实验研究了主动调Q掺镱光纤激光器(YDFL)中放大自发辐射(ASE)对调Q脉冲形成和演化的影响。结果表明,尾纤型声光调制器(AOM)打开过快和掺镜光纤(YDF)增益瞬态特性间的综合相互作用结果,使得注入至腔内的初始宽带ASE形成功率波动,并在腔内循环放大,导致输出脉冲呈多峰结构;而注入的宽带ASE因功率过高会导致YDF的增益自饱和效应,制约高增益的获取,使激光器难以获得调Q激光脉冲,输出脉冲主要为调Q的ASE脉冲;通过引入光纤布拉格光栅(FBG),可以有效抑制YDF中因ASE产生的增益饱和效应,YDF工作在高增益状态,有利于获得低阈值、窄脉宽和高峰值功率的调Q激光脉冲。引入FBG后,在160 mW抽运时,实验测得的调Q激光脉冲峰值功率和脉宽分别为40.7 W和30 ns。 The effect of amplified spontaneous emission (ASE) on Q-switched Q-pulse formation and evolution in a Q-switched Yb-doped fiber laser (YDFL) was investigated experimentally. The results show that the combined effects of the fiber pigtail acousto-optic modulator (AOM) switching too fast and the YDF gain transient characteristics make the initial broadband ASE implanted into the cavity form power fluctuations, The inner loop amplification causes the output pulse to have a multi-peak structure. However, the injected broadband ASE will cause the gain self-saturation effect of the YDF due to the high power, which restricts the gain of the gain and makes the laser difficult to obtain the Q-switched laser pulse. Q ASE pulse. By introducing fiber Bragg grating (FBG), YDF gain saturation effect due to ASE can be effectively suppressed, YDF work in high gain state, which is conducive to obtain low threshold, narrow pulse width and high peak power Q Laser pulse. After the introduction of FBG, the peak power and pulse width of the Q-switched laser pulses measured at 160 mW pumping were 40.7 W and 30 ns, respectively.