Research Of SOA Based Wavelength-swept Fiber Ring Laser

Fiber laser technology is one of the key technologies in optics. With the advantages of small size, narrow bandwidth, low threshold, multi-wavelength and high coupling efficiency, it is widely used in fiber sensors, fiber-optical communication, industry processing, weapon and so on.A kind of tunable fiber ring laser based on SOA is studied in this paper. Based on the theory of tunable fiber ring laser, the theoretical model of SOA based tunable fiber ring laser was built. By means of theoretical analysis and numerical simulation about the gain characteristic of SOA, threshold current, EQE and output power were discussed. Besides, the characteristic curve of tunable F-P filter was analysed. According to those theory, the splitting ratio of coupler and the structure of resonant cavity can be chosen so that the capability of tunable fiber ring laser will be improved. Based on theoretical analysis, a experimental system of SOA based tunable fiber ring laser was built. Three work modes, single-wavelength, swept multi-wavelength and consecutive wavelength, were implemented. Output characteristics of this three work modes were also measured. A time domain display method of wavelength of tunable fiber ring laser based on filter the characteristics of WDM was successfully demonstrated. Under the multi-wavelength scanning mode and consecutive wavelength mode, the changes of wavelength were observed in time domain.