trevista® is based on a patented "shape from shading" technology, which means that information on the three-dimensional shape of an object can be deduced from the shading of its surfaces.
A dome-shaped diffuser that is structurally illuminated by several light sources is used for the inspection – in this example a coin. Four result images are calculated from several input images. These include two slope images in the x and y direction, which are mainly used to evaluate defects with a preferential orientation.
The curvature image is orientation-independent and contains all the topographic information of the two slope images. A 3D view of the local surface can be optionally generated in just a few split seconds.
The texture image evaluates the surface reflectance so that defects such as stains and rust can be found. In the example of the coin, the differing gray values indicate differing material properties.
The combination of trevista® result images enables the reliable detection of a wide range of defects for demanding inspection tasks.
slope image in x direction
slope image in y direction