Study Of The Wide Tunable Range And Narrow Line Width Erbium-Doped Fiber Laser

As a new light source, tunable fiber laser is very attractive due to the applications not only in wavelength-division-multiplexing fiber communication system, but also in the fields of coherent communication, fiber sensor and spectrum analysis. Tunable erbium-doped fiber laser using an integrated optics acousto-optical tunable wavelength filter (AOTF) is studied. This tunable fiber laser has many advantages comparing with other designs such as wide tunable range, narrow line width, quick tuning speed, easy and reliable tuning and compatible with fiber system, and more feasibility and practicability in economy than other projects.The research is done based on the devices that have been completed and studying in our laboratory, and is composed of two main parts: 1. the theory analysis on the output characteristics of acousto-optical tunable erbium-doped fiber laser. Considering practical study and using other related treatise, the output characteristics of the two-stage acousto-optical tunable erbium-doped fiber laser is studied in details, and the relations between the output characteristics and factors which influence the devices on the characteristics are analysed. A series of figures of output characteristics, which provide important reference for the design of laser, are attained by Matlab program. 2. A new-style wide tunable range and narrow line width erbium-doped fiber ring laser is presented. The AOTF which suit to ring laser is employed as a tunable device, and an unpumped erbium-doped fiber (low dopant) which used as the transient grating is inserted in the cavity to narrow the linewidth, and good theory results were achieved.