为了通过实验得到向列相液晶材料的双折射率，利用迈克尔逊干涉原理设计了一种新的测量方法。在迈克尔逊干涉仪中放入楔形液晶盒，通过调节入射光的偏振方向分别实现了对寻常光和非寻常光折射率的精确测定。结果表明，该测量方法将折射率测量转换为长度的测量和干涉条纹的计数，简单易行、测量精度较高，对理论研究和实际开发液晶显示器件是非常重要的，在液晶材料和液晶器件生产中具有一定的推广价值。

In order to obtain the birefringence of nematic liquid crystal, a novel measurement method was put forward based on Michelson interference principle. A wedge-shaped cell was put into the Michelson interferometer. The refractive indexes of ordinary and extraordinary lights were accurately measured by adjusting the polarized direction of incident light. The results show that this method is simple and with high precision by converting the measurement of refractive index to the measurement of length and the counts of interference fringes. This method is very important for theoretical research and practical development of liquid crystal display devices and has some promotional value in the production of liquid crystal materials and liquid crystal devices.