Hejazi S, Trauernicht D P
Eastman Kodak Company, Rochester, New York 14650, USA.
Med Phys. 1997 Feb;24(2):287-97. doi: 10.1118/1.598072.
System modeling is used to investigate the effect of various system parameters on the image quality in CCD-based x-ray imaging systems. The systems considered consist of a typical phosphor-based scintillating screen coupled to a CCD through lens or fiberoptic taper. Two applications, chest radiography and mammography, are analyzed. For each application typical system characteristics and operating conditions are used to determine the detective quantum efficiency (DQE) as a function of spatial frequency, optical collection efficiency, optical demagnification factor, and electronic noise. The DQE is modeled by extending the analysis for storage phosphor systems. The calculations are done for typical exposure conditions (0.25 mR for chest and 10.0 mR for mammography); however, the exposure effects are also discussed. It was found that a reasonable DQE can be obtained for both applications through each coupling approach; however, the demagnification requirements and electronic noise limitations are more stringent for the digital mammography application.
系统建模用于研究基于电荷耦合器件（CCD）的X射线成像系统中各种系统参数对图像质量的影响。所考虑的系统由一个典型的基于磷光体的闪烁屏组成，该闪烁屏通过透镜或光纤锥耦合到CCD。分析了两种应用，即胸部X线摄影和乳腺摄影。对于每种应用，使用典型的系统特性和操作条件来确定作为空间频率、光学收集效率、光学缩小倍率因子和电子噪声函数的探测量子效率（DQE）。通过扩展对存储磷光体系统的分析来对DQE进行建模。计算是针对典型的曝光条件（胸部为0.25 mR，乳腺摄影为10.0 mR）进行的；然而，也讨论了曝光效果。结果发现，通过每种耦合方法，两种应用都可以获得合理的DQE；然而，对于数字乳腺摄影应用，缩小倍率要求和电子噪声限制更为严格。
