为了实现平坦度更好、光谱覆盖可见光波段的超连续谱激光输出, 研究了泵浦波长可调谐的全光纤结构超连续谱光纤激光器。设计搭建了一台非线性偏振旋转锁模脉冲光纤激光器, 实现了9种中心波长的耗散孤子皮秒脉冲输出, 波长调谐范围为1 041~1 076 nm; 以它作为种子源进行了两级功率放大, 并泵浦10 m 长的光子晶体光纤, 在泵浦激光功率为500 mW时, 得到9种输出光谱特性不同的超连续谱激光, 得到当泵浦激光中心波长为1 050 nm时, 更利于实现光谱范围更宽、平坦度更好、可见光分量更多的超连续谱激光输出。为进一步拓宽超连续谱激光的光谱范围、提升光谱平坦度, 将泵浦激光功率提升至1.45 W, 最终实现了输出功率为600 mW、短波边界为470 nm、600~1 700 nm内10 dB光谱宽度为1 053 nm的超连续谱激光输出。

In order to realize supercontinuum (SC) generation with broadband spectral range covering more visible wavelength, a pump wavelength tunable all-fiber SC fiber laser was experimentally investigated. A tunable nonlinear polarization rotation mode-locked fiber laser was proposed, which could output picosecond dissipative solitons pulse with nine different central wavelengths from 1 041 to 1 076 nm. After two-stage power amplifier, the tunable laser with relatively high power was coupled into 10 m long photonic crystal fiber, SC with nine different output spectra was realized when the pump laser power was 500 mW. And it was found that when the pump laser central wavelength was 1 050 nm, the generated SC was with broad and flat spectrum and containing a large part of visible wavelength components. To further broaden the SC spectral range and obtain better flatness, the pump laser power was enhanced up to 1.45 W, the generated SC output power was 600 mW, while the short-wavelength boundary was 470 nm, 10 dB spectral bandwidth was 1 053 nm within 600—1 700 nm wavelength range.