高稳定性阵列光栅拼接架设计与验证

Design and Demonstration of High Stability Array Tiled Grating Frame

光栅拼接是解决光栅口径限制的一种有效途径,而光栅拼接的难点是子光栅的精密调整和稳定性保持。为实现子光栅的精密调整,采用了差动螺纹和压电驱动器两级驱动调整机构,子光栅调整精度可达纳米量级;为提高光栅拼接架结构稳定性,对影响光栅拼接架结构稳定性的因素进行了理论分析,根据分析结果,设计了新型的光栅拼接架,采用整体式支撑结构以提高光栅拼接架的固有频率,用柔性铰链代替弹簧以提高子光栅与光栅支撑架的联接刚度,光栅拼接架的稳定性得到大幅提高。经实验测试,拼接架的稳定时间超过1h,子光栅间相对位移标准差为35.7nm,拼接架满足使用要求。

Tiled grating is one of effective the ways to solve the problem of grating aperture limit and the difficulties of tiled grating are the adjustment of sub-aperture grating and stability.Two classes of macro and micro drive modes are adopted to achieve the precision adjustment of sub-aperture gratings.A new tiled grating frame is designed to increase the stability of tiled grating frame.In the tiled grating frame,an integrated support structure is adopted to increase the natural frequency of the tiled grating,and flexible hinges are adopted instead of springs to increase the joint stiffness between the sub-aperture grating and the support frame.The experiment indicates that the tiled grating can keep in stability for more than one hour and the relative displacement standard deviation is 35.7 nm between sub-aperture gratings,which can satisfy the design requirement.