Φ1m平面镜的力学分析及实验研究

空间太阳望远镜(SST)的装校需要一个倒置的直径为1m的平面镜,此平面镜的面形精度决定了SST的装校成败。平面镜的支撑采用滑轮砝码机构,具有18个牵引点,每个牵引点的牵引力是独立可调的。在此支撑下,利用有限元分析方法分析了平面镜的变形情况,提出了用主动光学原理对牵引力大小进行优化的方法,计算出了保持平面镜具有良好面形时所需要的牵引力的大小。采用Ritchey_Common方法对平面镜进行了测量。测量结果表明,平面镜面形精度的均方根值优于λ/30(λ=633nm),满足了SST的装校要求。

Mechanical analysis and experiment study of the Φ1m flat mirror

An inverted Φ1m flat mirror was needed in alignment of space solar telescope (SST), the precision of face shape determined the success and failure of SST's alignment. The support of the mirror was conducted to 18 dragging points by a mechanism with pulleys and poises, and the pull of each dragging point could be adjusted independently. The support structure of the flat mirror was introduced, and the distortion caused by gravity was analyzed through finite element method, the method of optimizing pull magnitude was proposed using active optical principle to figure out the pull value needed to keep the adequate shape of the mirror. The tests were processed by Ritchey_Common method. The results show that the root_mean_square of precision of that mirror face shape is superior to λ/30 (λ=633nm) to arrive the demands of SST's alignment.