高分辨率光谱仪与极大望远镜耦合问题分析

介绍国际上地面极大光学/红外望远镜的研制概况，分析高分辨率光谱仪与极大口径望远镜耦合中的难题，结果表明极大口径望远镜需要超大面积阶梯光栅和超快焦比相机。根据光谱仪与望远镜的匹配关系，30 m级极大口径望远镜的高分辨率光谱仪的准直光束将大于70 cm，主色散阶梯光栅的面积大于2 m2，照相机的焦比F/0.5，按照目前的制造技术无法提供上述光栅和相机，因此，提出高分辨率光谱仪与极大望远镜进行耦合的技术。针对耦合问题给出了相应解决方案，即采用像切分器、拼接光栅以及白瞳设计等技术将是极大口径望远镜与高分辨率光谱仪耦合的主要解决方案。

Technique challenges in coupling of high resolution spectrograph with extremely large telescope

We reviewed the designing of several international ground-based extremely large optical/infrared telescopes and introduced the problems faced in the coupling of high resolution spectrograph with telescopes of extremely large aperture. It is proposed that large area of echelle and ultrafast focal ratio camera can serve as a solution. According to the coupling rule of the spectrogragh and the telescope, the diameter of collimated beam for a 30 m telescope would be over 70 cm, and the size of the main dispersion echelle grating would be larger than 2 m2. To build such huge and costly equipment would be difficult with current techniques. And large aperture camera with focal ratio F/0.5 is also hard to design and manufacture. Image slicer, mosaic gratings and white pupil optic become major solutions in designing the high resolution spectrograph for an extremely large aperture telescope.