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为进一步改善大型固体激光器3倍频用薄膜的光学及损伤特性，利用不同的测试方法系统对比研究了电子束蒸发方式制备的几种紫外薄膜的光学常数、晶体结构、表面粗糙度以及弱吸收和其激光损伤特性间的相互关系。研究表明：薄膜的弱吸收和其禁带宽度共同制约了其激光损伤阈值，而薄膜因晶相结构的产生而增大的表面粗糙度对其激光损伤阈值无影响。大弱吸收的薄膜其损伤表现为非常微小的吸收点向外扩张构成的较大的破坏点，而低弱吸收的薄膜其损伤则表现为瞬间吸收引起大的损伤。“,”For further improvement of optical and laser induced damage properties of the thin films equipped on three harmonic of YAG laser system, different test methods were used to analysis the correlations between optical constant, crystalline structures, surface roughness, weak absorption and laser induced damage threshold of several thin films fabricated by reactive electron beam deposition process with different ultraviolet materials. The weak absorption and the bandgap limited the laser-induced damage threshold, rather than the surface roughness increased by the appearance of crystalline structures. Two laser damage processes were observed as that in higher weak absorption material, small damage expanded step by step when it absorbed the pulse laser energy, while in lower weak absorption material, a sudden damage occurred when the absorbed laser energy were higher enough.