AI 中文总结
本研究针对非晶硅平板X射线探测器的长期滞后现象，提出实验表征框架与多陷阱速率方程模型，解决过冲行为问题，建立了可重复的滞后研究方法。
AI 中文摘要
探测器滞后，也称为余辉，是平板X射线探测器中导致图像退化的一个来源，会产生 temporal artefacts（ temporal artefacts 译为 temporal artefacts ，即时间伪影），降低图像质量和定量准确性。本研究提出了一种稳健且可重复的实验框架，用于在受控的阶跃上升和阶跃下降曝光跃迁下表征探测器的长期滞后（从几分钟到几小时），该框架与断层扫描（ tomography ）特别相关。从带有 CsI:Ti 闪烁体的非晶硅探测器测得的跃迁曲线表现出意外行为：在阶跃上升跃迁后，探测器响应会暂时超过其最终平衡强度，而非通常预期的逐渐单调上升和衰减。这些曲线可通过多指数函数很好地拟合，为闪烁体中电荷陷阱的深度提供了初始估计。这些参数被纳入所提出的多陷阱速率方程模型中，该模型重现了观察到的阶跃上升和阶跃下降跃迁的整体行为，包括以往模型无法捕捉的过冲现象。尽管模型与观测之间仍存在差异，但本研究建立了一种可重复的探测器滞后表征方法，并提出了一种改进的物理模型，该模型能更深入地理解控制探测器滞后的机制。
英文摘要
Detector lag, also referred to as afterglow, is a source of image degradation in flat-panel x-ray detectors, producing temporal artefacts that reduce image quality and quantitative accuracy. In this work, we present a robust and repeatable experimental framework for characterising long-term detector lag (from minutes to hours) under controlled step-up and step-down exposure transitions of particular relevance to tomography. The measured transition curves from an amorphous silicon detector with a CsI:Ti scintillator exhibit unexpected behaviour, with the detector response temporarily overshooting its final equilibrium intensity following step-up transitions, rather than exhibiting the gradual monotonic rise and decay typically expected. These curves were well fitted by multi-exponential functions, providing initial estimates for the depth of the charge traps in the scintillator. These parameters were incorporated into a proposed multi-trap rate equation model that reproduces the overall observed behaviour of both step-up and step-down transitions, including the overshoot that is not captured by previous models. Although discrepancies remain between the model and observation, this work establishes a reproducible methodology for detector lag characterisation and presents an improved physical model that offers greater insight into the mechanisms governing detector lag.
Comments14 pages, 9 figures
