Adaptive Optics on Large Telescopes
Adaptive Optics on Large Telescopes
复制标题
大型望远镜上的自适应光学器件
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
W. Hackenberg
中科院分区：
文献类型：
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作者：
A. Glindemann;S. Hippler;T. Berkefeld;W. Hackenberg
地面望远镜的观测会受到大气湍流的影响。与望远镜的大小无关，可见光中的角分辨率相当于直径为10-20厘米的望远镜。这种效应是由大气中不同温度空气的湍流混合造成的。因此，恒星在无穷远处发出的完美平面波在进入望远镜之前会发生像差。在下文中，我们将讨论通过湍流成像的物理背景，使用Kolmogorov统计，以及不同的技术来感知和校正波前像差的自适应光学。讨论了自适应光学系统对控制回路的要求，包括作为波前传感方法的函数的导星极限星等的公式、波前传感器相机的质量和校正度的公式。最后，简要介绍了变形镜技术，并提出了一种测量和区分单个湍流层以增大等晕角的新方法。
Observations withground based telescopes suffer from atmospheric turbulence.Independent of the telescope size the angular resolution inthe visible is equivalent to that of a telescope with adiameter of 10–20 cm. This effect is caused by the turbulentmixing of air with different temperatures in the atmosphere.Thus, the perfect plane wave from a star at infinity isaberrated before it enters the telescope. In the following,we will discuss the physical background of imaging throughturbulence, using Kolmogorov statistics, and the differenttechniques to sense and to correct the wave-front aberrationswith adaptive optics. The requirements for the control loop ofan adaptive optics system are discussed including formulas forthe limiting magnitude of the guide star as a function of thewave-front sensing method, of the quality of the wave-frontsensor camera, and of the degree of correction. Finally, ashort introduction to deformable mirror technology will begiven followed by the presentation of a new method to measureand to distinguish individual turbulent layers in order toincrease the isoplanatic angle.