Fiber laser and coupling method thereof

The invention relates to an optical fiber laser which comprises a shell, a signal transmitting chip and a pumping chip, the signal transmitting chip and the pumping chip are both coupled and packaged in the shell, the shell is connected with a light emitting optical fiber and a collimation rare earth doped amplification optical fiber, and the collimation rare earth doped amplification optical fiber is communicated with a Faraday rotating mirror; signal light output by the signal transmitting chip is processed by the first light path assembly, is input into the Faraday rotating mirror through the collimation rare earth doped amplification optical fiber, returns to the shell and is output by the light emitting optical fiber; and a pumping light signal output by the pumping chip is processed by the second light path assembly and then is input into the collimation rare earth-doped amplification optical fiber. The invention further provides a coupling method of the fiber laser. According to the invention, only the