Signal, noise power spectrum, and detective quantum efficiency of indirect-detection flat-panel imagers for diagnostic radiology
Signal, noise power spectrum, and detective quantum efficiency of indirect-detection flat-panel imagers for diagnostic radiology
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DOI：
10.1118/1.598243
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发表时间：
1998-05-01
期刊：
影响因子：
3.8
通讯作者：
Cunningham, IA
中科院分区：
文献类型：
--
作者：
Siewerdsen, JH;Antonuk, LE;Cunningham, IA
间接检测，有源矩阵平板成像仪（FPI）在诊断能量的性能报告的测量和理论信号大小，噪声功率谱（SNR），和检测量子效率（DQE）。基于1536 × 1920像素，127 μ m间距阵列的a-Si：H薄膜晶体管和光电二极管，F1？我是作为一个原型开发的检查的潜力，平板技术在诊断x射线成像。每单位曝光的信号大小（X射线灵敏度）是针对FPI测量的，该FPI结合了五个市售的Gd 2 O2 S：Tb转换屏，能量为70-120 kVp。一维和二维的反射率和DQE进行了测量的FPI纳入三个这样的转换器，并作为一个函数的入射曝光。这些测量结果支持FPI在诊断放射学中具有重要应用潜力的假设。一个级联系统模型，已显示出良好的协议与测量的单个像素的信号和噪声特性的描述各种FPI设计和配置下的各种诊断成像条件下的性能。理论的X射线灵敏度，ESTA，和DQE的经验结果相比，在每种情况下，观察到良好的一致性。该模型用于描述FPI的潜在性能，该FPI包含最近开发的增强阵列，该阵列已上市，并已提议用于诊断X线摄影和荧光透视的测试和应用。在对应于胸部X线摄影的条件下，分析表明，此类系统可能达到甚至超过现有技术的DQE性能，例如屏-片和存储荧光体系统;然而，在对应于一般荧光透视的条件下，每帧的典型曝光量使得DQE受到总系统增益和附加电子噪声的限制。级联系统的分析提供了一个有价值的手段，确定成像系统的限制阶段，系统优化的工具，并为各种成像应用的FPI设计的发展战略的指导。(C)1998年美国医学物理学家协会。
The performance of an indirect-detection, active matrix flat-panel imager (FPI) at diagnostic energies is reported in terms of measured and theoretical signal size, noise power spectrum (NPS), and detective quantum efficiency (DQE). Based upon a 1536 x 1920 pixel, 127 mu m pitch array of a-Si:H thin-film transistors and photodiodes, the Fl?I was developed as a prototype for examination of the potential of flat-panel technology in diagnostic x-ray imaging. The signal size per unit exposure (x-ray sensitivity) was measured for the FPI incorporating five commercially available Gd2O2S:Tb converting screens at energies 70-120 kVp. One-dimensional and two-dimensional NPS and DQE were measured for the FPI incorporating three such converters and as a function of the incident exposure. The measurements support the hypothesis that FPIs have significant potential for application in diagnostic radiology. A cascaded systems model that has shown good agreement with measured individual pixel signal and noise properties is employed to describe the performance of various FPI designs and configurations under a variety of diagnostic imaging conditions. Theoretical x-ray sensitivity; NPS, and DQE are compared to empirical results, and good agreement is observed in each case. The model is used to describe the potential performance of FPIs incorporating a recently developed, enhanced array that is commercially available and has been proposed for testing and application in diagnostic radiography and fluoroscopy. Under conditions corresponding to chest radiography, the analysis suggests that such systems can potentially meet or even exceed the DQE performance of existing technology, such as screen-film and storage phosphor systems; however, under conditions corresponding to general fluoroscopy, the typical exposure per frame is such that the DQE is limited by the total system gain and additive electronic noise. The cascaded systems analysis provides a valuable means of identifying the limiting stages of the imaging system, a tool for system optimization, and a guide for developing strategies of FPI design for various imaging applications. (C) 1998 American Association of Physicists in Medicine.