平行式Schmidt型龙虾眼X射线光学系统研究

Study on lobster-eye X-ray optical system based on parallel Schmidt geometry

龙虾眼X射线系统是实现大视场X射线成像的有效手段。现研制了由多组平行玻璃平板构成的Schmidt型X射线龙虾眼光学系统,开展了X射线聚焦和成像的演示实验。基于掠入射反射理论,以210μm厚的超光滑平板玻璃作为光学元件,通过堆叠的方式制作了放大倍数为1的演示系统。用8keV的X射线光源对系统进行了聚焦和实验,直径280μm的光源聚焦半高宽约为320μm,与理论模拟结果基本一致。利用X射线背光照明,得到2mm×2mm大小图样的成像。实验结果表明,该龙虾眼光学系统可以在几毫米视场下达到百微米分辨。

Lobster-eye X-Ray system is an effective method to achieve X-ray imaging with a large field of view.A lobster-eye X-ray optical system is designed based on Schmidt geometry using parallel glass plate and X-ray focusing and imaging demonstration experiment is carried out.Based on the principle of grazing incidence reflection,a demonstration system with a unit magnification was made through stacking the flat thin glasses of 210 μm with ultra-smooth surface.Experiment of X-ray focusing was carried out using 8 keV X-ray source and a pinhole with diameter of about 280 μm.A full-width at half-maximum of about 320 μm was achieved which is almost the same with the ray tracing result.Then,the imaging ability of the system was also tested using a pattern of about 2 mm×2 mm through X-ray backlighting.The results show that this lobster-eye system can get a resolution of hundred microns under the FOV of a few millimeters.