Overview of the development and principle of seamless splicing technology for projection screens
With the continuous integration and development of display technology and control technology, in the field of high-end engineering, the large-screen image display formed by splicing has been widely used. The super-large picture, multi-screen display, and clear and realistic The display effect has greatly improved the work efficiency in monitoring, security, conference, simulation and other fields, and at the same time promoted the rapid progress of the technical level of these industries. Among the display and control technology based on splicing, seamless splicing technology for seamless fusion display of images is one of the important technologies. In recent years, with the development of software and hardware technology, seamless splicing technology has entered a very mature stage, and has been widely used in command and control, virtual simulation training, industrial manufacturing design, scientific research and complex decision-making processes. Applications in the fields of visual entertainment and advertising are becoming more and more common. Seamless splicing technology is a special and demanding projection display application, which can realize the fusion of multi-screen images and minimize the splicing gap to completely overlap the splicing technology. The seamless splicing technology not only requires a complete super large screen, but also has special requirements for the projection used to project a super large screen. At present, the seamless integration of ultra-large images can be achieved through high-end projectors with built-in seamless splicing technology or through external seamless splicing processors. The development of seamless splicing technology has experienced three stages of pure hardware integration technology, pure software integration technology and software and hardware integration technology. Pure hardware fusion technology is to fuse images through optical shading processing, pure software fusion technology is to complete image fusion through electronic circuit processing, software and hardware fusion technology refers to both optical shading fusion processing and electronic fusion processing. Since hardware fusion can better handle the black balance of the fused image, and software fusion can better handle the white balance of the image, the combination of the two software and hardware fusion technology can perfectly realize the true reproduction of the fused part of the color image. In terms of splicing effect, seamless splicing technology has also gone through three stages of development: hard-edged splicing, overlapping splicing and soft-edged fusion splicing. Hard-edged splicing has obvious dividing lines (ie, physical splicing), which cannot realize the integrated display of panoramic view; overlapping splicing refers to overlapping the images projected by two projectors in a superimposed manner at the splicing place, but this kind of splicing obviously exists The defects of the over-bright area due to the brightness superposition at the splicing place affects the realization of the seamless effect. Soft edge fusion splicing is processed by edge fusion technology, which not only realizes the complete fusion of the two sides, but also eliminates the over-bright area caused by overlapping splicing, and the soft edge fusion splicing can adapt to the splicing of various curved surfaces such as planes, cylinders, and spheres. , Has a wider range of applicability.