We have proposed and demonstrated a multi-wavelength-switchable and uniform erbium-doped fiber laser using unbalanced in-line Sagnac Interferometer. By employing this simple scheme and through the proper control of the polarization controller, we were able to achieve uniform multi-wavelength operation of up to 84 laser lines with the signal-to- noise ratio over 20dB and 0.8-nm wavelength switching at room temperature. Again, we generated more than 300 lines, 0.1-m wavelength switching and good power stability (≤ 0.2dB) over 1570nm-1610nm in the experiment.
