Patent ID: 7465005
Filing Date: 2008-12-16
Classification: B41J,G06F,H03K,H04N,Y10S,Y10T

Abstract:
1. A printer controller for compensating for an inoperative nozzle in a printhead segmented as a bi-lithic printhead, the printhead including a plurality of nozzles associated with each pixel to be printed, the printer controller is operative to control one or more operative nozzles associated with the same pixel as the inoperative nozzle to increase the amount of printing substance expelled by the one or more operative nozzles and wherein the printer controller is further operative to: [a] form a compressed bi-level layer for a given print line intended for the bi-lithic printhead; [b] expand the compressed bi-level layer; [c] composite the bi-level layer to produce bi-level dots; [d] determine which combination of one or more available operative nozzles near the inoperative nozzle reduces perceived error in an image that the dot data forms part of, the determination being performed on the basis of a color model; [e] map the dot data intended for the inoperative nozzle to the combination of one or more operative nozzles; and, [f] pass resultant bi-level channel dot data to the bi-lithic printhead.