为了清楚地了解菱体型消色差λ／4相位延迟器对入射角i变化的灵敏性随折射率n变化的规律，利用全反射相变公式详细推导出器件对入射角i变化的灵敏性与折射率n的关系式，并做出了理论曲线。可见，随着折射率n的增加，器件对入射角i的变化更加灵敏。结果表明，设计器件时应尽量避免选择高折射率材料。在分析相位延迟量的测量误差时，这个应用也是很有价值的。

In order clearly to learn the regularity that sensitivity to variations in the input angle of incidence i of a rhombtype achromatic quarter-wave phase retarder vary with refractive index n,the total reflection phase transformation formula are used to deduce the transmissivity formula of sensitivity to variations in the input angle of incidence i of retarders and refractive index n and draw the theoretical curves. The result indicates that retarders are more sensitive to variations in the input angle of incidence i with refractive index increasing. So the higher refractive index material should be avoided in designing retarders . This application is advantageous in analyzing error in phase retardance measurement.