为满足激光加工、激光彩色显示、数据存储、医疗卫生和科研等领域对绿光激光器的需要,研制了一台高倍频效率、窄脉宽侧面泵浦腔外倍频的YAG／LBO绿光激光器。分析并计算了腔外最佳聚焦参数,确定了透镜的最佳聚焦焦距。实验中,利用808 nm激光二极管侧面泵浦Nd:YAG晶体,使用BBO晶体进行加压式调Q,采用四分之一波片补偿Nd:YAG晶体的热退偏,最终实现了重复频率1 kHz、输出功率10.7 W的1 064 nm输出,最大单脉冲能量为10.7 mJ。在此基础上,采用Ⅰ类温度相位匹配LBO晶体对基频光进行腔外倍频,获得了重复频率1 kHz、脉宽21 ns、最大输出功率6.04 W的532 nm准连续绿光输出,倍频效率高达59.3％。

To meet the demand in the fields of laser color display, laser processing, optical data storage, laser medical and scientific research, an efficient narrow pulse width diode-side-pumped extra-cavity-doubled green Nd:YAG／LBO laser has been developed successfully. We have analyzed and calculated the best focus parameters, and determined the best focal length of the lens. In our experiment, fundamental frequency output at 1 064 nm with average power 10.7 W and single pulse energy 10.7 mJ at repetition rate of 1 kHz are obtained, by using LD side-pumping technology and electro-optic Q-swith technology. In order to compensate for thermal depolarization, we added a quarter-wave plate in the cavity. On the basis of this, we do the exta-cavity-doubled experiment, usingⅠ-type temperature phase matched LBO crystal, which get a 6.04 W green light output. The pulse-width is 21 ns at repetition rate of 1 kHz. The optical frequency conversion efficiency from IR to green laser is up to 59.3％.