PZT is commonly used as the phase shifter in interferometric systems with small apertures for decades. However, it becomes more difficult to be applied to the system with large aperture. In this paper, the phase shifting procedure is moved to the source module with a low coherence laser, which makes phase shifting independent of the large interference cavity. The path matching procedure based on intensity variation is introduced to compensate the path difference between the two arms. The experiments based on PZT and wavelength tuning methods are both carried out on a 600mm Fizeau interferometer for verification of the proposed method. The difference between the two results is 0.0015λ(PV). Besides, repeated experiments are performed, showing excellent repeatability and stability and the standard deviation of RMS is 0.0011λ via PZT method. The analysis of error sources is also performed, including the poor contrast and the nonlinearity of PZT. Both the experimental results and the error analysis verify the feasibility of the proposed method in large aperture interferometer.

几十年来，PZT通常在具有小孔径的干涉系统中用作移相器。然而，变得更加难以应用于具有大孔径的系统。本文采用低相干激光将相移过程移至源模块，从而使相移独立于较大的干涉腔。引入了基于强度变化的路径匹配过程，以补偿两个手臂之间的路径差异。基于PZT和波长调谐方法的实验均在600mm Fizeau干涉仪上进行，以验证所提出的方法。两种结果之间的差异为0.0015λ（PV）。此外，通过PZT方法进行的重复实验显示出极好的可重复性和稳定性，RMS的标准偏差为0.0011λ。还进行了误差源分析，包括差的对比度和PZT的非线性。实验结果和误差分析均证明了该方法在大孔径干涉仪中的可行性。