A novel method of coded-aperture push-broom compton scatter imaging: Principles, simulations and experiments

摘要

Compton scatter imaging (CSI) is a promising, noninvasive imaging technique; however, it is limited by its poor utilization of X-rays and its bad image signal-to-noise ratio (SNR). In this work, a novel method combining push-broom CSI with coded-aperture imaging was devised to improve the utilization of backscattered X-rays and the image SNR. Firstly, the principles of coded-aperture push-broom CSI are illustrated, and its various applications are discussed. Then, simulations of a point source and a line source are performed to validate its feasibility. It was discovered that the inherent coding noise trends for the mask and the antimask were the opposite of each other. Therefore, these coding noises could be offset by averaging the two. Furthermore, a system prototype was built to scan objects, such as point phantoms, line phantoms, character phantoms of ''IHEP'', and other typical samples. Compared with traditional push-broom CSI, this novel system obtained a better backscatter image with lower X-ray power and at a farther distance. This feature is important for system miniaturization and radiation dose reduction. Although optimizations should be considered in the future, this approach demonstrates useful application potential.