Structured laser light is a widely used method for obtaining 3D range information in Machine Vision. However, The structured laser light method is based on assumption that the surface of objects is Lambertian. When the observed surfaces are highly specularly reflective, the laser light can be detected in various parts on the image due to a specular reflection and secondary reflections. Since these reflections cause wrong range data, the image sensor is not suitable for specular objects. To discriminate wrong range data from obtained image data, A new algorithm has been proposed by using the cross sections of image blocks. To show the performance of the proposed method, a seriese of experiments was performed on the simple geometric shaped objects. The proposed method shows a dramatic improvement of 3D range data better compared to the typical structured laser light method.
