COAT中有限子孔径对补偿效果的影响

Effects of finite subaperture size on COAT system

本文分析了大气湍流引起的波前位相畸变经变形镜校正后的剩余位相误差,导出了有限子孔径下的斯特列尔比及补偿效率的表达式,并讨论了不同参数对它们的影响。

We analyses beam quality and compensation efficiency in the case ol finite correct-element size by using the deformable mirror as a spatial filter. Although the StrehPs ratio increases as the subaperture size reduces, it reduces very slowly when the size is small. Based on our theories the optimal size can be easily determined for high performan-ce-to-eost ratio. In order to compare with experimental results we have introduced concept of compensation efficiency. The calculations reveal that the compensation efficiency is low for Tery weak turbulence. It increases at the beginning while turbulence becomes stonger. But it rapidly decreases after reaching the maximum ^alue. These conclusions support the preview experimental facts.