Staring X-ray backscatter imaging based on ultra-high aspect ratio lobster eye lens

Abstract

In contrast to conventional X-ray imaging systems, the lobster eye lens, serving as a pivotal component for X-ray focusing, presents the potential for downsizing X-ray backscatter imaging systems. This study reports the successful implementation of a pioneering non-contact staring X-ray backscatter imaging experiment, with the target positioned 1.5 meters away from the system and employing a tube voltage of 60 kV for the X-ray light source. The system is built upon a novel high aspect ratio (500) meridian lobster eye lens, employing a laboratory low illuminance desktop light source and a commercial X-ray detector to achieve high-resolution focused imaging of hard X-rays. Point spread function testing and a series of imaging experiments were carried out to assess the resolution and optimal imaging photon energy of the proposed system. Furthermore, according to the characteristics of the point spread function of the cross image of the lobster eye lens, we proposed an image processing algorithm. The experimental results demonstrate that, after processing, the Structural Similarity (SSIM) Index of the backscatter image and the ground truth image can be improved from an average of 0.0526 to 0.5758. Our research significantly contributes to the advancement of a new generation of X-ray backscatter imaging systems.