Abstract: The invention relates to a method and a measuring arrangement. The method comprises radiating optical radiation at a first moment in time to a surface area of the surface of the object from a radiation direction, the radiation being part of optical radiation comprising different intensities at different points of its intensity profile. The surface area is imaged to generate image information by performing the imaging from an imaging direction that deviates from said radiation direction by a known direction difference. Said radiation and imaging is performed at least at two other moments in time. An intensity value ratio is generated from intensity values comprised by the imaging information generated from the radiated surface area, the ratio determining the point on the intensity profile. The height of the surface area is determined for determining the shapes of the surface of the object.

Abstract: A three-dimensional inspection system and method is used to obtain information about three-dimensional articles with specular surfaces having a shape and positive or negative height by projecting a pattern of light onto the articles at an oblique angle. The system includes a patterned light projector with optical axis disposed at an oblique angle with respect to the plane of the article being inspected, an extended light source, and an image detector disposed above the article to detect the image of the pattern on the article. The light pattern includes lines with a substantially equal thickness and spacing. The spacing of the lines is greater than a spacing or pitch of the specular elements. An image processor, coupled to the image detector, receives the image, locates the lines, and measures the lateral shift of the lines. Height information is determined from the lateral shift and projection angle using triangulation.