Wavelength-Tunable Erbium-Doped Fiber Ring Laser Employing an Acousto-Optic Filter

A single-stage polarization-independent acousto-optic tunable filter is used as the tuning component in an erbium-doped fiber ring laser, and continuous wavelength tuning is achieved. The frequency shift and its compensation in a ring laser cavity is analyzed in detail, the spectrum width caused by the frequency shift is shown to be far less than the full-width at half-maximum. This ring laser is theoretically analyzed and experimentally demonstrated, and a tuning range of 38 nm, starting from 1524.7 to 1562.4 nm, is observed.