Simulation and experimental research of x-ray toroidally bent crystal imaging with laser-produced plasma

Based on the Bragg law and imaging principle of bent crystal, the imaging properties of the monochromic backlighting system with a toroidally bent crystal were studied via ray-tracing simulations and experiments. Comparison experiments with both toroidally and spherically bent crystals using a Cr line as the backlighter were performed, showing that using toroidally bent crystal, a 2D image with the same magnifications in meridional and sagittal directions can be obtained with higher spatial resolution. Experiments with laser-produced plasmas using Mica crystal were carried out on the Shenguang II laser facility. Five laser beams were focused onto a Ti planar target producing a line at 4.75 keV as the backlighter and an image of a metal grid with size of 200 μm × 200 μm was recorded with an x-ray image plate. A spatial resolution of 40 μm was demonstrated with a magnification of 3 due to the restriction of the target chamber size. 10 μm spatial resolution might be possible if the detector can be located outside the chamber to enlarge the magnification.