Imaging of laser produced plasma at 1.43 keV using Fresnel zone plate and Bragg–Fresnel lens
Imaging of laser produced plasma at 1.43 keV using Fresnel zone plate and Bragg–Fresnel lens
复制标题
使用菲涅尔波带板和布拉格菲涅尔透镜对 1.43 keV 激光产生的等离子体进行成像
DOI：
10.1063/1.1149082
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发表时间：
1998
影响因子：
1.6
通讯作者：
J. Breton
中科院分区：
文献类型：
--
作者：
G. Cauchon;Muriel Pichet;R. Sauneuf;P. Dhez;M. Idir;M. Ollivier;P. Troussel;J. Boutin;J. Breton
由于探测器上的光通量太低，针孔无法实现分辨率为1μm量级的等离子体的X射线成像。我们测试了两种不同类型的衍射镜，它们是由基于菲涅尔区的圆形光栅衍生而来的。与针孔相比，它们的等效直径约为100μm，分辨率约为1μm。被测试的两种器件是：(1)与多层反射镜相关联的透射型菲涅耳区透镜；(2)将多层镜与光栅相结合的反射型布拉格-菲涅耳透镜。PFZL通过透射法工作在垂直入射状态；附加的反射镜只反射光谱内的一小部分带宽；设置多层成像光束在反射镜上的反射角，以调整有用带宽的中心。BFL工作在固定的掠入射下，为了避免探测器受到零级光斑的照射，我们只使用了BFL的离轴部分。
X-ray imaging of plasmas with a resolution on the order of 1 μm could not be achieved with pinholes because the light flux on the detector would be too low. We tested two different types of diffractive lenses derived from the circular grating based on the Fresnel zones. Compared to pinholes, they can have an equivalent diameter of about 100 μm with a resolution of about 1 μm. The two kinds of devices tested were: (1) a transmission phase Fresnel zone lens (PFZL) associated with a multilayer mirror; (2) a reflective Bragg–Fresnel lens (BFL) which combines a multilayer mirror and the grating. The PFZL works at normal incidence by transmission; an additional mirror is used to reflect only a small bandwidth within the spectrum; the angle of reflection of the multilayer of the imaging beam on the mirror is set as to adjust the center of the useful bandwidth. The BFL works at fixed grazing incidence and we only use an off-axis part of the BFL in order to avoid the illumination of the detector by zeroth order di...