The main polarization mode and coupling mode in PM fiber has some optical path difference because of internal birefringence.
保偏光纤内部的高双折射，使得其内部传播的偏振主模和耦合模之间存在着一定大小的光程差。
2
Randomly varying birefringence in opticalfiber can lead to pulse broadening, corresponding to polarization-mode dispersion (PMD) effect.
光纤的随机双折射效应可导致脉冲无规展宽即偏振模色散(PMD)。
3
Using the instrument for the transmission loss of single mode of winding birefringenceopticalfiber, the spectrogram of loss and the graph of mode density are obtained.