REQUIREMENTS FOR OPTICAL DETERMINATION AND EVALUATION OF GRAPHIC AND/OR TEXT ON BLUE-FORM MODELS WITH A COLOUR BASIS

摘要

A colour separator (4) separates the beam of light depending on its colours into a longer wavelength transmission ray (T) and a shorter wavelength reflection ray (R). The transmission ray (T) and the reflection ray (R) are associated each to their own, appropriately positioned sensors (6, 7). A coloured filter adapted to the basic human sensitivity is arranged in the path of the reflection ray (R) between the colour separator (4) and the sensor (7).