提出了一种利用光纤式低相干技术测量光学介质折射率和群延迟色散的方法。该方法中，在系统参考臂使用步进电机扫描，干涉光信号经过光谱仪后由CCD探测，利用样品上下表面的光谱干涉信号计算相位差值，然后利用多项式拟合求出群延迟色散。其优点是系统中由于光纤而引起的参考臂与样品臂之间的色散不匹配不会影响测量结果。色散测量精度可以达到±0.2747×10-14fs2/mm。在样品臂中放入反射镜，可以测量系统色散不匹配值，该数值能够用于系统色散的定量补偿。与传统的根据半峰全宽的变化来评定色散补偿结果的方法相比，定量补偿可以提高补偿精度和减小重复计算半峰全宽的工作量,定量补偿的精度为±0.019×10-12fs2。

A method of measuring dispersion and refractive index of transparent object based on spectral fiber low coherence interferometry is proposed, in which the path length of the reference arm is changed by a step motor and the interferometric signals are measured by a CCD detector. The difference between the signals from the upper and lower surfaces of a transparent plate is found and a polynominal fitting-based method is used to find the group delay dispersion. One advantage of the method is that the value of the measured dispersion is not affected by the dispersion introduced due to the mismatch between dispersions of the sample and reference arms of the system. The accuracy of the dispersion measurement is ±0.2747×10-14fs2/mm. By placing a reflective mirror in the sample arm of the interferometer, the values of dispersion mismatch can be measured and can be employed to quantitatively compensate the system dispersion. Compared with traditional methods of measuring variation of the full width at half maximum (FWHM), the proposed method can improve the accuracy and efficiency of the dispersion compensation. The dispersion compensation accuracy achieved is ±0.019×10-12fs2.