Cone-beam Ct Detection Imaging Simulation System,

CT is a high performance nondestructive testing technique,and it can reconstruct high quality image.Nowadays,a great variety of CT equipments are widely used in medicine,industry,national defence,and some other fields.However,the teaching and studying of CT is limited because of the cost of the equipments,the requirement of the operators' skills and the safety.Due to the reasons above,the simulation of CT system,which is easy to use and is appropriate to special area of application,is pressingly needed.Owing to the advantages of faster scanning speed,higher spatial resolution and better utilization of X-ray photons compared with traditional 2D CT, the cone-beam CT has a broad application perspective in practice.Therefore, simulating the cone-beam CT system is very important.In this paper,a cone-beam CT simulation system is developed for teaching and research in CT field.Distinguishing from other simulation systems,our system simulates the whole work procedure.The system is equipped with four main functions, including the simulation of the CT device control,the generation of the forward projection data,the reconstruction of the CT image,and the visualization of the measured 3-D objects.Five key modules are integrated in this system.In the device control module,the graphical models of the CT devices are built in proportion to real industry CT system, and a scene graph is employed to organize the scene conveniently.In the forward projection module,we use the programmable pipeline of Graphics Processing Unit (GPU) to make the forward projection algorithm run rapidly.In the image reconstruction module,we chose FDK as image reconstruction algorithm,and the computation process of filter and the computation process of backward projection are both accelerated by GPU.In the visualization module,the users can view the image rapidly for using the visualization algorithm based on 3D texture.In order to view the interior structure of object images,the GPU-based arbitrary clipping rendering algorithm for 3D images is used.In the interface module,a mount of public data is stored and several measures are supplied to make users and other modules of simulation system communicate effectively.The simulation system makes the most of GPU,so that the computation is accelerated obviously.Experiments show that the system runs efficiently so as to can be operated interactively by users.The design pattern of the cone-beam CT simulation system is universal,and it can be extended to design other simulation systems such as infrared ray simulation system, microwave simulation system,and ultrasonic simulation system.