Meyer O, Burrell K H, Chavez J A, Kaplan D H, Chrystal C, Pablant N A, Solomon W M
Euratom-CEA Association, DSM-IRFM, Cadarache, France.
Rev Sci Instrum. 2011 Feb;82(2):023114. doi: 10.1063/1.3553394.
Charge exchange spectroscopy is one of the standard plasma diagnostic techniques used in tokamak research to determine ion temperature, rotation speed, particle density, and radial electric field. Configuring a charge coupled device (CCD) camera to serve as a detector in such a system requires a trade-off between the competing desires to detect light from as many independent spatial views as possible while still obtaining the best possible time resolution. High time resolution is essential, for example, for studying transient phenomena such as edge localized modes. By installing a mask in front of a camera with a 1024 × 1024 pixel CCD chip, we are able to acquire spectra from eight separate views while still achieving a minimum time resolution of 0.2 ms. The mask separates the light from the eight spectra, preventing spatial and temporal cross talk. A key part of the design was devising a compact translation stage which attaches to the front of the camera and allows adjustment of the position of the mask openings relative to the CCD surface. The stage is thin enough to fit into the restricted space between the CCD camera and the spectrometer endplate.
电荷交换光谱法是托卡马克研究中用于确定离子温度、旋转速度、粒子密度和径向电场的标准等离子体诊断技术之一。在这样的系统中配置电荷耦合器件（CCD）相机作为探测器，需要在尽可能从多个独立空间视角检测光的同时，仍要获得最佳时间分辨率这两个相互矛盾的需求之间进行权衡。例如，对于研究诸如边缘局域模等瞬态现象而言，高时间分辨率至关重要。通过在具有1024×1024像素CCD芯片的相机前安装一个掩膜，我们能够从八个不同视角获取光谱，同时仍能实现最低0.2毫秒的时间分辨率。该掩膜将来自八个光谱的光分离，防止空间和时间串扰。设计的一个关键部分是设计一个紧凑的平移台，它连接到相机前端，并允许调整掩膜开口相对于CCD表面的位置。该平移台足够薄，能够安装到CCD相机和光谱仪端板之间的有限空间内。
