Abstract
Our color perception is characterized by subjective influences. Color measurement enables an objective description of colors. In this process, white light is sent onto a color sample and the reflected rays are measured as a percentage compared to a white standard. The physiological standard color values are first calculated from the physical measured values by standardized conversions. From these, the L*a*b* values can be determined as they are given by the CIE (Commission Internationale de l’Éclairage). While one geometry is sufficient for color pigments to describe them, several defined geometries are required for aluminum and interference pigments. These geometries (illumination and observation angles) are specified for the different measuring instruments.