X-ray fluorescence (XRF) tomography is an emerging imaging technology with the potential for high spatial resolution molecular imaging. One of the key limitations is the background noise due to Compton scattering since it degrades the signal and limits the sensitivity. In this Letter, we present a linear focused anti-scatter grid that reduces the Compton scattering background. An anti-scatter grid was manufactured and evaluated both experimentally and theoretically with Monte Carlo simulations. The measurements showed a 31% increase in signal-to-background ratio, and simulations of an improved grid showed that this can easily be extended up to $>75\%$. Simulated tomographies using the improved grid show a large improvement in reconstruction quality. The anti-scatter grid will be important for in vivo XRF tomography since the background reduction allows for faster scan times, lower doses, and lower nanoparticle concentrations.

中文翻译：

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聚焦防散射网格，可减少X射线荧光层析成像的背景

X射线荧光（XRF）层析成像是一种新兴的成像技术，具有进行高空间分辨率分子成像的潜力。关键限制之一是由于康普顿散射引起的背景噪声，因为它会降低信号质量并限制灵敏度。在这封信中，我们介绍了一种线性聚焦的防散射网格，可减少康普顿散射本底。制作了一个防散射网格，并通过蒙特卡洛模拟进行了实验和理论上的评估。测量显示信噪比增加了31％，对改进的网格的仿真表明，可以轻松扩展到$>75％$。使用改进的网格进行的层析X射线断层扫描显示重建质量有了很大的提高。防散射网格对于体内XRF断层扫描非常重要，因为减少背景量可以缩短扫描时间，降低剂量和降低纳米颗粒的浓度。