We demonstrate a widely tunable ytterbium-doped single frequency all-fiber laser with a computer-controlled tunable filter and a home-made comb spectrum filter. The comb filter is realized by fusing a single strand of polarization maintaining optical fiber into a double-circulator interferometer. The spectral performance of the comb filter is verified by theoretical and experimental studies. Wavelength-tunable single frequency operation in about 55 nm (1030–1085 nm) range can be achieved through the combined effect of these two filters. The experimental outcomes exhibit that an ultra-narrow linewidth of 435 Hz with high optical signal to noise ratio greater than 50 dB and high stability of operation wavelength and output power (0.016 nm and 0.38 dB, respectively) at room temperature. Our studies provide a new way to obtain the wide-range tunable single frequency fiber laser.

我们演示了具有计算机控制的可调滤光片和自制梳状光谱滤光片的可调谐掺单频全光纤激光器。梳状滤波器是通过将单束保偏光纤融合到双环干涉仪中来实现的。理论和实验研究证明了梳状滤波器的光谱性能。通过这两个滤波器的组合效果，可以实现约55 nm（1030–1085 nm）范围内的波长可调单频工作。实验结果表明，在室温下，超窄线宽为435 Hz，光信噪比高，大于50 dB，工作波长和输出功率（分别为0.016 nm和0.38 dB）具有较高的稳定性。