Laslandes Marie, Patterson Keith, Pellegrino Sergio
Appl Opt. 2015 May 20;54(15):4937-52. doi: 10.1364/AO.54.004937.
A novel design and selection scheme for surface-parallel actuators for ultrathin, lightweight mirrors is presented. The actuation system consists of electrodes printed on a continuous layer of piezoelectric material bonded to an optical-quality substrate. The electrodes provide almost full coverage of the piezoelectric layer, in order to maximize the amount of active material that is available for actuation, and their shape is optimized to maximize the correctability and stroke of the mirror for a chosen number of independent actuators and for a dominant imperfection mode. The starting point for the design of the electrodes is the observation that the correction of a figure error that has at least two planes of mirror symmetry is optimally done with twin actuators that have the same optimized shape but are rotated through a suitable angle. Additional sets of optimized twin actuators are defined by considering the intersection between the twin actuators, and hence an arbitrarily fine actuation pattern can be generated. It is shown that this approach leads to actuator systems with better performance than simple, geometrically based actuators. Several actuator patterns to correct third-order astigmatism aberrations are presented, and an experimental demonstration of a 41-actuator mirror is also presented.
提出了一种用于超薄、轻质镜子的表面平行致动器的新颖设计和选择方案。致动系统由印刷在粘结到光学质量基板上的连续压电材料层上的电极组成。电极几乎完全覆盖压电层，以便最大限度地增加可用于致动的活性材料量，并且其形状经过优化，以针对选定数量的独立致动器和主导缺陷模式最大化镜子的可校正性和行程。电极设计的出发点是观察到，对于具有至少两个镜面对称平面的面形误差，使用具有相同优化形状但旋转适当角度的双致动器进行校正最为理想。通过考虑双致动器之间的交叉点来定义额外的优化双致动器组，因此可以生成任意精细的致动模式。结果表明，这种方法导致的致动器系统比简单的基于几何形状的致动器具有更好的性能。给出了几种用于校正三阶像散像差的致动器模式，还给出了一个41致动器镜子的实验演示。
