1. A wide-angle image pickup unit, comprising at least two cameras to take digital images, wherein said two cameras are arranged in such a manner that optical axes of said two cameras cross perpendicularly each other on a same plane and images of wide field angle with the crossing point as a center enable to be acquired, and wherein parts of field angles of said two cameras are superimposed on each other and an overlapping portion is formed by said two images superimposed on each other, and stereoscopic measurement can be performed based on said two images of said overlapping portion.