高重频三向侧面泵浦DPL耦合系统设计

Design of coupling system in the three direction side pumped high repetition rate DPL

激光二极管侧面泵浦容易将大功率二极管阵列(LDA)光耦合到激光晶体中去,但耦合效率有待于进一步的提高。在已建立的二极管单bar侧面泵浦YAG晶体泵浦光场分布数值模型的基础上,进一步分析了三向侧面泵浦激光器晶体内光强的分布,并全面考虑了耦合系统相关的因素,结合实际设计出LD三向侧面泵浦耦合光学系统,最终获得了重复频率1～1 000 Hz可调,波长1.064μm的TEM00模的调Q窄脉冲激光输出。激光输出最大单脉冲能量为11.5 mJ,脉冲宽度为8 ns,光-光转换效率为11.7%。实验验证了该耦合系统的合理性与优越性,为高效耦合系统的进一步优化奠定了基础。

Efficiency of high power LDA coupling into laser crystal was low in the side-pumped laser.According to the analysis of light distribution in three-direction side-pumped Nd:YAG rod which based on numerical simulation of pumping light distribution in a diode bar pumped laser rod,coupling system was designed.Finally,the Q-switched pulse laser output with 1～1 000 Hz repeated-frequency,1 064 nm wavelength and TEM00 mode is obtained.The maximum single pulse energy is 11.5 mJ,impulse width is 8 ns,and 'light-to-light' conversion efficiency is 11.7%.The reasonableness of coupling system was proved by the result of experiment which bases for coupling system optimization.