Highly Stable Gyroscope Composed of Panda-Type Polarization-Maintaining Fiber Coil With Strong Resistance to Thermal Stress

The thermal stress disturbance experienced on polarization-maintaining fiber (PMF) coils has become the key factor that limits their stability, directly affecting the accuracy of fiber sensors. Here, we present a high-stability Panda-type PMF with enhanced anti-thermal stress disturbance ability by a collaboration of optimized stress-applying parts (SAPs) and double-coating structures for interferometric fiber optic gyroscope (IFOG) applications. The error sources of the gyroscope and the requirements for the performance of PMFs are analyzed using the finite element model, and the target fiber design is selected for practical fabrication. Experimental evaluations of thermal performance conducted from the aspects of the fiber, wound fiber coils, and built IFOGs are performed between −40 °C and 60 °C with different temperature change rates. The fluctuation in extinction ratio (ER) of this coil is significantly reduced to 2.95 dB, corresponding to over onefold decrease over conventional PMF coils of 6.92 dB; and the output bias stability (OBS) of the assembled IFOG is greatly improved from 0.12 to 0.074 °/h. The test results demonstrate the proposed design basis that the optimized PMF with strong anti-thermal stress disturbance ability achieves excellent temperature stability of the IFOG, which serves as a valuable guide for improving the sensing precision.