Patent ID: 6281913
Filing Date: 2001-08-28
Classification: B41J

Abstract:
A method of operating an inkjet printhead for printing on a substrate,the printhead having an array of channels;a series of nozzles which communicate respectively with said channels for ejection of droplets therefrom;connection means for connecting the channels with a source of ink;and electrically actuable means associated with each channel and actuable a plurality of times in accordance with print tone data, thereby to eject a corresponding number of droplets to form a printed dot of appropriate tone on the substrate;the method comprising the steps ofapplying a one or a plurality of electrical signals to the electrically actuable means associated with a channel in accordance with the print tone data, each signal having a duration chosen such that the velocity of the corresponding ejected droplet is substantially independent of (a) whether or not channels in the vicinity of said selected channel are similarly actuated to effect drop ejection simultaneously with drop ejection from said selected channel, and (b) the number of droplets which are ejected in accordance with the print tone data.