Widely tunable compact Er3+-doped fiber ring laser

A widely tunable compact erbium-doped all fiber ring laser with 104nm turning range was reported. A fiber Fabry-Perot filter (FFP-TF) was used to be the tuning element to realize turning range from 1513nm to 1617nm with the linewidth less than 40 pm at any wavelength. The fiber laser worked with slope efficiency of above 10% and threshold of less than 21mW. This fiber laser can be used to realize wavelength interrogation with a relatively high speed and high resolution.