Zhang Dengwei, Liang Cui, Li Nan
State Key Laboratory of Modern Optical Instrumentation, College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Sensors (Basel). 2020 Jul 5;20(13):3762. doi: 10.3390/s20133762.
In this paper, a novel optical approach to double the sensitivity to angular rate of interferometric fiber optic gyroscope (IFOG) is proposed. Two fiber polarization combiner/splitters (FPCSs), as the key components, are added in the traditional IFOG light path. The FPCSs are able to either combine two orthogonal polarizations transmitting at two different polarization-maintaining fibers (PMFs) into the two orthogonal axes of one PMF, respectively, or split two polarizations transmitting at the two orthogonal axes of one PMF into two polarizations to transmit at two different PMFs, respectively. Through the specific placement and coupling of these two FPCSs, the incident light can transmit twice along the polarization-maintaining fiber coil (PMFC). The novel approach is verified experimentally and the experimental results show consistency with the theoretical analysis. The proposed approach is able to double the sensitivity of IFOGs and can increase the signal-to-noise ratio (SNR) without increasing the length of PMFC, which is very susceptible to environmental influences and is of great significance in the technical improvement of IFOGs, as well as the miniaturization of IFOGs.
本文提出了一种新颖的光学方法，可将干涉式光纤陀螺仪（IFOG）对角速率的灵敏度提高一倍。作为关键部件，在传统IFOG光路中添加了两个光纤偏振合束器/分束器（FPCS）。FPCS能够将在两根不同保偏光纤（PMF）中传输的两个正交偏振分别合束到一根PMF的两个正交轴上，或者将在一根PMF的两个正交轴上传输的两个偏振分别分束到两根不同的PMF中进行传输。通过这两个FPCS的特定放置和耦合，入射光可以沿保偏光纤线圈（PMFC）传输两次。该新颖方法通过实验得到验证，实验结果与理论分析一致。所提出的方法能够使IFOG的灵敏度提高一倍，并且在不增加极易受环境影响的PMFC长度的情况下提高信噪比（SNR），这在IFOG的技术改进以及IFOG的小型化方面具有重要意义。
