A liquid cathode for medical imaging X-ray sources

用于医学成像 X 射线源的液体阴极

• 批准号: 10371749
• 负责人: PAUL R SCHWOEBEL
• 金额: $ 23.4万
• 依托单位: SRI INTERNATIONAL
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-12-28 至 2023-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10371749
• 关键词: 3-Dimensional; Anodes; Applications Grants; California; Cathodes; Characteristics; Clinical; Data; Development; Electrons; Elements; Excision; Failure; Federal Government; Filament; Future; Health; Housing; Human; Image; Imaging technology; Industry; International; Investments; Life; Liquid substance; Measures; Mechanics; Medical; Medical Imaging; Medical center; Metals; Motion; Performance; Persons; Reproducibility; Research; Resolution; Roentgen Rays; Sampling; Site; Source; Speed; Spottings; Surface; System; Systems Development; Technology; Time; Transducers; Translations; Tungsten; Universities; Vacuum; X-Ray Medical Imaging; X-Ray Tomography; base; clinical application; cost; design; experimental study; healing; imaging detector; imaging modality; imaging system; improved; novel strategies; technology development; tomography; tomosynthesis; vibration

PROJECT SUMMARY It is generally agreed that the development of distributed X-ray sources (i.e., systems having multiple X-ray sources contained within a single vacuum envelope) could fundamentally improve tomographic medical X-ray imaging technology by removing the need for mechanical motion of the X-ray source. Removing such motion provides the potential to develop more compact, higher-speed, and lower-cost X-ray imaging systems with better image quality, new imaging modalities, and more widespread system availability. The net result would be to make imaging systems with greater capabilities more widely available to a larger number of people. A significant impediment to achieving this result has been the lack of an appropriate cathode (electron emitter) technology for the distributed X-ray source. This grant application proposes to explore a very different approach to cathodes for medical X-ray imaging sources: a liquid cathode. This unique cathode uses an electrohydrodynamic instability to form field electron emitting sites on the surface of a liquid metal with Faraday waves, induced by slight mechanical vibration of the fluid by a piezoelectric transducer. Because the cathode is a liquid, it is self-healing, which will mitigate failure mechanisms associated with field emission cathodes used to date, thereby resulting in high reliability and long life. By distributing the resulting compact electron source elements in space, the X-ray focal spot distribution can be changed, i.e., reconfigured electronically, in real time. This approach has the potential to shift the paradigm of medical X-ray imaging systems by combining a reliable, long-lived, and robust source with an electronically reconfigurable X-ray focal spot distribution. The specific aims of this proposal focus on experiments to determine whether the liquid cathode approach has the performance characteristics required for medical imaging applications. The aims are: Aim 1. Fabricate liquid cathode testbed Aim 2. Quantify electron emission characteristics of liquid cathode Aim 3. Quantify X-ray emission characteristics of liquid cathode-based source Aim 4. Develop preliminary liquid cathode-based designs for several widely used medical imaging applications

项目概要 人们普遍认为，分布式 X 射线源（即具有多个 X 射线的系统）的发展 包含在单个真空外壳内的源）可以从根本上改善断层医学 X 射线 成像技术，无需 X 射线源的机械运动。删除此类动议 提供了开发更紧凑、更高速、更低成本的 X 射线成像系统的潜力 更好的图像质量、新的成像方式以及更广泛的系统可用性。最终结果将是 使更多人能够更广泛地使用具有更强大功能的成像系统。一个 实现这一结果的重大障碍是缺乏合适的阴极（电子发射器） 分布式X射线源技术。 该拨款申请提议探索一种截然不同的医学 X 射线成像阴极方法 来源：液体阴极。这种独特的阴极利用电流体动力学不稳定性来形成场电子 液态金属表面的发射位点具有法拉第波，由金属的轻微机械振动引起 流体通过压电换能器。因为阴极是液体，所以它具有自愈能力，这将减轻故障 迄今为止使用的与场发射阴极相关的机制，从而导致高可靠性和长寿命 生活。通过将所得的紧凑电子源元件分布在空间中，X射线焦斑分布 可以实时更改，即以电子方式重新配置。这种方法有可能改变 通过将可靠、长寿命和强大的源与 电子可重构X射线焦点分布。 该提案的具体目标集中在实验上，以确定液体阴极方法是否具有 医学成像应用所需的性能特征。目标是： 目标1.制作液体阴极测试台 目标 2. 量化液体阴极的电子发射特性 目标 3. 量化液体阴极源的 X 射线发射特性 目标 4. 为几种广泛使用的医学成像应用开发基于液体阴极的初步设计