基于偏光干涉理论用3种不同的波长(405 nm、635 nm、904 nm)的激光在3种不同温度条件(25 ℃、40 ℃、60 ℃)下测量、分析了向列相液晶相位延迟器的双折射率色散特性, 并由柯西色散公式拟合得到了在上述3种温度条件下的色散方程。结果表明, 该方法可以有效地测量、分析向列相液晶的双折射率色散特性。根据该液晶在25　℃温度条件下的色散方程推算出了589　nm波长处的双折射率为0.268, 该结果与液晶数据表提供的数值0.257的偏差值为4.28%。该研究为液晶双折射色散特性的研究提供了一个新的方法, 同时也为液晶可调相位延迟器件的设计与应用提供了依据和参考。

Birefringence dispersion characteristics of nematic liquid crystal tunable phase retarder are measured and analyzed by using the theory of polarized light interference with three different wavelength (405 nm, 635 nm, 904 nm) lasers at three different temperature condition ( 25 ℃, 40 ℃, 60 ℃). And the Cauchy dispersion formulae are obtained by fitting with the data at the three wavelengths and three temperature conditions. It is shown that this method is effective to analysis the nematic liquid crystal birefringence dispersion characteristics. The liquid crystal birefringence at 589 nm and 25 ℃ is deduced. The birefringence value is 0.268, it only has about 4.28% deviation with the published data (0.257) from the liquid crystal product datasheet. This study provides a new way to character the liquid crystal birefringence, and the results can be used as a reference for the liquid crystal tunable devices design and application.