增加光栅长度是获得具有低插入损耗、高边带抑制度的超窄带光栅滤波器最佳途径, 但是长光栅的制作方案会引入比较严重的相位误差, 严重影响到光栅滤波器的性能；取样光栅的设计制作方案具有滤波中心波长设计灵活、制作精度低和切趾技术实现容易的优点。针对利用取样光栅制作超窄带光栅滤波器的方案, 分析了3种常见相位误差对-1级子光栅滤波性能的影响；利用重构等效啁啾技术(REC)成功补偿了光栅长度为6.6 cm的超窄带取样光栅滤波器-1级子光栅的相位误差, 并得到了反射谱和透射谱对称性良好,3 dB带宽为26 pm,20 dB带宽为70 pm,插入损耗为1.25 dB和边带抑制度为21.55 dB的超窄带光栅滤波器。

Increasing the grating length is the best way to realize super-narrow bandwidth filter with low insertion loss and high sidelobes suppression, but the phase error induced in the fabrication process of long grating deteriorates the performance of grating filter to a large extend. Sampled fiber Bragg grating (FBG) have the advantages of flexible wavelength design, low manufacture precision and easily realizable apodization. The scheme of super-narrow bandwidth filter based on sampled FBG is taken emphasis on, and the influence of three kinds phase error on the filter performance of -1st ghost grating is analyzed, which provides reliable guide for future long grating fabrication. The phase error of a fabricated sampled FBG with length of 6.6 cm is compensated using reconstruction equivalent chirp (REC), and a super-narrow filter with symmetric reflection and transmission spectrum, insertion loss of 1.25 dB, sidelobes suppression of 21.55 dB, 3 dB bandwidth of 26 pm and 20 dB bandwidth of 70 pm is obtained.