Component analysis of a new Solid State X-ray Image Intensifier (SSXII) using photon transfer and Instrumentation Noise Equivalent Exposure (INEE) measurements.
Component analysis of a new Solid State X-ray Image Intensifier (SSXII) using photon transfer and Instrumentation Noise Equivalent Exposure (INEE) measurements.
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DOI：
10.1117/12.813957
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发表时间：
2009-01-01
期刊：
影响因子：
--
通讯作者：
Rudin S
中科院分区：
文献类型：
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作者：
Kuhls-Gilcrist A;Bednarek DR;Rudin S
SSXII是一种新型x射线成像仪，旨在改善传统动态x射线/荧光成像仪在分辨率、电荷捕获、帧率和仪器噪声方面的性能限制。SSXII由CsI:Tl荧光粉通过光纤锥（FOT）耦合到电子倍增CCD （EMCCD）组成。为了便于调查研究，最初的设计使这些成像组件具有互换性。各种组件和配置特性的测量能够对探测器的整体性能进行优化分析。利用光子转移表征EMCCD的ADC灵敏度、读噪声、全阱容量和量子效率。采用RQA x射线光谱测量x射线灵敏度。对成像元件的MTF和传输效率进行了分析。经测量，EMCCD在适当的EMCCD增益下具有非常低的有效读取噪声，小于1电子有效值，比平板（FPD）和基于cmos的探测器低两个数量级。可变信号放大从1到2000倍使可选择的灵敏度范围从8.5（168）到超过15k （300k）电子每个入射x射线光子与（不）4:1 FOT；这些灵敏度可以很容易地增加进一步的成分优化。MTF和DQE测量表明，SSXII在低空间频率下的性能与当前最先进的探测器相当，在高空间频率下则远远超过它们。在10 cycles/mm范围内，仪器噪声等效暴露（INEE）小于0.3 μR，明显优于FPDs。成分分析表明，这些改进可以大大增加进一步的探测器优化。
The SSXII is a novel x-ray imager designed to improve upon the performance limitations of conventional dynamic radiographic/fluoroscopic imagers related to resolution, charge-trapping, frame-rate, and instrumentation-noise. The SSXII consists of a CsI:Tl phosphor coupled via a fiber-optic taper (FOT) to an electron-multiplying CCD (EMCCD). To facilitate investigational studies, initial designs enable interchangeability of such imaging components. Measurements of various component and configuration characteristics enable an optimization analysis with respect to overall detector performance. Photon transfer was used to characterize the EMCCD performance including ADC sensitivity, read-noise, full-well capacity and quantum efficiency. X-ray sensitivity was measured using RQA x-ray spectra. Imaging components were analyzed in terms of their MTF and transmission efficiency. The EMCCD was measured to have a very low effective read-noise of less than 1 electron rms at modest EMCCD gains, which is more than two orders-of-magnitude less than flat panel (FPD) and CMOS-based detectors. The variable signal amplification from 1 to 2000 times enables selectable sensitivities ranging from 8.5 (168) to over 15k (300k) electrons per incident x-ray photon with (without) a 4:1 FOT; these sensitivities could be readily increased with further component optimization. MTF and DQE measurements indicate the SSXII performance is comparable to current state-of-the-art detectors at low spatial frequencies and far exceeds them at higher spatial frequencies. The instrumentation noise equivalent exposure (INEE) was measured to be less than 0.3 μR out to 10 cycles/mm, which is substantially better than FPDs. Component analysis suggests that these improvements can be substantially increased with further detector optimization.