficiency.