Abstract A novel method, which is based on the phase difference between the filtered spectrum and simulated spectrum, is proposed to compensate for the optical path difference (OPD) demodulation error of the interferometer sensors. With applying the phase difference technology, large dynamic range OPD demodulation with high accuracy is realized. Its principle is deduced by theoretical analysis. The numerical simulation is conducted in the presence of noise, amplitude variation, and constant offset, verifies that the proposed method is robust. The strain experiment result shows that the demodulation resolution is 45.37 pm at the cavity length of around 328 μm. The demodulation accuracy improves about 10,000 times compares with the DGT method, and the demodulation resolution is achieved to the same order as the most advanced method with less computation. And the phase difference technology can be applied to other demodulation methods for high demodulation accuracy.

中文翻译：

---

一种基于相位差技术的高精度光程差补偿新方法

摘要 提出了一种基于滤波后光谱与模拟光谱相位差的干涉仪传感器光程差(OPD)解调误差补偿方法。应用相位差技术，实现大动态范围、高精度的OPD解调。其原理是通过理论分析推导出来的。数值模拟是在存在噪声、幅度变化和恒定偏移的情况下进行的，验证了所提出的方法是稳健的。应变实验结果表明，在328 μm左右的腔长处解调分辨率为45.37 pm。解调精度比DGT方法提高约10,000倍，并且解调分辨率达到与最先进的方法相同的数量级，计算量更少。并且相位差技术可以应用到其他解调方法中以获得高解调精度。