【正文】
uperposition of multiple shifted arrays of such pinholeprisms, and show that they all contribute to the ?nal image in a /f similar way. Lippmann’s integral photography is based on this coherent action of di?erent arrays. It can be viewed as the limiting case where the plane is made pletely of 36 pinholeprisms and all the light goes through. Each microlens is formed by the corresponding prisms, as a Fresnel lens. Wideangle lens has a much larger field of view than mon cameras, and is able to capture more information from the environment. Thus, it plays an important role in kinds of applications which desire more information with fewer cameras, such as supervisory systems, visions of mobile robots, visions in manufacturing systems, etc. In our 3D welding seam extraction system, a wideangle lens is adopted to capture the welding seam information. However, the sever image distortion brought in by the wideangle lens should be tackled in order to meet the reconstruction precision as high as . The realtime ability of the welding seam system puts forward another requirement. Therefore, a simple and efficient method for calibrating camera lens distortion should be proposed. In this paper, we introduced our welding seam ext