为了对石英晶体在通讯波段1 310 nm处的双折射率进行精密测量， 基于椭偏光谱仪对P和S两方向上偏振光相位差的精密测量原理， 在透射模式下， 通过对琼斯矩阵的分析， 设计了一种精密测量晶体双折射率的方法， 并在室温（22 ℃）下对通讯波段1 310 nm处石英晶体的双折射率进行了精密测量， 测量结果和对误差的分析显示， 此方法给出的双折射率测量值的精度高达10-6量级， 为目前可查阅的最高精度， 对于提高石英晶体相位延迟器件的设计精度具有重要的意义。

In order to get the precision measurement of birefringence of quartz crystal at the communication wavelength1310nm, based on the principle of precision measurement of phase difference between P and S polarized lights of spectroscopic ellipsometer, a method for precision measurement of birefringence of crystal was designed through the analysis of the Jones matrix under the transmission mode, and the precision measurement of birefringence of quartz crystal at 1 310 nm at room temperature (22 ℃) was made, the measuring results and error analysis show that the precision reached 10-6 level, this is the most precise birefringence parameter available, and it is of important significance for the improvement of designing precision of phase retardation devices of quartz.