Development of ultra-fast X-ray computed tomography scanner system

The development of an ultra-fast X-ray computed tomography (CT) scanner system has been achieved. This system can operate under the scanning time of 0.5 milliseconds/slice and give 2,000 slices/second. The original object of interest is in a transient or unsettled state of multiphase flow to measure the instantaneous phase distribution. An improvement of scanning speed was required to reduce the effects of motion artifact. The mechanical motion mechanism of a conventional CT scanner is a major obstacle to improve the scanning speed. Therefore, the concept of electrically switching the electron beam is adopted to reduce the scanning time. The present developed system has 60 stationary X-ray tubes and stationary 584 cadmium telluride (CdTe) semiconductor detectors. The excellent performance for the measurement and visualization of dynamic events of multiphase flow is confirmed by measuring moving acrylic resin phantoms and the air-water two phase flow in a tube or a 3/spl times/3 rod bundle. In addition, the system's feasibility for application to the medical field is demonstrated by trial application to the movement of a dog's heart, though the requirement remains to improve the image quality. It was confirmed by a simulation that this improvement will be achieved by increasing the number of projections.