1/4波片相位延迟分布的动态测量

通过密勒矩阵和斯托克斯参量法对一种1/4波片的相位延迟分布的测量模型进行了推导,并设计出一种空间分光移相器,取代一般测量系统中的检偏器,使得系统能于瞬间同时采集四幅具有90°移相步长的干涉图,避免了环境振动对测量的影响,从而可以对1/4波片的相位延迟分布进行动态在线测量.对一个实际标称波长632.8 nm的1/4波片进行了测量,结果显示其平均延迟量为149.36 nm,且接近75%部分其相位延迟误差在5 nm之内,显示出较好的延迟均匀性.

Dynamic Phase-shifting Interferometry for Full Field Retardation Distributing of Quarter Wave Plate

The measurement model for the retardation distributing of the quarter wave plate was introduced by Muller matrix and Stokes parameter.And four patterns with phase shifting of 90°in turn were catched simultaneously by an especial spatial splitting phase-shifter.Therefore,the introduced system has anti-vibration performance and the dynamic testing on line may be performed.An actual measurement of a quarter wave plate which wavelength is 632.8 nm was given out finally.Its averaging retardation was 149.36 nm,and there is about 75% of the testing area whose retardation error is less than 5 nm.So it had fine retardation uniformity.