设计了一种简单有效的折叠腔，采用具有部分透过率的平面反射镜作为谐振腔的腔镜，实现了激光的单路输出，提高了激光器输出的利用率，增强了激光器的实用性。利用计算机编程分析了谐振腔内元件的参数对腔内光斑分布的影响。利用自聚焦透镜对激光二极管(LD)进行整形，实现了端面抽运Nd:YVO4半导体可饱和吸收镜(SESAM)连续波锁模稳定运转。在抽运功率为3 W时，获得了平均功率为800 mW，脉冲宽度为5.2 ps的锁模脉冲，光光转换效率为27%。

With a semiconductor saturable absorber mirror (SESAM), a simple folded cavity has been designed to achieve mode-locking with a single output. The plane mirror is employed as a cavity mirror as well as an output coupler. The grin lens is employed as the optical coupler to shape the single diode laser, the stable continuous wave mode locking is achieved with the pulse width of 5.2 ps and the repetition rate of 100 MHz. The average output power is 800 mW with the pump power of 3 W, and the optical-optical conversion efficiency is 27%. The characteristics of the laser cavity are analyzed by computer.