Digital x-ray imaged based on Hgl2 polycrystalline films

基于 Hgl2 多晶薄膜的数字 X 射线成像

• 批准号: 6525970
• 负责人: Jan S Iwanczyk
• 金额: $ 37.85万
• 依托单位: PHOTON IMAGING, INC.
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-01 至 2003-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6525970
• 关键词: bioimaging /biomedical imaging; biomedical equipment development; computer assisted diagnosis; digital imaging; image enhancement; image processing; iodine; mercury; molecular film; phantom model; radiation detector; radiography; technology /technique development

The goal of this proposal is to develop a new detector technology for digital x-ray imaging based on HgI2 polycrystalline films coupled to large area flat panel amorphous silicon (a-Si:H) thin-film transistor (TFT)-addressed readout arrays. This novel imaging detector when optimized will provide order of magnitude improvements in sensitivity to x-rays and superior spatial resolution compared to detectors utilizing scintillating phosphors coupled to a-Si:H readout arrays. The increased sensitivity of the detector will allow for a ten-fold reduction in radiation dose to a patient for an equivalent quality image. The enhancement of the spatial resolution will have a direct impact on the quality of the image, which has paramount importance in many medical diagnostic procedures such as mammography. In addition, digital capabilities will allow for convenient film-less image acquisition, retrieval, and storage. Digital image processing, computer-assisted diagnosis, and the ability to provide real time images have distinct advantages in many medical diagnostics. During Phase I of this proposal we developed techniques for highly controlled growth of polycrystalline HgI2 films in terms of their thickness, sizes of the polycrystalline grains, uniformity of layers and good electrical properties. In the Phase II effort we will finalize the HgI2 film development and construct x-ray imaging detectors using initially small commercial flat panel a-Si:H readouts (approximately 2"x2"). Then we will scale up the film growth equipment and construct large area (approximately 14" x 17") x-ray imaging detector. The film growth process will be optimized for low production cost. This new x- ray imager will be characterized and compared with current commercial detectors in terms of spatial resolution, gain, linearity, noise, uniformity, and detective quantum efficiency. The imaging capabilities will be tested in our laboratory and at UCLA School of Medicine with the use of slits and phantoms. PROPOSED COMMERCIAL APPLICATIONS: There is a strong interest in application of digital radiographic detectors for medical diagnostic applications, nondestructive evaluation of materials, x-ray diffraction of biological and other material samples, and astronomical observations. Conservative estimates are that in the medical area alone there are over 600 x-ray images produced per 1000 population per year. The proposed detectors will be highly attractive to this enormous commercial market segment due to the order of magnitude performance improvements that they will offer.

本提案的目标是开发一种基于HgI2多晶薄膜耦合到大面积平板非晶硅（a- si:H）薄膜晶体管（TFT）寻址读出阵列的数字x射线成像新探测器技术。与利用闪烁荧光粉耦合到a-Si:H读出阵列的探测器相比，这种新型成像探测器在优化后将提供对x射线的灵敏度和优越的空间分辨率的数量级提高。探测器灵敏度的提高将使病人的辐射剂量减少十倍，以获得同等质量的图像。空间分辨率的提高将对图像质量产生直接影响，这在许多医学诊断程序（如乳房x光检查）中具有至关重要的意义。此外，数字能力将允许方便的无胶片图像采集、检索和存储。数字图像处理、计算机辅助诊断以及提供实时图像的能力在许多医学诊断中具有明显的优势。在本提案的第一阶段，我们开发了在厚度、多晶颗粒尺寸、层均匀性和良好电性能方面高度控制多晶HgI2薄膜生长的技术。在第二阶段的工作中，我们将完成HgI2胶片的开发，并使用最初的小型商用平板a-Si:H读出器（大约2“x2”）构建x射线成像探测器。然后，我们将扩大薄膜生长设备的规模，并构建大面积（约14“x 17”）x射线成像探测器。优化薄膜生长工艺，降低生产成本。这种新型x射线成像仪将在空间分辨率、增益、线性度、噪声、均匀性和探测量子效率等方面与现有的商用探测器进行表征和比较。成像能力将在我们的实验室和加州大学洛杉矶分校医学院进行测试，使用狭缝和幻影。拟议的商业应用：在医学诊断应用、材料的无损评估、生物和其他材料样品的x射线衍射以及天文观测方面，对数字射线照相探测器的应用有着浓厚的兴趣。保守估计，仅在医疗领域，每年每1000人就有600多张x射线图像。由于它们将提供数量级的性能改进，所提出的探测器将对这个巨大的商业市场细分具有很高的吸引力。