Wavelength-switchable random fiber laser based on fiber bragg grating and implementation method thereof

The invention discloses a wavelength-switchable random fiber laser based on a fiber grating and an implementation method thereof, and relates to the technical field of wavelength switching of random fiber lasers. Firstly, laser inscribing based on the femtosecond laser processing technology is carried out on the cascaded fiber bragg grating; a pump light source is connected to the input end of the wavelength division multiplexer; the first output end of the wavelength division multiplexer is sequentially connected with an erbium-doped optical fiber, a single-mode optical fiber and a total reflective mirror; and the cascaded fiber bragg grating after laser inscribing is connected to a polarization controller at the second output end of the wavelength division multiplexer and then is connected with a spectrograph. According to the invention, a femtosecond laser point-by-point inscribing method is used to prepare the fiber bragg grating of the wavelength-switchable frequency selection device, the polarization co