The Pressure Sensing Method Based on Polarization Properties in Fiber

The focus of this talk is on the method and technologies of pressure sensor based on polarization properties in fiber. The working principle is the proportional relationship between Stokes parameters and applied pressure. Hence real-time pressure measurement is achieved through direct measurement of the Stokes parameters. Using a cantilever beam the displacement measuring is also achieved. The optimizations of the sensor are discussed. The measurement range is increased by 5 times using the fusion of multi-Stokes parameters. In addition, aiming at improving both sensitivity and linearity, a novel and fast optimization scheme for the optimal incident SOP (state of polarization) is proposed, which is based on the Muller matrix instead of the previous “blind adjustment The sensitivity and linearity obtained in the vibration experiments agree well with the theoretical expectation. In order to meet the requirement for monitoring high frequency dynamic pressure or transient pressure, a design using a PBS (polarization beam splitter) is proposed to demodulate the polarization information. The simple and all-fiber configuration, low-cost and high-speed potential make it promising for fiber-based dynamic pressure sensing. And this type of sensor has potential for measurement of other measurand, e.g. acceleration, acoustic and ultrasonic signal. We also take a look at the future prospective at the research directions and challenges in this area at last.