An Advanced Technology Flat-Panel Imager for Fluoroscopy

描述（由申请人提供）：有源矩阵平板成像仪 (AMFPIs) 自大约 14 年前最初构思以来已经经历了广泛的研究和开发。由于这些努力，这种 X 射线成像技术目前已被引入各种临床环境。虽然诊断 AMFPI 比旧的传统设备具有明显的优势，但目前的间接和直接 AMFPI 技术存在固有的局限性，严重限制了它们在透视检查中常见的低曝光条件下的性能。 具体而言，与系统增益相比，现有的 AMFPI 器件存在相对较大的附加噪声。导致该提案的研究特别确定了两种创新策略，它们显示出消除这些限制的特别希望。因此，拟议研究中要探讨的问题是：“通过开发和结合成像仪设计的具体基础创新，开发大面积、先进技术、荧光镜 AMFPI 是否可行，其性能水平在所有条件下都与 X 射线图像增强器相匹配或超过 X 射线图像增强器，并具有高射线照相成像性能？”为了解决这个问题，这项拨款申请提出了一项雄心勃勃、重点突出的研究计划，以定量研究两种策略：一种涉及与连续光电二极管结构耦合的像素内放大电路，用于间接检测入射辐射；另一种涉及像素内放大电路，该电路耦合到连续光电二极管结构，用于间接检测入射辐射。另一种涉及用于直接检测的高增益光电导转换器材料（碘化汞）。通过迭代开发一系列包含这些创新的小面积和大面积原型成像仪，将在相关成像条件下定量检验这些策略的有效性。这项研究的成功完成将有助于创建一种更先进的 X 射线成像技术，从而实现更高性能的 AMFPI 系统。在所有临床条件下，此类系统将提供优于现有 XRII 的空间分辨率和检测量子效率 (DQE) 性能，并且 DQE 性能优于现有胶片屏幕和计算机放射成像系统。表现出这种性能水平的技术的发展可能会对数字放射学产生深远的影响。

DESCRIPTION (provided by applicant): Active-matrix flat-panel imagers (AMFPIs) have undergone extensive research and development since their initial conception approximately 14 years ago. As a result of these efforts, this x-ray imaging technology is presently being introduced to a wide variety of clinical environments. While diagnostic AMFPIs offer definite benefits over older conventional devices, present indirect and direct AMFPI technologies suffer from inherent limitations that severely restrict their performance under the low-exposure conditions commonly encountered in fluoroscopy. Specifically, existing AMFPI devices suffer from a relatively large additive noise compared to the gain of the system. Research leading up to this proposal has specifically identified two innovative strategies that have shown particular promise for eliminating these limitations. Consequently, the question to be examined in the proposed research is: "Is it feasible, through the development and incorporation of specific fundamental innovations to imager design, to develop large area, advanced technology, fluoroscopic AMFPIs with performance levels matching or exceeding those of x-ray image intensifiers under all conditions, and capable of high radiographic imaging performance?" To address that question, this grant application proposes an ambitious, focused program of research to quantitatively investigate the two strategies: one involving in-pixel amplification circuits coupled to a continuous photodiode structure for indirect detection of the incident radiation; and the other involving a high-gain photoconductive converter material (mercuric iodide) for direct detection. Through the iterative development of a series of small and large area prototype imagers incorporating these innovations, the effectiveness of the strategies will be quantitatively examined over the relevant imaging conditions. The successful conclusion of this research will facilitate the creation of one of more highly advanced x-ray imaging technologies allowing the realization of higher performance AMFPI systems. Such systems would offer spatial resolution and detective quantum efficiency (DQE) performance superior to existing XRIIs and DQE performance superior to existing film-screen and computed radiography systems under all clinical conditions. The development of technologies exhibiting such performance levels could have a profound impact on digital radiology.