提出了一种基于Sagnac环干涉结构的光梳状滤波器。该结构利用保偏光纤双折射效应产生梳状滤波响应，通过控制Sagnac环内相位调制器的驱动信号实现光学滤波器陷波深度与滤波波长的独立调谐。利用Jones矩阵对所提出的Sagnac环光滤波器的滤波响应函数进行研究，通过分析得到光滤波器的陷波深度和滤波波长分别与射频信号和直流偏压之间的关系。在此基础上构建实验链路，验证了系统的理论分析，实现了光滤波器陷波深度在0 dB~30 dB范围内的灵活控制；通过设置直流偏压在0~12 V范围内变化，实现了光滤波器滤波波长在一个自由光谱范围（0.5 nm）内的连续可调，波长调谐效率为0.043 nm/V。

An optical comb filter based on the Sagnac ring loop is proposed. The comb filter response function is generated on the basis of the birefringent effect of the polarization maintaining fiber (PMF) within the loop. By utilizing the radio frequency (RF) signal along with the direct current (DC) to drive the phase modulator (PM) inserted in the Sagnac loop mirror, the independent tunings of the notch depth and filtering wavelength are realized. The response function of the proposed Sagnac filter is expressed theoretically with Jones matrix, and the effects of the optical filter notch depth and filtering wavelength on RF signal and the DC bias are analyzed. Based on the analysis results, the experimental link is set up to verify the theory. The results show that the tunable range of the notch depth from 0 dB to 30 dB is achieved. Besides, the filtering wavelength influenced by the DC from 0 to 12 V is continuously adjustable in the free spectral range (FSR) of 0.5 nm, and the wavelength tuning efficiency is 0.043 nm/V.