为了能够测量带有补偿器的液晶相位可变延迟器(LCVR)在不同电压值下的相位延迟,提出了一种基于斯托克斯矢量和穆勒矩阵的测量方法。在可见光范围内6个波长下实验测量了LCVR在2kHz方波、0~10V电压下的相位延迟。结果表明,LCVR具有调谐电压低、控制简单、调节范围大、无需转动等优点,相位延迟的测量误差〈0.6%。根据延迟器件的特性,建立了相位延迟的拟合函数公式,采用最小二乘曲线拟合的方法得到了延迟器件工作范围内全部波长、全部电压值下的相位延迟,曲线拟合的标准差〈0.022,。提出的测量方法、测量结果和拟合函数的建立对偏光器件的研究有一定的参考价值。
A new method is presented based on a Stokes vector and a Mueller matrix to measure the retardation of a Liquid Crystal Variable Retarder (LCVR) attached with a compensator, a 2 kHz square wave with the adjustable amplitudes 0-10 V is used to control the LCVR and the retardation is measured at six wavelengths in a visible region. The experimental results show that the LCVR has the advantages of low voltage controlling, simple operation, wide adjustment ranges and no mechanical rotating,and the error of measurement is less than 0.6 %. The fitting function is established based on the characteristics of the retarders,and the retardations of all wavelengths and all voltages in the working condition of the retarders are obtained by the least-square curve fitting. The standard error of curve fitting is less than 0.02),. The measurement method, experimental results and the fitting function provide a reference for the polarization device research.