单检偏器数字散斑干涉偏振相移方法

A single-polarization-analyzer-based polarization phase-shifting method in digital speckle pattern interferometry

针对曾经提出的数字散斑干涉时间偏振相移方法[1]所存在的结构复杂、操作不便等不足,提出了一种优化的数字散斑干涉偏振相移方法。不同于原先方法需要两组固定波片和可动检偏片,本方法仅需一组固定波片和可动检偏器即可实现相移,因此系统结构和操作过程都更加简单,且减少了光路调节不准所带来的相移误差,相位图质量更高。实验结果显示,结合传统的三步、四步、五步相移算法,基于单检偏器偏振相移器的数字散斑干涉方法能够获取质量较好的相位图,因此证明了这种方法可有效替代原方法。

An optimized polarization phase-shifting method in digital speckle pattern interference based on a single polarization analyzer is proposed to solve the problems of complex structure and inconvenient operation of temporal polarization phase-shifting for digital speckle pattern interferometry[1].Different from the former method which requires two sets of fixed wave plates and movable polarization analyzers;this method only needs one set of fixed wave plate and movable polarization analyzer to achieve the phase shifting.Therefore,the system structure and operation process are simpler,and the error of phase shift caused by inaccurate optical path adjustment is minimized,leading to higher-quality phase maps.Experimental results show that the digital speckle pattern interferometry with polarization phase shift based on a single polarization analyzer,combining with the traditional three-,four-,five-step phase-shifting algorithms,is able to obtain high-quality phase maps,verifying that the proposed method is an effective alternative of the former method.