球面弯晶实现X射线单能成像的研究

Research on the monochromatic X-ray imaging with spherically bent crystal

基于Bragg衍射原理,研制了一种对激光等离子体进行二维成像的球面晶体分析器。采用球面弯曲石英晶体作为分析器,X射线IP板作为成像器件。采用Cr靶X射线辐射金属网格(目标),网格的网孔尺寸为200μm×200μm。通过球面弯晶对Cr靶Kα谱线的衍射,得到网格的二维单色衍射图像。实验结果表明,球面弯晶分析器具有较高的光谱分辨力和信噪比,谱分辨力λ/Δλ达到1 000,且具备二维成像能力;当光源尺寸为500μm时,分析器空间分辨力达到54μm。

The reflective spherically bent crystal is investigated based on the Bragg diffraction to diagnose the laser plasma X-ray.The spherically bent quartz crystal and the X-ray imaging plate are used as the X-ray analyzer and the imaging device,respectively.The imaging experiment was carried out at the X-ray diffractometer facility by using Cr target.The monochromatic image of a mesh interval of 0.2 mm×0.2 mm is obtained by the spherically bent crystal.The spherically bent crystal analyzer has high spectrum resolution and high signal-to-noise ratio,and the calculated spectrum resolution could reach 1000 in 0.2-0.4 nm.Furthermore,the spatial resolution of the spherically bent crystal analyzer is 54 when the size of the X-ray source is 500 μm.It is suitable for soft X-ray spectroscopy diagnosis.