The laser projection display system is also called multi projector system, virtual 3D laser projection display an immersive virtual environment simulation system. It is used as the display carrier of the simulation application by combining the high brightness laser projector and the circular projection screen.

　　According to the size of the ring curtain radius, usually 120, 135, 180, 240, 270, and 360 degrees of arc. Because the screen showed the radius of huge, the system is usually used for some large-scale virtual simulation applications, such as: large scene simulation environment of virtual battlefield simulation, digital city planning, 3D Geographic Information System in recent years, began to develop exhibition, industrial design, education and training, conference center and other professional fields.

　　Multi channel virtual 3D projection display system is a kind of highly immersive virtual reality display system is currently very popular, the system based on multi channel visual digital image edge fusion synchronization technology, technology support, multi-channel brightness and color balance technology and multi channel visual synchronization technology, three-dimensional digital image the output of 3D graphics computer and displayed on a large circular projection curtain wall, and the stereo imaging is displayed in the viewer's eyes, so that viewers and participants get a virtual visual feel personally on the scene. It is an important part of virtual reality system (virtual reality display system).

　　Because of the multi-channel virtual 3D projection system is composed of a plurality of synchronous operation of single channel projection display screen seamless splicing, and imaging in the annular projection screen, so the single channel and usually display system compared to the multi-channel synchronous image stitching and screen display features led to the complexity of its technology. Usually, for a perfect multi-channel virtual three-dimensional projection display system, it must have the following mature core technology to support:

　　Digital image edge fusion and seamless splicing technology

　　Channel color and brightness balance

　　Digital geometric correction (nonlinear distortion correction)

　　Multi channel visual synchronization control technology

　　Only solve the above several important technical problems, in order to successfully generate real-time 3D digital graphics, 3D graphics computer real-time synchronization output and displayed in a certain radius and curvature of the giant ring projection screen, eventually forming a very high resolution, without any distortion of the three-dimensional digital image. So, in the virtual simulation of numerous multi-channel projection display system is a high technology content of virtual reality display system, the hidden risk is self-evident, this technical risks require the user to directly to the selection of suppliers more cautious.