惯性约束聚变实验中的层析成像技术研究

Tomographic techniques in inertial confinement fusion

文章对惯性约束聚变 (ICF)中的多方位成像的层析技术 (CT)和编码成像技术在激光等离子体实验中的应用进行了研究 .作者完成了以下工作 :建立了多方位层析成像系统 ,自行编制三维图像重建的软件 ;采用三个方位的针孔相机对爆推爆靶内爆压缩过程进行成像 ,同时成功地获得了三个针孔图像 ,得到的直径压缩比约为 3,且压缩的对称性很好 ;采用编码成像技术 ,在“神光Ⅱ”上成功地验证了菲涅耳波带片的可行性应用 ,并建立了激光热核聚变产生的α粒子和腔靶超热电子的菲涅耳波带片成像系统 ,获得了热核反应区的α粒子图像 ,并首次得到了厚壁腔靶的超热X射线图像 .

Computer tomography (CT) and coded imaging (CI) techniques have been applied to inertial confinement fusion . A CT system using 3-5 viewing direction pinholes has been built, and a three dimensional reconstructing code written. Three pinholes in different viewing directions were used to image the laser driven explosion push target, and three pinhole images successfully obtained in one shot. The radius compression ratio derived from the images was about 3, the compression symmetry was very good, and the three dimensional image of the capsule was reconstructed. Coded imaging applied to the Shenguang Ⅱ laser facility demonstrated the successful use of Fresnel zone plates (FZPs) in the imaging of α particles produced by hot electrons and of hot X-rays emitted from inside the Holhraum wall.