Multi-order and tunable Raman amplification method based on self-similarity amplification technology

The present invention relates to a multi-order and tunable Raman amplification method based on a self-similarity amplification technology. Laser signals are subjected to multi-level amplification by amulti-level pre-amplification portion, then are input into a pulse timing sequence selection module and a pulse compression module in order and are output from a Raman output module, the Raman outputmodule is configured to divide the output energy into two paths through a feedback module, wherein one path is connected with a spectrograph, the repetition frequency corresponding to the output critical power when high-order Raman is generated is taken as feedback signals which are sent back to the pulse timing sequence selection module to achieve modulation of the injection pulse repetition frequency; the other path is connected with an autocorrelator to select the optimal optical grating distance which is fed back to the pulse compression module to achieve broadening of the Raman spectrum;and finally, the Raman out