Application Of Fiber Bragg Grating In Er³⁺-Doped Fiber Laser

Tunable fiber laser is not only an important kind of device in wavelength-division-multiplexing fiber communication system, but also can be used 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 is studied, which has many advantages such as wide tunable range, narrow line width.The research is based on FBG as the filter by reason of acousto-optical tunable filter is during the experiment .The research is composed of three main parts: 1.Introduce the theory of acousto-optical tunable Erbium-doped fiber laser .2.Research on fiber bragg grating, what is analyzed is the application of FBG in Tunable Er3+-Doped Fiber Laser, which is based on the filter charactor. The application is about the saturated absorber part and the filter part.3.The experiment about the tunable Er3+-Doped Fiber Laser. Analyse the result of line-frame and circle-frame experiment. Because the losses are difference, the threshold of circle- frame is higher than line- frame. The light can be absorbed sufficiently, so the output of circle-frame is better than line-frame. The conclusion is that, when the length of fiber is fixed, different frames lead to different threshold, and the FWHM is different. The result of experiment is proved theoretically.