马赫-曾德尔外差干涉椭偏仪是一种重要的光偏振态实时测量技术。为了提高测量系统的精度、降低误差,采用外差干涉光路分析和数值模拟的方法,理论推导了透射式马赫-曾德尔外差干涉椭偏仪光路的误差公式。结果表明,光源偏振的椭圆化程度,偏振分光棱镜消偏比及倾斜都能引起测量误差;同误差参量下待测光束不同的椭偏比和s,p分量相位差得到的测量误差不同;马赫-曾德尔外差干涉仪的误差结果与迈克尔逊外差干涉仪相近。

Mach-Zehnder heterodyne interferometric polarimeter can precisely measure the polarization state of light in real time.In order to improve the measurement precision and reduce the nonlinear error,which arises from the elliptical polarization of the laser,polarization leakage of the polarized beam splitter(PBS) and misalignment of the PBS were analyzed.The error formula was deduced.The simulation results showed that different amplitude ratio and phase difference of the measured beam had different nonlinear error output.The error was quite similar to the nonlinear error calculated in the Michelson heterodyne interferometer.