watts-level ultra-short wavelength operation of a tm-doped all fiber laser was developed by using a 1550 nm er-doped fiber laser pump source and a pair of fiber bragg gratings (fbgs). the laser yielded 1.28 w of continuous-wave output at 1707.01 nm with a narrow linewidth of similar to 44 pm by means of a 20 cm tm-doped fiber. the dependencies of the slope efficiencies and pump threshold of the tm-doped fiber laser versus the length of active fiber and reflectivity of the output mirror (fbg) were investigated in detail, in which the maximum average slope efficiency was 36.1%. there is no doubt that this all fiber laser will be a perfect pump source for mid-ir laser output.