Other

Agfa Gevaert Nv

Mario Verbruggen

Serge M Tavernier

Dirk K Broddin

A method and system for reproducing an image on a carrier, the method includes: generating a conjoined first and second sub-image, each representative for a portion of the image; defining an overlap region where both sub-images give a contribution to the internal optical density of the carrier; dividing the overlap region in a partition of microdots; establishing for each sub-image a peripheral edge in the overlap region; increasing the contribution by the first sub-image from the peripheral edge of the first sub-image to the peripheral edge of the second sub-image; and assigning to at least one microdot an intermediate microscopic density different from a minimum or maximum microscopic density of microdots; wherein the contribution increases the microscopic density of the microdots by density steps smaller than half the difference between the minimum and maximum microscopic densities of the microdots.

Screening method for overlapping sub-images

For the reproduction of originals, images are generated on an image carrier, for example by printing. The imaging device that generates the image is usually not capable to cover at once the complete image area on the carrier. If the device is capable to cover the full width of the image area, the image may be generated line by line. Devices not having this capability will generate a first portion of an image line on the carrier. An adjacent second portion of the image line is then generated by another imaging device or after a period of time by the imaging device that generated the first portion. The region where the first and second portion meet on the carrier may cause visual artefacts on the final reproduction due to spatial misregistration of the adjacent line portions. This problem is solved by dividing the image in adjacent sub-images having an overlap zone on the carrier. Within this overlap zone two sub-images will be generated on top of each other for reproducing the original image in that zone, thereby reducing or avoiding the artefacts. According to one method, the resulting optical density of the first and second sub-image is reduced within the overlap zone as the outer edge of the sub-image in the overlap zone is approached. The density reduction may be achieved by reduction of the microscopic density of individual microdots or by reduction of the dot percentage or by a combination of these techniques.

Growing community of inventors

Baal, Belgium

Mario Verbruggen