文章利用Jones矩阵方法计算和分析了双折射率色散效应对一种液晶可调光衰减器(VOA)衰减能力的影响。结果表明，当激光谱线宽度较窄时，双折射率色散效应将导致液晶VOA的光衰减能力大幅度减弱；反之，双折射率色散效应对液晶VOA光衰减能力的影响可以忽略，但液晶VOA本身的光衰减能力很低。因此，液晶VOA适用于较窄线宽的激光光源，在设计和使用时应充分考虑液晶双折射率色散效应对其光衰减能力的影响。

Effects of birefringent dispersion on the capability of a liquid crystal Variable Optical Attenuator (VOA) are analyzed by the Jones matrix method. The results indicate that birefringent dispersion greatly weakens its attenuating capability when working on lasers with narrow linewidths. But when it works on lasers with wider linewidths, the effects are negligible, but inevitably accompanied with a fading attenuating capability. Therefore, it is appropriate that liquid crystal VOA work on lasers with narrow linewidths and that full consideration be given to the effects of birefringent dispersion on VOA attenuating capability in its design and application.