High-Resolution X-Ray Computed Tomography Systems for Science, Medicine and Industry

X-射线计算机断层扫描(CT)以其在医学诊断中的作用而闻名，但在过去十年中，它也已成为横跨科学、医学和工业的广泛部门的一项关键技术。由于x射线能够穿透厚重的样品并提供高分辨率信息，CT的用途非常广泛。然而，对于某些具有挑战性的样品，可能很难实现良好的对比度，特别是当样品的本征X射线衰减很弱，或者当它由具有非常相似衰减的材料组成时。此外，只有通过很长的扫描时间才能实现高空间分辨率(即检测样本中的微小细节的能力)，从而限制了该方法的吞吐量。目的和目标本项目寻求开发新的层析X射线成像方法，旨在适应更广泛的样本和成像任务，从而增加该技术的应用半径，并最终产生影响。一个具体的重点将是开发创新的高分辨率方法，包括跨长度尺度，并涉及互补对比度模式(相位对比度)，众所周知，这种模式可以为衰减对比度较弱的样品提供更好的对比度。另一个关键的重点将是开发高分辨率成像的快速方法，以提高该方法的吞吐能力。这项研究将建立在伦敦大学学院医学物理和生物医学工程系高级X射线成像组开发的创新获取技术的基础上。具体地说，该项目寻求进一步开发一种摆线采样方案，通过该方案可以以连续(“飞行扫描”)的方式收集数据，并且已知能够实现比分步采集所需的扫描时间短得多的扫描时间。该项目将调查摆线原理在高分辨率(几微米)下的应用范围。研究方法的创新该项目将结合最先进的相衬成像技术和新的采集方案。图像处理方法的创新方法(高级阶段检索、迭代图像重建、基于机器学习的处理，例如去噪)将被开发和/或集成到成像流水线中，以最大化从数据中提取的信息，并为广泛的样本重建高质量的图像。与EPSRC的战略和研究领域保持一致计划的研究横跨EPSRC的主题工程、物理科学和医疗技术。CT技术在广泛的科学领域中的促进作用也意味着该项目与EPSRC使英国成为“物理和数学科学强国”的战略优先事项保持一致。任何公司或合作伙伴都参与其中，先进X射线成像集团与几个行业合作伙伴合作，包括尼康X-Tek系统公司、ISDI、Scintacor和量子探测器。其他合作伙伴包括瑞士联邦材料科学和技术实验室和三个同步加速器(钻石、Elettra和ESRF)。

Brief description of the context of the research including potential impactX-ray Computed Tomography (CT) is best known for its role in medical diagnostics, but over the last decade has also emerged as a key technology in a breadth of sectors spanning across science, medicine, and industry. CT is extremely versatile, due to the ability of x-rays to penetrate thick samples and provide high-resolution information. However, for certain "challenging" samples it can be hard to achieve a good contrast, especially when a sample features only weak intrinsic x-ray attenuation or when it is composed of materials with very similar attenuation. Furthermore, achieving a high spatial resolution (that is, the ability to detect small details in a sample) is often only possible through very long scan times, limiting the throughput of the method.Aims and ObjectivesThis project seeks to develop new approaches to tomographic x-ray imaging targeted at accommodating an wider range of samples and imaging tasks, thereby increasing the technology's application radius and, ultimately, impact. A specific focus will be the development of innovative high-resolution approaches, including across length scales, and involving complementary contrast modes (phase contrast), which are known to provide superior contrast for samples with weak attenuation contrast. Another key focus will be the development of fast approaches to high-resolution imaging to increase the throughput capabilities of the method. The research will build on innovative acquisition techniques developed by UCL's Advanced X-Ray Imaging group in UCL's Department of Medical Physics and Biomedical Engineering. Specifically, the project seeks to further develop a cycloidal sampling scheme by which data can be collected in a continuous ("fly scan") manner and which is known to enable much shorter scan times than needed for a stepped acquisition. The project will investigate to which extent the cycloidal principles apply at high resolution (a few micrometres).Novelty of Research MethodologyThe project will combine state-the-art phase contrast imaging technology with novel acquisition schemes. Innovative approaches to image processing methods (advanced phase retrieval, iterative image reconstruction, machine learning based processing, e.g., denoising) will be developed and/or integrated into the imaging pipeline alongside this to maximise the information that can be extracted from the data and reconstruct high quality images for a wide range of samples.Alignment to EPSRC's strategies and research areasThe planned research spans across the EPSRC's themes engineering, physical sciences and healthcare technologies. The enabling role of CT technology in a breadth of scientific areas also means the project aligns with of EPSRC's strategic priority of making the UK a "physical and mathematical sciences powerhouse".Any companies or collaborators involvedThe Advanced X-Ray Imaging group works with several industry partners including Nikon X-Tek Systems, ISDI, Scintacor, and Quantum Detectors. Other partners include the Swiss Federal Laboratories for Materials Science and Technology and three synchrotrons (Diamond, Elettra and the ESRF).