摘要
离子束抛光技术的关键在于对驻留时间进行求解,通常通过反卷积运算来完成。这在理论上可以实现,但是当需要加工量很小或趋于零时,加工时间就变为无穷大,此时变成一个病态问题。因此驻留时间的求解变得困难,出现的奇异值使加工难以实现。以Clean算法为基础提出了天文望远镜离子束抛光技术中对驻留时间求解的一种新的有效方法,并通过拟合来处理数据,理论上可以实现任何精度。更好地方便计算机控制的实现,为加工提供了基础。仿真结果表明,此方法所求驻留时间符合天文光学镜面离子束抛光技术的要求。
To solve the dwell time is the key step in the ion-beam figuring. Usually, the solution is derived through deconvolution. Such a solution is achieveable in principle. Nevertheless, when tiny （or even no） amount is to be polished away, the so-derived time becomes infinite. The deconvolution thus becomes illdefined, so that it is difficult to determine the dwell time. The figuring cannot continue if such singular values appear. Based on the Clean algorithm, we discuss a new method to solve the dwell time in the ion-beam figuring of mirrors for astronomical telescopes. By fitting the data of mirror any precision of the solution of dwell time can be achieved with the new method. The method is also convenient for computer controlling in the figuring with ion beam. Certain simulation results demonstrate that the solutions of the new method can meet the practical need of such mirror figuring.
出处
《天文研究与技术》
CSCD
2009年第2期124-129,共6页
Astronomical Research & Technology
