Abstract: The paper presents a design of fiber optic sensor for the simultaneous measurement of a dynamic and quasi-static force, which is based on intensity modulation. The sensor uses a Sagnac loop filter with a polarization-maintaining photonic crystal fiber, which is simultaneously subjected to transverse dynamic and quasi-static forces. The Sagnac loop filter was illuminated by the reflected beam of a fiber Bragg grating, as
a result of which in intensity demodulation in the sensor was obtained. The measurements of the sensor characteristics show that its sensitivity is 0.0381V/N, and the nonlinearity error does not exceed 3.5%. The sensor features low temperature sensitivity, which results from a partial temperature self-compensation, which in turn results from different temperature coefficients of the Sagnac loop filter with the polarization maintaining photonic crystal fiber and the fiber Bragg grating.
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