Improved the original NALM mode locking technology by introducing a phase offset, and introduced the dispersion compensation into the cavity to ensure the stability of mode locking self-starting, while greatly increasing the spectral width of the mode locking pulse. At the same time, it utilizes a new type of self-developed integrated packaged fiber-optic-device greatly shortens the cavity length of the resonant cavity and obtains a very high mode-locked pulse repetition frequency (500 MHz-1 GHz).