Optimal 'Tomography' of 2-Layered Targets: 3D Parameters Reconstruction from Shadow Images

A method of ICF targets parameters reconstruction from the set of backlit shadowgraph images was developed. Proposed approach can be used for nondestructive inner (DT ice in the case of cryotarget) surface quality characterization of single- and double-layered targets and shells.

Previously designed computer 3D ray-tracing model allowed us to carry out detailed investigation of the target shadowgraph image formation, to localize rays forming bright ring and to infer analytical description of this rays' group. Having been guided by this experience we designed an algorithm of inner surface shape determination using bright ring location on target's image and developed corresponding software package.

This package provides a wide set of image processing tools: both general processing (pointwise operations, spatial filtering, maximums and edges localization, etc.) and specific methods (3D reconstruction, inner and outer surfaces RMS and power spectra estimation, results' visualization in different forms, etc).

Proposed method and its software implementation were tested using two kinds of image sets - set of backlit photographs of real one-layered shells and set of digitally synthesized shadowgraph images.