Hardcopy apparatus and method
AssigneeHewlett-Packard Development Company, L.P.
InventorsFerran Vilanova, Ramon Borrell
Life of this patent
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Abstract
In a method of printing with overlapping printhead dies, artifacts in the printed image caused by the printing nozzles in the overlapping region are removed, either by measuring the width of the band produced in the overlapping region and selecting an appropriate depletion or propletion printing mask for subsequent printing operations, or by printing out a test pattern in which areas corresponding to a range of depletion and propletion masks are printed out and the optimal mask is selected for subsequent printing operations. The dies overlap by only a few rows of nozzles. The method may be employed in fixed printhead apparatus (e.g. page wide arrays) or in a scanning printhead apparatus.
Claims19
A method of printing in a hardcopy apparatus in which relative movement occurs between one or more printhead dies comprising nozzles and a print medium, in which adjacent die positions relative to the medium partially overlap, wherein the nozzles of the die(s), at least in the overlapping regions, are fired to produce a test pattern on the print medium, the test pattern is examined, and the result of the examination is used to produce a printing mask for controlling the firing of the nozzles in the overlapping regions in subsequent printing operations employing the die(s), wherein the examination of the test pattern comprises measuring the width of an artifact therein caused by the overlapping region.
A method of printing in a hardcopy apparatus in which relative movement occurs between one or more printhead dies comprising nozzles and a print medium, in which adjacent die positions relative to the medium partially overlap, wherein the nozzles of the die(s), at least in the overlapping regions, are fired to produce a test pattern on the print medium, the test pattern is examined, and the result of the examination is used to produce a printing mask for controlling the firing of the nozzles in the overlapping regions in subsequent printing operations employing the die(s), wherein the overlap between adjacent die positions corresponds to up to three nozzle spacings.
A processor arranged to control printing in a hardcopy apparatus, the processor comprising means for producing relative movement between one or more printhead dies and a print medium, in which adjacent die positions relative to the medium partially overlap, means for firing the nozzles of the die(s), at least in the overlapping regions, to produce a test pattern on the print medium, means for examining the test pattern, means for using the result of the examination to produce a printing mask, and means for using the printing mask to control the firing of the nozzles in the overlapping regions in subsequent printing operations employing the die(s), wherein the examination of the test pattern comprises measuring the width of an artifact therein caused by the overlapping region.
A hardcopy apparatus comprising one or more printhead dies comprising nozzles, and means for advancing a print medium relative to said die(s), the arrangement being such that adjacent die positions relative to the medium partially overlap, means for causing the nozzles to fire to produce a test pattern on the print medium, and means for controlling the firing of the nozzles in the overlapping regions in subsequent printing operations in dependence on the result of an examination of the test pattern, wherein the examination of the test pattern comprises measuring the width of an artifact therein caused by the overlapping region.
Dependencies are inferred from the claim text.