Abstract: In order to achieve two inspection requirements which are high-precision inspection and the rapid inspection of internal defect of the workpiece in a process of CT inspection, a new CT detection scheme was proposed. In this scheme, an improved circular CT projection scan trajectory was combined with the incomplete projection interpolation algorithm to realize the synchronization between the projection acquisition and the real time optimal image reconstruction. In order to verify the feasibility of the technology, the corresponding fan beam CT simulation platform and test model were designed. The simulation results show that the inspection technique can detect the internal defect of the workpiece in the CT scanning process. After the scanning, the fine CT image of the workpiece can be obtained, which can effectively make the industrial CT user in a variety of detection purposes free to switch between the flexible detection needs.