DIRECT CONVERSION DETECTOR FOR DIGITAL FLUOROSCOPY

荧光透视是一种非常重要的动态放射成像方式 并提供有关内部结构、流动和 患者的运动。 荧光镜检查广泛用于诸如 减影血管造影，胃肠成像，心血管 成像以及其他介入放射学研究。 目前，使用图像增强器进行荧光检查研究 （XRII），其具有大视场和快速成帧能力。 然而，XRII在尺寸方面有明显的缺点， 灵活性和成本。他们也遭受着面纱眩光和显示图像- 边缘的扭曲。最后，它们具有有限的动态范围， 中度DQE。 针对这种情况，我们建议开发大面积平板， 结合高阻半导体薄膜的数字成像探测器 (of碘化铅（PbI 2）技术正在RMD开发， 格式化非晶硅（a-Si：H）读出技术， 由我们的合作者施乐帕洛阿尔托研究中心的罗伯特·斯特里特博士开发。 在这 方法，像素化PbI 2膜作为传感器产生电子-空穴 对直接在X射线相互作用，和a-Si：H读出电路 提供每个Pb 1 2像素的低噪声、真实的时间读出。整体 系统提供更宽的动态范围和更高的检测效率（比 XRII），因此可以在较低的温度下获得等效图像 次给药结束最后，可以大规模制备PbI_2薄膜和a-Si：H读出器 面积低成本，因此具有成本效益的大面积探测器（20厘米 x 20 cm），可以进行开发。第一阶段项目将集中在 证明了这种有前途的探测器概念的可行性。 拟议的商业应用： 除了大型医疗放射成像市场外， 探测器将在其他应用中得到广泛接受，例如非 破坏性测试、X射线衍射和高能物理。

Fluoroscopy is a very important modality for dynamic radiographic imaging and provides vital information about internal structure, flow and movement in a patient. Fluoroscopy is widely used in procedures such as subtraction angiography, gastro-intestinal imaging, cardiovascular imaging as well as in other interventional radiological studies. Currently fluoroscopic studies are performed using image intensifiers (XRII) which have large field of view and fast framing capabilities. However, the XRII have significant drawbacks in terms of size, flexibility and cost. They also suffer from veiling glare and show image- distortions at edges. Finally, they have limited dynamic range and moderate DQE. To address this situation, we propose to develop a large area flat panel, digital imaging detector by combining high resistivity semiconductor film (of lead iodide, Pbl2) technology being developed at RMD with the large format amorphous silicon (a-Si:H) readout technology which has been developed by our collaborator, Dr. Robert Street at Xerox PARC. In this approach, pixellated Pbl2 film acts as the sensor producing electron-hole pairs directly upon X-ray interaction, and a-Si:H readout circuitry provides low noise, real time readout of each Pbl2 pixel. The overall system provides wider dynamic range and higher detection efficiency (than XRII) and therefore offers possibility of equivalent images at lower dose. Finally, Pbl2 films and a-Si:H readout can be prepared in large areas at low cost, and hence cost effective large area detectors (20 cm x 20 cm) can be developed. The Phase l project will focus on demonstrating the feasibility of this promising detector concept. PROPOSED COMMERCIAL APPLICATIONS: Besides the large medical radiographic imaging market, the proposed detector would find wide acceptance in other applications such as non destructive testing, X-ray diffraction, and high energy physics.