In spectral diagnostic physics experiments of inertial confinement fusion, the spectral signal is weak due to the low diffraction efficiency when using bent crystals. A spectral diagnostic instrument with high efficiency and wide spectral range is urgently needed. A multi-curvature bent crystal with multi-energy focusing ability is proposed based on the traditional conical crystal geometry. It has advantages of wide spectral range, strong focusing ability, and high spectral resolution. It also can eliminate the imaging aberration in principle due to rotational symmetry for the incoming X rays. A spectral diagnostic experiment based on a fabricated multi-curvature α-quartz crystal was accomplished using a titanium X-ray tube of the bent crystal, and the corresponding experimental data using a plane α-quartz crystal was also acquired to demonstrate the strong focusing ability. The result shows that the Kα intensity of the multi-curvature α-quartz crystal is 157 times greater than that of the plane crystal, and the corresponding energy range is about 4.51–5.14 keV. This diagnostic instrument could be combined with a streak camera at a vertical direction so as to intensify the diffracted X-ray signal with a wide spectral range.

在惯性约束聚变光谱诊断物理实验研究中，晶体衍射后X射线光谱信号较弱，需要高收光效率及宽频谱范围的光谱诊断仪器.在传统锥面弯曲晶体基础上提出变曲率弯晶多能点成像技术，该技术具有宽频谱范围、强聚焦能力、高光谱分辨的特点.在晶体衍射成像结构设计中，由于能够确保成像光线的旋转对称性，因此在原理上可消除传统弯晶X射线衍射成像像差.利用研制的变曲率面石英晶体对钛靶X射线源进行X射线聚焦检测，并与同种材料的平面晶体进行收光效率对比，实验结果表明该变曲率面石英晶体的收光效率可以达到平面石英晶体的100倍，检测X射线能量范围为4.51~5.14 keV.该晶体谱仪结合X射线条纹相机能够检测宽频谱范围的微弱X射线信号，条纹相机探测面可与晶体检测光路方向垂直布局.