针对神光-Ⅲ主机激光装置片状放大器的洁净控制采取了一系列有效措施。除了设计上更有利于洁净控制外, 机械结构件表面残留不挥发性有机污染物也达到了低于1 mg/m2的水平。为了进一步提高放大器洁净度, 进行了光照清洗。实验结果表明:神光-Ⅲ主机装置的洁净水平与美国国家点火装置接近, 光照清洗时内部气溶胶等级维持在5 000~10 000之间, 且绝大部分表面有机残留物在最初几发光照清洗中已被释放, 从而得到一个干净的放大器腔体, 减少了放大器运行时光学元件受污染和损伤的几率。

A contamination control plan was introduced to improve the cleanliness of slab amplifiers for Shenguang-Ⅲ laser driver, including laser structure optimization and precision cleaning methods, and the non-volatile-residue amount on the surface of mechanical structures was lower than 1 mg/m2 after precision cleaning. The illuminating cleaning experiment by flashlamp light was introduced to further improve the facility’s cleanliness. The results indicate that the cleanliness of Shenguang-Ⅲ laser driver is close to that of NIF, but better than other similar devices in the world. The aerosol concentration in Shenguang-Ⅲ amplifier cavity during flashlamp shots maintained among 5 000 to 10 000 particles (larger than 0.5 μm) per cubic foot, and most of the surface organic residue was released at the first few shots and a clean amplifier was obtained finally. The significant improvements in cleanliness have provided a strong guarantee for the safe operation of Shenguang-Ⅲ laser driver.