“天光”一号MOPA系统光学元件加工与镀膜的进展

本文阐述了在中国原子能科学研究院“天光一号”ＫｒＦ激光核聚变实验装置上，ＭＯＰＡ系统光学元件加工与镀膜研究工作的进展。实验测量结果表明，加工后的基片表面均方根粗糙度对于Ｋ９光学玻璃与熔融石英玻璃来说分别为σｒｍｓ＝１．８±０．５ｎｍ，σｒｍｓ＝２．０±０．４ｎｍ。镀ＨｆＯ２／ＳｉＯ２高反射膜的光学元件的反射率与破坏阈值分别为Ｒ＞９９．５％，Ｅｔｈ＝１．３０～１．３３Ｊ／ｃｍ２。镀Ａｌ２Ｏ３／ＭｇＦ２增透膜的光学元件的透射率与破坏阈值分别为Ｔ＞９９．５％，Ｅｔｈ＝１．３～１．９７Ｊ／ｃｍ２。

Progress in optical coatings for heaven Ⅰ MOPA system

The improvement in the performances of UV dielectric optical coating used in the Heaven Ⅰ facility has been achieved. The root mean square roughness of the substrates of fused silica and K9 optical glass are σ rms =2.0±0.4nm and σ rms =1.8±0.5nm, respectively. The transmittance of the anti reflection coatings and the reflection coefficient of the high reflector are all larger than 99.5%. The damage thresholds of the AR coatings and HR are 1.96J/cm 2 and 1.33J/cm 2,respectively. The pulse width and the wavelength of the irradiation KrF laser are 25 ns and 248 nm.