3D measurement technique is the core of the 3D scanner,and grating projection technique is one of the most promising 3D measurement techniques.In this paper,a simple 3D scanning system was built up with a projector,a camera and a computer.The projector projected grating,and the camera collected the images and transferred them to the computer.After data analysis and processing,the 3D profile of the target object was finally rebuilt by means of the 3D information reconstruction algorithm we proposed.The 3D information reconstruction algorithm took advantage of structured light with Gray coding,and the work principle of the designed 3D scanning system was simple and realizable.The experimental results show that the system is able to quickly and efficiently rebuild the 3D profile of the target object,and has obvious advantages on such technical indexes as scanning speed,resolution,reconstruction speed and accuracy.It is applicable in robot vision,virtual reality and other fields.