MMT adaptive secondary: performance evaluation and field testing
MMT adaptive secondary: performance evaluation and field testing
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MMT 自适应二级：性能评估和现场测试
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
F. Zocchi
中科院分区：
文献类型：
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作者：
G. Brusa;A. Riccardi;P. Salinari;F. Wildi;M. Lloyd;H. Martin;R. Allen;D. Fisher;Doug L. Miller;R. Biasi;D. Gallieni;F. Zocchi
用于MMT的自适应辅助（称为MMT336）是此类镜像中的第一个镜像。它的设计允许直接在副镜位置应用波前校正（包括尖端倾斜）。这种自适应光学操作选择的优点是更高的吞吐量，更低的发射率和更简单的光学设置。反射镜还具有大多数校正器所没有的功能，包括内部位置反馈，大行程（允许斩波）和提供绝对位置校准。用于MMT的336执行器自适应辅助系统已经在我们的自适应光学测试设施中每天使用了一年多，这已经建立了对镜子操作的信心，并允许我们将其连接到MMT自适应光学系统。在这里，我们展示了在实验室中获得的关于镜像性能的最新数据。通过使用干涉仪测量，我们能够获得约40nm rms的残余表面误差。将反射镜与Shack-Hartmann波前传感器耦合，我们获得了稳定的闭环操作，闭环带宽为-3dB，约为30Hz，受波前传感器帧率的限制。我们还提供了一些初步结果，显示了5Hz， 90%占空比，±5弧秒的反射镜斩波。最后简要总结了望远镜首次光自适应光学运行的经验和遇到的问题。在本次会议上提交的另一篇论文中可以找到更广泛的报告。
The adaptive secondary for the MMT (called MMT336) is the first mirror of its kind. It was designed to allow the application of wavefront corrections (including tip-tilt) directly at the secondary mirror location. Among the advantages of such a choice for adaptive optics operation are higher throughput, lower emissivity, and simpler optical setup. The mirror also has capabilities that are not found in most correctors including internal position feedback, large stroke (to allow chopping) and provision for absolute position calibration. The 336 actuator adaptive secondary for MMT has been used daily for over one year in our adaptive optics testing facility which has built confidence in the mirror operation and allowed us to interface it to the MMT adaptive optics system. Here we present the most recent data acquired in the lab on the mirror performance. By using interferometer measurements we were able to achieve a residual surface error of approximately 40nm rms. Coupling the mirror with a Shack-Hartmann wavefront sensor we obtained a stable closed loop operation with a -3dB closed loop bandwidth of approximately 30Hz limited by the wavefront sensor frame rate. We also present some preliminary results that show a 5Hz, 90% duty cycle, ±5 arcsec chopping of the mirror. Finally the experience gained and the problems encountered during the first light adaptive optics run at the telescope will be briefly summarized. A more extensive report can be found in another paper also presented at this conference.