Color measurement by imaging spectrometry

Spectral imaging has the potential to make spatially resolved absolute colo r measurement possible for automatic visual inspection in industrial produc tion applications. In this paper, a detailed description and evaluation of the calibration of such an imaging spectrograph is given. The reproducibili ty of the reflectance factors measured by the spectrograph is determined em pirically and the measurements are compared to those of a spectrophotometer . Based on the CCD camera sensitivity, the probability that a measured colo r is within one CIE L*a*b* unit of the-actual color is predicted theoretica lly. This result is verified in practice. (C) 2000 Academic Press.