为改善全光纤3×3 光学梳状滤波器(Interleaver)的输出特性，详细推导了其输出表达式，通过分析和优化，提出了新的结构参数。计算结果表明: 相对于以往的全光纤3×3 光学梳状滤波器而言，利用优化后的结构参数设计的全光纤3×3 光学梳状滤波器，不仅降低了器件的制作难度，而且在串扰特性、信道隔离度、阻带抑制、通带平顶度以及过渡带滚降等特性方面得到了明显改善，信道间功率旁瓣降低了约16 dB。最后进行了实验研究，实验所得结果与理论结果相吻合。

In order to improve the transmission performance of the all-fiber 3×3 interleaver, the output expression is derived and simulation is performed. Through the analysis and optimization, the optimal structure parameters is put forword. The calculating and experimental results indicate that the crosstalk characteristics, the channel isolation, stopband rejection, passband flat-topped degrees and the rolloff in transition band can be improved greatly, and the reduced sidelobe level of channel of the proposed device is more than 16 dB in comparison with that of the convention all-fiber 3×3 interleaver. A 100 GHz three-port interleaver with a flat-topped passband bandwidth is demonstrated by experiment. The experimental and theoretical results coincide with each other.