Patent ID: 6012792
Filing Date: 2000-01-11
Classification: B41J

Abstract:
An an inkjet printer having a carriage unit with at least one print head mounted thereon for printing on a sheet of print media at least one copy of a scanned document image, the copy of the scanned document image being formed by a plurality of swaths;wherein certain individual ones of said plurality of swaths are monochromatic formed of black ink droplets only or single colorant ink droplets only distributed in various swath densities on the print media;wherein certain other individual ones of said plurality swaths are polychromatic formed of both black ink droplets and colorant ink drops or multiple colorant ink drops distributed in various swath densities on the print media said inkjet printer, comprising:velocity control means coupled to the carriage unit for causing the carriage unit to advance along a rectilinear path of travel at one of two different velocities during the formation of the individual ones of said plurality of swaths forming the copy of the scanned document image;one of said velocities being a first high speed velocity for facilitating the printing an individual one of the swaths having a black ink droplet density exceeding a given threshold level in at least one region of said individual swath and a colorant ink droplet density not exceeding said given threshold level in all the remaining regions of said individual swath;another one of said velocities being a second high speed velocity for facilitating the printing another individual one of the swaths having a colorant ink droplet density exceeding said given threshold level in at least one region of said another swath regardless of the black ink droplet density in said another swath.