A focusing spectrometer with toroidally bent crystal is designed for X-ray monochromatic imaging. The focusing properties of toroidally bent crystal and spherically bent crystal in Bragg geometry are discussed, and the conditions for optimized two-dimensional(2D) imaging of X-ray source are proposed. X-ray backlight imaging experiments have been carried out in Research Center of Laser Fusion. A toroidally bent crystal of mica was used as the imaging element with curvature radii of 290 mm and 190 mm in meridional and sagittal planes, respectively. With the high collection efficiency of the bent crystal spectrometer, high quality visible 2D X-ray backlighting images were obtained by the imaging plate. It is demonstrated that, the toroidally bent mica crystal can be used for X-ray monochromatic backlight imaging. The analysis of the spectral information in sagittal direction shows that, the toroidally bent crystal spectrometer has a spatial resolution about 100 um, which meets the design requirement.%设计了可用于X射线成像用的聚焦型超环面晶体谱仪,讨论了基于布拉格几何结构的超环面及球面弯曲晶体聚焦特性,给出了基于超环面晶体X射线2维单能成像的光源、晶体及探测器的最佳位置,在中国工程物理研究院激光聚变研究中心进行了X射线背光成像实验.利用超环面弯曲晶体作为成像器件,其弧矢及子午平面的曲率半径分别为290 mm及190 mm,该曲面晶体具有极高的聚光效率.实验中利用X射线成像板获取了Cr的Kα射线辐射形成的金属栅格2维图像.实验结果表明,研制的超环面晶体能够用于X射线单能成像；分析图像的光谱信息可知,在弧矢方向的空间分辨力约为100tm,实验结论符合预期目标.
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