| 摘要 |
Scanning device ( 1 ) for register marks ( 21, 22, 31, 32 ) printed onto a substrate ( 2 ) travelling into a polychrome printing machine. This device comprises at least one light source ( 3, 4 ) enlightening, onto the substrate ( 2 ), a lighting area ( 5 ) crossed by the register marks ( 21, 22, 31, 32 ), an optic ( 6 ) which allows obtaining onto a photosensitive element ( 7 ) the images of said register marks named as a plurality of portions ( 8 ) successively scanned with a certain scanning rate, as well as a microprocessor ( 9 ) driving the light of the light source ( 3, 4 ) and controlling electric pulses issued by pixels ( 17 ) of the photosensitive element ( 7 ). The source ( 3, 4 ) enlightens the lighting area ( 5 ) of the substrate ( 2 ) with at least one modulation of its color and/or of its intensity during the simultaneous or sequential scanning of at least two register marks. ( 21, 22, 31, 32 ).
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