Surface structure reconstruction using a multispectral variable angle light source

The paper presents a method for obtaining a surface gradient using photometric stereo method. A described technique deals with the limitations of the photometric stereo method to make it more suitable for use in industrial, rather than laboratory conditions. The image is captured with a RGB camera paired with a light source which light direction and wavelength composition can be externally controlled. The information carried by three image channels is used in order to get a full resolution surface gradient. The reconstruction is then possible with a single image acquisition, which is crucial when a measured element is in motion. As an addition, the paper presents an easy and efficient method for working with non telecentric light source. The paper contains a details of computational algorithm, description of a measurement stand and an analysis of the obtained results.