A Novel Micro-Multifocus X-Ray Source Based on Electron Beam Scanning for Multi-View Stationary Micro Computed Tomography

摘要

We developed a new prototype micro-multifocus X-ray source based on electron beam scanning (MMFEBS) for multi-view stationary Micro Computed Tomography (multi-view stationary Micro-CT). This micro-multifocus X-ray source includes an electron gun, electron beam deflection coils, a dynamic condensor, a flat panel transmission target and dynamic vacuum system. The electron beam is controlled by the deflection coils and sweeps back and forth on the flat panel transmission target. It hits a series of accurately-defined positions on the target, resulting in two-dimensional X-ray multi-focus array. A dynamic condensor is utilized to overcome the electron beam defocusing caused by the deflection. It guarantees the same high spatial resolution (better than 4 mu m) at any deflection angle. The MMFEBS, together with a rotational stage and a flat panel detector, produces a multi-view stationary Micro-CT which can obtain multi-view X-ray projection data for CT images in static condition. Micron resolution CT images obtained in our experiments showed that the MMFEBS has high resolution and good repeatability.