COLOUR MEASURING METHOD AND DEVICE

摘要

The system includes a signal acquisition chain with a video camera (2), a microprocessor (3) and a cathode-ray tube display (6). The camera has three charge-coupled devices (8-10) delivering analogue red, green and blue signals for each pixel of the image of an object (O) exposed advantageously to a xenon lamp (7). The microprocessor incorporates a three-channel digitiser (6) providing 8-bit encoded signals. The transfer matrix and a correction function for nonlinearity of the chain are computed iteratively from known trichromatic components in a primary-colour reference system with at least two grey levels.