中文摘要：

采用单模放大和包层抽运放大的级联方式，在主振荡功率放大系统中，将平均功率0．5mw、脉宽20ns以及重复频率为50kHz的光脉冲安全放大到平均功率0．6W、峰值功率600W的脉冲输出．相应增益为30．8dB．放大输出的脉冲信号信噪比为30dB，脉冲形状基本没有发生畸变．在前置放大结构中抽运光通过级联熔融拉锥型波分复用器耦合，有效确保了抽运源（976nm）的正常工作．

英文摘要：

The fiber-based amplification of a commercially packaged, fiber pigtailed pulsed diode laser operating at wavelength of 1 064 nm （bandwidth of 0.45 nm） was reported. The cascaded Yb-doped fiber amplifier could operate safely by using cascaded fused wavelength division multiplexing （WDM） in each single mode amplification stage. The total isolation of cascaded WDM could protect the laser diodes from being destroyed by feedback of pump/signal power. At repetition rate of 50 kHz, pulse duration of 20 ns and average power of 0.5 mW,output power up to 0.6 W and peak power up to 600 W were obtained, with a high signal to noise ratio of 30 dB. The gain of the whole system is 30.8 dB and pulse distortion is not been observed.