整体X光透镜性能实验研究

Experimental Investigation of Properties of Polycapillary X-Ray Lens

利用高计数率探测器和低功率光源,在大的能量范围内,同时测量了整体X光透镜的传输效率和焦斑直径与能量的关系。实验结果表明:透镜的焦斑直径随着能量的升高而减小;对04-5-10-5透镜而言,在高于5.8keV的能量范围内,透镜的传输效率随着能量的升高而降低,在低于5.8 keV的能量范围内,透镜的传输效率随着能量的升高而增加。通过测量不同能量的X射线在透镜会聚光束中的空间分布,研究了短出口焦距透镜的光晕现象,光晕会导致透镜焦斑直径增大和传输效率测量值的增加。利用轴向扫描法研究了整体X光透镜出口焦距和能量的关系,实验结果表明:会聚透镜的出口焦距随着X射线能量的升高而增加。

Low power X-ray source and high count rate detector system are used to measure the space distribution of X-rays with different energies in the beam focused by the monolithic polycapillary X-ray lens, and the energy dependence of the focal spot size and transmission efficiency of the lens. The ＂halo＂ phenomenon can result in the increase of focal spot size and the measured transmission efficiency with higher energies. The focal spot size decreases with the increase of the energies. The transmission efficiency of the 04-5-10-5 lens increases with higher energies below about 5.8 keV and decreases with higher energies above about 5.8 keV. The axial scanning method is devised to find the energy function of the output focal distance. The output focal distance of the lens increases with the increase of the energies.