Abstract
The paper presents a polarization maintaining photonic crystal fiber sensor for dynamic pressure measurements based on a Sagnac loop filter (SLF). The SLF was illuminated by a beam reflected off a uniform fiber Bragg grating. This way a conversion of the shift of the SLF's spectrum into a change of light intensity was achieved. The pressure acting on the polarization maintaining fiber of the SLF induces a shift of its spectrum, which results in a change of the intensity of its transmitted and reflected beams in opposite directions. This makes it possible to adopt the ratio detecting method to obtain an output signal of the sensor, which is independent of light source power fluctuations. The non-linearity error of the designed and produced sensor is smaller than 1.0% in the measurement range from -0.08 to 0.2 MPa. Results of measurements of pressure steps obtained using the presented sensor are provided together with results obtained using a strain gauge sensor.