Abstract: Optical Filter can dynamically regulate the spectral bandwidth are of excellent value in laser technology，fiber communication，and other research and application fields. For example，the generation of ultrashort pulsed laser is mainly affected by parameters such as nonlinear phase shift，group velocity dispersion and spectral bandwidth. Among them，the filter bandwidth plays an important role for improving laser parameters such as single pulse energy，pulse width and average power. However，the filter bandwidth used in the generation of ultrashort pulse lasers is fixed，and it is not possible to realize real-time online dynamic tuning of the laser parameters. Aiming at solving the problems that the available filters cannot realize dynamic tuning of the laser spectrum，and the fabrication process is also complicated. This work carries out the theoretical simulation and design of the all-fiber optic filters.

Key words: polarization state, amplitude modulation, spectrum, dynamic tuning