为了对双折射滤波器中晶体片厚度需要达到的精度进行定量分析，根据双折射滤波器的滤波原理，引入了晶体片材料的双折射率色散，得出了晶体片的厚度偏差、相位延迟量偏差、目标波长移动量之间的关系，最后进行了模拟验证。结果表明，对于铌酸锂晶体制作的晶体片，材料的双折射率色散是不可忽略的，基于它得到的厚度精度是保证滤波器性能的必要条件，这些研究结论对于高性能双折射滤波器的实际制作有重要的参考价值。

In order to make quantitative analysis to the accuracy crystal thickness in the birefringent filters, based on the fundamental filter theory, by introducing the birefringent dispersion of crystal, the exact relationship of crystal thickness accuracy, phase retarder deviation and spectrum shift is built up. Theoretical analysis and simulation are put forward strictly. The results show that the birefringent dispersion cannot be neglected when using LiNbO3 as the materials of plates and that the crystal thickness accuracy can ensure a good transmission spectrum, which may be useful for constructing high-performance birefringent filer.