Comprehensive simulation and analysis of lobster eye micro-pore optics imaging in the hard X-ray band

Abstract

The lobster eye lens uses square channels to reflect and converge light. It has no fixed optical axis and possesses advantages such as a broad field of view (FOV) and no chromatic aberration. Moreover, lobster eye lenses based on microporous optics manufacturing technology have been successfully applied to the spatial detection of soft X-ray spectra. Based on the penetrability of hard X-rays, lobster eye lenses can detect the perspective of hidden targets, which can be applied to fields such as safety inspection and industrial flaw detection. This study proposes an algorithm for comprehensive analysis of the imaging ability of a hard X-ray lobster eye lens, focusing on the stray rays transmitted by high-penetration X-rays. The simulation results showed that the point-spread function of the off-axis FOV is different. With the increase in the photon energy, the enhanced superposition effect of the cross-arm decreases the image contrast. Both the simulated and experimental images show that the image contrast decreases as the photon energy increases. The image contrast can be improved by adding more Pb to the materials used to create the lobster eye lens owing to the strong attenuation ability of Pb to X-rays. These results can contribute to the improvement of lobster eye lenses in X-ray backscatter imaging.