Tunable multi-wavelength fiber laser and control method thereof

Abstract

The invention provides a tunable multi-wavelength fiber laser and a control method thereof. The tunable multi-wavelength fiber laser comprises a pump light source, a first wavelength division multiplexer, a gain medium, a first optical isolator, an optical circulator, an optical coupler, a second optical isolator and a tunable multi-wavelength optical wave filter which are sequentially connected in series, wherein the pump light source is connected with a first input end of the first wavelength division multiplexer, an output end of the first optical isolator is connected with a first port ofthe optical circulator, an input end of the optical coupler is connected with a third port of the optical circulator, and a first output end of the optical coupler outputs laser; the input end of thesecond optical isolator is connected with the second output end of the optical coupler, and the output end of the second optical isolator is connected with the second input end of the first wavelengthdivision multiplexer to form a closed optical path; the tunable multi-wavelength light wave filter comprises a period adjusting device, and a first fiber bragg grating and a second fiber bragg grating which are connected in series; the input end of the first fiber bragg grating is connected with the second port of the optical circulator; and the period adjusting device adjusts the period of the fiber bragg grating.

Description

technical field [0001] The invention relates to the technical field of communication, in particular to a tunable multi-wavelength fiber laser and a control method thereof. Background technique [0002] Fiber laser has many advantages such as high output power, good beam quality, high conversion efficiency, low threshold, narrow line width, multiple output wavelengths, good compatibility and simple structure. Processing and full-color display and other fields have broad application prospects. In addition, with the development of optical fiber communication technology, the optical fiber communication system has higher requirements on transmission capacity, and the optical wavelength division multiplexing system has also become an indispensable part of the communication system. [0003] There are two ways to achieve multi-wavelength lasing in traditional multi-wavelength fiber lasers: one is to use a separate gain medium for each wavelength; the other is to suppress the mode c...

AI Technical Summary

Problems solved by technology

For the second method, since the gain of the erbium-doped fiber has a uniform broadening characteristic at room temperature, this will cause mode competition in the laser, and the multi-wavelength laser output cannot be established stably. In the traditional method, liquid nitrogen is used to cool the doped fiber. Erbium fiber to suppress competition, but it is not suitable for practical applications due to its too harsh temperature requirements

Also based on the nonlinear effect to suppress the mode competition in the laser cavity, the system is to increase the nonlinear effect through several kilometers of single-mode fiber or expensive high nonlinear fiber, resulting in a very complicated system structure

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