针对高平均功率固体激光器对Nd:YAG晶体板条的技术需求,进行了Nd:YAG晶体板条低透射波前误差加工技术研究.详细分析了光学加工过程中引起板条端面透射波前畸变的误差来源,并提出工艺技术解决方案.实验结果表明,在板条抛光阶段通过采用合成盘硬抛光工艺以及新的工件装夹技术,能够解决传统板条加工工艺在面形及楔角精度方面可控性差的问题,更容易实现Nd:YAG晶体板条的低透射波前误差加工.对于150 mm×30 mm×2.5 mm规格的Nd:YAG晶体板条元件,端面透射波前畸变PV值达到0.74λ.

The transmitted wave front aberration is the key factor which restricts the further development of high average power solid-state lasers.This work analyses the error source of transmitted wave front for end surface,and a scheme of slab processing is purposed according to technology requirement of Nd:YAG crystal slab for high average power solid-state lasers.With the new type complex pad,fixture of slab and new polishing process,the problem of poor controllability of surface figure and wedge angle in continuous polishing has been solved.The processing results show that the PV of end surface transmitted wavefront aberration reached 0.74λ for 150 mm×30 mm×2.5 mm specification Nd:YAG crystal slab.The processing precision satisfies the application requirement of high average power solid-state lasers.