A real-time displacement reconstruction technique based on a phase retardation method is proposed. By introducing a waveplate and a polarization beam splitter into the external cavity, two self-mixing signals with a phase shift of $\pi ∕2$ can be obtained. Then the displacement of the external object can be reconstructed by a quadrature demodulation algorithm, which significantly simplifies the data processing and meets the requirements of real-time displacement reconstruction techniques. The results show that the absolute errors of the reconstructed displacements are less than 75 $\mathrm{nm}$.

中文翻译：

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基于自混合干涉仪相移的正交相位检测用于实时位移测量

提出了一种基于相位延迟法的实时位移重建技术。通过将波片和偏振分束器引入外腔，两个自混合信号的相移为$\pi ∕2$可以获得。然后可以通过正交解调算法重建外部物体的位移，大大简化了数据处理，满足实时位移重建技术的要求。结果表明重建位移的绝对误差小于75$\mathrm{纳米}$.