设计并研究了Nd：YVO₄自锁模皮秒激光器，探究了激光器的最佳锁模条件。观察并分析了自锁模皮秒激光器准周期锁模、倍周期锁模状态，研究并测量了结构紧凑的直腔自锁模激光器的输出特性。谐振腔为凹平直腔，Nd：YVO₄晶体作为激光增益介质和克尔介质，在未加其他锁模元件的情况下，实现了1 064 nm高效率连续锁模脉冲激光输出。晶体距输入镜16 mm、腔长为90 mm时，对1 064 nm透过率分别为10%、20%、30%和50%的四种输出镜下激光器的输出特性进行了对比分析。对激光器进行优化设计，输出镜透过率为10%，泵浦功率为8 W时，激光器输出功率为2.76 W，斜效率高达43.2%，锁模脉冲重复频率为1.43 GHz，激光器实现了高效、稳定的连续锁模。

The Nd：YVO₄ self-mode-locked picosecond laser was designed and studied, and also the best conditions of the mode-locked lasers were explored. The period-doubling self-mode-locked pulses and the quasi-periodic self-mode-locked pulses in the picosecond laser were observed and analyzed, and the output characteristics of the self-mode-locked laser with straight cavity in compact structure was studied and measured. The resonant cavity was concave flat chamber, under the condition of no other clamping device, the Nd：YVO₄ crystal as a laser gain medium and Kerr medium, and the high efficiency continuous mode-locked 1 064 nm laser pulses were outputted. The Nd：YVO₄ laser crystal is 16 mm from the input mirror, and the cavity length is 90 mm. The four kinds transmittance in 1 064 nm of output mirror are 10%, 20%, 30% and 50%, respectively, meanwhile the output characteristics of the laser were analyzed in comparison with different output mirrors. By optimizing the design, when the transmittance in 1 064 nm of output mirror is 10%, the output power of the laser is 2.76 W at 8 W incident pump power, and the slope efficiency is up to 43.2%, the repetition rate of mode-locked laser is 1.43 GHz, the laser achieves a high powered and stable continuous wavelength mode-locked.